DOI: 10.1051/odfen/2018053 J Dentofacial Anom Orthod 2018;21:204 © The authors Periodontal approach of impacted and retained maxillary anterior teeth N. Henner1, M. Pignoly*2, A. Antezack*3, V. Monnet-Corti*4 1 Former University Hospital Assistant Periodontology – Private Practice, 30000 Nîmes 2 University Hospital Assistant Periodontology – Private Practice, 13012 Marseille 3 Oral Medicine Resident, 13005 Marseille 4. University Professor. Hospital practitioner. President of the French Society of Periodontology and Oral Implantology * Public Assistant for Marseille Hospitals (Timone-AP-HM Hospital, Odontology Department, 264 rue Saint-Pierre, 13385 Marseille) – Faculty of Odontology, Aix-Marseille University (27 boulevard Jean-Moulin, 13385 Marseille) ABSTRACT Treatment of the impacted and retained teeth is a multidisciplinary approach involving close coopera- tion between periodontist and orthodontist. Clinical and radiographic examination leading subsequently to diagnosis, remain the most important prerequisites permitting appropriate treatment. Several surgical techniques are available to uncover impacted/retained tooth according to their position within the osseous and dental environment. Moreover, to access to the tooth and to bond an orthodontic anchorage, the surgical techniques used during the surgical exposure must preserve the periodontium integrity. These surgical techniques are based on tissue manipulations derived from periodontal plastic surgery, permitting to establish and main- tain long-term periodontal health. KEYWORDS Mucogingival surgery, periodontal plastic surgery, impacted tooth, retained tooth, surgical exposure INTRODUCTION A tooth is considered as impacted when it eruption 18 months after the usual date of has not erupted after the physiological date eruption, when the root apices are edified and its follicular sac does not connect with and closed. the oral cavity. Impacted teeth can be locat- An impacted tooth must be differentiat- ed in a bone crypt, more or less at the level ed from an enclosed tooth. The latter has of the maxilla or mandible. Clinically, teeth not erupted but is connected with the oral are deemed as impacted in the absence of cavity. Address for correspondence: Nicolas Henner – 4 Square de la Bouquerie – 30000 Nîmes Article received: 19-10-2017. E-mail: [email protected] Accepted for publication: 23-11-2017. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1 Article available at https://www.jdao-journal.org or https://doi.org/10.1051/odfen/2018053 N. HENNER, M. PIGNOLY, A. ANTEZACK, V. MONNET-CORTI Impacted teeth can be left in place The objectives of surgical release are when there is still a chance they will as follows: erupt (immature tooth with unedified apices). Anatomical, physiological, or – direct access to the clinical crown; pathological obstacles prevent their – osseomucosal release sufficient eruption. If a retained tooth matures, it for bonding of orthodontic lock; becomes an impacted teeth. – tissue movement to recreate nor- A tooth is considered dystopic or ec- mal periodontal anatomy normal topic when it is in the wrong position, and/or compatible with preserva- outside its eruption path. tion of periodontal health; The periodontal approach for im- – emergence of the tooth in a dys- pacted and retained teeth, also called topic site19. surgical release, and involves the management of bone, connective, and Knowledge of the validity and pres- epithelial tissues. It uses certain perio- ence of keratinized tissue around teeth dontal plastic surgery techniques that during eruption, growth, puberty, and can be adapted to reach the impacted orthodontic treatment leads to many teeth and, at the same time, to adjust periodontal plastic surgery interven- the marginal periodontium. tions being proposed in children and adolescents. IMPACTED AND RETAINED TEETH Impaction can be unilateral or bilateral. of the impacted maxillary canines are In the order of frequency, the most vestibular, 40.5% are palatal, and 14.3% commonly impacted teeth are the third are transalveolar39. molars, then the maxillary canines, the The prevalence of impacted canines maxillary central incisors, the second is 1%–2% of the population11,13. Finally, mandibular premolars, the mandibular 90% of the impactions are covered canines, and the first molars11,18,23,40. mainly with soft tissues24. Impactions more frequently affect the female population (two-third of all Etiology impactions) than men, especially for the maxillary canines6,30,34. Numerous etiological factors, whether According to some authors, palatal im- general, regional, or local, may explain paction of the