Influence of repeat surgery on treatment time in the interdisciplinary management of impacted maxillary canines: A retrospective cohort study

Factors Associated With Successful Surgical Exposure of Impacted Maxillary Canines

PURPOSE

Impacted maxillary canines occur in up to 3% of the population and their eruption is of great importance in establishing, maintaining the shape, aesthetics, and function of the dental arch. Hence, surgical exposure of canines for the purpose of aligning them is a common surgical procedure. This study identifies the frequency and the statistically significant factors associated with successful surgical exposure of impacted maxillary canines and the relative risk factors for repeat surgery.

METHODS

This is a retrospective cohort study of 182 patients who underwent surgical exposure of impacted maxillary canines and orthodontic alignment, over a 5-year period between 2014 and 2018. The variables recorded and analyzed included demographics (age and gender), type of surgery (closed or open exposure), grade of surgeon, and radiographic features on orthopantomogram (canine overlap of adjacent tooth root, vertical canine crown height, canine angulation to midline, position of canine root apex). Outcome data recorded were successful surgical exposure and orthodontic alignment and the need for repeat operation or surgical removal due to ankylosis. The data were analyzed to identify the statistically significant correlates of successful surgical exposure and the relative risk factors associated with repeat surgery.

RESULTS

A total of 182 patients and 232 bone-impacted maxillary surgical canine exposures were analyzed, as 50 patients had bilateral impaction. Mean age was 15 years (range = 10-38 years), with 122 (67%) female to 60 (33%) male ratio. Total of 222/232 (96%) impacted maxillary canine teeth were successfully surgically exposed and 10/232 (4%) required re-exposure surgery. Correlates of successful surgical exposures were open exposure technique (P < .002) and reduced distance of vertical canine crown height from alveolar bone margin (P < .033). Relative risk factors for repeat surgery were increased age, male, closed surgical exposure, grade of surgeon, central impaction, increased overlap of adjacent root, increased vertical height, increased angulation to midline, canine apex position above second premolar and procedure done under local anesthetics.

CONCLUSIONS

This is the largest impacted maxillary canine study to date which has identified the factors that result in successful surgical exposure, hence allow selection of the patients most suitable for this treatment. Secondly, patients with relative risk factors for repeat surgical intervention may be consented appropriately, triaged for a closer orthodontic follow-up and prioritized for surgery to reduce overall treatment time.

Predictors of treatment decisions made by adult orthodontic patients presenting with unerupted permanent teeth

OBJECTIVE

Unerupted permanent teeth are amongst the most commonly occurring dental anomalies in adults and present unique treatment challenges. The aim of this retrospective study was to (1) identify the prevalence of adult patients with unerupted teeth attending a multidisciplinary clinic and (2) to identify predictors (age, gender, incisor and skeletal classification) which influence the patients treatment decision.

MATERIAL AND METHODS

Consecutive adult patients with unerupted permanent teeth attending the Joint Orthodontic-Restorative clinic were identified. Study variables were collected using a prespecified data collection form. Descriptive statistics were employed; Fisher's exact test was used to detect associations between variables and treatment decision outcome. Ordinal logistic regression derived multinomial regression relative risk ratios (RRR) and 95% confidence intervals (CI) were calculated for the effect of age, gender, incisor and skeletal classification on treatment decision/outcome.

RESULTS

Sixty-six patients with impacted teeth were identified from a sample of 483. The prevalence of adults with unerupted teeth was 13.7%. The mean age was 30.7 years (SD 11.2). The majority of the sample had a Class I incisor relationship (54.6%) or Class I skeletal base relationship (54.6%), and the most common distribution of impacted teeth was a single unerupted upper right canine (34.9%). Orthodontic treatment (non-extraction or extraction basis incorporating the alignment or removal of impacted teeth) and restorative treatment only were equally favoured. Factors including age, gender, incisor and skeletal classification did not appear to influence or predict the final treatment decision.

CONCLUSIONS

In this sample, adults presenting with impacted teeth favoured certain treatment modalities: orthodontic treatment only and restorative treatment only. Factors such as age, gender, incisor and skeletal classification did not influence the outcome.

Multidisciplinary Management of a Severe Maxillary Midline Diastema: A Clinical Report

A maxillary midline diastema (MMD) is a common form of incomplete occlusion and often is a primary complaint of patients during dental consultations. MMD is considered to be a multifactorial phenomenon and can therefore be best restored with a multidisciplinary approach. This clinical report presents a multidisciplinary approach to the management of a 4.0-mm MMD by using limited orthodontics combined with periodontal and prosthodontic treatments.

[Multiple uses of skeletal anchorages: taking advantage of mini-screws to improve aesthetics with active and passive appliances]

INTRODUCTION

The main causes of failures in canine traction are anchorage defects, incorrect direction of force, uncontrolled forces. An adolescent female (10 years, 9 months) presents with two included canines on the maxillary arch, in a palatal position and her lateral incisors (12 and 22) are microdontic. Two mini-screws are inserted on the palate, in a mesial position to 16 and 26 to secure the traction of 13 and 23; in general, braces are bonded after this first step. After debonding, mini-screws remain to help stabilize the palatal plate during the retention period and to avoid unaesthetic metallic wires and hooks which sometimes cause occlusal interferences.

DISCUSSION

The alternatives are discussed: Ballista spring, mini-screw inserted in the palatal suture, Nance appliance… Conclusion: The multi-use of temporary anchorage devices during traction of palatally impacted canine(s) (especially in the case of bilateral inclusions) offer new alternatives by securing the canine displacement, eliminating almost all of the patient's compliance (no loss of sagittal anchorage). This type of small appliance increases the patient's comfort and decreases the complexity of activations. The global duration of treatment with braces can be decreased if no braces are needed during the first steps, and then retention can be more effective and more aesthetic, especially during smiling.