The progress and development of new surgical techniques, imaging technology, and back-fill materials have greatly improved the success rate in endodontic surgery. At the same time, doctors have also begun to pay attention to the aesthetic defect of gingiva following surgery, such as gingival recession, "black triangles", and scar formation. Previous scholars believed that different incision designs had varying effects on postoperative gingival aesthetics, but in recent years, there have been few literature reports on this topic. Starting from the characteristics and indications of different incision designs, this article reviews the impact of incision types on the aesthetic effect of gingiva after apical surgery and related evaluation indicators, in order to provide some references for selecting appropriate incision designs in clinical work.

Head and neck squamous cell carcinoma (HNSCC) is the most prevalent cancer of the head and neck which exhibits significant heterogeneity, and its etiology remains incompletely understood. Single-cell transcriptome sequencing enables unbiased, high-throughput and high-resolution transcriptome sequencing to obtain relevant data and perform information analysis at the single-cell level, which has become a powerful tool to understand the molecular mechanisms of the development of HNSCC and to develop new strategies for prevention and treatment. This review summarized the important study and latest achievements of single-cell transcriptome sequencing in the characterization of tumor microenvironment, tumor invasion and metastasis, human papilloma virus (HPV⁺) and HPV^- infection of HNSCC, and immunotherapy, aiming to provide new ideas for the research, diagnosis, and treatment of HNSCC.

Orthodontic tooth movement is a key step in clinical orthodontic treatment. By applying appropriate orthodontic forces to the teeth, these forces are transmitted to the periodontium, causing adaptive remodeling of the surrounding soft and hard tissues. The transient receptor potential vanilloid 4 channel (TRPV4) is a mechanically sensitive calcium channel protein with multiple functions and complex mechanisms. It plays an important role in the transmission of mechanical forces, inflammatory responses, and other aspects. In recent years, researchers have found that the TRPV4 channel is also involved in orthodontic tooth movement. This article provides a review of the role of the TRPV4 channel in orthodontic tooth movement,aiming to provide a foundation and theoretical basis for clinical orthodontic treatment of tooth movement.

Objective: To evaluate the changes of tongue morphology in skeletal Class Ⅲ patients after bimaxillary orthognathic surgery, and to explore the relationships between the changes of tongue morphology and the sagittal movement distance of maxilla and mandible. Methods: Thirty-five patients with skeletal Class Ⅲ malocclusion who underwent LeFort I osteotomy and bilateral sagittal split mandibular osteotomy were included in this retrospective study. Spiral CT was collected 1 week before operation (T0), 1 month after operation (T1), and 6-12 months after operation (T2). The tongue position, length, height, area, and volume in oral cavity proper were measured. The data in T0, T1, and T2 were compared. The relationships between the changes of tongue morphology and the sagittal movement distance of maxilla and mandible were analyzed. Results: After orthognathic surgery, the tongue position in oral cavity proper was more backward and upward. The L2, L3, and L4 distance increased significantly at T1 and T2, and the amount of increase were (2.08±2.76) mm, (1.88±2.48) mm, and (1.64±2.31) mm at T2 compared with T0, respectively. At T1, the tongue height increased significantly, and the tongue sagittal position measurement, tongue length, and tongue volume in oral cavity proper decreased significantly compared with T0. At T2, the tongue height returned to T0 level, but the tongue sagittal position measurement, tongue length, and tongue volume in oral cavity proper still decreased significantly, and the amount of decrease were (4.41±5.53) mm, (4.81±6.96) mm, and (6.04±13.62) cm³ compared with T0, respectively. The change degree of the tongue sagittal position measurement and the tongue volume in oral cavity proper between T2 and T0 was positively correlated with the sagittal movement distance of supramentale (r=0.394, r=0.452). Conclusion: After bimaxillary orthognathic surgery, the relative position of the tongue in oral cavity proper was more backward and upward, while the tongue volume in oral cavity proper decreased. It suggests that the tongue underwent adaptive changes.

