Meeting abstracts

Abstracts of research presented at the Australian Society of Orthodontists’ 24th Congress held in Adelaide, Australia, 29 March-2 April 2014

Doctors’ Program distalisation is also needed for the correction of a Class II malocclusion resulting from bone-anchored Class New 3D imaging insights into Class II and III III orthopedics in growing children. correction Two types of biomechanics can be used: sliding of the Lucia Cevidanes teeth along a light archwire or ‘en masse’ retraction of University of Michigan, School of Dentistry, Department of Orthodontics the whole dental arch with nearly full size rectangular and Pediatric Dentistry, USA wires. Treatment efficiency will mostly depend on 3D imaging now elucidates dental compensations and control of the vertical dimension during distalisation skeletal changes in different approaches for orthopaedic of the lateral segments. Bite opening can be obtained correction of Class II and Class III malocclusions. by sequential bonding or with intrusion auxiliaries. While longitudinal data for orthopaedic correction is currently only short-term, surgical correction may 3D assessment of maxillary, mandibular and also show remarkable post-surgical adaptations and glenoid fossa changes associated with bone relapse. The envelope of changes with orthopaedic and surgical correction has now been updated with anchored midface protraction new understanding of 3D facial changes relative to the Hugo De Clerck cranial base and with bone remodelling and response Private Practice, Brussels, Belgium to growth and treatment. Maxillary hypoplasia is frequently found in patients with a Class III malocclusion. Conventional treatment involves the use of a protraction facemask to advance Arthur Thornton Taylor Lectures the maxilla. However, such appliances often have unwanted side effects including upper incisor The use of miniplates for non-extraction proclination and clockwise rotation of the mandible, treatment of Class II malocclusions resulting in an increased vertical dimension. Hugo De Clerck Miniplates can be used for intermaxillary orthopaedic Private Practice, Brussels, Belgium traction. Class III elastics can be fixed between a Bollard The main advantage of skeletal anchorage by modified anchor on the infra zygomatic crest of the maxilla and miniplates is their fixation at a distance from the dental another in the canine region of the mandible of young arch. It makes them very suitable for distal movement growing patients. A prospective study of 25 consecutive of the complete upper arch in Class II treatment cases, based on the registration on the anterior cranial without extraction of premolars. No headgear and base of a CBCT before and after orthopaedic traction, almost no Class II elastics are needed. This may be revealed a forward displacement/modelling of the maxilla and zygoma as one unit. Because of pure useful for treatment of adult Class II cases showing skeletal anchorage, no dental compensations of the relapse of orthodontic treatment where previously upper incisors were found. premolars have been removed. Furthermore, it can be a good alternative for treating nonextraction However, our studies show that mandibular shape, adult Class II subdivision 2 malocclusions instead of rather than mandibular size, was also affected by this a combined orthodontic-surgical approach. Molar bone anchored intermaxillary traction. A restriction of

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forward displacement of the chin, by a combination Dealing with difficult kids of a slight swing-back of the ramus and closure of Mark Le Messurier the gonial angle, was commonly observed. Contrary Private Practice, SA, Australia to the outcome of face mask therapy, there was no posterior rotation of the mandible. Furthermore, a Who are the ‘difficult kids’? high correlation was found between the remodelling Are they those who constantly squirm in the chair of the anterior and posterior eminence of the glenoid causing you to stop and start? Are they those who fossa and displacement of the opposed condylar refuse to open their mouth or have a hypersensitive gag surface. This resulted in a slight posterior relocation reflex? What about the kids who just won’t comply? of the articular fossa. The kids who won’t wear their appliances or rubber Treatment outcome after the completion of growth bands, or those who keep breaking their brackets off? will be needed, to assess long-term stability of bone- Luckily these are relatively few, but uncooperative kids anchored orthopaedics and to determine the percentage make bad patients and cause problematic outcomes. of these patients who will still need surgical correction. What about the group of kids who won’t clean their teeth? You know them - the ones you show their dirty Vitamin D deficiency teeth to in the mirror. Then you invite the parents to come over and look as well. To your horror, the Bronwyn Scopacasa parents look, shrug and say, ‘I nag him about cleaning Adelaide Dental Hospital, Adelaide, SA, Australia his room, doing his homework and I tell him to brush Vitamin D deficiency is common amongst Australians his teeth. He doesn’t listen to me, what can I do?’ You and is a significant public health issue. feel like saying, ‘Well, why don’t you start acting like Vitamin D plays an important role in the maintenance a proper parent. Why don’t you turn off the TV and of bone health by improving calcium absorption from take away his bloody phone until he does it!’ But, you the intestine and mineralisation of bone matrix. Very don’t. Instead, you burn with frustration inside. low levels of Vitamin D may result in bone and muscle Do you know why they’re difficult? Have you pain and poor bone mineralisation in children and considered what’s driving this tricky behaviour? What adults. Low levels will also contribute to osteopaenia can you do about it? and osteoporosis, leading to fragility fractures. Welcome to a session bursting with real understandings The main source of Vitamin D is exposure to the sun’s and practical tips for every orthodontist, nurse, ultraviolet B radiation, with only about 10% obtained hygienist and receptionist. One thing is for sure - from food such as fatty fish, eggs, UV-irradiated possessing a savvy set of tools to draw from is essential mushrooms and fortified margarine and milk. Due when confronted with a ‘difficult kid’. The bonus is to the high prevalence of skin cancers in Australia, that these very same tips may be lifesavers at home there are guidelines on the amount of sun exposure with your own children! that is considered safe. Consideration also needs to be given to latitude, season, time of day, skin colour, age, clothing, previous history of skin cancer and medical Why can’t children just grow the right conditions. number of teeth? There are certain groups within Australia, who are Martyn Cobourne at risk of developing Vitamin D deficiency and these King’s Dental Institute, Department of Orthodontics and Craniofacial groups should be identified and managed according to Development, UK the extent of the deficiency. Variation in tooth number is a common clinical Low Vitamin D has been associated with other problem frequently encountered by orthodontists. In conditions including multiple sclerosis, diabetes, recent years, significant advances have been made in colon cancer, heart disease, autoimmune diseases and our understanding of how teeth are generated during some mental health conditions; however, more long- development. The molecular interactions required term research is required to determine if there is a to create a tooth are mediated by different signalling causal relationship. Trials are currently underway. molecule families, which often act reiteratively. Whilst

100 Australian Orthodontic Journal Volume 30 No. 1 May 2014 MEETING ABSTRACTS considerable information is now available on how Learning objectives: these molecules interact to produce an individual 1. Outline the rationale and priorities for optimal tooth, much less is known about the processes that ‘patient-oriented treatment plan’. control overall tooth number within the dentition. 2. However, several developmental models are now Describe the clinical details and correct timing for starting to provide insight into the mechanisms ortho, perio and restorative procedures. that achieve this. Here, we will review the current 3. Illustrate how to combine orthodontic, periodontal evidence on how tooth number is controlled during and restorative procedures in order to manage the development, focussing on developmental models soft and hard tissues in cases of severe periodontal and discussing their relevance to variation that is seen breakdown. in the human dentition.

Next generation mini-implants for next Missing incisors: orthodontics and generation orthodontics periodontal breakdown Dieter Drescher Marco Rosa Heinrich-Heine-Universität Düsseldorf, Poliklinik für Kieferorthopädie, Insubria University, Trento, Italy Germany

Even if the introduction of implants has reduced the Mini-implants have become a common treatment popularity of orthodontic space closure, a natural modality in orthodontics due to their versatility, tooth root could still be a better alternative in the minimal invasiveness, and cost effectiveness. Still smile area. today, the alveolar process is the most preferred The lecture will show and discuss the crucial insertion site. However, due to varying bone and soft aspects of orthodontic, periodontal and restorative tissue conditions, orthodontists are still confronted interdisciplinary treatment in growing and adult with an average loss rate of 16.1% as reported in patients presenting with missing teeth in the smile area recent literature. with and without periodontal breakdown. Overall To enhance success rates, five strategies were treatment goals are ideal final restorations, function developed: (1) selection of the optimum insertion and a balanced smile, in addition to long-term site, (2) avoidance of root contact, (3) staying out of stability. The role of orthodontics will be specifically the path of tooth movement, (4) the use of tandem focused, as a fundamental part of overall treatment, implants, and (5) the use of implants with sufficient from treatment plan to the possibility of providing length and diameter. By applying these strategies, loss extra benefits: rates could be decreased to values as low as 2.4%. • Orthodontics is an excellent way to remodel and The selection of the anterior palate as a primary ‘regenerate’ new alveolar bone and soft tissue in insertion site in the upper jaw rendered the insertion cases with healthy periodontal conditions and in of mini-implants in the alveolar ridges obsolete. A new patients with extensive loss of periodontal support. generation of mini-implants, with interchangeable • Orthodontics could be an alternative (or a support) abutments, was developed that allow integration to the surgical regenerative procedures (GTR- into conventional orthodontic mechanics. Simplified insertion procedures and versatile mechanics have GBR). paved the way for routine use without the need for The main points discussed are: (1) age-oriented sophisticated laboratory procedures. diagnosis and treatment planning, (2) maxillary Based on clinical examples and scientific evaluation, missing laterals: rationale, clinical guidelines and new solutions for a variety of treatment tasks such as indications for optimal space closure (3) effective molar distalisation and mesialisation, molar intrusion interdisciplinary management of the roots with and extrusion, asymmetric space closure, midline minimal periodontal support, and (4) long-term correction, and anchorage of anterior and lateral stability. dental segments, are presented.

