Automated artificial intelligence-based three-dimensional comparison of orthodontic treatment outcomes with and without piezocision surgery.

OBJECTIVE(S): This study aims to evaluate the influence of the piezocision surgery in the orthodontic biomechanics, as well as in the magnitude and direction of tooth movement in the mandibular arch using novel artificial intelligence (AI)-automated tools. MATERIALS AND METHODS: Nineteen patients, who had piezocision performed in the lower arch at the beginning of treatment with the goal of accelerating tooth movement, were compared to 19 patients who did not receive piezocision. Cone beam computed tomography (CBCT) and intraoral scans (IOS) were acquired before and after orthodontic treatment. AI-automated dental tools were used to segment and locate landmarks in dental crowns from IOS and root canals from CBCT scans to quantify 3D tooth movement. Differences in mesial-distal, buccolingual, intrusion and extrusion linear movements, as well as tooth long axis angulation and rotation were compared. RESULTS: The treatment time for the control and experimental groups were 13.2 ± 5.06 and 13 ± 5.52 months respectively (P = .176). Overall, anterior and posterior tooth movement presented similar 3D linear and angular changes in the groups. The piezocision group demonstrated greater (P = .01) mesial long axis angulation of lower right first premolar (4.4 ± 6°) compared with control group (0.02 ± 4.9°), while the mesial rotation was significantly smaller (P = .008) in the experimental group (0.5 ± 7.8°) than in the control (8.5 ± 9.8°) considering the same tooth. CONCLUSION: The open source-automated dental tools facilitated the clinicians' assessment of piezocision treatment outcomes. The piezocision surgery prior to the orthodontic treatment did not decrease the treatment time and did not influence in the orthodontic biomechanics, leading to similar tooth movements compared to conventional treatment.

Prevalence of mandibular asymmetry in different skeletal sagittal patterns.

OBJECTIVES: To analyze the prevalence of mandibular asymmetry in skeletal sagittal malocclusions. MATERIALS AND METHODS: PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO and gray literature (OpenGrey, ProQuest, and Google Scholar) were electronically searched. Two independent investigators selected the eligible studies, and assessed risk of bias and certainty of evidence (GRADE). One reviewer independently extracted the data and the second reviewer checked this information. Any disagreement between the reviewers in each phase was resolved by discussion between them and/or involved a third reviewer for final decision. RESULTS: Electronic search identified 5,132 studies, and 5 observational studies were included. Risk of bias was low in two studies, moderate in one, and high in two. The studies showed high heterogeneity. Mandibular asymmetry ranged from 17.43% to 72.95% in overall samples. Horizontal chin deviation showed a prevalence of 17.66% to 55.6% asymmetry in Class I malocclusions, and 68.98% in vertical asymmetry index. In Class II patients, prevalence of mandibular asymmetry varied from 10% to 25.5% in horizontal chin deviation, and 71.7% in vertical asymmetry index. The Class III sample showed a prevalence of mandibular asymmetry ranging from 22.93% to 78% in horizontal chin deviation and 80.4% in vertical asymmetry index. Patients seeking orthodontic or orthognathic surgery treatment showed greater prevalence of mandibular asymmetry. CONCLUSIONS: Skeletal Class III malocclusion showed the greatest prevalence of mandibular asymmetry. Mandibular vertical asymmetry showed a marked prevalence in all malocclusions. However, conclusions should be interpreted with caution due to use of convenience samples and low-quality study outcomes.

Three-dimensional dental and craniofacial manifestations in patients with late diagnosis of mucopolysaccharidosis type II: report of 2 cases.