Objective: To summarize and analyze the cases of mandibular defects caused by various reasons in the maxillofacial surgery team of our hospital in recent years, and compare the advantages, disadvantages, and clinical effects between vascularized free fibular flap and iliac flap. Methods: A retrospective study was conducted on 59 cases of vascularized free fibular and iliac flaps for repairing mandibular defects. The indications, perioperative information, and prognosis of vascularized free fibular and iliac flaps for repairing mandibular defects were evaluated and compared. Results: Twenty-seven cases of fibular flap and 32 cases of iliac flap survived, and there was no significant difference in general information, facial appearance, and oral function recovery (6 months after surgery) between two groups. There were significant differences in the type and length of mandibular defect, surgical time, ICU hospitalization time, and postoperative hospitalization time. Conclusion: For mandibular angle defects, vascularized free iliac flap repair is prioritized, while for defects crossing the midline, vascularized free fibular flap repair is prioritized. The Brown classification method can effectively guide the selection of bone flap types. For defects larger than 90 mm, priority should be given to fibular repair, and skin islands can be carried simultaneously to repair soft tissue defects. For defects smaller than 90 mm without soft tissue defects, priority should be given to iliac bone repair. For defects smaller than 90 mm with soft tissue defects, tensor fascia lata flap should be carried for repair. The vascularized free iliac flap is significantly better than the vascularized free fibular flap in terms of surgical time, ICU hospital stay, and postoperative hospital stay. Both vascularized free fibular and iliac flaps can effectively restore the patient's facial appearance and oral function without significant differences.

Objective: To summerize the imaging and clinical features of MRONJ (medication-related osteonecrosis of the jaw) by comparing with suppurative osteomyelitis of the jaw. Methods: The imaging and clinical data of patients with MRONJ were retrospectively analyzed with those of patients with suppurative osteomyelitis of the jaw. Results: In the cases of MRONJ, 100% (compared to 14.0% of suppurative osteomyelitis of the jaw) were observed with osteosclerosis, 30.8% (compared to 5.0%) were observed with multiquadrant osteosclerosis, 43.6% (compared to 4.0%) were observed with sequestrum, 25.6% (compared to 0%) were observed with sequestrum and multiquadrant osteosclerosis, and 89.7% (compared to 20.0%) of the inducements were tooth extraction. Conclusion: Compared to suppurative osteomyelitis of the jaw, the probability of oberving osteosclerosis, multiquadrant osteosclerosis, and sequestrum on MRONJ are higher, and when multiquadrant osteosclerosis and sequestrum appear simultaneously, it is very likely to be MRONJ. Tooth extraction is the most major inducement of MRONJ.

Objective: To explore the risk factors and evaluate survival rates in patients undergoing root canal treatment for irreversible pulpitis in primary molars under local anesthesia through clinical follow-up data. Methods: Clinical follow-up data of patients aged 3-8 years old diagnosed with irreversible pulpitis and treated with root canal therapy on primary molars between April 2018 and June 2022 at the Children's Stomatology Department of Hefei Stomatology Hospital were collected. Kaplan-Meier method and Cox regression analysis were employed for survival analysis. Results: A total of 255 patients with 377 primary molars were included in the study. It was found that the older the children, the greater the risk of treatment failure(hazard ratio: 1.688, 95% confidence interval: 1.059 - 1.889). Maxillary primary molars had a higher success rate compared to mandibular primary molars. Glass ionomer cement (GIC) filling was associated with a higher failure risk, while differences in success rates were not statistically significant in treatment times and gender (P>0.05). Conclusion: Age, tooth position, and restoration materials are important factors affecting the success rate of root canal treatment in deciduous molar teeth.

Objective: To investigate the incidence and clinical characteristics of maxillary deciduous fused incisors by panoramic radiographs. Methods: A total of 76288 panoramic radiographs of subjects aged 3 to 8 years old in the image database of our hospital were collected from January 2018 to December 2023, and the incidence of maxillary deciduous fused incisor was observed, as well as the abnormalities in inherited permanent teeth of fused teeth were also recorded. Results: The incidence of maxillary deciduous fused incisors was 0.21% (153/76288). There were more fused teeth in boys than girls (P＜0.05), and more fused teeth in unilateral than bilateral (P＜0.01), but the difference between left and right sides of fused teeth was not statistically significant (P>0.05). Of the 153 fused teeth, 138 subjects had normal number of maxillary deciduous incisors and 15 subjects had supernumerary deciduous teeth. In 138 subjects, 74.15% of them had congenital inherited permanent teeth absence. In the maxillary permanent incisors without missing, 42.11% had microdontia and 36.84% had delayed tooth development. In 15 subjects of maxillary supernumerary deciduous teeth, 20.00% had supernumerary teeth in permanent dentition. There were 2 subjects with triple teeth of maxillary deciduous incisors. Conclusion: Maxillary deciduous fused incisors are usually fused with 2 teeth, and triple teeth are rare. The fused teeth of maxillary deciduous incisor are more male than female, and unilateral than bilateral. Fused teeth affect the length of dental arch, teeth arrangement, and even appearance, and often are associated with abnormalities of permanent teeth and permanent dentition.