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The science and application of diagnostic modelling and remodelling activities depend upon imaging in orthodontics the coordinated activity of osteoblasts and osteoclasts. Osteoclastic bone resorption is the rate-limiting step Kelvin Foong National University of Singapore, Singapore in orthodontic tooth movement and relapse after movement. Therefore, biologic factors that influence ‘Mirror, mirror on the wall, who’s the fairest of them osteoclasts and osteoblasts can significantly impact all?’ is a question well known for its answer of truth. our ability to move teeth with orthodontic forces and As relevant as this truth is to the finale of the well- prevent relapse after treatment. This presentation will loved story of Snow White, the primary purpose illuminate fundamental concepts that underlie the of diagnostic imaging in orthodontics is to reflect biology by which orthodontic forces stimulate cells and reveal anatomic truth. Invariably, how humans within the PDL and alveolar bone to secrete molecular perceive this reflection and revelation is as variable as signals and mediate the recruitment of osteoblasts the faces one sees in a crowd. The fact of this variability and osteoclasts in response to compressive and tensile in human perception, when applied to diagnostic forces, respectively. Findings from recent studies will images commonly used in clinical orthodontics, be presented that demonstrate the clinical utility surfaces a few pertinent thoughts for the orthodontic of injectable biologic mediators for manipulation community to consider in its current use of diagnostic of orthodontic tooth movement, anchorage and images. To assist in this consideration, this lecture retention. Current information on the potential for aims to: bisphosphonates to influence orthodontic treatment • Explore the current understanding of the science efficiency and outcomes will also be presented. of diagnostic imaging. • Explore the ways diagnostic imaging has been applied in orthodontics. Biofilms – a new challenge for clinical orthodontics • Enumerate the future roles of diagnostic imaging in orthodontics. Yijin Ren Department of Orthodontics, University Medical Centre Groningen, University of Groningen, Postbus 300001 / BB72, The Netherlands

Biological mediators of orthodontic tooth Biofilms on orthodontic appliances may result movement: translation from the laboratory in many problems, such as white spot lesions on to the clinic enamel, infection of periodontal soft tissues or other complications, compromising dental and facial Nan Hatch aesthetics after an often lengthy and costly course University of Michigan, School of Dentistry, Department of Orthodontics and Pediatric Dentistry, Ann Arbor, USA of orthodontic treatment. Regular brushing is often insufficient to remove orthodontic biofilms from Orthodontic tooth movement requires the conversion their retention sites, such as the bracket-adhesive- of mechanical forces into biological signals by enamel junction. The great variety of orthodontic mechano-sensitive cells. Cell signalling, in turn, materials provides bacteria with numerous interaction promotes communication and leads to an alveolar mechanisms to colonise surfaces and form oral bone modelling response to orthodontic force. Upon biofilms. The objectives of this presentation are: application of an orthodontic force, osteoclasts resorb (1) to identify special features of biofilm formation alveolar bone adjacent to the pressure side of the tooth in orthodontic patients and emphasise the need for roots, allowing for tooth movement in the direction strong concerted action to prevent biofilm related of the compressive force beyond the constraints complications during orthodontic treatment, and of the original tooth socket. Simultaneously, new (2) specifically to discuss our results on in vitro and bone is deposited by osteoblasts on the opposite in vivo biofilm formation on orthodontic bonded side of the tooth roots, in the area from which the retainers and its susceptibility to oral antimicrobials. tooth has moved. Because relapse tooth movement must also involve bone resorption, orthodontic relapse is also a bone modelling process. Bone

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Steven Seward Lecture clinical complications such as white spot lesions, caries, sensitivity, pulp inflammation, and necrosis. This The future of CBCT and 3D imaging in presentation focuses on orthodontic biofilm-related orthodontics problems, which although not a life-threatening medical condition, constitute a huge problem due Lucia Cevidanes University of Michigan, School of Dentistry, Department of Orthodontics to the number of patients at risk, and young age of and Pediatric Dentistry, USA the majority of patients affected. It is necessary to stimulate affirmative action to control and decrease This lecture will cover diagnostic solutions on 3D image the size of the problem. We present here development analysis and inspire innovation as diagnostic strategies. of, in collaboration with a polymeric chemist, Our comprehensive set of image analysis solutions are microbiologist and physicist, a novel photo-curable continuing to evolve, built on open-source software, dental composite with strong antibacterial activity to providing the management of clinical needs through overcome the shortcomings of commercially available a customisable interface. CBCT diagnostic solutions adhesives lacking this property, but possessing low are designed to improve the practice of orthodontics cytotoxicity and uncompromised bonding to enamel. – optimising answers to clinical questions on tooth location, skeletal discrepancies and outcomes of treatment, bone remodelling and displacements, with Ten years of miniscrews indulgence: are they unparalleled performance. here to stay?

Om Kharbanda Stem cells: building a new tooth – do we All India Institute of Medical Sciences, New Delhi, India have the technology? In recent years, miniscrews have occupied a distinct and valuable place in the orthodontic treatment Mark Bartold Colgate Australian Clinical Dental Research Centre, Dental School, armamentarium. Since 2004 clinicians at AIIMS University of Adelaide, Adelaide, SA, Australia have treated more than 60 cases with intricate and complex malocclusions supported by miniscrews. Although stem cells have received considerable This presentation will detail the experience gained attention in recent years, clonogenic bone marrow by the use of this transient absolute anchorage stromal stem cells (also known as mesenchymal stem system, treatment outcome, and factors of implant cells) were first isolated and characterised almost 40 stability. Ongoing research on biological markers of years ago. Since then considerable effort has been inflammation in MICF has shown that the levels of made in determining the therapeutic applications of interleukin 1β rise significantly with peak levels at mesenchymal stem cells. Most of us are familiar with four hours after implant placement and 24 hrs after the concept of embryonic stem cells and their potential loading. Thereafter, levels gradually fall for 72 days use in tissue regeneration. More recently, reports but remain above base line for ten months of active have appeared regarding whole tooth reconstruction loading. The interleukin 1β levels in MICF of failed using mesenchymal stem cell technology. In this miniscrews remained constantly high. While peri- presentation the biology and potential for clinical use implant inflammation detected with interleukin β1 of stem cells for dental regeneration will be explored. levels is a significant cause of miniscrew failure, bone density does not seem to influence miniscrew stability. Novel antibacterial composites for SEM and energy-dispersive x-ray spectroscopy orthodontic fixed appliances (EDAX) analysis of retrieved miniscrews suggests that successful screws show some corrosion with Yijin Ren deposition of cerium at the head and neck while the Department of Orthodontics, University Medical Centre Groningen, body of the screws shows pitting, fretting and crevice University of Groningen, Postbus 300001 / BB72, The Netherlands corrosion in addition to the deposition of organic The presence of bacteria between teeth and matter and bone elements. The failed miniscrews orthodontic appliances or dental restorations could be show a greater amount of iron suggestive of persistent a major threat because they can cause a number of mucositis. As the miniscrew neck and gingival area

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are critical, the possibilities of creating a biological and then been assessed or subjected to orthodontic seal which simulates a natural tooth at the implant treatment, will be discussed with the aim of ginigiva interface, are being investigated. rationalising a conservative and viable biological This presentation will deduce research findings for approach to management. improved stability of miniscrews supported with a case series for the benefit of clinicians. Developing a pharmaceutical strategy for the prevention and treatment of craniosynostosis

