Analysis of condylar positioning in the temporomandibular joint following mandibular reconstruction: Introduction of a new classification system and assessment of influencing factors on displacement.

OBJECTIVE: This study investigates the unsatisfactory outcomes observed in mandibular reconstruction procedures attributed to improper condylar positioning in the Temporomandibular Joint. It also proposes a systematic classification for post-reconstruction condylar positioning dissatisfaction. METHODS: A retrospective analysis was conducted on 337 patients who underwent tumor removal and mandibular reconstruction with vascularized osteocutaneous flaps. Reconstruction techniques included conventional surgery (43.3%) and 3D technology-guided procedures (56.7%). Evaluation utilized preoperative and postoperative CT scans to assess mandibular vertical ramus length (V) and condylar alignment in both sagittal (S) and coronal (C) planes. Accordingly, a classification system for condylar positioning was developed and abbreviated as VSC. It includes four classes: Class I, proper condylar reconstruction; Class II, short ramus length; Class III, one or two aspects of sagittal/coronal condylar positions dissatisfaction; and Class IV, two or three aspects dissatisfaction. RESULTS: The overall success rate for condylar reconstruction was 85.16%. Though not statistically significant, the success rate was marginally higher in the 3D-assisted group (85.86%) compared to the conventional group (84.25%). In terms of the VSC classification, the distribution of cases across Class I, II, III, and IV were 287, 4, 9, and 37 cases, respectively. Notably, condylar dislocation was significantly associated with the defect site, particularly the body and condyle (p < 0.001, OR = 49.734, 95% CI 12.995-190.342), and the number of reconstructed segments (p = 0.025, OR = 3.480, 95% CI 1.173-10.328). CONCLUSION: The findings highlight the importance of accurate reconstruction methods and reveal implications of the defect site and the number of reconstructed segments in condylar dislocation. Consequently, we propose a classification system to refine condylar positioning assessment and enhance surgical outcomes in mandibular reconstruction.

Single vs. Double-Opposing Z-Plasty: Evaluating Their Impact on Palatoplasty Postoperative Outcomes.

BACKGROUND: The double-opposing Z-plasty is a fundamental approach for cleft palate repair. Recently, some surgeons have begun implementing a single Z-Plasty, igniting discussions on the most effective technique for enhancing postoperative outcomes. Consequently, this study sought to evaluate the outcomes of employing single and double Z-plasties within the modified Sommerlad-Furlow technique. METHODS: 116 cleft palate patients undergoing primary surgical repair were divided into two groups: those treated with the Sommerlad-Furlow method using a double-opposing Z-plasty (S.F.2.Z.P. group, n = 58) and those receiving a single nasal Z-plasty (S.F.1.Z.P. group, n = 58). Data on cleft type and width, soft palate length, palatal fistula, and velopharyngeal function were collected. Mann-Whitney test compared the mean values between groups. RESULTS: The S.F.2ZP group demonstrated a statistically significant increase in soft palate length compared to those in the S.F.1ZP group (p = 0.008). However, the S.F.1ZP group demonstrated adequate soft palate length (7.9 ± 2.8 mm) compared to the S.F.2ZP group (9.3 ± 2.8 mm). The velopharyngeal function was good in both groups, with no significant differences (P = 0.52). While the proper velopharyngeal closure was 81% in the S.F.1ZP group and 87.9% in the S.F.2ZP group, velopharyngeal insufficiency was 10.3% and 5.2%, respectively. The rates of persistent palatal fistula were 5.2% in the S.F.1ZP group and 3.4% in the S.F.2ZP group, with no significant differences found between both groups (P = 0.64). CONCLUSIONS: There were no significant differences in crucial outcomes such as velopharyngeal function and the incidence of persistent palatal fistulas, indicating the effectiveness of both techniques. While the double-opposing Z-plasty demonstrated a statistically significant increase in soft palate length, the a nasal Z-plasty demonstrated adequate soft palate length which sufficiently enables effective velopharyngeal closure. These outcomes suggest that a single Z-plasty is both effective and easy to perform, making it a valuable surgical approach for achieving the desired outcomes.. CLINICAL RELEVANCE: The current study suggests that although the soft palate may not be as elongated with nasal Z-plasty alone compared to the double Z-plasty, it sufficiently enables effective velopharyngeal closure.

Fibroblast regulates angiogenesis in assembled oral cancer organoid: A possible role of NNMT.

