Osteosarcoma is the most common osteogenic malignancy of the head and neck, and its incidence in the upper mandible is predominant. Osteosarcoma of the head and neck has various causes and rich pathological subtypes. Diagnosis of osteosarcoma requires the synthesis of symptoms and imaging data and pathological characteristics (including cell characteristics, immunohistochemical characteristics and molecular markers). Surgery is the core treatment for osteosarcoma of the head and neck. Compartment resection based on the Enneking staging system has high practicability in the surgical treatment of osteosarcoma of the head and neck. Osteosarcoma can be treated by combined craniomandibular surgery to achieve complete resection of the tumor. The combination of adjuvant radiotherapy, adjuvant chemotherapy and surgery can further reduce the risk of local recurrence and distant tumor metastasis. The emergence of targeted therapy and immunotherapy provides more options for the treatment of head and neck osteosarcoma. This article reviews the diagnosis and treatment of osteosarcoma of the head and neck.

Objective : To explore the promoting effect of periostin on rapid distraction osteogenesis of the rabbit mandible and provide experimental evidence for the clinical use of periostin to promote osteogenesis. Methods: Twenty-four New Zealand male white rabbits underwent distraction osteogenesis, and after 3 days of retention, they were rapidly stretched at a stretch rate of 2 mm/d (total 5 d). The animals were randomly divided into group A and group B (12 per group). On the last day of the stretch, 0.5 mL of normal saline containing 40 μg of recombinant periostin was given to group B or an equal volume of normal saline was added to the control group (group A) for 8 days. At 4 weeks and 8 weeks post-stretch, 8 animals were randomly selected from each group to undergo a CT scan under general anesthesia. The bone mineral density and bone mineral content were detected by dual energy X-ray absorptiometry. Eight weeks post-stretch, all of the experimental animals were sacrificed. Six animals were randomly selected from each group for micro-CT and a histological examination, and the remaining animals were subjected to biomechanical tests. Results : CT images showed that the new bone formation in the distraction space of group B was significantly better than that of group A at 4 and 8 weeks post-stretch. At 4 weeks and 8 weeks post-stretch, the bone mineral density in group B was (0.157 ± 0.016) g/cm 2 and (0.234 ± 0.023) g/cm 2, respectively, and the bone mineral content was (0.096 ± 0.010) g and (0.204 ± 0.017) g, respectively. The above four means were significantly higher in group B than in group A (P < 0.001). The micro-CT images and data suggest that the stretch gap microstructure of group B has more mature features. Histological experiments showed that the trabecular bone of group B was thick and mature, with few chondrocytes. The biomechanical test results showed that the biomechanical strength of the distraction gap in group B was (228.47 ± 39.98) N, which was 1.24 times that of group A (P = 0.045). Conclusion Interstitial use of periosteal protein in the distraction space of the mandible in rabbits can promote local new bone formation and mineralization.

Objective: To study the expression and distribution of filaggrin (FLG) in oral submucous fibrosis (OSF) and to explore the significance of FLG in the occurrence and development of OSF. Methods : Ten cases with a normal oral mucosa (normal buccal mucosa group) and 30 cases of tissues with OSF lesions, including 10 cases each in the early (early OSF group), moderate (middle OSF group) and advanced stages (late OSF group), were selected. FLG was analyzed by immunohistochemistry. The FLG-positive cells were counted to calculate the percentages of cells with FLG-positive expression in each group. Results: FLG expression was negative in most of the normal buccal mucosa group specimens and was positive in the OSF buccal mucosal epithelial specimens. With aggravation of the OSF lesion, the number of FLG-positive cells increased. In the early OSF group, FLG-positive expression was mainly concentrated in the granular and keratinized epithelial layers. In the middle OSF group, the number of FLG-positive epithelial cells increased gradually. In the late OSF group, almost all epithelial cells were FLG-positive in the cytoplasmic nucleus. The percentages of FLG-positive cells in the early, middle and late OSF groups were (24.63 ± 9.06)%, (54.23 ± 10.63)% and (83.97 ± 8.72)%, respectively. The percentage of FLG-positive cells was significantly higher in the OSF group than in the normal mucosa group (P < 0.05). Conclusion FLG was expressed at a higher level in the OSF epithelium than in the normal oral mucosal epithelium and was upregulated in the OSF epithelium with aggravation of the OSF lesions. Abnormal FLG expression may be related to the terminal differentiation disorder of OSF epithelial keratinocytes.