Dental trauma management and Nan Hatch orthodontics University of Michigan, School of Dentistry, Department of Orthodontics and Pediatric Dentistry, Ann Arbor, USA Geoffrey Heithersay Discipline of Endodontology, School of Dentistry, The University of Craniosynostosis is a debilitating a paediatric Adelaide, Adelaide, SA, Australia condition in which adjacent cranial bones become Dental trauma is unfortunately relatively common prematurely fused. This fusion results in abnormal skull and facial shapes, and high intracranial pressure. in our fast moving, sports loving society and the Craniosynostosis has a relatively high incidence and implications of various injuries and their sequelae on the current treatment strategy for craniosynostosis orthodontic diagnosis and treatment are significant. involves surgical separation of fused cranial bones with Understanding the psychological impact of dental surgical remodelling of the skull and facial skeleton. injuries on the young trauma victims is of paramount Notably, even with an early and accurate diagnosis, importance in overall management, while knowledge craniosynostosis carries high morbidity. Many patients of the responses of the dental pulp, periodontal require multiple surgeries throughout their infancy ligament, periapical and periradicular tissues to and childhood to relieve high intracranial pressure, various injuries is essential for any rational endodontic treat recurring craniosynostosis, and normalise skull and orthodontic treatment. Preventive orthodontics and facial shapes. We are investigating the clinical in young susceptible patients can have positive effects progression and biologic process of craniosynostosis in reducing the incidence of anterior tooth trauma and associated craniofacial shape abnormalities, in while often simplifying definitive treatment at an order to develop non-surgical therapeutics for the appropriate age. The dental injuries of particular prevention and treatment of infants and children with concern to orthodontists are avulsions, luxations and this medically and socially challenging disorder. Our root and crown/root fractures. results indicate that enzymes important for controlling Tooth resorption control is a challenge for tissue mineralisation are central to the pathogenesis orthodontists and endodontists and the key to its of craniosynostosis. Significantly, this information management relies on the correct diagnosis of the suggests that enzyme replacement therapies currently particular presenting resorptive process. Lindskog has in use to treat mineralisation defects in patients with classified tooth resorption into three main categories: hypophosphatasia could be used to prevent and/or (1) trauma induced, (2) infection induced, and (3) treat craniosynostosis. If successful, this would provide hyperplastic invasive resorption. Of these, some are the first and only non-surgical treatment option for self-limiting as part of a healing process, some cannot craniosynostosis patients, greatly improving their be treated and others require either the elimination of quality of life. the initiating cause or the inactivation of aggressive hyperplastic resorptive tissue.

Root fractures can heal by hard tissue repair, the The prosthodontic-orthodontic interface interposition of fibrous connective tissue or the interposition of bone and a periodontal ligament Alister Dickson around both tooth segments. Fortunately, non- Private Practice, Adelaide, SA, Australia healing due to infection in the coronal segment can The relationship between prosthodontics and be effectively treated. orthodontics is an important one. Interdisciplinary The response of teeth, which have received injuries treatment involving each of these specialities is

104 Australian Orthodontic Journal Volume 30 No. 1 May 2014 MEETING ABSTRACTS becoming more relevant in modern dental practice as both in Australia and around the world. Specific cases demand for complex coordinated treatment increases. will demonstrate the principles used in identification. Patients have ever-increasing expectations of the The practice of forensic odontology is however not outcome of their treatment, which in turn drives without cost to its practitioners. We can be called away orthodontic and restorative specialists to pursue more from our practices at short notice, but the experiences ideal aesthetic and functional treatment results often can change our perspective on life itself. through interdisciplinary treatment. The scope of the prosthodontic-orthodontic interface is broad and in today’s specialist practice may include: PR Begg Lecture (1) isolated missing teeth through agenesis, impaction Impacted maxillary canines: the path to or premature tooth loss, for example, commonly agenic maxillary lateral incisors, (2) diminutive impaction and deliverance teeth, for example, ‘peg’ maxillary lateral incisors, (3) Kelvin Foong interdental spacing, (4) the worn dentition, particularly National University of Singapore, Singapore differential wear of individual arch segments, (5) large When a primary maxillary canine remains in the intra and interarch occlusal discrepencies of some mouth long after the early teenage years, one begins ‘mutilated’ dentitions which particularly may make to wonder why the permanent succedaneous canine restorative rehabilitation difficult and (6) oligodontia. is taking so long to erupt. Often, the tooth does not Coordinated treatment requires ample and precise erupt. What happened to the tooth with the longest communication between treating practitioners. root in the mouth? This lecture offers a short but Communication may be facilitated by a specialist’s revealing story of how permanent maxillary canines knowledge of their counterpart’s specialty stream, in become impacted and describes how the dentist order to enable them to envisage the final treatment can ‘find’ the ‘lost’ teeth. It will also highlight the goals and execute their phase of treatment to achieve problems impacted maxillary canines can cause to these goals. This presentation aims to provide an outline their neighbouring teeth, and what orthodontists do of treatment planning considerations for each of the when they ‘find’ an impacted maxillary canine. So, patient groups described above. These considerations stay tuned for the unfolding story. will be highlighted through a series of case examples.

The significance of tempororomandibular Forensic odontology – the Australian disorders in orthodontic management experience Tom Wilkinson Mark Leedham Specialist Prosthodontist with a practice limited to the management of Private Practice, Darwin, NT, Australia temporomandibular disorders and orofacial pain, SA, Australia

Forensic odontology in Australia has evolved Temporomandibular disorders are common within from dentists gaining experience in the field by our communities, being more frequent in females doing occasional casework on an ad hoc basis, to following puberty and reaching a maximum incidence structured university courses, and most recently during the reproductive years. These may involve specialist recognition by the Dental Board of muscular restriction and pain on function, repetitive Australia. Forensic odontologists in Australia now habits affecting movement, internal derangement and have significant experience and training, not only degenerative joint disease. in routine identification work, but also in Disaster Occlusal variations from ideal are not considered to Victim Identification. Disasters such as the Bali be significant in the initiation of temporomandibular Bombing and the Asian Tsunami, and at home, the disorders. These disorders are rarely improved or Victorian Bushfires in 2009, relied heavily on the prevented by orthodontic treatment. However, expertise of forensic odontologists for rapid and they may lead to difficulties during treatment and precise identification of victims. This work relied on may prevent the orthodontist from achieving their accurate ante-mortem records from dental practices treatment goals. These disorders should be fully

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assessed before treatment planning. Management of current orthodontics. With the introduction of mini- these disorders may be needed before orthodontic plates and mini-implants new options, especially in treatment commences. early treatment, have become available. It is rare that orthodontic treatment initiates or The Hybrid-Hyrax appliance is a rapid maxillary exacerbates temporomandibular disorders. Internal expander that is bone as well as tooth borne. derangements with disc displacement can be affected Employing mini-implants placed in the anterior by orthodontic treatment and progressive degenerative palate, orthopaedic forces can be applied to the skeletal changes may continue during and after orthodontic structures of the mid-face. It was demonstrated that treatment, leading to an unstable result. the force vector lies more cranially and thus provides This presentation will review the current literature more sutural opening compared with conventional in relation to orthodontics and temporomandibular tooth-borne expanders. disorders. Combining the Hybrid-Hyrax with a face mask not only prevents unwanted side effects, such as mesial movement of the molars, but also allows maxillary Passive self-ligation with the Damon protraction with application of the force vector to the appliance: where is the evidence? skeletal structures of the mid-face.

Martyn Cobourne Simultaneous rapid maxillary expansion and King’s Dental Institute, Department of Orthodontics and Craniofacial protraction can also be accomplished employing the Development, UK so-called Mentoplate. This mini-plate is inserted Self-ligating bracket systems are now a viable subapically above the chin prominence. This region treatment option for orthodontists and have proved to be a safe place for skeletal anchorage with increased in popularity over the last few years. This plenty of bone of best quality in young children. In reflects improvements in their engineering, reliability addition, aesthetic impairment by extra-oral devices and relative ease of use. However, it might also be can be eliminated in this way. related to claims of superior function made by the A clinical study is presented, which demonstrates manufacturers of these appliances. In particular, the the skeletal effects that can be expected from these Damon appliance system claims to offer significant approaches. The concept is further illustrated by advantages to both orthodontist and patient over clinical case documentation. conventional ligation and other forms of self-ligated appliances. These claims have led to a number of clinical studies Missing maxillary lateral incisors: new investigating the clinical effectiveness of the Damon procedures and indications for optimal space system in comparison with conventional ligation, closure including a randomised controlled trial conducted in our own unit. Here, we will discuss some of the Marco Rosa Insubria University, Trento, Italy findings, including pain experience for the patient, tooth alignment rates, archform changes and treatment Even if the advent of osseo-integrated implants has outcome. Are the claims relating to improved reduced the popularity of a space-closure alternative, clinical performance of the Damon appliance system it could still be the best solution in young patients substantiated by the evidence? and in the vast majority of adult patients, having as an overall goal, not only a predictable good function and a well-balanced smile, but also the long-term stability. Skeletal anchorage in orthopaedic therapy The lecture will provide the rationale, priorities in Dieter Drescher treatment planning, new crucial details regarding space Heinrich-Heine-Universität Düsseldorf, Poliklinik für Kieferorthopädie, closure biomechanics and orthodontic finishing, as Germany well as related periodontal and restorative procedures. Application of orthopaedic forces to the skeletal The inherent difficulty of treatment and the most structures of the face still presents a challenge for frequent side effects will also be highlighted.

