Systematic Analysis of Clinical Outcomes of Bilateral Sagittal Split Ramus Osteotomy With Preoperative Modeling and Postoperative Orthodontic in the Treatment of Mandibular Protrusion.

The purpose of this study was to determine the changes in hard tissues, soft tissues, and teeth after bilateral sagittal split ramus osteotomy and orthodontic treatment for the treatment of mandibular protrusion. Cephalometric analysis was used to evaluate the aesthetic effects and occlusal relationships obtained. The subjects included 11 women and 9 men (aged 18-27 years; average, 20 years) with mandibular protrusion who underwent bilateral sagittal split ramus osteotomy. Based on a preoperative computer-aided manufacturing/design-assisted, model surgical design and an occlusal guide plate, new occlusal relationships were established for the patients. In addition, the preoperative and the end of postoperative orthodontic treatment cephalometric radiographs were systematically analyzed. In all patients, the surgical incisions underwent primary healing, with no infection or osteonecrosis. Significant differences were observed in the preoperative and the end of postoperative orthodontic treatment values of all hard tissue and teeth parameters, except for SNA°, ANB°, GoGn-SN°, SE (mm), NP-FH°, SGn-FH°, OP-FH°, 1-MP°, Li-E (mm). The most obvious significant differences were seen in SNB°, SND°, 1_-NA°, 1_-NA (mm), 1-NB (mm), 1-NB°, Po-NB (mm), NA-PA°, AB-NP°, 1-OP°, Ui-E (mm), and S-N'-B'° (P < 0.001). Postoperative follow-up lasted for 10 to 12 months. All patients eventually achieved normal downjaw relationship, tooth arch forms, and spee curves. There were no evident irregularities of teeth arrangement or abnormal occlusal relationships were observed. All patients were satisfied with their facial appearance and occlusal relationships at the end of postoperative orthodontic treatment. The authors found a precise preoperative model surgical design combined with postoperative orthodontic treatment is a simple and time-saving technique. It can be used to correct mandibular protrusion with satisfactory occlusal relationship, facial appearance, and minimal postoperative complications.

Non-invasive assessment of periodontal inflammation by continuum-removal hemodynamic spectral indices.

BACKGROUND: Hyperspectral techniques have aroused great interest in non-invasively measuring periodontal tissue hemodynamics. However, current studies mainly focused on three typical inflammation stages (healthy, gingivitis and periodontitis) and practical approaches for using optical spectroscopy for early and precisely detection of periodontal inflammation at finer disease stages have not been well studied. METHODS: This study provided novel spectroscopic insights into periodontitis at different stages of disease, and developed six simple but physically meaning hemodynamic spectral indices (HSIs) including four spectral absorption depths of oxyhemoglobin ( D HbO 2 ), deoxyhemoglobin ( D Hb ), total hemoglobin ( t Hb ) and tissue water ( D water ), and two normalized difference indices of oxyhemoglobin( N D HbO 2 I ) and deoxyhemoglobin ( N D Hb I ) from continuum-removal spectra (400-1700 nm) of periodontal tissue collected from 47 systemically healthy subjects over different severities from healthy, gingivitis, slight, moderate to severe periodontitis for early and precision diagnostics of periodontitis. Typical statistical analyses were conducted to explore the effectiveness of the proposed HSIs. RESULTS: D Hb and t Hb exerted significant increasing trends as inflammation progressed, whereas D HbO 2 exhibited significant difference (P < 0.05) from the healthy sites only at moderate and severe periodontitis and D water presented unstable sensitives to disease severity. By contrast, N D HbO 2 I and N D Hb I showed more steadily downward trends as severity increased, and demonstrated the highest correlations with clinical gold standard parameters. Particularly, the proposed normalized HSIs ( N D HbO 2 I and N D Hb I ) yielded high correlations of - 0.49 and - 0.44 with probing depth, respectively, far outperforming results achieved by previous studies. The performances of the HSIs were also confirmed using the periodontal therapy group. CONCLUSIONS: These results indicated great potentials of combination optical spectroscopy and smart devices to non-invasively probe periodontitis at earlier stages using the simple and practical HSIs. Trial registration This study was retrospectively registered in the Chinese Clinical Trial Registry on October 24, 2021, and the clinical registration number is ChiCTR2100052306.

Integrating genomics, molecular docking, and protein expression to explore new perspectives on polystyrene biodegradation.

