Nomogram prediction of vulnerable periodontal condition before orthodontic treatment in the anterior teeth of Chinese patients with skeletal Class III malocclusion.

OBJECTIVE: To establish and verify models predictive of thin periodontal phenotype and alveolar fenestration/dehiscence in the anterior teeth of patients with skeletal Class III malocclusion. MATERIAL AND METHODS: Retrospective data of 669 anterior teeth (305 in maxillae and 364 in mandibles) from 80 patients with skeletal Class III malocclusion before augmented corticotomy were collected. Distribution of thin periodontal phenotype and alveolar fenestration and dehiscence were evaluated and their associations with potential influencing factors were explored using univariate and multivariate analyses. The predictive models were visualized as nomograms, the accuracy of which was tested by receiver operating curve analyses. RESULTS: Thin phenotype was associated with Mazza bleeding index, sex, tooth type, probing depth and width of keratinized gingiva (WKG). Labial dehiscence was associated with age, jaw, labial bone thickness, mandibular plane angle, sagittal root position (SRP), sex, tooth type, and WKG. Labial fenestration was associated with sex, tooth type, SRP, and periodontal phenotype. The areas under the curves of nomogram prediction models for periodontal phenotype, alveolar dehiscence, and alveolar fenestration were 0.84, 0.81, and 0.73, respectively. CONCLUSIONS: Female sex, lateral incisor, and limited WKG may be risk factors for thin periodontal phenotype. Age, canine, male sex, mandible, thin labial bone thickness, and root positioned against the labial plate may be risk factors for labial dehiscence; and female sex, thick phenotype, root positioned against the labial plate, lateral incisor, and canine may be risk factors for labial fenestration. The predictive performance of the models was acceptable.

Prevalence of and risk factors for alveolar fenestration and dehiscence in the anterior teeth of Chinese patients with skeletal Class III malocclusion.

INTRODUCTION: This study investigated the prevalence of and risk factors for alveolar fenestration and dehiscence in the anterior teeth of Chinese patients with skeletal Class III malocclusion. METHODS: This study included clinical and radiographic examinations and intraoperative observations of 460 anterior teeth from 54 patients who underwent corticotomy and periodontal regenerative surgery before orthodontic treatment. Fenestration and dehiscence were detected and recorded during open-flap surgery. Univariate and multivariate analyses were performed to assess relationships between fenestration and dehiscence and age, sex, history of previous orthodontic treatment, mandibular plane angle, dentition, tooth position, sagittal root position, periodontal biotype, gingival recession, width of keratinized gingiva, and width of the basal bone. RESULTS: The prevalence of buccal alveolar bone defects was 16.1% (fenestration) and 20.7% (dehiscence) at the tooth level. Multivariate logistic regressions showed that fenestration was significantly associated with tooth position (canine vs central incisor, odds ratio [OR] = 3.324; P = 0.006; lateral incisor vs central incisor, OR = 5.588; P  <0.001), and sagittal root position (buccally positioned vs centrally positioned, OR = 5.865; P = 0.025). Dehiscence was significantly associated with dentition (mandible vs maxilla, OR = 11.685; P  <0.001), tooth position (canine vs central incisor, OR = 3.863; P = 0.007), age (OR = 1.227; P = 0.010), sex (male vs female, OR = 5.530; P = 0.026), and history of orthodontic treatment (yes vs no, OR = 4.773; P = 0.028). CONCLUSIONS: Buccally positioned teeth in the osseous housing, lateral incisors, and canines were more likely to exhibit alveolar fenestration. Mandibular teeth and canines, patients who were older, were male, and had a history of orthodontic treatment, were more likely to exhibit alveolar dehiscence.

Periodontal Effect of Periodontally Accelerated Osteogenic Orthodontics in Skeletal Angle Class III: A Nonrandomized, Controlled Trial.