OBJECTIVE: Tumour angiogenesis is affected by various cell types in the tumour microenvironment (TME), including cancer cells and cancer-associated fibroblasts (CAFs). Here, an assembled organoid model was generated to investigate the mechanism by which the TME regulates angiogenesis in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Secretion of vascular endothelial growth factor-A (VEGFA) was analysed to compare the proangiogenic properties of OSCC cells and corresponding CAFs. Cell aggregates consisting of endothelial cells (ECs), CAFs and cancer cells were generated to construct assembled organoids. Nicotinamide N-methyltransferase (NNMT) was pharmacologically or genetically inhibited to block the activation of CAFs. ATAC-seq was employed to test the transcriptional network of fibroblasts overexpressing NNMT. RESULTS: Compared with cancer cells, CAFs secreted more VEGFA. Coculture with CAFs more effectively promoted the sprouting of ECs. Blockade of CAF activation via inhibition of NNMT drastically reduced the expression of CD31 in the assembled organoids. Overexpression of NNMT enhanced the transcription of genes related to angiogenesis in fibroblasts. Specifically, NNMT orchestrated the enrichment of the transcription factor JUNB at the promoter of VEGFA. CONCLUSIONS: We clarify that stromal NNMT enables the steady reproduction of angiogenesis in assembled oral cancer organoids, providing a novel target for exploiting antiangiogenic therapy.

Evaluation of late cleft palate repair by a modified technique without relaxing incisions.

OBJECTIVE: To evaluate the postoperative outcomes together with analyzing the associated influencing factors following a late cleft palate repair by the Sommerlad-Furlow modified technique (S-F). MATERIALS AND METHODS: In a retrospective cohort, 320 consecutive patients with cleft palate, who received S-F technique between 2011 and 2017, were reviewed. The patients were divided into three age groups, less than one year (143), one to two years (113), and greater than 2 years (64). The postoperative outcomes included wound healing (complete/fistula) and velopharyngeal function (VPF). RESULTS: The overall cleft width was 10 ± 3.07 mm. The overall rates of complete wound healing and proper velopharyngeal function were 96.6% and 81.56%, respectively. No significant difference was found between the age groups regarding wound healing, with an overall fistula rate of 3.4%. The VPF was significantly varied among the age groups (P<0.001). In context, the rates of velopharyngeal insufficiency (VPI) were 9.8%, 14.2%, and 45.4% among patients repaired at ˂1, 1-2, and >2 years old, respectively. The cleft type was the most potential factor associated with fistula. The age at repair was identified as the most implicating factor for VPI. CONCLUSIONS: The S-F technique had achieved low fistula rate and satisfactory speech outcome, especially in early repair group and even in the wide cleft palate. The older age at repair and severe cleft type had a major impact on the postoperative outcomes.

Tissue-engineered bone using mesenchymal stem cells versus conventional bone grafts in the regeneration of maxillary alveolar bone: A systematic review and meta-analysis.

PURPOSE: The aim of this study was to compare tissue-engineered bone using mesenchymal stem cells (MSCs) and conventional bone grafts in terms of histomorphometric outcome, bone gained, and implant failure in the atrophic maxilla. MATERIALS AND METHODS: A systematic review and meta-analysis of randomized clinical trials (RCTs) was conducted. An electronic search of several databases was performed. RCTs comparing tissue-engineered bone using MSCs to bone graft alone in rehabilitation of the atrophic maxilla were included. Outcome variables were a mean percentage of new bone formation, residual graft particles, and connective tissue. Bone gained and implant failure rate were also assessed. Risk ratio (RR) or standardized mean differences (SMD) were statistically analyzed. RESULTS: A total of 190 augmented sites enrolled in 12 RCTs were included in this study. Nine of the 12 RCTs included 153 maxillary sinuses that underwent sinus elevation, and three RCTs included 28 patients with bone grafting only. There was no significant increase in new bone formation between the two groups at 3 to 4 months (SMD = -0.232, CI, -0.659 to 0.195, low-quality evidence). However, at 6 months postgrafting, a statistically significant increase in new bone formation was found in favor of the tissue-engineered bone using the MSC group (SMD = 0.869%, CI, -1.98 to 9.310, moderate-quality evidence). No substantial difference was found between the two groups with respect to residual graft particles, connective tissue, bone gained, and implant failure rate (RR = 2.8, CI: 0.517 to 16.6, P = .226, very low-quality evidence). CONCLUSION: There is moderate- to very low-quality evidence supporting the use of tissue-engineered bone using MSC therapy in maxillary alveolar bone regeneration compared with conventional bone grafting without MSCs.