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Finally, new indications for a space closure alternative Auxiliary program abstracts will be suggested. Incorporating Invisalign into your orthodontic Learning objectives: practice • Focusing on the crucial aspects of diagnosis and treatment planning. Igor Lavrin • Planning and managing difficult and controversial University of Melbourne, Victoria, Australia cases. The orthodontic community worldwide now accepts • Preventing ‘overtreatment’ and side effects of the use of Invisalign as a predictable treatment treatment, however complex. modality. This lecture will provide information for practices starting to use Invisalign as well as for those practices using the product routinely. Clinical tips and tricks, administrative procedures as well as patient education, both in the new patient process and clinically, will all be reviewed.

TADs explained for orthodontic assistants

Dee Macpherson Dentaurum Australasia, Concord, NSW, Australia

Sir Isaac Newton’s third law of physics has great importance in orthodontics and is at the root of many problems encountered with traditional braces. It states that: for every action there is an equal and opposite reaction. This presentation explains how TADs work by achieving anchorage without the unwanted reactions commonly experienced with other forms of anchorage. TAD treatment is simple, non-invasive and comfortable for patients. I will show examples and situations where TADs can deliver predictable results, reduce treatment time, avoid headgear wear, avoid removal of teeth and/or avoid surgery. I will also explain the risks and side effects of TAD treatment for patients.

Medically compromised patients

Sharon Liberali Director and Consultant, Special Needs Unit, Adelaide Dental Hospital, SA Dental Service, Adelaide, SA, Australia

Dental graduates, in the course of their practising lives, are increasingly likely to see medically-compromised patients with oral healthcare needs, and orthodontists are no exception. The confidence and willingness to provide treatment for this diverse group of patients is closely correlated to the quality and content of

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the dentist’s knowledge on medically-compromised patient remains anti-treatment they’ll be a headache patients. from start to finish. This lecture will discuss many of the more common medical conditions, their medical and pharmacological Business from the heart: Part 1 treatments and how these may impact on oral health with particular focus on orthodontic treatment. Andrew Hoggard Henry Schein Halas, NSW, Australia

Education on its own does not change behaviour. Motivating children For any real change to take place we need to have an inner revelation in the unseen world of the heart. Mark Le Messurier Private Practice, SA, Australia Once this takes place then we can ignite our heads for real change. This two-part seminar will take you In a perfect world, every child or teen that came on a journey of self discovery by looking first at you, your way would do what you wanted in the spirit thinking differently about business and sharing five you desired. They’d appreciate your skill and things for your heart that if put into practice may genial character. They’d be grateful for having such just change your life. Walking away you will also have specialised treatment paid for by a parent. You would some practical takeaways that will benefit you not be held in such revere that patients would gladly wear only at work, but also at home and with your friends. a twin block appliance as a fashion statement simply This seminar promises to be non-clinical, non-dental because you said so. and plenty of fun. In a less perfect world, just a few years ago, an orthodontist could have demanded compliance from a young patient with a few well-chosen tell-offs, and Links between oral and general health got it! And, if compliance wasn’t fast and forthcoming Sharon Liberali they’d ask a parent to deliver the extra measures to Director and Consultant, Special Needs Unit, Adelaide Dental Hospital, achieve it. What used to work to gain a young patient’s SA Dental Service, Adelaide, SA, Australia cooperation and respect doesn’t work nearly as well The relationship between oral health and general today. Oh yes, the world has changed! health has been increasingly discussed in the dental The truth is that the world and your patients are literature over more than a decade. There is a growing not perfect. Most need a little external motivation evidence base for ‘associations’ between chronic disease to help them along the way. Others need bucket and oral health, in particular periodontal disease, loads of encouragement and cajoling to follow your with cardiovascular disease, diabetes, osteoporosis, treatment plan because they can’t yet delay their desire premature birth and low birth weight, obesity and for instant gratification. Quite a few need convincing malnutrition, and respiratory disease (aspiration that the treatment really is in their best interest, even pneumonia). though you feel pressured by a small window of time Data from the 2004-05 National Health Survey to complete treatment. Some of your patients are identified that just over 7 million people in Australia locked into emotional and oppositional battles with have at least one chronic condition and that the parents, and unless you spot this deadlock early and proportion of people having a chronic disease increases have a plan, you will fast become a casualty. with age.1 Results from the 2007-08 National Health This session will raise a series of useful, everyday Survey show increasing prevalence of cancer (2%); strategies couched in a positive psychology approach diabetes (4%); arthritis (15%) and conditions of the - sound ideas to help kids find appealing short-term circulatory system (16%) in the Australian population 2 methods to invest in their own treatment. Kids are compared with 2001 data. far more likely to get on board when they realise they Many chronic medical conditions and/or their can make choices that advantage them. What’s the treatments have the potential to be compromised by alternative? You know the answer - most of you have poor oral health and/or may compromise oral health. discovered from bitter experience that when a young With increasing numbers of middle-aged adults

108 Australian Orthodontic Journal Volume 30 No. 1 May 2014 MEETING ABSTRACTS undertaking orthodontic treatment, understanding the requirements of defined criteria or standards. the impact that chronic disease and its treatments Accreditation is an internationally recognised can have on oral health is becoming increasingly evaluation process used to assess the quality of care important. and services provided in a range of areas including health care. References: The Australian Commission on Safety and Quality 1. www.aihw.gov.au/chronic-diseases. Accessed 4.11.2013 in Health Care drives accreditation. The commission 2. www.health.gov.au/internet/main/publishing.nsf/content/chronic is to lead and coordinate improvements in safety Accessed 4.11.2013 and quality in health care across Australia. As part of this role, the commission has developed and will maintain the National Safety and Quality Health What you need to know about functional Service standards and six of these ten standards apply appliances to dentistry.

Colin Twelftree The accreditation process has been designed to give Private Practice, SA, Australia participating practices the opportunity to establish or review policies that already exist in accordance with Removable functional appliances are an important statutory requirements. part of modern orthodontic practice. However, their successful use is thought to be largely dependent upon Participating in an accreditation process for the the cooperation of the patient. Auxiliaries within first time may seem daunting. However the ADA, an orthodontic practice can play a critical part in in collaboration with an independent accreditation ensuring excellent patient cooperation and this lecture agency Quality in Practice (QIP), has developed will show how this can be achieved. In addition, the a process, template materials and supporting mode of action of all functional appliances and the documentation to assist practices through the process. particular advantages of the Clark Twin Block will be If all practice staff are engaged in the accreditation explained. A technique to ensure absolutely perfect process it can be a very positive experience and can cooperation will be described and the use of this enhance practice efficiency, reduce risk and enhance technique will make the auxiliary an indispensable quality. member of the team. Accredited practices demonstrate that they have To reduce the time and travel considerations of the committed to an internationally recognised system patient, and to further improve practice efficiency, the of benchmarking safety and quality and they should use of the World Wide Web, utilising Facebook and significantly benefit from the process. Skype, will be explained. The incorporation of these adjuncts into the practice will not only consolidate the efficiencies of functional appliances, but also have From my side of the chair: sterilisation in the potential to enhance delivery of other orthodontic today’s orthodontic practice. For the clinical services, while making a strong contribution to the team levels of oral hygiene in the practice. Andrea Cook The use of these techniques will make you a more Orthodontic Clinical Consultant, USA valuable member of your team and improve the Today’s orthodontic teams are challenged with having orthodontic results obtained for your patients. the time, knowledge and equipment to process instruments and achieve compliance with the ADA guidelines and sterilisation protocols. We will review Practice accreditation the current guidelines and discuss tips and tricks to Mark Hutton help make instrument reprocessing safe, fun, and Private Practice, Mount Gambier, SA, Australia effective for the orthodontic team! Accreditation is independent recognition that an organisation, programme or activity meets