Objective: To analyze the clinical application effect of metal preformed full crown distal shoe space maintainer in premature loss of the primary second molar. Methods: From January 2021 to January 2024, 89 children with premature loss of the primary second molar restored by metal preformed full crown distal shoe space maintainer in Hefei Stomatological Hospital West were collected.Clinical and imaging data were retrospectively analyzed at least 1 year after surgery.The effect of clinical treatment was analyzed from four aspects: retention rate, retention status, loss of space, and maintenance time. Results: The data of 57 patients who completed follow-up to distal shoe space maintainer (DSSM) were analyzed. Average maintenance time was 15(12.5,18.0) months and 16 cases appeared fall off or removed in advance. Chronic inflammation of the first primary molarand the DSSM desoldering were risk factors of the retention failure (P<0.05). Chronic inflammation of the first primary molar was risk factors of the retention status (P<0.05). Data of 84 patients with 1-year follow-up were analyzed. It was found that the average gap loss of 22 cases with DSSM position deformation was 2.31mm, however, 62 cases with good position was 0.13mm.The difference between the two groups was statistically significant (P<0.05). Conclusion: The metal preformed full crown distal shoe space maintainer treatment in premature loss of the primary second molar had a good retention rate. Good gap preservation clinical results were also achieved in well-positioned cases. Preoperative diagnosis and treatment of chronic inflammation of the first primary molar and occlusal management should be improved.

Objective: To analyze the clinical features of maxillofacial fractures in children and adolescents, and to conduct a preliminary study on the fracture accompanying traumatic dental injury (TDI). Methods: The data of patients with maxillofacial fractures aged 0-18 years from the First Affiliated Hospital of Bengbu Medical University from January 2018 to December 2023 were collected.The age, gender, trauma cause, fracture site, treatment method and TDI were classified. Results: One hundred and eighty-six patients were included. There were statistical differences in fractures caused by falling, motor vehicle-person traffic accidents, and falling down among three age groups (P<0.05). The surgical treatment rates of fractures in the 3 age groups were 35.00%, 50.00%, and 66.96%. There were 96 patients (51.61%) with fracture accompanied by TDI. The most common tooth position was central incisor (41.93%), and the common injury type was periodontal tissue injury (68.32%). The rate of tooth loss was 31.37%. Conclusion: Trauma causes and treatment of maxillofacial fractures in children and adolescents are characterized by age distribution. Fractures accompanied by TDI are common and frequent, and the rate of tooth loss is high. The timeliness and accuracy of diagnosis and treatment should be improved.

Objective: Observe the changes of periodontal hard tissue in adult orthodontic patients with sagittal retraction of mandibular anterior teeth at different stages of orthodontic treatment, and to analyze the correlation between the change of labial and lingual inclination of mandibular anterior teeth and the incidence of labial bone dehiscence. Methods: Twenty adult patients with sagittal retraction of mandibular anterior teeth during orthodontic treatment were selected,imaging data were collected before orthodontic treatment (T0), 10 months of orthodontic treatment (T1), and 20 months of orthodontic treatment (T2).Imaging examination measured: (1) labial bone thickness (LBT) at 3mm, 5mm, and 7mm of the root of cemeto-enamel junction (CEJ); (2) Correlation analysis between intraoperative dehiscence (DEH) and the change of L1-mandibular plane (L1-MP). The data at the three time points were compared and analyzed to reveal the effect of sagittal retraction of mandibular anterior teeth on periodontal tissue. Results: Our imaging examination showed that during orthodontic treatment, LBT at 3 mm, 5 mm and 7 mm of CEJ root decreased first and then increased, where LBT was lower at T1 than at T0 (P<0.05), and higher at T2 than T1 (P<0.05), indicating that the amount of bone loss in the early stage of orthodontic treatment was significantly higher than that in the late stage.At T1, LBT at 3mm of CEJ root of central incisor decreased significantly (P<0.05), indicating that bone loss of central incisor root neck was the most significant in the early orthodontic treatment. At T0 and T2, the change of inclination was positively correlated with the incidence of labial bone dehiscence. The incidence of canine dehiscence was the highest during orthodontic treatment. Conclusion: (1) The early sagittal retraction of anterior teeth under adult orthodontics has a greater impact on periodontal hard tissue, which will lead to a decrease in the thickness of the labial alveolar bone and an increase in the incidence of bone dehiscence. (2) Periodontal tissue also has certain compensatory ability. In the later stage of the experiment, the thinned labial alveolar bone thickened. At the end of the observation period, by comparing various research indicators in different periods, it was proved that the compensatory ability of periodontal tissue was far from enough to make up for the damage caused by orthodontic treatment. (3) The bone loss of the mandibular central incisor at neck of roor is the largest during the sagittal retraction of mandibular anterior teeth in adult orthodontics, and the incidence of canine bone dehiscence is the highest. For these sites with high potential risks, periodontal real-time monitoring should be carried out to prevent and reduce the loss of periodontal tissue through root control and periodontal soft and hard tissue augmentation.

