Objective: The aim of our study was to qualitatively and quantitatively synthesize the evidence regarding ways to improve motivation of oral hygiene among orthodontic patients with fixed appliances and identify the effects of motivational methods via comparing the oral hygiene condition before and after the motivations. Methods: An electronic search was conducted in PubMed, Ovid, Embase, and the Crochrane Library for relevant random controlled trials (RCT) and clinical controlled trial (CCT) published before May 1^st, 2017 with manual search in addition. Search and selection of studies, quality assessment, data extraction and synthesis was completed by 2 reviewers independently. Plaque index (PI) and gingival index (GI) at 1, 3, 6-month were pooled with Review Manager 5.3. Bias of included studies was evaluated. Results: In total, 12 studies fulfilled the inclusion criteria of this systematic review, of which, 5 were included in the meta-analysis. Motivational methods had statistically significant advantage regarding PI in the experimental group over control group at 1, 3, 6-month, while GI was significantly better controlled in the study group at 3, 6-month. The quality of included studies was moderate. Conclusion: It is worthy for orthodontists to put in additional efforts to motivate patients to maintain good oral hygiene throughout the entire treatment process.

This Cross-sectional study used cone-beam computed tomography (CBCT) to evaluate the difference in the alveolar bone of the anterior teeth between high-angle adults with severe skeletal Class II malocclusions and Class III malocclusions. The CBCT archives from 62 high-angle adults were selected from patients of the Stomatology Hospital of Peking University between October 2017 to January 2018. The 62 high-angle adult subjects were divided into the following 2 groups based on their sagittal jaw relationships: severe skeletal Class II and severe skeletal Class III. Vertical bone level (VBL), alveolar bone area (ABA), and thickness of alveolar bone were measured at 2 mm, 4 mm, and 6 mm below and above to the cemento-enamel junction (CEJ) level, as well as at the apical level. Then, independent samples t-test were conducted for statistical comparisons. In the maxillary incisors, the labial VBL was smaller in the patients in skeletal Class III group than those in skeletal Class II group (P<0.05). On the labial side, the ABA was significantly thinner in patients in skeletal Class II group than those in skeletal Class III group, especially in terms of the maxillary central incisors’ ABA at 4 mm and 6 mm above the CEJ level (P<0.05), in terms of apical ABA and total ABA of the maxillary lateral incisors (P<0.05). The alveolar bone thickness around maxillary lateral incisors was significantly thinner in patients of skeletal Class II than that of patients of skeletal Class III, especially regarding the apical level on the labial side (P<0.05). The ABA of the mandibular alveolar bone in the area of the lower anterior teeth was significantly thinner in patients in skeletal Class III group than those in skeletal Class II group, especially in terms of apical ABA, total ABA on the labial and lingual sides, and ABA at 6 mm below the CEJ level on the lingual side (P<0.05). In the mandibular lateral incisors, the alveolar bone thickness was significantly thinner in patients in skeletal Class III group than it was in patients in skeletal Class II group, especially regarding the apical level on the lingual side (P<0.05). The ABA and the alveolar bone thickness of the mandibular anterior teeth were significantly thinner in the severe high-angle group of skeletal Class III adult patients than in the sample of severe high-angle skeletal Class II adult cases. Our study firstly revealed that the roots of the maxillary central and lateral incisors were placed more labially in the subjects of severe high-angle skeletal Class II than in those of severe high-angle skeletal Class III, especially in the lateral incisors.

Objective: : To evaluate if the improved accelerated osteogenic orthodontics (IAOO) procedure could speed Class III surgical patients' preoperative orthodontic treatment duration and, if yes, to what extent. This study was also designed to determine whether or not an IAOO procedure affects the tooth-moving pattern during extraction space closure. Materials and Methods: : The samples in this study consisted of 24 Class III surgical patients. Twelve skeletal Class III surgery patients served as an experimental group (group 1) and the others as a control group (group 2). Before treatment, the maxillary first premolars were removed. For group 1, after the maxillary dental arch was aligned and leveled (T2), IAOO procedures were performed in the maxillary alveolar bone. Except for this IAOO procedure in group 1, all 24 patients experienced similar combined orthodontic and orthognathic treatment. Study casts of the maxillary dentitions were made before orthodontic treatment (T1) and after extraction space closure (T3). All of the casts were laser scanned, and the amount of movement of the maxillary central incisor, canine, and first molar, as well as arch widths, were digitally measured and analyzed by using the three-dimensional model superimposition method. Results: : The time durations T3–T2 were significantly reduced in group 1 by 8.65 ± 2.67 months and for T3–T1 were reduced by 6.39 ± 2.00 months ( P < .001). Meanwhile, the tooth movement rates were all higher in group 1 ( P < .05). There were no significant differences in the amount of teeth movement in the sagittal, vertical, and transverse dimensions between the two groups ( P > .05). Conclusion: : The IAOO can reduce the surgical orthodontic treatment time for the skeletal Class III surgical patient by more than half a year on average. The IAOO procedures do not save anchorage.