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Learning objectives: toxic reaction after a single use. • Understand the current ADA guidelines. Both methamphetamine and cocaine belong to • How your team can comply with the guidelines. the class of drugs known as Central Nervous System Stimulants. There are four different forms • Most common cross contamination areas and how of methamphetamines marketed in Australia with to reduce them. ICE (crystal meth) being the most potent and producing the most severe effects. These stimulant drugs cause the release of neurotransmitters within The biofilm battle – what to include in your the brain, producing an intense surge of pleasure. armamentarium However, with chronic high dose use this will alter the neurotransmitter system of the brain, leading to Susan Cartwright Scientific Affairs Manager, Colgate Oral Care, NSW, Australia degeneration and toxicity. CNS stimulant drugs have an impact on oral health Biofilm control for those wearing orthodontic by causing xerostomia and triggering bruxism and appliances is particularly important to avoid unsightly clenching which may cause tooth wear and fractures. and damaging oral disease. Where do we find biofilms Poor oral hygiene often results from extended periods and what are their properties? Why is biofilm control of drug use and there is often a high consumption of so difficult? These questions will be considered in light carbonated soft drinks. These factors, together with of the oral environment. How can effective biofilm drug induced vomiting, results in rapid breakdown of control be promoted in individuals? Evidence will be the dentition. Snorters of cocaine may suffer repeated presented to demonstrate some potential solutions to nosebleeds and occasionally develop necrosis of the this complex problem. nasal bones. When rubbed on gingival tissue cocaine This presentation will contribute towards your goal of may produce severe gingival ulceration. creating beautiful healthy smiles. There are certain warning signs that indicate drug use such as a very high caries rate in a teenager or young adult, a distinctive pattern of decay, excessive tooth ‘I heard you work at the orthodontist! Can wear, malnourished appearance, poor compliance you have a quick look at little Emma’s teeth?’ with treatment and mental health issues. Orthodontic problems in the young child – FAQs and interceptive treatment Problems with 6s Tissa Jayasekera Private Practice, Bendigo, Victoria, Australia Michael Malandris Paediatric Dentist, Plympton, SA, Australia The lecture will discuss a variety of common concerns that parents and dentists express regarding tooth The first permanent molar (FPM) is a critically alignment and development of the bite in the mixed important tooth in a developing child’s dentition. It dentition. Presentation of the various conditions and may come as a surprise that there are many children management options will be discussed. who present with FPMs that can be significantly compromised, even when these teeth first emerge. This presentation aims to highlight the more common Coke and ice problems that are encountered with FPMs by clinicians, the challenges faced and new technologies that can Bronwyn Scopacoasa aid in providing accurate diagnosis, the development South Australian Dental Service, Adelaide, SA, Australia of a diagnostic checklist prior to embarking on any Widespread drug use has a major impact on health treatment that relies on the presence of sound FPMs, care, including dentistry, and has significant social effective treatment options to restore compromised and psychological consequences. As the components FPMs and considerations that need to be made in of illicit drugs are variable and unknown, their effects deciding when a FPM with poor medium- to long- are unpredictable and it is possible to have an acute term prognosis should be extracted.

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Instrument set up and organisation Poster abstracts

Andrea Cook Orthodontic Clinical Consultant, USA A proteomic search for biomarkers of orthodontic root loss using a physiological Although organisation is not a natural strength root loss model for everyone, this management skill is critical in an orthodontic practice. Outside influences such Edwin Tan, Mike Hubbard, Paul Schneider, David Manton as regulatory compliance, environmental issues, and Jon Mangum economic factors, and incorporation of new Department of Orthodontics, The University of Melbourne, Melbourne, technology all provide good reason for orthodontic Victoria, Australia practices to commit to clinical organisation. Long- Introduction: One of the adverse effects of orthodontic term benefits include increased efficiency, effectiveness, treatment is shortening of the roots of teeth as they are and productivity. From the front office to the clinical moved through alveolar bone. In most patients this areas, the entire orthodontic team – along with the is very minimal but in some patients, more than one patients – benefit when the practice runs smoothly. third of the root may be lost, which can be detrimental to the long-term survival of the tooth. Currently, the only means to detect orthodontic root loss (ORL) Business from the heart: Part 2 are retrospective such as radiographic or volumetric Andrew Hoggard techniques that carry the biologic burden of radiation Henry Schein Halas, NSW, Australia exposure or extraction of the tooth for investigation. Education on its own does not change behaviour. Given these limitations, there is a need for more For any real change to take place we need to have sensitive and less invasive methods for detecting an inner revelation in the unseen world of the heart. ORL. It is thus proposed to identify biomarkers of Once this takes place, we can ignite our heads for ORL, which are hypothesised to be excreted in urine real change. This two-part seminar will take you on during this phenomenon. This will pave the way for a journey of self discovery by looking first at you, the development of a urinary bio-monitoring test for thinking differently about business and sharing five the detection of ORL in real-time. things for your heart that if you put into practice may Aims: This project seeks to discover biomarkers just change your life. Walking away you will also have from tooth roots that can be detected in body some practical takeaways that will benefit you, not fluids, specifically urine. This will provide a simpler only at work, but also at home and with your friends. and earlier detection method of ORL than current This seminar promises to be non clinical, non dental practice, which relies on taking serial radiographs. and plenty of fun. Materials and method: Several dentine specific proteins have been proposed as biomarkers of ORL such as dentine phosphoprotein (DPP) and its breakdown products. The aim is to discover and quantify the levels of these biomarkers in urine samples of patients undergoing physiological root loss (PRL) i.e. shortening of the roots of primary teeth prior to exfoliation during normal dental development. The PRL model has been chosen because it is hypothesised that during PRL, significant amounts of these biomarkers may be released into the bloodstream and excreted in urine. This is an ideal model to use because at this age group, it is known that root resorption is rapidly occurring and likely to provide a high yield of biomarkers. Our approach is to collect urine samples from patients aged 6 to 12 (test group; N = 20) with a control group that have lost all their

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deciduous teeth (N = 20). Samples will be analysed by technique was based predominantly upon efficiency proteomic techniques such as gel electrophoresis and of adhesive removal, damage to enamel and patient mass spectrometry. If successful, the tests may then comfort. be translated to an orthodontic population who has Conclusion: The removal of bonding material using radiographic evidence of root resorption. SSTC was the preferred technique employed by Conclusion: The potential importance of this research orthodontists in Australia for both metal and ceramic is the possibility of allowing the orthodontist to be brackets. This technique has been shown in the aware of when root resorption is occurring. This literature to be the least damaging to the enamel would allow the orthodontist to alter their treatment surface so it was encouraging to see its widespread use. mechanics in an attempt to reduce ORL. However, not all clinicians were using this technique, with approximately one quarter of orthodontists still using HSTC. Further research is needed to study the Clinician preference for various orthodontic exact techniques being used. Strategies to increase the use of the safest techniques should be considered, bonding material removal techniques such as teaching in tertiary institutions or continuing Jeffrey Tho, Josh Ch’ng, Sophie Ho, Megan Lee, Alvin Ng, professional development courses. This will help to Salim Yaptono, Paul Schneider and Nathan Cochrane ensure that clinicians are providing evidence-based Melbourne Dental School, The University of Melbourne, Melbourne, treatment for their patients. Victoria, Australia

Background: Orthodontic bracket debonding and bonding material removal is a common procedure Predictability of increasing tooth velocity in all orthodontic practices. The aim of this study using Invisalign aligners in a group of was to survey Australian practitioners’ preference teenage subjects of bonding material removal techniques following bracket debonding and the reasons which underlie the Margaret Wang, Vicki Vlaskalic, Paul Schneider and David Manton selection of their preferred technique. The University of Melbourne, Victoria, Australia Method: An online questionnaire was distributed This project will investigate the clinical accuracy of to a total of 503 orthodontists who were members ™ of the Australian Society of Orthodontists. The the Invisalign orthodontic aligner system (Align questionnaire comprised approximately 30 questions Technology, CA, USA) by comparing computer- enquiring about techniques employed: before proposed tooth movements with actual clinical tooth movement, following an increase in the rate of tooth and during bracket bonding, during orthodontic movement per set of aligners from the default 0.25 treatment and at bracket debonding and bonding mm per fortnight to 0.33 mm per fortnight. material removal. It also asked clinicians to comment on the observed frequency of enamel damage after By customising the rate of tooth movement with the bracket and bonding material removal, and to rank aligners, the goal is to achieve clinical results equivalent what they believe to be the least to most damaging to current standard treatment protocols, but with a techinques. The data obtained were assessed using decrease in the treatment time and the number of SPSS statistical software. aligners the patient needs to wear. This study aims to highlight the accuracy and predictability of Invisalign Results: 224 of the 503 (44.5% response rate) prescribed dental movements. orthodontists responded to the questionnaire. The majority of metal and ceramic brackets were bonded using resin composite 98.2% and 97.5% respectively. The preferred bonding material removal technique amongst those surveyed was a slow-speed tungsten carbide bur (SSTC), regardless of bracket type. The use of a high-speed tungsten carbide bur (HSTC) was the next most popular, followed by multi-stepped approaches. The choice of bonding material removal