maxillary canine is more the impaction of certain teeth from the frequent than vestibular inclusion (85%) anterior sector of the maxilla. They are and 8% of these cases are bilateral.7. related to two etiological theories: ge- However, a more recent study using netic theory and guiding theory. data obtained by cone-beam comput- The etiology of inclusions is multifac- erized tomography shows that 45.2% torial.4 2 Henner N., Pignoly M., Antezack A., Monnet-Corti V. Periodontal approach of impacted and retained... PeriodontaL approach OF IMpacted AND retained MAXILLary ANTERIOR teeth Primary causes A supernumerary teeth are formed from an aberrant bud arising from a • Genetic36 proliferation of the tooth or a bud split- There seems to be family predispo- ting into two halves that evolve sepa- sitions to impaction. In fact, families rately. The supernumerary tooth can be were found in which the prevalence distinguished from normal (eumorphic) of an impacted maxillary canine was or abnormal (dysmorphic: conical, rice- 4.9%, which is 2.5 times greater than shaped) forms. Only 25% of them erupt in the general population. in the oral cavity. In 80% cases, super- numerary teeth have a median position Major syndromes such as Gardner’s between the maxillary central incisors: syndrome, cleidocranial dysostosis, they are then called “mesiodens.” Down syndrome, Crouzon’s syndrome, labioalveolopalatal clefts, and Yunis– Odontoma is a benign odontogenic tu- Varon syndrome are usually associated mor composed of tissues involved in od- with multiple inclusions. ontogenesis. A compound odontoma is • Endocrine deficiency an amalgamation of small odontoid struc- Certain disorders such as hypothy- tures conforming to normal odontogen- roidism and vitamin A, C, D deficien- esis. Complex odontoma associates cies cause growth disruption and may anarchically aggregated dental tissues. be the cause of dental retention and Its clinical manifestation is very discreet impaction26. because it is painless to the touch and there is no cortical deformation. It is • Irradiation often only discovered by chance. Its loca- • Labiopalatal cleft43 tion is maxillary in 60% cases, and more frequently in the anterior region37. Dental root development abnormality Whether for odontomas or supernu- and isolated dysmorphia can affect the merary teeth, the absence of symp- coronal or root part of the tooth, thus toms makes it impossible to suspect compromising its eruption. It can be their presence. They are diagnosed congenital as a result of a temporary through systematic and radiological tooth trauma. screening. Rapid management often helps to remove these obstacles that • Supernumerary teeth and odonto- immobilize permanent teeth or diverts ma (Fig. 1) them from their eruption path. Figure 1 Presence of an odontoma leading to a delayed eruption of 11 and a delayed rhizalysis of 51. J Dentofacial Anom Orthod 2018;21:204 3 N. HENNER, M. PIGNOLY, A. ANTEZACK, V. MONNET-CORTI • Dentomaxillary disharmony (rather It may be possible to establish a link for vestibular inclusions) between the frequency of impaction of maxillary canines—the second most A lack of space available on the arch frequently impacted tooth—and the can result from a primary etiology, either agenesis frequency of the maxillary skeletal (brachygnathia) or dental (mac- lateral incisors—the second most fre- rodontia). Because of the lack of avail- quent cause of agenesis. able space, associated with or without In case of agenesis of the lateral dental congestion, the tooth remains im- incisors, the impaction of the ipsilat- pacted in a more or less distant position eral canine is usually palatal. Indeed, from the occlusion plane, inducing risks a palatal trajectory of the eruption of of root resorptions for adjacent teeth. the maxillary canines coincides more with an excessive amount of develop- mental space or a lack of guidance of • Delay or absence of root formation the lateral root rather than a lack of of the tooth space37. • Differential growth between pre- maxillary and maxillary (for the • Trauma (maxillary deciduous inci- maxillary canine) sors cause 15% cases of central • Maxillary brachygnathia maxillary incisor impactions) • Transverse deficiency of the anteri- 33 • Decrease in the perimeter of the or maxillary region arch Secondary causes Premature extraction of deciduous teeth causes the adjacent teeth to mi- • Loss of guidance via agenesis of grate and may block the path of the un- the lateral incisor14,36,38. derlying germ, preventing its eruption and placement on the arch. Proximal tooth agenesis sometimes induces a dental impaction via the • Root malformation loss