Digitally driven surgical guide planning.

To investigate the role of a fully digital process in the surgical treatment of mandibular fractures in children. We analyzed a complete dataset from 22 children with mandibular fractures treated with digital surgical assistance. The patient's treatment process included preoperative thin layer CT (Computed Tomography) scanning, computer-aided design (3D reconstruction, virtual reduction, and internal fixation device determination and shaping), and 3D printing (jaw model, bite plate). We used occlusal and shaping plates during surgery to assist in fracture reduction and fixation. During the follow-up, we observed the occurrence of fracture healing, occlusal relationships, opening degrees, and complications in pediatric patients after surgery. Next, we used the 3D overlay function of MIMICS software to compare the preoperative surgical design with postoperative jaw imaging data to evaluate the overall surgical effect. The postoperative imaging data showed good fracture healing, normal occlusion during follow-up, and significant improvement in opening degrees. The mean preoperative opening degree was 23.59 ± 2.89 mm, and the mean postoperative opening degree was 29.82 ± 1.79 mm; there was a significant difference between these two parameters (p < 0.05). There were no complications such as tooth germ injury, nerve injury or fracture block displacement. The postoperative mandibular imaging data was imported into MIMICS software for 3D overlay visualization, and the postoperative mandibular morphology recovery was well-matched with the preoperative design. We measured the average upper deviation (0.65 ± 0.09) mm and the average lower deviation (-0.57 ± 0.14) mm. The fully digital process has a precise, minimally invasive, and safe effect in the surgical treatment of mandibular fractures in children, and the clinical effect is satisfactory.

Mutations of PTCH1 gene in two pedigrees with bifid rib-basal cell nevus-jaw cyst syndrome. / 肋骨分叉-基底细胞痣-é¢Œéª¨å›Šè‚¿ç»¼åˆå¾ä¸¤å®¶ç³»åŸºå› åºåˆ—å˜å¼‚åˆ†æž.

Two male patients with bifid rib-basal cell nevus-jaw cyst syndrome (BCNS) were admitted to Department of Stomatology, the First Affiliated Hospital of Bengbu Medical College due to radiological findings of multiple low density shadows in the jaw. Clinical and imaging findings showed thoracic malformation, calcification of the tentorium cerebellum and falx cerebrum as well as widening of the orbital distance. Whole exon high-throughput sequencing was performed in two patients and their family members. The heterozygous mutations of c.C2541C>A(p.Y847X) and c.C1501C>T(p.Q501X) in PTCH1 gene were detected in both patients. Diagnosis of BCNS was confirmed. The heterozygous mutations of PTCH1 gene locus were also found in the mothers of the two probands. Proband 1 showed clinical manifestations of low intelligence, and heterozygous mutations of c.C2141T(p.P714L) and c.G3343A(p.V1115I) were detected in FANCD2 gene. Proband 2 had normal intelligence and no FANCD2 mutation. The fenestration decompression and curettage of jaw cyst were performed in both patients. Regular follow-up showed good bone growth at the original lesion, and no recurrence has been observed so far.

Clinical Application of Digital Joint Guide in the Fracture of the Condyle Neck.

PURPOSE: The purpose of this study is to use a digital guide plate for joint positioning to assist the reduction of condylar neck fractures and evaluate the accuracy of the reduction after surgery. MATERIALS AND METHODS: In this study, 20 patients were selected from January 2016 to October 2020, and the reduction of the mandibular condyle neck fracture was designed virtual and digital based on the computed tomography data of the patients, based on the position of the condyle in the articular socket, the height of the ascending mandibular ramus, and the joints. The average value of the anterior space and the posterior space of the joint is these indicators, the position of the condyle is reconstructed, and the fracture reduction finger guide plate is designed. During the operation, the digital guide plate is used to assist the reduction of the condyle neck fracture. The postoperative follow-up was 4 to 12 months to check the accuracy of the reduction. RESULTS: A total of 20 patients, all fractures achieved complete bone healing, the patients' mouth opening was normal, no obvious complications were found, and none of the patients had facial paralysis. In the postoperative evaluation and preoperative virtual design plan, the chromatographic error was within 2 mm, and the magnetic resonance of the temporomandibular joint showed no displacement of the articular disc. CONCLUSION: The digital joint guide can reduce the fracture of the condyle neck while ensuring the position of the condyle in the joint socket, which is beneficial to reduce the occurrence of subsequent temporomandibular joint complications.

