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Maxillary Lateral Incisor Agenesis: a Review of Literature Rehan Qamara, Annam Imtiazb, Muhammad Kamranc

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Maxillary Lateral Incisor Agenesis: a Review of Literature Rehan Qamara, Annam Imtiazb, Muhammad Kamranc REVIEW ARTICLE POJ 2012:4(2) 69- 72 Maxillary lateral incisor agenesis: A review of literature Rehan Qamara, Annam Imtiazb, Muhammad Kamranc Abstract Introduction: Tooth agenesis is defined as congenital absence of one or more teeth in primary or permanent dentition and is a common oral variation that affects a large population group. Among the missing one’s, maxillary lateral incisor is more frequent causing esthetic and functional impairments in the affected individual. It might be associated with systemic problems, syndromic conditions or other oral anomalies. Management of missing lateral incisors involves a multi-disciplinary approach for rehabilitation of impaired esthetics and function. The current literature review is offered to highlight the important characteristics of this anomaly for better management of such patients. Material and Methods: Several electronic databases were searched. Hand searching was done to short list the relevant articles. A total of 63 studies were retrieved out of which 48 most relevant studies were selected for the review. Results: maxillary lateral incisor agenesis is a common dental anomaly and has been reported to affect a wide group of populations. It can be unilateral or bilateral and females are more prone to be affected than the males. Conclusions: agenesis of maxillary lateral incisors is a common oral variation of either genetic or environmental origin. A comprehensive evaluation of the anomaly would be helpful to develop significant clinical management of the affected patients. Keywords: Tooth agenesis; hypodontia; maxillary lateral incisor; congenitally missing teeth Introduction clinicians include regaining of the space of missing tooth followed by prosthetic ental agenesis is defined as congenital replacement, auto transplantation of D absence of one or more teeth in primary developing premolar and space closure with or permanent dentition.1It is also known as substitution of canine.8,9 The aim of current hypodontia and is one of the most frequently review of literature was to appraise the data encountered of all oral variation that affects a related to prevalence, etiology and large population.2,3 Epidemiological studies management options for congenitally missing reveal make that one of the most common maxillary lateral incisors. congenitally missing tooth is lateral incisor in maxilla causing esthetic and functional Material and Methods impairments in the affected individual.4,5 It The present review of literature was done might be associated with Non-syndromic based on the guidelines given in Pakistan systemic problems, syndromic conditions or Orthodontic Journal. Internationally other oral anmolaies.6 Management of published research literature, review articles missing lateral incisors is a challenging and relevant citations were included. After procedure that involves a multi-disciplinary the electronic literature search, a hand search approach for rehabilitation of impaired of key orthodontic journals was undertaken esthetics and function.7 The most common to identify recent articles. The review was treatment approaches advocated by the restricted to articles dealing with dental aCorresponding Author; BDS, FCPS, Associate Professor, agenesis and particularly agenesis of University College of Dentistry, The University of Lahore. Email: [email protected] maxillary lateral incisors. Exclusion criteria b,cBDS, Resident, Dept. of Orthodontics, University College of included articles that did not follow the Dentistry, The University of Lahore objective of this review. 69 POJ 2012:4(2) 69- 72 Resul ts population.29,30 In primary dentition, the A broad search of published articles (The incidence for missing maxillary lateral incisor Angle Orthodontist, American Journal of in Caucasian population is 50%.31,32 Orthodontics and Dentofacial Orthopedics, Females are more affected than males20,33,34 British Dental Journal, European Journal of and bilateral absence is more frequent than Orthodontics, Journal of clinical pediatrics, unilateral.l3,35 In cleft patients, the most Journal of Oral Pathology) was done using frequent missing tooth reported is maxillary both the electronic database and hand lateral incisor.36 searching. A total of 63 studies were retrieved Accurate diagnosis of a missing tooth initially. 