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Dental and cervical vertebrae maturation A comparative histomorphological and of isolated unilateral cleft lip and palate in micro CT study into the healing and Australian children: a longitudinal study osseointegration of the Sydney Mini Screw and 6 mm orthodontic anchorage miniscrew Sarah R Ting,1 Wendy Nicholls,2 John C Winters2 and WK in the tibia and femur of New Zealand Seow1 rabbits 1School of Dentistry, University of Queensland, Brisbane, Queensland, Anastacia Bacopulos Marangu,1 Ali Fathi,2 Oyku Dalci1 Australia and M Ali Darendeliler1 2Dental Department, Princess Margaret Hospital for Children, Perth, WA, 1Discipline of Orthodontics, Faculty of Dentistry, University of Sydney, Australia NSW, Australia Aim: To investigate the dental and skeletal 2School of Chemical and Biomolecular Engineering, University of development of isolated unilateral cleft lip and palate Sydney, NSW, Australia (UCLP) children of an Australian population. Introduction: Anchorage is crucial in controlling tooth Method: This was a retrospective longitudinal cohort movement when applying orthodontic mechanics. study of 86 UCLP children who were seen and treated Recently, miniscrews have been introduced for this at the Cleft and Craniofacial Department of Princess purpose, however issues exist with primary stability. Margaret Hospital for Children, Western Australia. Immediate and delayed failure rates are reported to Orthopanthogram (OPG) and lateral cephalogram be 7% to 50% from which 15-23% is multifactorial as well as related to the specific study parameters (LC) radiographs were exposed at three-year intervals evaluated. New ways to reduce failure must be between the ages of 6 to 15 years. Children with considered. significant medical history and diagnosed syndromes were excluded. The non-cleft control samples Aim: The aim of this study on an animal model was consisted of 306 age- and gender-matched healthy to describe the dispersion of injectable bone graft children from the University of Queensland School substitutes through the cortical and trabecular bone of Dentistry and four private orthodontic practices surrounding the Sydney (SMS) over time. This is part in Brisbane. The dental age was determined from the of a larger study looking at the histological integration OPG using the method of Demirjian et al (1973). of the SMS aiming to improve the success rates and primary stability of the orthodontic miniscrew, via the Skeletal maturity was assessed from the morphology use of injectable bone graft substitutes (IBGS). of the cervical vertebrae seen on the LC as described by Baccetti et al (2005). Differences between UCLP Method: Twenty-four miniscrews were surgically placed and control children were tested using paired t-test in each proximal tibia and femur of six New Zealand and Chi square test with a significance level ofp < rabbits. Rabbits were randomly divided equally into 0.05. two groups according to the time period and surgery site. The Acute Group (AG-week 0) was sacrificed Results: Both the study and control groups were the same day of surgery, while the Chronic Group dentally advanced. There was no significant difference (CG-week 8) was sacrificed after eight weeks. Three in skeletal and dental maturity between UCLP and different site preparations were randomly assigned control girls. UCLP boys had significant dental delay involving 4 SMS with IBGS (SMS-BGS), 4 SMS at 9 years of age with a mean delay of 0.5 ± 1.2 years without IBGS (SMS), and 4 Aarhus miniscrews (AC). (p < 0.05) and a delay of skeletal growth at 12 years of Aarhus implants were inserted to serve as controls. All age (p < 0.05) in comparison with controls. However, bone sections were prepared for MicroCT. by the age of 15 years, this difference between UCLP Results: Bone sections are currently being scanned boys and controls ceased to be significant. with MicroCT, once completed, the samples will be Conclusion: UCLP boys show significant dental and prepared for histology analysis. skeletal delay at 9 years but catch up with their non- Discussion and conclusion: Despite having preliminary cleft counterparts by 15 years. micro-CT images, results cannot be definitively made until they can be compared with histological slices. A better idea of density will be available when the histological evaluation is completed.

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Prediction of the efficacy of a mandibular shape of the airway as seen during the nasendoscopy advancement splint in the treatment of examination. The area of collapse will be compared obstructive sleep apnoea using various with the smallest cross-sectional area on the CBCT to determine if there is a correlation between the two diagnostic methods anatomical positions. Volumetric measurements of Anél Blignaut,1 M Ali Darendeliler,1 Oyku Dalci,1 the airway will be analysed in relation to BMI, neck 1 2 Vasantha K Srinivasan, Peter Cistulli and Kate circumference and sub-mental vertex measurements. Sutherland2 Quantitative analyses will be used to assess differences 1Orthodontics Department, Sydney Dental Hospital, Faculty of Dentistry, University of Sydney, NSW, Australia in the results of each assessment technique between 2Woolcock Institute of Medical Research & Royal North Shore Hospital, MAS treatment response groups and non-responders. NSW, Australia

Background: A Mandibular Advancement Splint (MAS) for the treatment of Obstructive Sleep Apnoea Cytokines in gingival crevicular fluid and root (OSA) is often used as an alternative for patients who resorption in orthodontics: a pilot study

refuse or are unable to tolerate continuous positive Jenkin Chiu,1 Rajiv Ahuja,1 Alamgir Khan,2 Edmond airway pressure (CPAP) therapy. Unfortunately MAS Breen,2 Dr Oyku Dalci1 and Professor M Ali Darendeliler1 treatment is not successful on all patients and 35% 1Department of Orthodontics, Sydney Dental Hospital, Faculty of of patients have less than 50% reduction in their Dentistry, University of Sydney, NSW, Australia Apnoea-Hypopnea-Index (AHI) with their AHI 2Australian Proteome Analysis Facility, Macquarie University, NSW, remaining above five episodes per hour. Australia Aim: This study will aim to identify reliable, clinically Introduction: Orthodontically-induced inflammatory applicable predictors that will allow the clinician to root resorption (OIIRR) is an adverse and unavoidable identify those patients who will respond favourably side effect of orthodontic treatment. The aetiology to MAS treatment in order to save time and cost and of OIIRR is poorly understood, but is a complex thereby increase patient satisfaction. interaction between patient- and treatment-related risk factors. A speculated systemic immunologic Materials and methods: Fifty-one patients were recruited, all of which had newly diagnosed OSA mechanism to root resorption may explain why select (AHI > 10/hr) as demonstrated by a recent diagnostic patients experience more OIIRR than others. nocturnal polysomnograph (PSG). Demographic Aim: The aim of this pilot study is to investigate the information, medical history, anthropometric data and process of OIIRR by analysing a selection of pro- clinical dentofacial records were obtained including a inflammatory and anti-inflammatory cytokines in CBCT image of the head and upper airway in a supine gingival crevicular fluid (GCF) and correlating it to position. Prior to the commencement of the MAS root resorption craters that are identified by micro- wear, the Velopharyngeal patency was assessed by computed tomography. means of nasendoscopy with mandible advancement, Subjects and methods: Seventeen patients (10 male during tidal breathing and Müller manoeuvre. After and 7 female, Mean age 15 years 4 months ± 1 year successful acclimatisation and titration of the MAS, 9 months) with clear medical histories and upper first patients underwent a repeat sleep study to determine premolars that had complete apexification and required treatment outcome and to group them as responders, extraction for orthodontic treatment, were enrolled indicating > 50% reduction in AHI and non- into the study. A split-mouth design was used, in which responders, as < 50% reduction in AHI. the experimental tooth was subjected to 25 g of buccal Results: Results are currently pending statistical tipping force (light force group, N = 9) or 225 g of analysis. The focus will be on finding correlations buccal tipping force (heavy force group, N = 8), and between the airway shape as well as the dimensions contralateral first premolars served as controls. GCF of the smallest cross-sectional area as seen on was collected from the buccal gingival sulcus of test and reconstructed 3D images of the CBCT volumetric control premolars at six time points (0, 3, and 24 hours, datasets using version 11.0 of Dolphin 3D Imaging. 3, 7 and 28 days) using Periopaper. GCF was analysed These findings will then be compared to the anatomical for IL -1b, -2, -4, -5, -6, -7, -8, -10, -12p, and -13,