[Application of personalized guide plate combined with real-time navigation in repairing mandibular defect using fibula muscle flap].

Objective: To explore the application of personalized guide plate combined with intraoperative real-time navigation in repairing of mandibular defect using fibula muscle flap, providing the basis for the precise repair and reconstruction of mandible. Methods: The clinical data of 12 patients (9 males and 3 females) aged from 23 to 71 years (mean, 55.5 years) between July 2019 and December 2021 were recorded. These patients were diagnosed as benign or malignant mandibular tumors, including 2 cases of ameloblastoma, 6 cases of squamous cell carcinoma, 2 cases of osteosarcoma, 1 case of adenoid cystic carcinoma, and 1 case of squamous carcinoma. All patients were treated with mandibular amputation, and then repaired by double-stacked three-segment fibula muscle flap. Preoperative virtual design scheme and guide plate were performed. During the operation, personalized guide plate combined with real-time navigation was used for fibular osteotomy and shaping. Thin-slice CT examination was performed at 2-3 weeks after operation, and was fitted with the preoperative virtual design scheme. The difference between the distance of bilateral mandibular angles relative to the reference plane in three-dimensional directions (left-right, vertical, and anterior-posterior) and the difference of the medial angle of the lower edge of the mandible reconstructed by fibula were measured, and the mean error of chromatographic fitting degree was calculated. Results: The guide plate and navigation were applied well, and the fibula shaping and positioning were accurate. The fibula muscle flap survived, the incision healed well, and the occlusal relationship was good. All 12 patients were followed up 1-29 months, with an average of 17 months. There was no significant difference on the distance of bilateral mandibular angles relative to the reference plane in the left-right [(-0.24±1.35) mm; t=-0.618, P=0.549], vertical [-0.85 (-1.35, 1.40) mm; Z=-0.079, P=0.937], and anterior-posterior [(-0.46±0.78) mm; t=-2.036, P=0.067] directions. The difference of the medial angle of the lower edge of the mandible reconstructed by fibula was also not significant [(-1.35±4.34)°; t=-1.081, P=0.303)]. Postoperative CT and preoperative virtual design fitting verified that there was no significant difference in the change of the mandibular angle on both sides, and the average error was (0.47±1.39) mm. Conclusion: The personalized guide combined with intraoperative real-time navigation improves the accuracy of peroneal muscle flap reconstruction of the mandible, reduces the complications, and provides a preliminary basis for the application of visual intraoperative navigation in fibula muscle flap reconstruction of the mandible.

The clinicopathological features of parotid lymphoma.

Lymphoma of the parotid gland is a rare malignant tumor, and cohort studies on the survival rates of affected patients are sparse. This study aimed to retrospectively evaluate the clinicopathological characteristics of patients diagnosed with non-Hodgkin lymphoma of the parotid gland. This study included 31 patients diagnosed with lymphoma of the parotid gland. Data on the pathological subtypes, the WHO classifications of the hematopoietic and lymphoid tissues, and the Ann Arbor staging, treatment modalities, and survival times were collected and analyzed. Among the 31 patients, there were 18 cases of extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT), 7 cases of diffuse large B-cell lymphoma (DLBCL), and 6 cases of follicular lymphoma (FL). The tumors were most-commonly located in the superficial lobe of the parotid gland (28/31), and three cases involved the deep lobe of the parotid gland (3/31). The overall median survival from the diagnosis of lymphoma was estimated to be 62 months, with 3-year and 5-year survival rates of 83.9% and 77.4%, respectively. A univariate analysis demonstrated statistically significant differences in accelerated tumor growth (P<0.001) and the presence of tumor capsules (P<0.001). A multivariate analysis demonstrated statistically significant differences in the accelerated tumor growth (P=0.029). MALT lymphoma was the most common subtype of primary parotid lymphoma. The prognosis is better than it is with other malignant parotid tumors. The presence of accelerated tumor growth was significantly correlated with overall survival time.