The objective of this study was to report the clinical evaluation results and 3-dimensional (3-D) dental and craniofacial characteristics observed in 2 male patients with mucopolysaccharidosis type II. The patients were evaluated clinically (soft tissue evaluation, evaluation of occlusion, periodontal and dental examinations) and by using craniofacial computed tomography, with evaluation of 3-D images in ITK-Snap v. 2.2 (Penn Image Computing and Science Laboratory, Philadelphia, PA; http://www.itksnap.org/) and 3-D Slicer (http://www.slicer.org/) software. Mandibular 3-D volumetric label maps were built from computed tomography scans of both patients and compared through superimposition on a healthy patient's mandibular images. Clinically, the patients presented the following oral manifestations: macroglossia, total open bite and generalized diastemas, and absence of caries. Patient 1 showed dental calculus and bleeding at the gingival margin. Patient 2 showed bleeding at the gingival margin, a permanent maxillary left central incisor missing as a result of trauma, and impacted permanent mandibular left and right second molars. 3-D images showed wide arches, prominent antegonial notches, a narrow mandibular body in the region of the antegonial notches, bilateral severe condylar hypoplasia, and enlarged coronoid processes. 3-D imaging and superimpositions revealed oral and skeletal displacements, contributing to the identification of changes in the course of mucopolysaccharidosis type II in patients with a late diagnosis.

Long-term dental and skeletal changes in patients submitted to surgically assisted rapid maxillary expansion: a meta-analysis.

OBJECTIVE: This meta-analysis evaluated long-term dental and skeletal changes in patients submitted to surgically assisted rapid maxillary expansion. METHODS: A search was performed in electronic databases. Human clinical trials with patients submitted to surgically assisted rapid maxillary expansion with a follow-up of at least 1 year after expansion were selected. A methodological quality scoring process was used. A meta-analysis was performed to compare measurements of skeletal and dental structures. RESULTS: Three hundred sixty-five titles and abstracts were read. Ultimately 10 studies met the inclusion criteria. The 3 articles ranked as presenting low methodological quality were excluded. Three measurements could be compared and 3 time periods were used to assess changes. CONCLUSIONS: There is moderate evidence to conclude that maxillary alveolar width and intercanine and intermolar width have a long-term significant increase as a result of surgically assisted rapid maxillary expansion. A significant relapse is expected in the intercanine width after expansion.

Multidisciplinary approach to a traumatized unerupted dilacerated maxillary central incisor.

A patient with an impacted dilacerated maxillary left central incisor is presented. The 8-year-old girl also presented with protrusion of teeth and lips, posterior crossbite, anterior open bite, thumb-sucking habit, and transposition of the maxillary left lateral incisor and canine. The treatment consisted of a multidisciplinary approach, including surgery, orthodontics, endodontics, and prosthodontics. The dilacerated incisor was surgically exposed, tractioned, endodontically treated, and restored. Four premolars were extracted to correct the protrusion. The outcome was the accomplishment of a balanced and functional occlusion, resulting in a pleasant smile.

Cytotoxicity of intermaxillary orthodontic elastics of different colors: an in vitro study.

OBJECTIVES: Natural latex does not fall into the category of materials known to be entirely inoffensive. The purpose of this in vitro study was to test the hypothesis that there is no difference in the cytotoxicity between elastics of different colors and those from different manufacturers. MATERIAL AND METHODS: Different latex intraoral elastics of different colors (5/16 = 7.9 mm, mean load) were compared. The sample was divided into 7 groups of 24 elastics each: Group T (TP Orthodontics, natural latex elastics, control); Groups U1, U2, U3, U4, U5 and U6 (Uniden, natural latex elastics and colored elastics, namely, green, pink, yellow, red and purple, respectively). Cytotoxicity assays were performed by using cell culture medium containing epithelioid-type cells (Hep-2 line) derived from human laryngeal carcinoma. The cytotoxicity was evaluated by using the 'dye-uptake' test, which was employed at two different moments (0 and 24 h). Data were compared by analysis of variance (ANOVA) and Tukey's test (p<0.05). RESULTS: There was statistically significant difference (p<0.05) between Group T and all other groups (U1, U2, U3, U4, U5 and U6) at 0 and 24 h. No statistically significant difference (p<0.05) was found between Groups U1 and U5, U1 and U6, U2 and U3, U2 and U4, U2 and U5, U2 and U6, U3 and U4, U3 and U5, U3 and U6, U4 and U5, U4 and U6, and U5 and U6 at 0 and 24 h. CONCLUSIONS: The TP Orthodontics elastics promoted less cell lysis compared to the Uniden elastics regardless of their color.