Using Auricular Cartilage-fascia Composite Tissue Free Grafting Technique to Improve Cartilage Survival Outcomes.

OBJECTIVES: Auricular cartilage graft has a wide range of applications in plastic and reconstructive surgery. However, there is still a risk of absorption of the grafts over time. Intrinsic postauricular fascia (IPF) with a rich vascular network may play an important role in the nutrition and repair of auricular cartilage. This study aimed to investigate the effect of IPF on the survival viability of free auricular cartilage grafts. METHODS: 24 auricular cartilages were obtained from 6 New Zealand white rabbits which were divided into the cartilage-fascia composite graft group (FC group, n=12) and the cartilage without fascia group (C group, n=12). Two groups of cartilage were implanted into each side of the subcutaneous pocket of the rabbit's dorsum. The rabbits were sacrificed after 3 months and all cartilage grafts were obtained. Macroscopic observation, histopathological staining, and biomechanical testing were performed on all specimens. RESULTS: There were significant differences between the 2 groups regarding proliferating chondrocytes, apoptotic chondrocytes, vascularization, and matrix collagen. Compared to the auricular cartilage grafts without fascia, the auricular cartilage-fascia composite grafts had more neovascularization, proliferative chondrocytes, and type II collagen, with a homogeneous cartilage matrix and no obvious areas of heterogeneous staining. Young's modulus and ultimate tensile strength of cartilage were reduced in both groups compared to pretransplantation, but the composite graft group was superior to the fascia-free group. CONCLUSIONS: Auricular cartilage-fascial composite tissue free graft could improve cartilage survival outcomes with higher viability and mechanical properties.

3D-CT measurements of facial symmetry in severe CFM patients: A comparative study between mandibular ascending ramus distraction osteogenesis and bone grafting.

This study aims to compare the effects of mandibular distraction osteogenesis (MDO) and bone grafting on the facial symmetry of children with Pruzansky-Kaban type IIB and III craniofacial microsomia (CFM). Medical records and three-dimensional computed tomography (3D-CT) data of CFM patients who had primarily undergone MDO and bone grafting were collected. A retrospective analysis of pre-and post-operative 3D imaging data was conducted to compare the improvement rate in facial symmetry between the two groups based on occlusal cant, affected/unaffected ramus height ratio and chin point deviation. The data were tested for normality using the Shapiro-Wilk test. When the data followed a normal distribution, a paired sample t-test was employed for the comparison between preoperative and postoperative data. When the data did not follow a normal distribution, the Wilcoxon signed-rank test for paired samples was used for preoperative and postoperative comparison. The study included 18 children with type IIB and III CFM, 11 in the MDO group and 7 in the bone grafting group. In the MDO group, postoperative Gn-FH and Gn-Cor distances increased significantly, whereas the postoperative Gn-Mid distance decreased significantly. Occlusal cant decreased significantly and ramus height affected/unaffected ratio increased significantly after MDO. In the bone graft group, there was no statistically significant difference in the postoperative ratios of chin deviation, occlusal cant, and ramus height affected/unaffected compared to the preoperative values. Compared to bone grafting, MDO can significantly enhance ramus height ratio, level occlusal plane, and centralize the chin point among patients with CFM. Furthermore, MDO achieves superior enhancements in facial symmetry.

Analysis of Obstructive Sleep Apnoea in Craniofacial Microsomia Based on Polysomnography.

OBJECTIVE: This study aimed to investigate the prevalence of obstructive sleep apnoea (OSA) in patients with craniofacial microsomia (CFM) through polysomnography (PSG) and the relationship with the severity of CFM. METHODS: This study reviewed patients of CFM with pre-operative PSG data between January 2005 and September 2023. Patients were grouped according to the Pruzansky-Kaban classification. OSA was diagnosed and severity was assessed by the obstructive apnea-hypopnea index. The Pediatric Sleep Questionnaire was used to investigate OSA-related signs and symptoms. The χ 2 test and Fisher's exact test were used to compare between groups. Univariate logistic regression was used to identify risk factors associated with OSA. A p-value less than 0.05 was considered statistically significant. RESULTS: A total of 121 patients with CFM were included in the study with 3 bilateral and 118 unilateral patients. In total, 86 patients (71.07%) were diagnosed with OSA. The prevalence of OSA in type IIa, type IIb and type III was 72.97%, 78.33%, and 47.62%. There was no statistically significant difference in the prevalence of OSA between type IIa and type IIb (p > .05). The difference in the prevalence of OSA between type III and type II was statistically significant (p < .05). Snoring was the most common symptom among the patients of CFM with OSA. CONCLUSIONS: Patients with CFM have a higher incidence of OSA based on PSG in type II and type III patients. The incidence of OSA did not correlate positively with the severity of CFM, with type III patients having certain particularities.

A Novel Method for one-Stage Repair of the lip Vermilion Defects in Progressive Hemifacial Atrophy.

BACKGROUND: Progressive hemifacial atrophy often causes lip vermilion defects in patients. In this study, we described a one-stage repair method for lip defects in progressive hemifacial atrophy using a lip vermilion mucosal flap or combined dermal fat flap graft. PATIENTS AND METHODS: Patients diagnosed with progressive hemifacial atrophy with lip vermilion defects from 2010 to 2022 were included in this study. Based on the severity and location of the patient's lip defect, a lip vermilion mucosal flap was designed and transferred to the lip defect or combined with a hip dermal fat flap for one-stage repair of the lip morphology. Lip morphology and function of patients were followed up after surgery. RESULTS: A total of 22 patients were enrolled in this study, including 15 patients with lip defects on the upper lip alone and 7 patients with both upper and lower lip defects. Follow-up six months to two years postoperatively, all patients recovered uneventfully without complications. The repaired lips of the patient had a full and symmetrical morphology with no visible scarring. Two patients experienced transient dysesthesia of the lips postoperatively and both returned to normal after three months. All patients had good lip closure with normal dietary and speech function. CONCLUSIONS: The method we described for repairing lip defects in progressive hemifacial atrophy can achieve satisfactory aesthetic and functional lip results. The distinct advantage of this approach is that the patients undergo only one-stage operation and it can be used to repair both upper and lower lip defects.