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IFN-γ, GM-CSF and TNF-α using a multiplex bead but were significantly different at T2 p( = 0.012). immunoassay technique. Control and experimental CA had the lowest mean (0.048, SD = 0.021) while teeth were extracted on day 28 and imaged with a SMS (Mean = 0.106, SD = 0.044) and SMSC (Mean computer microtomograph. Resorption craters were = 0.103, SD = 0.033) had similar means. Although identified on reconstructed images and their volumes the means for T1 were lower than T2, only SMS (p were quantified. = 0.006) showed a statistically significant difference Results pending: It is the authors’ intention to correlate between T1 and T2. The different surgical locations the volume of resorption craters in the light and heavy at T2 did not statistically differ from each other either force groups to the quantities of cytokines found (p = 0.948). the GCF over the 28-day experimental period. Data Discussion: There was a trend towards SMSC having collection and interpretation are being finalised, final more primary stability compared to SMS and CA at results and their discussion will be available in a few T1 but this was not statistically significant. It was weeks. interesting to find that the SMS group was comparable Limitations: The small sample size and the to SMSC at T2 and even having a significant difference confounding factors affecting the cytokine quantities in T1 versus T2 groups. This is probably due to the found in GCF are the most significant drawbacks of design of the SMS being retentive in nature with this study design. threads in the cortical bone as well as possible bony infiltration into the internal of the screw via the lateral exit holes after eight weeks of healing. A comparative study of the retentive Conclusion: It appears the Sydney Miniscrew, with and capability of the Sydney Miniscrew with without cement, did show a trend towards increased primary and secondary stability with only SMS 6 mm orthodontic anchorage miniscrews in showing a significant difference in secondary stability New Zealand rabbits by pull out test when compared to a normal control miniscrew. More PD Hoang,1 A Bacopulos Marangu,1 A Bilgin,2 O Dalci1 research is required with increased sample size. and M Ali Darendeliler1 1Department of Orthodontics, School of Dentistry, University of Sydney, NSW, Australia Orthodontic root resorption following heavy 2Department of Statistics, Faculty of Science, Macquarie University, NSW, Australia transverse and vertical jiggling forces Aims: To investigate the retentive capability of the Carolyn Ng Department of Orthodontics, The University of Sydney, Sydney, NSW, newly designed Sydney Miniscrew with injectable Australia bone cement in an animal model by removal torque. Material and methods: Sixteen New Zealand White Introduction: It has been suggested that jiggling tooth rabbits were divided evenly into two groups, T1, 0 movements may be responsible for root resorption in week to assess primary stability and T2, 8 weeks to the absence of overt root displacement. test secondary stability. Three groups of miniscrews, Aims: The present study aims to quantify and Sydney Miniscrew with cement (SMSC) (N = 12), compare the effects of controlled heavy transverse Sydney Miniscrew without cement (SMS) (N = 10) buccal and palatal, and vertical extrusive and intrusive and a control Aarhus (CA) 6 mm screw (N = 10) were jiggling forces applied over a 12-week period on root placed randomly and evenly between the right and left resorption, and to localise the sites of prevalence in tibial and femoral sites. The SMSC and SMS required human premolars. predrilling a 2.5 mm by 6.5 mm space and the SMSC Materials and methods: Ten patients who required had injectable bone cement PRODENSE. Removal bilateral maxillary first premolar extractions as part of torque was measured using a Motive Digital Torque their orthodontic treatment participated and provided Meter in Ncms. Friedman’s Test was use for statistical a total sample of 20 premolars. Heavy (225 g) forces analysis. were applied to the right or left first premolar with Results: Removal torque values at T1 for CA, SMS the direction of force alternating along either the and SMSC were not significantly different p( = 0.072) transverse or vertical plane every 4 weeks over a 12-

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week period. After the experimental period, the teeth upper airway was delineated as follows: were extracted without root damage and analysed • Superior margin: The line passing from the palatal with micro computed tomography. Each specimen plane (ANS to PNS) extending to the posterior was studied in 3D with specifically designed software wall of the pharynx. to measure the volume of each crater. • Inferior margin: Line passing from the anterior/ Results: It is expected that the results will indicate the superior edge of C4 to menton. relative severity of the root resorption associated with heavy jiggling forces; whether heavy horizontal and • Anterior margin: Line passing from the soft palate vertical jiggling forces have the same volume of root to menton. resorption and whether the direction of jiggling forces • Posterior margin: Posterior wall of pharynx. affects the distribution and location of resorption Results and discussion: The intra- and inter-reliability lesions. was high for both the airway volume and minimal cross-sectional area measurements. No systematic error was found between the data and method errors A new protocol to assess the upper airway in were minimal (less than 2%). The Houston reliability children coefficient and intra-class correlation was 0.99 - 1.0 Seerone Anandarajah,1 Yousef Abdalla,1 Raahib Dudhia,1 for each measurement. 1 1 2 Qingsong Ye, Andrew Sandham and Liselotte Sonnesen Conclusion: A new anatomical delineation for the 1 Department of Orthodontics, JCU, Cairns, Queensland, Australia assessment of the upper airway in children has been 2Department of Orthodontics, JCU, Cairns, Queensland, Australia and Department of Orthodontics, University of Copenhagen, Denmark proposed and was found to be reliable. This has the potential to standardise upper airway analysis Introduction: Few studies have performed in children and permit comparisons among future 3-dimensional analyses of upper airways in children. studies. However, these studies do not delineate the airway according to anatomical boundaries in children and/ or use soft tissue landmarks, which are easily mobile. Current evidence on the accuracy of Furthermore, no anterior or posterior anatomical interproximal enamel reduction in boundaries have been described. Consequently, orthodontics anatomical limits vary greatly among different research groups and impede unbiased comparisons. Mark Blandy Aim: To define new reliable upper airway margins Department of Orthodontics, James Cook University, Cairns, on cone beam computed tomography (CBCT) of Queensland, Australia children and validate the variables in the proposed Introduction: Interproximal enamel reduction (IPR) protocol. demonstrates an option for orthodontic space gain Materials and methods: Twenty-five scans were and can be considered a factor in borderline extraction randomly selected from a larger database cases. If an orthodontic treatment plan indicates IPR, containing CBCT scans of healthy children prior it is important to be able to complete the procedure by to commencement of orthodontic treatment (14 the removal of the exact amount required, particularly girls, 11 boys; Mean age 10.9 ± 2.5 years). The scans with the increasing popularity of digitally determined were evaluated with Dolphin Imaging® software treatment plans. However, is there any evidence in the by two observers, after training and calibration by literature to suggest that it is a procedure that can be the supervisor LS. Specific head positioning and accurately conducted with any degree of confidence? virtual orientation protocols were adapted. After the Aim: To review the evidence in an attempt to appropriate grey-scale threshold was established for determine how accurately IPR can be completed. each patient the volume and minimum cross-sectional area of the oropharynx, as defined by the authors, were Materials and methods: The literature was searched calculated. Each scan was reassessed two weeks later. using a key words search in Pubmed. No language or Intra- and inter-observer reliability was assessed. The time restrictions were set.