Faced with the escalating challenge of global plastic pollution, this study specifically addresses the research gap in the biodegradation of polystyrene (PS). A PS-degrading bacterial strain was isolated from the gut of Tenebrio molitor, and genomics, molecular docking, and proteomics were employed to thoroughly investigate the biodegradation mechanisms of Pseudomonas putida H-01 against PS. Using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (ATR-FTIR), and contact angle analysis, significant morphological and structural changes in the PS films under the influence of the H-01 strain were observed. The study revealed several potential degradation genes and ten enzymes that were specifically upregulated in the PS degradation environment. Additionally, a novel protein with laccase-like activity, LacQ1, was purified from this strain for the first time, and its crucial role in the PS degradation process was confirmed. Through molecular docking and molecular dynamics (MD) simulations, the interactions between the enzymes and PS were detailed, elucidating the binding and catalytic mechanisms of the degradative enzymes with the substrate. These findings have deepened our understanding of PS degradation.

Systematic analysis of clinical outcomes of anterior maxillary and mandibular subapical osteotomy with preoperative modeling in the treatment of bimaxillary protrusion.

The purpose of this study was to determine the changes in teeth and hard tissues after preoperative modeling and bimaxillary anterior subapical osteotomy for the treatment of bimaxillary protrusion. Cephalometric analysis was used to evaluate the aesthetic effects and occlusal relationships obtained. The subjects included 19 women and 1 man (aged 19-41 years; average, 29 years) with bimaxillary protrusion who underwent anterior subapical osteotomy of both the maxilla and mandible, with simultaneous genioplasty, if required. Based on a preoperative computer-aided manufacturing/design-assisted and model surgical design and an occlusal guide plate, new occlusal relationships were established for the patients. In addition, the preoperative and postoperative cephalometric radiographs were systematically analyzed. In all patients, the surgical incisions underwent primary healing, with no infection or osteonecrosis. Significant differences were observed in the preoperative and postoperative values of all hard tissue and teeth parameters, except for SGn-FH degrees and Co-MP. The most obvious significant differences were seen in L1-OP°, Id-Pog-Go°, IIA°, U1E-Apog, L1E-Apog, U1E-NA, and L1-NA° (P < 0.001). Postoperative follow-up lasted for 12 to 36 months. All patients eventually achieved normal jaw relationships, tooth arch forms, and Spee curves. No evident irregularities of teeth arrangement or abnormal occlusal relationships were observed. All patients were satisfied with their postoperative facial appearance, except for 1 patient, who underwent repeat surgery because of relapse. With the use of a precise preoperative model surgical design, orthognathic surgery, a simple and time-saving technique, can be used to correct bimaxillary protrusion with satisfactory postoperative occlusal relationship and facial aesthetic appearance and minimal postoperative complications.

Ectopic osteogenesis of allogeneic bone mesenchymal stem cells loading on ß-tricalcium phosphate in canines.

BACKGROUND: Bone mesenchymal stem cells are progenitor cells for mesenchymal tissues. The objective of this study was to evaluate the subcutaneous ectopic osteogenesis of allogeneic bone mesenchymal stem cells, which were loaded on ß-tricalcium phosphate in canines without immunosuppressive therapy. METHODS: Osteoinduced allogeneic bone mesenchymal stem cells were seeded onto a ß-tricalcium phosphate scaffold to construct tissue-engineered bone. Four dogs (recipients) in the allogeneic group were subcutaneously implanted with the allogeneic bone mesenchymal stem cells/scaffold; four dogs (donors) in the autogeneic group were implanted with the autogeneic bone mesenchymal stem cells/scaffold complex; and four dogs in the control group were implanted with scaffold alone. Systemic immune responses were evaluated by measuring the T-lymphocyte CD4, CD8, and CD4/CD8 subsets of each group. Subcutaneous osteogenesis was compared between the three groups by histologic analysis at week 24 after implantation. RESULTS: Flow cytometry showed no significant differences in the number of CD4 and CD8 T cells and the CD4/CD8 T-cell ratios among the three groups. Histologically, at week 24, both the autogeneic and allogeneic complexes led to subcutaneous osteogenesis, whereas the control group alone did not. There were no significant differences in the percentage of osteogenic area between the allogeneic and the autogeneic complexes on histomorphometric analysis (p > 0.05), which was significantly higher than that produced by the control group alone (p < 0.001). CONCLUSION: The results demonstrate that osteoinduced, allogeneic bone mesenchymal stem cells loaded on ß-tricalcium phosphate enhanced ectopic bone formation in canines without immunosuppressive therapy.