Management of Unerupted Anterior Teeth: An Audit of Treatment Outcomes

Introduction: Anterior teeth are valuable for aesthetics, speech and mastication. Their absence, impaction, and/or delayed eruption create significant distress often leading to early presentation to the dental office. This study presents an audit of the management of impacted anterior teeth that presented at a tertiary level dental clinic. The periodontal outcomes of the aligned teeth were also reported. Methods: This is an observational study spanning a nine-year period. Demographic data, clinical presentation, as well as post alignment dental and periodontal status of the impacted teeth were assessed. Data were analysed using the Statistical Package for Social Sciences (SPSS) version 26. Fisher’s exact test and paired samples T-test were used for categorical and continuous variables respectively. Significance was set at P < 0.05. Results: Twenty-eight (1.76%) cases presented with failed eruption of 32 anterior teeth were observed during the period under review. Eight patients were treated by extraction, orthodontic treatment, and space closure or prosthetic replacement, with a mean treatment time of 2.83 ± 2.66 years. Thirteen patients completed treatment by orthodontic alignment with mean alignment time of 1.4 ± 1.5 years and treatment time of 3.6 ± 2.5 years. Average loss of root length observed was 1.5mm. There was significant difference in the post-operative root length of aligned teeth compared to their normal antimeres (p < 0.005). Conclusion: Patients with impacted anterior teeth presented later than was beneficial for spontaneous alignment of their teeth. The average 1.5mm loss of root length observed was not detrimental to the anatomical retention or function of the aligned teeth. There is need for more enlightenment with regards to early presentation for dental problems to avoid expensive and time-consuming treatments.


Introduction
The anterior teeth, consisting of the incisors and canine bilaterally, are often referred to as "the social six". These are the most visible teeth in the oral cavity and are vitally important for speech and aesthetics, as well as mastication. 1,2 The absence, impaction, and/or delayed eruption of these teeth create significant aesthetic and psycho-social distress both to the individual as well as their care givers, and thus give rise to early visits to the dental clinics. [2][3][4][5] The canines are reported to be the most prevalent impacted teeth in the anterior region, occurring in 2.0-6.0% of the global population, 4,[6][7][8][9][10] closely followed by the central incisors which are impacted in 0.06-3.00% of global population. 2,4,8,[10][11][12][13] A previous Nigerian study reported that 1.7% of their clinic attendants presented with anterior teeth impaction (1.3% central and 0.4% lateral incisors) in a two year review. 14 Impacted central incisors are the earliest to be detected because of their early eruption time. 6,8,15 Impaction of lateral incisors are however rare. 3 While canine impaction appears to be more prevalent among females, 7, 9, 16, 17 central incisor impactions appear to have a higher male prevalence, 3 although absence of gender predilection has also been reported. 13 Unilateral impactions are more prevalent than bilateral 3, 7, 17 and maxillary impactions more common than mandibular. 16,17 Tooth impaction is caused by supernumerary teeth or odontoma, trauma which causes crown/root dilaceration or displacement of the tooth bud. Impaction may also be caused by soft or fibrous tissue interference as well as odontogenic tumours and cyst. 2,4,12,[18][19][20] The treatment of impacted teeth includes the extraction of obstructing structure for spontaneous realignment, if the condition is detected early. Extraction-replantation or autotransplantation of the tooth with endodontic treatment, definitive extraction with prosthetic replacement, or surgical exposure for orthodontic alignment are other treatment options. 2,5,6,21 The last treatment can be achieved using the open or closed flap traction technique, 19 with the latter reported to give clinical outcome similar to that obtained during natural eruption. 6,22 The choice of treatment is determined by various factors such as the age and stage of dental development of the patient, the specific tooth, depth of impaction, orientation or lie of the tooth, space availability, patient's expectation and financial capability, as well as the expertise of the orthodontist. 6,19,23 Possible negative outcomes of orthodontic treatment of such impacted teeth include root shortening, increased crevicular depth, abnormal gingival contour, loss of keratinized gingiva and/or clinical attachment, increased clinical crown length, root exposure, and in extreme cases, loss of tooth vitality. 7,12,18,19,23 Considering the cost and time implication of orthodontic alignment of impacted teeth, these must be thoroughly discussed with the patient and steps must be taken to avoid them.
This study presents an audit of patients treated for the impaction of anterior teeth and the post alignment periodontal outcomes as experienced in a tertiary level orthodontic clinic in South-Western Nigeria.

Methods
This is a nine-year retrospective observational study of dental outpatients. Ethical approval for this study was sought and obtained from the Institutional Review Board (UI/EC/16/0177).

Patients treated by orthodontic alignment
Eighteen patients were in this category, 17 (94.4%) of whom had been successfully treated to the alignment stage. Four (23.5%) of these 17 who did not complete or had not completed the full orthodontic treatment for various reasons (see Figure 1) as well as one whose parent did not present for the extra post treatment periapical radiograph were excluded from the clinical outcome assessment.

Clinical outcomes assessment
The mean alignment time was 1.4 ± 1.5 years and for the 13 who completed treatment, the mean treatment time was 3.6 ± 2.5 years. There was no loss of vitality of any tooth. There was no significant difference in the outcome variables accessed between the orthodontically aligned teeth and their normal counterparts, except the post-operative root length (p<0.005). This is presented in table 2. Although the gender prevalence for impacted canines and central incisors in our patient population is similar to the globally reported trend, 3,7,9,16 it was not a significant finding in this study. This may be because this population of patients presented an almost equal proportion of canine and central incisors that are impacted with a slightly higher number of central incisors, compared to a global trend that has always significantly favoured canine prevalence. [6][7][8] While the clinical value of the gender prevalence of impacted anterior teeth here is irrelevant, the overall higher central incisor presentation may underscore the higher aesthetic value placed on the central incisor over canines.

Conclusion
There is a relatively low prevalence of impacted anterior teeth among patients seen at the clinic.
Patients presented later than is beneficial for spontaneous alignment of their teeth and treatment abandonment as a problem is highlighted. There is need for more oral health enlightenment with regards to early presentation for dental problems to avoid expensive and timeconsuming treatments.