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Results: Two in vitro studies1,2 provided a true The effect of supra-physiological quantitative analysis of enamel reduction. One study concentrations of 25-hydroxy vitamin suggested no difference between desired and actual D3 and cytoskeletal compression in pre- enamel reduction except for the O-drive D30 system, osteoclasts: a pilot study which removed significantly more enamel than desired. While the other found that, in most cases, the B Griffin, Q Ye and K Miller actual amount of reduced enamel was less than the James Cook University, Cairns, Queensland, Australia intended amount of enamel reduction. Background: Under specific conditions pre-osteoclasts Discussion: The concept of interproximal reduction differentiate into osteoclasts, primarily facilitating (IPR) has evolved over time and relates back to the bone resorption. The expression of both RANK and perception that humans naturally wear interproximal M-CSF are required to permit osteoclastogenesis. enamel surfaces to avoid dental arch crowding. The Osteoclasts are known to have the ability to convert amount of IPR completed depends upon several inactive Vitamin D3 into the active form of the factors including enamel hardness, pressure applied, hormone in an autocrine fashion. They are also known hardness and particle size of the abrasives, and the to be sensitive to mechanical strain. However, little time spent undertaking the procedure. A review of the is known how inactive Vitamin D3 or mechanical literature has found that many studies have considered strain affects the differentiation of pre-osteoclasts into the surface characteristics after IPR, but limited mature osteoclasts. studies have focused on the quantity of enamel and Objectives: To investigate the expression of key the accuracy of the IPR. osteoclast-specific genes and proteins, following the Conclusion: IPR as a method for orthodontic space application of 25D3, combined with mechanical gain must be completed with accuracy, however compression, on pre-osteoclastic RAW264.7 cells, in there is limited evidence to support it as an accurate vitro. technique. This review has identified two in vitro studies that provide a true quantitative analysis of Methods: RAW264.7 cells were cultured with 25D3 enamel reduction. Future studies are needed to at concentrations between 0-500 nM, and subjected evaluate the accuracy of IPR by means of quantification to physiologically-analogous mechanical compression in an in-vivo setting. using the uni-axial four-point bending system, over a period of 1-5 days. Lysates were analysed for protein expression using immunohistochemical (IHC) References: staining and RNA relative abundance analysed using 1. Danesh G, Hellak A, Lippold C et al. Enamel surfaces following quantitative real-time polymerase chain reaction interproximal reduction with different methods. Angle Orthod 2007;77:1004-10. (qRT-PCR). 2. Johner AM, Pandis N, Dudic A et al. Quantitative comparison of 3 Results: The combination of supra-physiological enamel-stripping devices in vitro: How precisely can we strip teeth? Am J Orthod Dentofacial Orthop 2013;143:S168-72. concentrations of 25D3 (500 nM), and mechanical compression, leads to a significant increase in the relative abundance of both RANK and cFms across all time points, as well as sustaining elevated CYP27B1 expression over the 5-day study period. Increased expression of RANK, M-CSF and 25-Vitamin D3 hydroxylase proteins were confirmed by IHC staining. Conclusion: The combination of supra-physiological concentrations of 25D3 and mechanical compression acts synergistically to significantly elevate the expression of the enzyme responsible for the conversion of inactive Vitamin D3 to active vitamin D3, thereby confirming this autocrine mechanism in non-osteoclastically induced pre-osteoblasts. Furthermore, the same combination of interventions

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significantly upregulates the expression of both RANK may lead to reduced biofilm aggregation, and thus and M-CSF. Taken together, the results of this pilot reduced peri-implant inflammation. This may be a study suggests that the combination of 500 nM of factor in the operator choosing an appropriate OMSI 25D3, and mechanical strain, primes pre-osteoclasts system for use in their patients. to respond optimally to osteoclastogenic factors. Conclusion: Anodised titanium OMSI provided the This finding may provide useful insight into the smoothest surface finish. Further studies are needed to mechanism behind the enhanced effects of Vitamin determine if this had an effect in controlling biofilm D3 on orthodontic tooth movement. formation in orthodontics.

Surface roughness of orthodontic miniscrew References: 1. Miyawaki S, Koyama I, Inoue M et al. Factors associated with implants the stability of titanium screws placed in the posterior region for orthodontic anchorage. Am J Orthod Dentofacial Orthop Shaneel Shastri and Qingsong Ye 2003;124:373-8. Department of Orthodontics, School of Medicine and Dentistry, James 2. Chin MYH, Sandham A, de Vries J et al. Biofilm formation on Cook University, Cairns, Queensland, Australia surface characterized micro-implants for skeletal anchorage in orthodontics. Biomaterials 2007;28:2032-40. Introduction: Orthodontic miniscrew implants 3. Subramani K, Jung RE, Molenberg A et al. Biofilm on dental (OMSIs) have become popular in contemporary implants: a review of the literature. Int J Oral Maxillofac Implants orthodontics to attain anchorage. However, a high 2009;24:616. rate of failure of these devices has been one of the disadvantages. One of the potential areas for failure Accelerating orthodontic tooth movement that has been identified may be the aggregation with the aid of periodontal surgery – what of biofilm on these devices leading to peri- the practitioners are thinking implant inflammation.1 To date, the investigation into the surface characteristics of various OMSI Berna Kim, Wayne Sampson, Mark Bartold, Craig Dreyer systems has been limited.2 Surface roughness has been and Ian Parkinson identified as a factor involved in biofilm aggregation.3 University of Adelaide, Adelaide, SA, Australia Aim: This study aims to compare surface roughness of Introduction: There has been a revival of interest in OMSIs used in orthodontic practice. accelerating orthodontic tooth movement (OTM) Method and materials: Four OMSIs with various by inducing injury to the cortical bone. Coined the surface finishes available in the Australian market were term corticotomy, the procedure offers advantage to selected for the present study. They were: Ormco (V) adult patients whose bone metabolism can result in - Anodised titanium alloy, TOMAS (T) - machined extended treatment time. While the procedure may at titanium alloy, Leone (L) - Stainless steel, and Arhaus first seem radical and invasive, it has been refined for over 100 years, often reducing the length of treatment (A) - Anodised titanium alloy. Five implants from each by as much as a third. For the procedure to be group were selected and tested under atomic force successful, careful interdisciplinary management by microscopy (NT-MDT NTEGRA) and scanning orthodontists and periodontists is required. However, electron microscopy (Jeol JSM5410LV) around the little is known about knowledge of or attitudes toward head and neck region. Each implant was measured at the procedure in either Australia or New Zealand, or three random sites. Qualitative and quantitative data how often it is used. were collected for statistical analyses. Methods: A questionnaire was formulated and tested Results and Discussion: Anodised titanium was shown in a pilot study on post-graduate orthodontic and to have the smoothest surface finish of the four groups periodontic students at The University of Adelaide. (V and A Mean surface roughness of 39.54 nm As a consequence of the responses, the wording and 40.49 nm respectively), followed by machined was clarified and a sequence of questions modified titanium (Mean surface roughness 54.38 nm), and to produce the final form. Two questionnaires stainless steel (Mean surface roughness 65.60 nm). The were developed for specialist orthodontists and lower surface roughness around the head and neck of periodontists to reflect the different emphases and the OMSI, which is exposed to the oral environment were distributed at two separate conferences.

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Results and conclusions: The proportion of is essential in upregulating bone remodelling using a practitioners who had undertaken at least one buccally-directed orthodontic force. case per annum involving corticotomy was low, Methods: Thirty-six male Sprague Dawley rats aged with few orthodontists (11.5%) and periodontists between 6-8 weeks were randomly included in three (18.18%) reporting experience with the procedure. control groups (no surgery; flap surgery; corticotomy) The majority of orthodontists and periodontists and three tooth movement groups (tooth movement surveyed believed that more research is required on only; tooth movement and flap; tooth movement and the topic of corticotomy-facilitated OTM, and would corticotomy). Each group consisted of six rats and a not recommend the procedure to patients without fixed appliance exerted a buccally tipping force of 100 subjecting the technique to greater scrutiny. More than half of the sampled orthodontists indicated that g over seven days. Double bone labelling consisting of they would never recommend corticotomy-facilitated calcein and alizarin red was used for histomorphometric orthodontics to their patients. The minority who were analysis of the buccal alveolar bone turnover. Coronal willing to recommend the procedure would limit it sections of 5 μm thickness were chosen to study the to adult patients, ankylosed teeth, impacted canines effects of corticotomy on the buccal bony plate along and patients susceptible to root resorption. Over 90% the length of the root of the first maxillary molar tooth of sampled periodontists believe that there are side with histomorphometric analysis using a fluorescent effects associated with the corticotomy procedure. microscope. From each rat, five random slides were selected to quantify the mineral apposition rate at our defined region of interest. Dynamic response of the alveolar bone to Results: From the six groups tested, the tooth movement corticotomy-facilitated orthodontic tooth and corticotomy group had the highest mineral movement apposition rate (MAR) followed by tooth movement only, tooth movement and flap, corticotomy only, flap Berna Kim, Wayne Sampson, Mark Bartold, Craig Dreyer and Ian Parkinson only and control. There was a statistically significant University of Adelaide, Adelaide, SA, Australia difference between the tooth movement and flap group and tooth movement and corticotomy group Introduction: Due to case reports that demonstrate a (p < 0.05) but not between tooth movement only and dramatic reduction in time, interest in the topic of tooth movement and flap group. corticotomy-facilitated orthodontics has resurged. Despite most of these case reports showing a buccal Conclusion: When no orthodontic tooth movement movement of the teeth via the expansion of the (OTM) is involved, there is a trend of increasing arches, animal studies continue to use a mesially- MAR with the raising of a mucoperiosteal flap and directed movement for their investigative purposes. corticotomy procedure, but when OTM is involved, Furthermore, there are proponents who suggest that raising a flap does not significantly increase the MAR the raising of a mucoperiosteal flap should be sufficient beyond the levels of OTM. Therefore, we conclude to produce an up-regulation of bone remodelling. that injury to the cortical bone is essential in increasing The purpose of this study was to determine, using a the MAR and thus the OTM when a buccally-directed dynamic method, whether injury to the cortical bone force is applied to a tooth.

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