Condylar resorption post mandibular distraction osteogenesis in craniofacial microsomia: A retrospective study.

The aim of this study was to investigate the characteristics of condylar resorption in craniofacial microsomia (CFM) patients following mandibular distraction osteogenesis (MDO). Patients with unilateral type-IIa and type-IIb CFM, who had completed MDO and mandibular distractor extraction (MDE), were recruited. The height and volume of the condyle were measured on three-dimension models created by the analysis of computed tomography (CT) data. Normality analysis was performed using the Shapiro-Wilk test. Data for the affected and unaffected sides were compared using the paired t-test or Wilcoxon signed-rank test. Data for both type-IIa and type-IIb CFM were compared using the independent-samples t-test or Mann-Whitney U test. The Pearson or Spearman correlation was used to determine the correlations of condylar resorption rate with related measurements. In total, 48 type-IIa and 48 type-IIb CFM patients were included. The condylar resorption rate in type-IIa CFM (0.35 ± 0.32) was significantly associated with the height of the condyle (r = 0.776, p < 0.001) and distraction distance (r = 0.447, p = 0.001), while the condylar resorption rate in type-IIb CFM (0.49 ± 0.46) was significantly associated with the height of the condyle (r = 0.924, p < 0.001). However, there was no significant difference in condylar resorption rate between type-IIa and type-IIb CFM (p = 0.075). In addition to occlusal changes, no other negative symptoms of the TMJ were observed with condylar resorption. Condylar resorption was evident in CFM patients following mandibular distraction osteogenesis, and the condylar resorption rate showed a relationship with distraction distance and condylar height.

Respiratory outcome of mandibular distraction osteogenesis on obstructive sleep apnea in craniofacial microsomia: A retrospective study.

This study aimed to evaluate the effect of mandibular distraction osteogenesis (MDO) on respiratory function in CFM patients with obstructive sleep apnea (OSA) according to polysomnography (PSG). This study retrospectively analyzed patients with CFM who underwent PSG before surgery and after completion of mandible distraction. Patients who met the inclusion criteria were selected. The Pediatric Sleep Questionnaire (PSQ) was used to assess patients' signs and symptoms related to OSA. The obstructive apnea-hypopnea index (OAHI) and lowest oxygen saturation (LSaO2) were imported into SPSS version 26.0. The Wilcoxon signed-rank test was used to assess the differences in PSG before and after MDO. Other data were described using descriptive statistics. A P-value less than 0.05 was considered statistically significant. A total of 25 unilateral CFM patients were included in this study. Most patients (72%) had mild OSA; moderate and severe OSA were 12% and 16%, respectively. Snoring (52%) was the most common symptom among these patients. After completion of mandibular distraction, snoring and other OSA-related symptoms were significantly improved. Twelve patients had normalized PSG and the severity of OSA improved significantly in 3 patients. The total effective rate of MDO for OSA was 60%. The statistical results showed that OAHI (P = 0.045) decreased and LSaO2 (P = 0.009) increased significantly compared to preoperative values. MDO can improve OSA-related symptoms in CFM patients. In addition, respiratory function was improved in most patients after MDO, based on PSG. CFM patients, especially those with OSA, can benefit from MDO.

Morphologic Changes of the Temporomandibular Joint in Pruzansky-Kaban Type IIa Hemifacial Microsomia Postmandibular Distraction Osteogenesis.

OBJECTIVE: Mandibular distraction osteogenesis (MDO) is a powerful tool for the correction of hemifacial microsomia (HFM). The temporomandibular joint (TMJ) is the focus of attention in the diagnosis and treatment of HFM. This observational retrospective cross-sectional study aimed to investigate morphologic changes in TMJ post-MDO in type IIa HFM. METHODS: We recruited 48 patients with unilateral type IIa HFM who had completed MDO and mandibular distractor extraction (MDE). Data relating to the length, distance, angle, and volume of the TMJ were measured on 3-dimension models created by the analysis of computed tomography data. Normality analysis was performed by using the Shapiro-Wilk test. Data were compared with the paired t test and Wilcoxon signed-ranks test. RESULTS: The spaces between the affected condyle and the affected glenoid fossa before MDO were all significantly larger than before MDE (P<0.05). The breadth of the affected glenoid fossa before MDO was significantly longer than before MDE (P<0.001). The height of the affected condyle before MDO was significantly longer than before MDE (P<0.001). The volume of the affected condyle before MDO was significantly larger than before MDE (P<0.001). The ratio between the volume of the affected condyle and unaffected condyle before MDO was 0.20±0.13. The ratio between the volume of the affected condyle before MDE and MDO was 0.65±0.32. The resorption rate of the affected condyle post-MDO was 0.35±0.32. CONCLUSION: Herein, we characterized anatomic changes of the TMJ in type- IIa HFM post-MDO. Condylar resorption and the compression of space between the condyle and the glenoid fossa on the affected side were 2 typical manifestations. Our findings enhanced the understanding of the application of MDO on HFM.