The present systematic review and meta-analysis aimed to test the hypothesis that no facial soft tissue changes occur after nonsurgical rapid maxillary expansion (RME), in order to provide a reference for orthodontists. PubMed, EMBASE, Cochrane Library, OVID, MEDLINE, CINAHL, Scopus, and ScienceDirect databases were electronically and manually searched up to December 2017, and randomized controlled, clinical controlled trials, cohort studies and retrospective studies where soft tissue changes were measured before and after nonsurgical RME were identified. Study appraisal and synthesis were performed by two reviewers who completed the study selection and quality assessment procedures independently and in duplicate. Data from the involved studies were pooled using Revman 5.3. A total of 1762 articles were identified after the removal of duplicates. After selection and quality assessment, 15 studies met the inclusion criteria for the systematic review, and 13 articles were ultimately included in the meta-analysis. The quality of the involved studies was relatively moderate. Pre-expansion, postexpansion, and postretention data were pooled. The nasal width, alar base width, and distances from the lower lips to the E line showed significant changes after expansion. Moreover, after retention, the nasal width, mouth width, upper philtrum width, and distance from the lower lip to the E line showed significant increases relative to the baseline values. Limitations of the present study included the moderate quality of the included studies and the fact that the results were based on short-term observations of patients in the growth phase. Our findings suggest that RME results in a significantly increased nasal width, mouth width, upper philtrum width, and distance from the lower lip to the E line after the retention phase. However, the clinical importance of these findings is questionable.

Background: Low-intensity pulsed ultrasound (LIPUS) can accelerate tooth movement and preserve tooth and bone integrity during orthodontic treatment. However, the mechanisms by which LIPUS affects tissue remodeling during orthodontic tooth movement (OTM) remain unclear. Periodontal ligament cells (PDLCs) are pivotal in maintaining periodontal tissue equilibrium when subjected to mechanical stimuli. One notable mechano-sensitive ion channel, Piezo1, can modulate cellular function in response to mechanical cues. This study aimed to elucidate the involvement of Piezo1 in the osteogenic response of force-treated PDLCs when stimulated by LIPUS.Method: After establishing rat OTM models, LIPUS was used to stimulate rats locally. OTM distance and alveolar bone density were assessed using micro-computed tomography, and histological analyses included hematoxylin and eosin staining, tartrate-resistant acid phosphatase staining and immunohistochemical staining. GsMTx4 and Yoda1 were respectively utilized for Piezo1 functional inhibition and activation experiments in rats. We isolated human PDLCs (hPDLCs) in vitro and evaluated the effects of LIPUS on the osteogenic differentiation of force-treated hPDLCs using real-time quantitative PCR, Western blot, alkaline phosphatase and alizarin red staining. Small interfering RNA and Yoda1 were employed to validate the role of Piezo1 in this process.Results: LIPUS promoted osteoclast differentiation and accelerated OTM in rats. Furthermore, LIPUS alleviated alveolar bone resorption under pressure and enhanced osteogenesis of force-treated PDLCs both in vivo and in vitro by downregulating Piezo1 expression. Subsequent administration of GsMTx4 in rats and siPIEZO1 transfection in hPDLCs attenuated the inhibitory effect on osteogenic differentiation under pressure, whereas LIPUS efficacy was partially mitigated. Yoda1 treatment inhibited osteogenic differentiation of hPDLCs, resulting in reduced expression of Collagen Ⅰα1 and osteocalcin in the periodontal ligament. However, LIPUS administration was able to counteract these effects.Conclusion: This research unveils that LIPUS promotes the osteogenesis of force-treated PDLCs via downregulating Piezo1.