Objective: To evaluate the clinical performance of metal wing lingual retainer. Methods: Twelve patients after orthodontic treatment were selected. Six patients used the lingual retainer of cobalt-chromium alloy wing printed by laser fusion technology, and 6 patients used the lingual wire fixed retainer. All the retainers were bonded to the mandibular teeth by resin adhesive. The bonding operative time were recorded, and the retainer retention and deformation, dentition retention, periodontal health index, and comfort were evaluated at 1, 3, and 6 months after bonding. Results: The chair-side time of metal wing group (5.27±2.58) min was shorter than that of lingual wire group (10.07±2.71 min, P<0.05). The retention and deformation, dentition retention, periodontal health index, and Comfort Index of metal wing group were better than that of lingual wire group (P＜0.05). Conclusion: Metal wing lingual retainer printed by laser fusion technique could meet the clinical requirements.

Objective: To explore the impact of pre-filled resin on the adhesion effectiveness of attachments for invisible orthodontic aligners. Methods: This study involved 60 orthodontic patients from the Department of Orthodontics at Anyang Sixth People's Hospital, including a total of 1002 attachments. The upper jaw was used to compare the attachment loss rates over 6 months between resin pre-filled 72 hours in advance and conventional chairside filled resin, while the lower jaw was used to compare the 24-hour pre-filled resin with the conventional method. Results: Both the upper and lower jaws demonstrated no significant statistical difference in attachment loss rates between the pre-filled groups and their respective conventional chairside filled groups. Conclusion: Pre-filling resin does not affect the adhesion of attachments and can be used to enhance clinical operational flexibility and efficiency.

Objective: To evaluate the accuracy of registration of oral implant robot using five kinds of intraoral scanners. Methods: The registration process of robot-assisted implant surgery was completed by using the oral scanning registration method and the cone beam computed tomography (CBCT) registration method, respectively. The oral scanning registration method used five different intraoral scanners, and then two implants were implanted in the mandibular dentition defect model under the guidance of the robot. CBCT was taken after operation for deviation analysis. The main analysis indexes were implant angle deviation and total deviation of implantation point and apical point. Results: The registration accuracy of the robot under five different intraoral scanners was not statistically significant in implant angular deviation, implant depth and level deviation, and apical depth and level deviation (P>0.05). The total deviation of the entry point and the total deviation of the apical point were statistically significant (P<0.05). Conclusion: The accuracy of oral implant robot registration using five kinds of intraoral scanners can achieve good clinical results, but the registration accuracy of different intraoral scanners is different.

Adequate and healthy soft tissue surrounding the implant is crucial for achieving aesthetic and long-term outcomes in anterior dental implant treatments. This article presents a case study of reconstructing severe soft tissue deficiency in the anterior dental region. Through the use of vascularized interpositional periosteal-connective tissue (VIP-CT) flap, the restoration of soft tissue aesthetics and function was successfully achieved, laying a solid foundation for subsequent implant restoration.

Six years follow up observation was made for a case of immediate implant treatment of a maxillary central incisor. Autologous root graft replantation technique was used in this case, which successfully avoided the absorption of labial soft and hard tissues after maxillary anterior tooth extraction, providing a new solution for dental implant restoration in the anterior esthetic area.

This article reports on a case of a patient with autism spectrum disorder receiving comfort-oriented outpatient dental treatment. The treatment approach aims to provide comfortable oral care, minimizing patient discomfort and anxiety, while delivering effective dental treatment. Through close collaboration with the patient family, improvements in the patient's treatment experience were achieved, resulting in favorable treatment outcomes.

Oral lichenoid drug reactions (OLDR) refer to lichenoid manifestation of the oral mucosa induced by specific drugs in individuals with allergic predispositions. There are numerous types of drugs that can trigger OLDR, but reports on oral lichenoid drug reactions induced by immunotherapy are rare. This manuscript reports a case of OLDR and gingival bleeding induced by atezolizumab and bevacizumab combination anticancer therapy, and explores its clinical features, as well as the diagnostic and treatment approaches. The aim of this case is to provide valuable insights for the clinical management of this disease.