Measurement plane of the cross-sectional area of the masseter muscle in patients with skeletal Class III malocclusion: An artificial intelligence model.

Introduction: This study aimed to determine a measurement plane that could represent the maximum cross-sectional area (MCSA) of masseter muscle using an artificial intelligence model for patients with skeletal Class III malocclusion.

Methods: The study included 197 patients, divided into subgroups according to sex, mandibular symmetry, and mandibular plane angle. The volume, MCSA, and the cross-sectional area (CSA) at different levels were calculated automatically.

China experts' consensus on preventive and interceptive orthodontic treatments of malocclusions of children.

Malocclusion is one of the three most common oral diseases reported by World Health Organization(WHO). In China, its incidence rate is rising. Malocclusion seriously affects the dental and maxillofacial function, facial appearance and growth development of nearly 260 million children in China, and what is more, it affects their physical and mental health development.

Analysis of correlation of 3-dimensional lip vermilion morphology and dentoskeletal forms in young Chinese adults on the basis of sex and skeletal patterns.

Introduction: The objective of this research was to evaluate the correlation between 3-dimensional (3D) lip vermilion (LV) morphology and skeletal patterns as well as incisor measurements in young Chinese adults.

Methods: In all, 240 young adults were enrolled; these included 80 patients each with skeletal Class I, Class II, and Class III malocclusions, respectively. Each sagittal skeletal pattern included 40 male and 40 female subjects.

Three-dimensional analysis of the physiologic drift of adjacent teeth following maxillary first premolar extractions.

We assessed the three-dimensional (3D) pattern of the physiologic drift of the remaining adjacent teeth after premolar extraction due to orthodontic reasons and the associated factors. Data were collected from 45 patients aged 17.04 ± 5.

Three-dimensional changes in lip vermilion morphology of adult female patients after extraction and non-extraction orthodontic treatment.

Objective: To investigate the three-dimensional lip vermilion changes after extraction and non-extraction orthodontic treatment in female adult patients and explore the correlation between lip vermilion changes and incisor changes.

Methods: Forty-seven young female adult patients were enrolled in this study (skeletal Class III patients were excluded), including 34 lip-protruding patients treated by extraction of four first premolars (18 patients requiring mini-implants for maximum anchorage control and 16 patients without mini-implants) and 13 patients requiring non-extraction treatment. Nine angles, seven distances, and the surface area of the lip vermilion were measured by using pre- and post-treatment three-dimensional facial scans.

Posteroanterior cephalometric analysis of White-American and Chinese adolescents: a cross-sectional study.

: To characterize ethnic differences between Chinese and White-Americans between 8.5 and 17.5 years of age, with respect to transverse cephalometric characteristics and to establish transverse craniofacial normative values for Chinese adolescents.

Correlation Between Cephalometric Measures and End-of-Treatment Facial Attractiveness.

Sixty-nine experienced Chinese orthodontists evaluated 108 Chinese patients' facial attractiveness from set of photographs (frontal, lateral, and frontal smiling photos) taken at the end of orthodontic treatment. These 108 patients, which contained an equal number of patients with Class I, II, and III malocclusion, were randomly selected from 6 orthodontic treatment centers throughout China. Spearman rank-order correlation coefficients (rs) analyses were performed to examine agreement in ranking between all judge pairs.

[Validation of subjective and objective evaluation methods for orthodontic treatment outcome].

Objective: To assess the correlations between objective measurements of 108 finished orthodontic cases and subjective assessments made by 69 orthodontic specialists, to explore the statistically significant measuring categories of cast and cephalogram and to validate the regression model.

Methods: A stratified random sample of 108 cases was drawn from the large sample of 2 383 patients who finished orthodontic treatment between July 2006 and August 2008 in six orthodontic treatment centers around China. For each patient, the post-treatment information sources evaluated in this study included standardized plaster study casts and a lateral cephalometric X-ray image.

Root resorption before and after orthodontic treatment: a clinical study of contributory factors.

This clinical study evaluated factors related to root resorption before (T1) and after (T2) orthodontic treatment. Ninety-six subjects between 9 and 34 years (34 males and 62 females) who had been treated using fixed appliances for at least 1 year and who had panoramic radiographs at T1 and T2 were selected. The relationship between root resorption at T1 and T2, with regard to gender, age, extraction versus non-extraction patterns, specific teeth and treatment duration was investigated.

[Non-extraction treatment with self-ligating and conventional brackets].

Objective: To compare the dental change and the mechanism after non-extraction treatment between passive self-ligating and conventional bracket systems.

Methods: Twenty-six non-extraction crowding cases were selected. Half of them were treated with Damon3 self-ligating brackets and the others were treated with conventional brackets.

Reconstruction of a huge oral maxillofacial defect caused by necrotic fasciitis secondary to leukaemia.

An 8-year-old boy who was diagnosed with 'acute non-lymphoblastic leukaemia (M2)', contracted secondary oral maxillofacial necrotic fasciitis. The wound was cleaned with 3% hypertonic saline, and then covered with iodoform gauze every day for about 3 weeks before and after necrotic tissue debridement. The local infection was controlled, and plenty of new healthy granular tissue had grown.

[Gnathosonics study of the occlusal stability of orthodontic patients].

Objective: To analysis the stability of the occlusion before and after the orthodontic treatment by gnathosonics; To evaluate the reliability of the stethoscope method by comparing the subjective(stethoscopy) and objective(digital occlusal sound recording) methods of checking the occlusal sound.

Methods: Sixty-four new patients with malocclusion were selected as the before treatment group, these patients were not subject to any previous orthodontic treatment, facial surgery or injury; the treatment complete group included 15 patients who were just debonded the fixed appliance. Both stethoscope and digital occlusal sound recording were used to evaluate the occlusal sound.

[A factors study of root resorption after orthodontic treatment].

Objective: To investigate the factors relating to root resorption after orthodontic treatment.

Methods: 96 cases treated with fixed appliances were selected. The panoramic radiographs before and after treatment were examined.