The objective of this study was to evaluate the effect of periodontally accelerated osteogenic orthodontics (PAOO) on gingivae and alveolar bone by analysis of clinical and cone beam computed tomography (CBCT) parameters in the treatment of 20 skeletal Class III patients. The patients included in this study were divided into test and control groups. Periodontal parameters such as probing depth (PD), gingival recession (GR), keratinized gingival width, and alveolar bone thickness of CBCT scans were measured and recorded preoperation (T0) and at 6 months postoperative (T1). The difference in PD from T0 to T1 between the two groups was not statistically significant (0.01 ± 0.46 mm vs 0.22 ± 0.65 mm, respectively; P > .05). No significant difference in GR was observed from T0 to T1 between the two groups (0.03 ± 0.26 mm vs -0.03 ± 0.27 mm, respectively; P > .05). Alveolar bone thickness (4 mm apical to the cementoenamel junction [CEJ]) change from T0 to T1 was -0.31 ± 0.35 mm for the control group and 0.06 ± 0.69 mm for the test group (P < .05). Meanwhile, alveolar bone thickness (6 mm apical to CEJ) changes from T0 to T1 were -0.38 ± 0.54 mm and 0.10 ± 0.80 mm for the control and test groups, respectively (P < .05). It was determined that PAOO in the treatment of skeletal Class III patients is effective and safe to periodontium on the basis of clinical and CBCT parameters.

Periodontal soft- and hard-tissue changes after augmented corticotomy in Chinese adult patients with skeletal Angle Class III malocclusion: A non-randomized controlled trial.

BACKGROUND: To investigate soft- and hard-tissue changes after augmented corticotomy in Chinese adult patients with skeletal Angle Class III malocclusion. METHODS: This non-randomized controlled trial included 357 anterior teeth from 30 Chinese adult patients with skeletal Angle Class III malocclusion for whom the proposed treatment was augmented corticotomy. Jaws receiving surgery were allocated to a test group (S, surgical group, n = 47) and jaws not receiving surgery were allocated to a control group (NS, non-surgical group, n = 13). Changes in the periodontal biotype, width of the keratinized gingiva (WKG), and labial and lingual horizontal bone thicknesses (BTs) were compared 6 months after surgery by univariate and multivariate analyses. RESULTS: After adjustment for confounding variables, average gains of 0.473 mm in the WKG and 0.649 mm in the labial BT were found in the S group relative to the NS group (P <0.05). The odds of transition from a thin periodontal biotype to a thick biotype in the S group were about 230 times those in the NS group, and the odds of the reverse biotype transition in the NS group were about 83 times those in the S group (P <0.05). CONCLUSIONS: Within the limitations of the present study, augmented corticotomy is a promising approach to improve insufficient periodontal soft and hard tissues in Chinese adult patients with skeletal Angle Class III malocclusion.

Association between Periodontal Biotype and Clinical Parameters: A Cross-sectional Study in Patients with Skeletal Class III Malocclusion.

OBJECTIVE: To evaluate the prevalence of periodontal biotypes in patients with skeletal Class III malocclusion and to explore its association with age, gender, other periodontal clinical parameters and width of keratinized gingiva (WKG). METHODS: Data were collected for the buccal-middle site of 310 anterior teeth from 26 subjects who received periodontally accelerated osteogenic orthodontics (PAOO) surgery before orthodontic treatment. Univariate and multivariate analysis were performed to calculate and test the correlations between periodontal biotype and age, gender and bleeding index (BI), gingival recession (GR), plaque index (PLI), probing depth (PD) and WKG. RESULTS: Prevalence of thin periodontal biotype was 33.9% in the anterior region. Mean WKG was 4.37 mm. Univariate analysis showed that a moderately positive correlation was found between WKG and thick biotype (r = 0.544, P < 0.001). A low positive correlation was detected between mandibular teeth and thick biotype (r = 0.387, P < 0.001) and a low negative correlation was detected between GR and thick biotype (r = -0.308, P < 0.001). Multi-level logistic regression showed that biotype was significantly associated with dental arch (odds ratio [OR] = 0.174, P = 0.015) and WKG (OR = 2.043, P = 0.002). No significant associations were detected between biotype and other factors. CONCLUSION: Dental arch and WKG were associated with periodontal biotype in patients with skeletal Class III malocclusion.