Unusual Supernumerary Teeth and Treatment Outcomes Analyzed for Developing Improved Diagnosis and Management Plans.

PURPOSE: Supernumerary teeth (SNTs) are teeth or tooth-like structures that have erupted or might erupt in addition to the 20 primary or 32 permanent teeth. The simultaneous presentation of multiple SNTs, syndrome-related multiple SNTs, SNTs inside the maxillary sinus and treatment outcomes were analyzed to develop improved diagnosis and management plans. PATIENTS AND METHODS: This retrospective study reviewed the medical records of National Cheng Kung University Hospital patients who had undergone surgical intervention with general anesthesia between February 2014 and September 2018; analyzed panoramic radiographs and cone beam computed tomography scans of their multiple SNTs; and used descriptive statistics to discuss treatments and relative complications, especially of unusual SNTs. RESULTS: The records of 165 patients (127 male and 38 female patients; mean age, 12.4 years) with 241 SNTs (120 patients had 1 SNT, 35 had 2 SNTs, 3 had 3 SNTs, 2 had 4 SNTs, 2 had 5 SNTs, 2 had 6 SNTs, and 1 had 12 SNTs) were reviewed. There were 185 SNTs in the maxilla and 56 in the mandible; 153 were mesiodens and 115 were inverted; 142 were asymptomatic and 137 were conical; and 228 were fully impacted and 210 were partial roots. Two patients had SNTs inside the maxillary sinus, and one had 5 SNTs and Marfan syndrome. Two patients had postoperative lip or chin paresthesia, and two had postoperative sinusitis. CONCLUSIONS: Patient demographic variables provided useful epidemiologic information. We recommend panoramic radiographs or cone beam computed tomography for managing patients with possible multiple SNTs and for extracting SNTs.

Plane-to-plane analysis of mandibular misalignment in patients with facial asymmetry.

INTRODUCTION: Little is known regarding how the mandible rotates in facial asymmetry. The purpose of this study was to study mandibular misalignment with a new plane-to-plane analysis method in patients with facial asymmetry. METHODS: Optimal symmetry planes (OSPs) were generated by computing the greatest count of paired voxels on opposing sides of the computerized tomography image of the structure. The mandibular OSP was measured against the midfacial OSP for its alignment. The deviation angle formed by the 2 OSPs was broken down into a y-axis component (frontal deviation angle) and a z-axis component (horizontal deviation angle). Fifty-nine patients who sought correction for facial asymmetry were included for study. RESULTS: The new analysis method was feasible. Fifty patients (83%) had significant mandibular misalignment (deviation, ≥4° or 4 mm). The locations of the rotational axes exhibited significant variations that could explain the varied features of the asymmetry. The frontal deviation angle (mean, 3.80° ± 3.89°) was significantly larger than the horizontal deviation angle (mean, 2.77° ± 1.71°). There was no significant correlation between the horizontal deviation angle and the anterior deviation distance or the posterior deviation distance. CONCLUSIONS: Proper mandibular realignment was suggested to be the primary aim in surgical correction of most jawbone asymmetries. Because of the greatly varied rotational axes and the obscure z-axis rotation, realignment could be difficult with the traditional approach. The OSP-based analysis is advocated to guide planning.