48 studies having close relevance to requires clinical and radiographic the current study objective were used to examinations and sometimes dental casts to convey the review of literature for the distinguish whether the tooth is extracted agenesis of maxillary lateral incisors. impacted or congenitally absent.37,38 A variety of esthetic problems are associated Discussion with maxillary lateral incisor agenesis. This Agenesis of teeth can be due to genetic or includes median diastema, spacing between environmental factors.10 In non syndromic permanent incisor and canine, mesial agenesis, gene mutations are said to be the migration of canines, midline shift in case of 39 cause. The mutations in genes responsible for unilateral missing tooth. Over-retention of tooth development are marked as PAX9, maxillary deciduous lateral incisor and MSX1, and AXIN2.11 Among these, MSX1 is canine, ectopically erupted canines, absence usually related to congenitally missing third of canine eminence, asymmetric loss of molars, second premolars, maxillary first primary teeth, dental asymmetries are premolar and incisors.12 significant apparent factors that are useful for 40 The syndromic type dental agenesis is diagnosing the entity. commonly exhibited in ectodermal dysplasia Confirmed diagnosis of a missing tooth and various orofacial clefting syndromes.13-15 requires radiograph like periapical view or an Several orthodontists claim that susceptibility OPG. Among them, tomography is the most of its agenesis increases since lateral incisor is reliable method for diagnosing congenitally 41 located in areas of fusion of facial processes.16 missing teeth. Among the environmental factors, the close Management of missing maxillary lateral related ones are trauma, infections, chemical incisors is challenging process for re- agents and radiations.17-19 establishment of esthetics and function of the The review of literature demonstrates that if affected individuals. The most appropriate more than one or two teeth are misaiming, the approaches as reported in the literature most frequent one is lateral incisor.20 The namingly are i) Regaining of space by prevalence of maxillary lateral incisor orthodontic therapy ii) Autotransplantaion of agenesis in the permanent dentition shows premolars iii) Orthodontic space closure. great variation among different population groups and ranges between 1-3%.21 In 1) Regaining of space by orthodontic Caucasian population it prevails up to therapy: this approach is aimed to 20%.22,23 Among various ethnic groups, the provide adequate space for replacement agenesis of maxillary lateral incisor is most of missing tooth. Space opening can be frequent in Iranian and Brazilian achieved by closing the midline diastema population,24,25 second most frequent is and retracting the ectopically erupted 41,42 Indian, Jordanian and Danish,26-28 and third canines. The amount of space required most affected are Norwegian and Kenyan can be determined by application of 70 POJ 2012:4(2) 69- 72 golden proportions, measuring the Bolton following this method would result in discrepancy and the missing lateral anterior group functioning during lateral incisor is then replaced to the best of its excursions instead of canine guided esthetic and functional demand using a occlusion. This occlusal scheme is also variety of alternatives as per patients acceptable and considered stable by choice and socioeconomic status. These several school of thoughts.48 include removable denture, fixed cantilever bridge, fiber reinforced Conclusions composite fixed partial dentures, resin Maxillary lateral incisor is among one of the bonded fixtures, or by implant supported most common congenitally missing teeth that restoration.43 occurs either due to genetic or environmental 2) Autotransplantaion of premolars: disturbances. Management of missing lateral Autotransplantaion of premolars at incisors is a challenging and complex process maxillary lateral incisor position is that involves a multidisciplinary approach in suggested when 2/3rd root of premolar order to restore the esthetics and function. roots have developed so that A high quality perspective of this entity autotransplanted teeth can achieve might be helpful in developing meaningful functional adjustment. The success rates clinical management of affected patients. of autotransplantaion range from 79-90% as reported in the literature.44 After three months of successful autotransplantaion, References the crown of premolar is modified to bear 1. Hobkirk JA , Goodman JR, Jones SP. Presenting a resemblance with the maxillary lateral complaints and findings in patient attending hypodontia clinic. Br Dent J 1994;177:337-39. incisor both esthetically and 2. Dhanrajani PJ. Hypodontia: etiology, clinical functionally.45 features, and management. Quintessence Int. 3) Orthodontic space closure: It is best 2002;33:294-302. indicated for patients presenting a class II 3. Zhu JF, Marcushamer M, King DL, Henry RJ. Supernumerary and congenitally absent teeth: a malocclusion with noncrowded lower literature review. J Clin Pediatr Dent. 1996;20:87-95. arch, class I malocclusion with sever 4. Polder BJ, Van't Hof MA, Van der Linden FP, crowded upper lower arches where
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