Early prevention of maxillary canine impaction: a randomized clinical trial.

OBJECTIVES: To investigate the effect of three interceptive measures (slow maxillary expansion (SME) with removable plates (1), extraction of both upper deciduous canines (DC) (2) and no intervention (3)) on maxillary canine (MC) position in patients with early mixed dentition (EMD) and lack of upper arch space. These three groups were additionally compared to a control group (4) with adequate upper arch space. NULL HYPOTHESIS: None of the studied strategies outperforms the others regarding improvement of MC position. TRIAL DESIGN: Four-arm parallel group prospective randomized controlled trial. PARTICIPANTS: Patients in EMD with at least one impacted MC, non-resorbed DC, and no crossbite. INTERVENTIONS: Patients with a lack of space were randomly distributed to protocols (1), (2), and (3). PRIMARY OBJECTIVE: To assess the change in MC position after 18 months follow up. SECONDARY OBJECTIVES: To assess canine eruption and need for orthodontic intervention within 18-60 month follow up. OUTCOME ASSESSMENT: Five variables defined canine position: sector, canine-to-midline angle, canine-to-first-premolar angle, canine-cusp-to-midline distance, and canine-cusp-to-occlusal-plane distance on two panoramic radiographs at 0 (T1) and 18 months (T2). Mean differences between groups were compared with linear mixed models, corrected for age and sex. RANDOMIZATION: The patient allocation sequence was generated by an electronic randomization list. BLINDING: The operator taking the measurements was blinded to the groups. RESULTS: Seventy-six patients were included (142 canines, mean age 9.2 years, 60.5 per cent male, mean follow up 1.9 years), 19, 17, 14, and 26 patients in groups 1-4, respectively. In absence of dental crossbite in patients with lack of space and impacted MC, SME improved the canine sector (P = 0.040), compared to no intervention (P = 0.028). Canine-to-midline angle and canine-to-occlusal-plane distance significantly decreased in all groups at T2. Extraction improved the canine-to-first-premolar angle at T2 more than other strategies in EMD (P = 0.015-0.000). CONCLUSIONS: Early SME improves the canine sector and reduces the need for major orthodontic intervention in the long term. Taking a first panoramic radiograph in EMD allows timely intervention in case of MC impaction. TRIAL REGISTRATION NUMBER: NCT05629312 (Clinical Trials.org). Trial status: follow up ongoing.

Dental and Craniofacial Characteristics in Patients With 14Q22.1-Q22.2 Deletion: A Case Series.

This case series is a follow-up report focusing on dental and facial characteristics in patients with a rare microdeletion in chromosome 14q22.1-q22.2. Usually, these patients have severe ocular, brain, and digital abnormalities. However, this case series shows that clinical presentation can be mild. Four relatives spanning 3 generations were diagnosed with a familial autosomal dominant 2.79 Mb microdeletion in chromosome 14q22.1-q22.2. Genetic screening was done by the Bacterial Artificial Chromosome array-comparative genome hybridization and was confirmed by the fluorescence in situ hybridization technique. Dental and craniofacial data were collected from medical files, clinical examinations, clinical photos, panoramic and cephalometric radiographs, and dental casts. Written informed consent for scientific use was obtained for all family members. No larger syndrome could be identified. All cases had similar facial red flag characteristics, consisting of a long face with retrognathia and open mouth relation, associated oral clefts in varying degrees, depressed nasal bridge, delayed tooth development, hypertelorism, and low-set angular ears. The dental casts showed a distal molar occlusion and a lack of space in the dental arches. Developmental delay was noted together with limb defects such as poly- and syndactyly. Microphthalmia and hearing loss were present in the most severe cases. This rare congenital disorder, associated with facial dysmorphia, oral clefts, and tooth agenesis, can remain undiagnosed until adulthood. A family history of short stature, developmental delay, poly- or syndactyly, and micropthalmia are suggestive features. Similar reports help to raise awareness among dental practitioners, leading to an early genetic diagnosis.

Development and validation of the autotransplanted maxillary canine radiological index.

