Vascularized fascial flap for reconstruction of combined oral mucosa-mandibular defects: The multi-modal biological assessment.

OBJECTIVE: The reconstruction of composite defects in the oral and maxillofacial region using vascularized fascial flaps, such as the fibular, iliac, and temporal fascial flaps, has gained increasing attention among surgeons. However, there remains uncertainty regarding the suitability of fascial flaps as transplants, as well as their healing processes and outcomes, due to their non-mucosal nature. This study aims to comprehensively assess the biological aspects of vascularized fascial flaps at clinical, histological, and genetic levels, with the goal of providing essential biological references for their clinical application. STUDY DESIGN: This study enrolled three patients who underwent reconstruction of combined oral mucosa-mandibular defects using fibular vascularized fascial flaps between 2020 and 2023. Data regarding changes in the appearance of the fascial flaps, bulk-RNA sequencing, and histological slices of initial fascia, initial gingiva, and transformed fascia were collected and analyzed. RESULTS: Within three months, the fascial flaps exhibited rapid epithelial coverage and displayed distinct characteristics resembling mucosa. High-throughput RNA sequencing analyses and histological slices revealed that the transformed fascia exhibited tissue structures similar to mucosa and demonstrated unique advantages in promoting blood vessel formation and reducing scarring through the high-level expression of relevant genes. CONCLUSION: These findings emphasize the potential and feasibility of utilizing vascularized fascial flaps for oral mucosa reconstruction, establishing their unique advantage as transplant materials, and providing significant biological information and references for their selection and clinical application.

Innovative principle of implant-oriented fibula placement in mandibular reconstruction using double-barrel fibula and simultaneous implants: A technical note.

Simultaneous or secondary inserted implants with double-barrel fibula to reconstruct the mandible have become a common method. However, difficulties in later restoration caused by placement errors of fibula or incipiently placed implants have also been reported in some studies. This note describes a novel technique of implant-oriented guide plates helpful for mandible ablation, fibula segmentation and positioning, and implant placement. We design a series of guide plates especially an implant-fibula placing guide plate, and record and fix the relative spatial positions of the remaining teeth, the simultaneous implants and upper fibula. During surgery, the placement of upper fibula is oriented towards appropriate placement of implants. Therefore, the position of upper fibula can meet the requirements of simultaneous implant as much as possible. Within the limits of present observation, we believe that this technique may increase the manipuility while reducing the errors and the risk of complications.

Maxillary sinus volume and facial asymmetry after unilateral zygomaticomaxillary complex fracture reduction with 2, 3, and 4 fixation points: CBCT-based investigation.

PURPOSE: This study aimed to assess the maxillary sinus volume (MSV), Chronic Sinusitis incidence, and asymmetry of the zygomaticomaxillary complex (ZMC) following ZMC fracture surgery with various numbers of fixation points. MATERIALS AND METHODS: In a prospective non-randomized cohort, 50 adults with unilateral ZMC fractures who treated by open reduction and internal fixation (ORIF) between November 2019 and October 2021 were assigned to accomplish this study. They distributed into three groups as per fixation points (2, 3, or 4 Points). Preoperative (T1), Immediate postoperative (T2), and follow-up (T3) cone beam computed topography were analyzed using the Mimics software. The main measures were MSV and asymmetry indexes (ASI) of six paired bilateral anatomical landmarks (Orbital, Suprajugal, Jugale, Zygon, Maxillozygion 1, and Maxillozygion 2). RESULTS: MSV decreased significantly on the affected sides postoperatively in 2P and 3P groups, both in T2 and T3. Further, the T2-T3 comparisons showed a significant MSV change (p = 0.001). ASI reduced considerably to clinically tolerated levels (<3 mm) on landmarks near the fixation sites postoperatively. The ASI on the Zygon and Maxillozygion 1 landmarks showed significant changes among the three groups in both T2 and T3. Interestingly, only five cases had reported postoperative sinusitis symptoms. CONCLUSIONS: Although the MSV was changed among the different fixation point groups, the incidence of chronic sinusitis was uncommon. Bilateral asymmetry affected by number and position of the fixation points, fixation with 4 points provide more symmetry.

Three dimensional condylar positional and morphological changes following mandibular reconstruction based on CBCT analysis: a prospective study.

OBJECTIVE: This study aimed to evaluate the condylar positional changes following mandibular reconstruction with preservation of the condylar head using Cone-Beam Computed Tomography (CBCT). Also, to assess joint space changes and the overall volumetric space compared to the preoperative status. METHODOLOGY: This prospective study included 30 patients (60 joints) subjected to unilateral mandibular resection and reconstruction with preservation of the condylar head. The Helkimo index and preoperative (T1), two weeks postoperative (T2), and follow-up CBCTs (T3) after at least six months were gathered and processed to evaluate the condylar position and TMJ joint space using Anatomage Invivo 6. A student's t-test and repeated-measures ANOVA statistics were used. A P value of less than 0.05 was considered statistically significant. RESULTS: Thirty patients (14 males, 16 females) with a mean age of 40.01 ± 12.7 years (a range of 18.1-62.9 years) were included. On the tumor side, there were significant variances in the vertical and mediolateral condylar positions between the three-time points (T1, T2, T3). Immediately after the operation, the condyles were significantly displaced in a downward direction at T2, which became larger after the last follow-up period (T3) (p = 0.007). The condylar positions at the anteroposterior direction were relatively stable without significant differences between the three times points (p = 0.915). On the non-tumor side, the condylar positions were relatively stable in the mediolateral and anteroposterior positions. In the tumor side, all of the TMJ spaces were significantly increased in size following the mandibular reconstructions (T2 and T3). However, on the non-tumor side, the anterior, posterior, and medial joint spaces were significantly changed postoperatively. CONCLUSION: After mandibular reconstruction with condylar preservation, the condylar position and volumetric measurement immediately changed noticeably and continued to be a permanent change over time compared to relatively stable condyles on the non-tumor side. According to Helkimo index, patients become adapted to the postoperative changes without significant differences between the two sides.

Is the retromandibular approach a suitable approach to anatomical reduction of unilateral subcondylar fracture? A non-randomized clinical trial.

The aim of this study was to evaluate the efficacy of the retromandibular approach (RMA) to produce three-dimensional (3-D) reduction of the unilateral subcondylar fracture and Temporomandibular Joint (TMJ) functional implication. METHODS:  A prospective cohort study was designed. Twenty-nine patients with unilateral subcondylar fracture underwent consecutively Open Reduction, and Internal Fixation. The cohorts were divided into two groups; RMA group (n = 16, 55.17%) and submandibular approach SMA group (n = 13, 44.82%). The primary outcome was the anatomical 3-D reduction of the condyle. The secondary outcome was to compare the condyle position and inclination finding with TMJ outcomes. Helkimo Index score was used to evaluate the TMJ outcome at six months postoperatively. RESULT:  There was a significant difference between the mediolateral condylar inclination, condylar medial and vertical positions when RMA compared with SMA groups (P < 0.05). The medial joint space was correlated with the medial condylar position in both groups (P < 0.05). The Helkimo Ai and Di was associated with mediolateral condylar inclination in SMG; however, Helkimo Ai was found to be correlated with the RMA group. CONCLUSION:  The current study demonstrates that the RMA could re-establish the anatomical position of the unilateral subcondylar fracture in patients undergoing ORIF. The clinical outcome of the TMJ with RMA was better than SMA.