The purpose of this study was to propose and validate an index evaluating 2D and 3D radiographic variables of autotransplanted maxillary canines. Setting and sample population are from the Department of Oral and Maxillofacial Surgery at University Hospitals Leuven. Eight oral-maxillofacial surgeons rated 12 autotransplanted maxillary canines and adjacent bone using 11 rating variables. A new autotransplanted maxillary canine radiological index (AMCRI) was proposed. It consisted of 11 variables. These variables were based on 2D (intraoral) and 3D Cone Beam Computed Tomography (CBCT) radiographs. Intraclass correlation coefficient (ICC) and Fleiss's kappa statistics were performed to analyze intrarater and interrater agreement. Considering cumulative assessment of the AMCRI, the mean ICC value for the interrater agreement of the eight examiners was 0.94, representing an excellent agreement. Intrarater agreement was 0.91. The AMCRI is an objective tool in rating radiological outcome of autotransplanted canines and adjacent bone, when compared with the contralateral canine.

Development and validation of the Maxillary Canine Aesthetic Index.

Aesthetic appraisal is rarely included in the objective assessment of outcome studies of impacted maxillary canines treatment. The present study aimed to validate a new index for assessing the aesthetic appearance of maxillary canines and adjacent soft tissues. The Department of Oral and Maxillofacial Surgery at University Hospitals Leuven. Four oral-maxillofacial surgeons, two orthodontists, two prosthodontists, and two lay persons rated 11 maxillary canines and adjacent soft tissues according to the new index. Each of the examiners repeated the examination three times with a 2-week interval. Twelve relevant aesthetic variables were selected on the basis of the anatomic form, color, and surface characteristics of the canine crown and on the basis of the anatomic form, color, and surface characteristics of the adjacent soft tissues. Intraclass correlation (ICC) coefficient and Fleiss' kappa statistics were performed to analyze the intrarater and interrater agreement. The index proofed to be a reliable assessment tool. Considering the cumulative assessment of the Maxillary Canine Aesthetic Index (MCAI), the mean ICC value for the interrater agreement of the 10 examiners was 0.71, representing a good agreement. Intrarater agreement ranged from 0.10 to 0.91. Interrater agreement (Fleiss' kappa statistics) calculated for each variable ranged from 0.08 to 0.98. The MCAI is a tool in rating aesthetic outcome of impacted canine treatment and adjacent soft tissues. The MCAI can be used to evaluate the aesthetic outcome after surgical exposure or transalveolar transplantation of maxillary canines.

Relationship between buccal bone and gingival thickness revisited using non-invasive registration methods.

OBJECTIVE: To determine the relationship between buccal bone and soft tissue thickness at teeth in the premaxilla by means of non-invasive registration methods. MATERIALS AND METHODS: Buccal bone thickness at central incisors, lateral incisors and canines was measured at five reference points (1-5 mm from the top of the alveolar crest) on CB-CT scans of 21 patients. The corresponding buccal gingival thickness was measured by the use of an ultrasonic device. Spearman's correlation coefficient was calculated to assess the correlation between buccal bone and soft tissue thickness at each tooth type. RESULTS: Mean buccal bone thickness (SD) at central incisors, lateral incisors and canines was 1.07 mm (0.34 mm), 1.16 mm (0.54 mm) and 0.98 mm (0.37 mm), respectively. For central incisors, 68% of all sites had a thickness <1 mm and 32% had a thickness between 1.0 and 2.0 mm. At lateral incisors, 44% demonstrated buccal bone thickness between 0 and 1.0 mm, 48% between 1.0 and 2.0 mm and 8% ≥2 mm. For canines, 57% of the sites were <1 mm thick; 41% were between 1.0 and 2.0 mm thick, and 2% demonstrated ≥2 mm thickness. Mean gingival thickness (SD) at central incisors, lateral incisors and canines was 1.37 mm (0.32 mm), 1.33 mm (0.32 mm) and 1.08 mm (0.25 mm), respectively. The correlation between buccal bone and soft tissue thickness was moderately positive (ρ = 0.406; P < 0.001). CONCLUSIONS: A thin buccal bone wall (<1 mm) may be expected in over half of the central incisors and canines. The correlation between buccal bone and soft tissue thickness was moderately positive.