Objective : To analyze the value of virtual surgical planning in the surgical treatment of osteoradionecrosis of the mandible and to provide a reference for clinical practice. .Methods : From September 2017 to June 2018, 13 patients with mandibular osteoradionecrosis were evaluated preoperatively using the 3D virtual surgery software CMF Proplan 2.0. The surgical guide was designed and 3D printed. Bone resection, fibula shaping and bone graft localization were completed during the operation. In some cases, implants were implanted at the same time, and denture restoration was completed 3 to 6 months after surgery. Patients’ general information, perioperative data, and efficacy evaluation were analyzed. Results: All patients underwent surgery successfully. The survival rate of the free fibula musculocutaneous flap was 100% (13/13), and one patient had complications (partial necrosis at the edge of the flap). The follow-up period was 7 to 15 months, and the median time was 10 months. All patients achieved a healing effect. The number of cases with an increase in mouth opening ≥ 1 cm, 0.5 cm ≤ mouth opening increase < 1 cm, and mouth opening increase < 0.5 cm were 5, 6, and 2, respectively. An imaging examination showed that 12 patients had good bone healing, and 1 patient did not completely heal 7 months after operation. The denture restoration was 92.3% (12/13), of which 3 cases were implanted and repaired at the same time. The average chewing efficiency was 56.11% ± 7.12% (42.03%-67.83%). Conclusion Virtual surgical planning is an effective method for the surgical treatment of mandibular osteoradionecrosis, which can reduce the risk of surgery and more effectively perform mandibular shape and function repair.

Objective : To explore the clinical effect of simultaneous distraction osteogenesis of the maxilla and affected mandible combined with second-stage orthognathic surgery for the treatment of adult hemifacial microsomia to provide a reference for clinical practice. Methods: Twelve adult patients with hemifacial microsomia who underwent simultaneous distraction osteogenesis and second-stage orthognathic surgery from 2006 to 2013 were enrolled. Distraction osteogenesis of the maxilla and malformed lateral mandible and second-stage orthognathic surgery were performed according to each patient’s specific conditions. The height ratio of the mandibular ramus of the affected side to the contralateral side, the shift distance of the chin point and the inclination angle of the screw plane were measured before and after the operation, and the therapeutic effect was evaluated with clinical photographs. Results : No patients had obvious complications after the operation, the postoperative aesthetic effect was good, and the relationship between the facial shape and occlusion was significantly improved. The cephalometric measurement showed that the height ratio of the mandibular ramus of the affected side to the contralateral side was increased by 23.83% (t=11.658, P<0.001), the deviation distance of the chin was corrected, and the chin point moved back to the midline by 6.63 mm (t=13.042, P<0.001) on average, and the inclination angle of the occlusal plane was improved and returned to the horizontal plane by 8.83° (t=15.358, P<0.001) on average. Conclusion The application of simultaneous distraction osteogenesis of the maxilla and mandible combined with secondary orthognathic surgery for the treatment of adult hemifacial microsomia can obtain satisfactory clinical and aesthetic results and has clinical value.

Objective: To observe the clinical effect of the modified M-shaped flap for repairing defects following resection of lower lip cancer and to provide a reference for clinical application. Methods : Fourteen cases using modified M-shaped flaps to repair lower lip cancer surgery defects were retrospectively analyzed. The postoperative follow-up patients’ flap survival, mouth opening, denture use, bilateral mouth angle symmetry, recurrence and survival were analyzed. Results : Fourteen patients with lower lip cancer underwent reconstruction immediately after surgery, and the defect range after tumor resection was 30% to 50% of the lower lip. The continuity of the orbicularis oculi muscle is reconstructed by modified M-shaped flap to transfer bilateral residual lip tissue. The blood supply to the flap is stable. All patients’ flaps survived completely without complications, such as hemorrhage, infection or flap necrosis, and their lip movement and sensation recovered well. There were no obvious obstacles in opening and closing or pronunciation and dietary function, and the mean maximum opening was (3.06 ± 0.23) cm. Three patients used active dentures, which could be removed normally. All patients’mouths were preserved. Approximately 85.7% of patients (12/14) had bilateral symmetry of the bilateral mouth, the flaps matched the facial color, and the lower lip was naturally beautiful, as the scar was not obvious. After 6 months to 4 years of follow-up (mean 2 years and 6 months), no recurrence or death occurred. Conclusion The modified M-shaped valve design is simple and easy to operate. This method can be applied to 30% to 50% defect reconstructions of the lower lip to retain the corner of the mouth.

Objective: Objective To evaluate the effect of repairing posterior teeth with subgingival defects with onlays after deep margin elevation and to provide a reference for clinical application. Methods : Eighty-six cases of posterior teeth with subgingival defects were treated with resin filling to elevate the subgingival margin to the superior gingival margin and were then restored with onlays of cast porcelain. Patients were followed up at 1 week, 6 months and 12 months. The wear and tear of the restorations, fractures of the restorations, loss of the restorations, marginal closeness, marginal staining, secondary caries and gingival health were examined. Assessment of efficacy with reference to American public health service standards was conducted. Results : One week after the operation, there was no loss of follow-up. Eighty-six cases of onlays had no prosthetic wear, prosthetic fracture, prolapse of the prosthesis, edge adhesion, edge coloration, secondary caries, etc., and the gums were healthy. At 6 months after surgery, 2 patients were lost to follow-up and 4 of the remaining 84 onlays were detached. After re-adhesion, there was no shedding. At 12 months after surgery, 5 cases were lost to follow-up and 81 cases of onlays demonstrated no further prosthetic wear, prosthetic fracture, prolapse of the prosthesis, edge adhesion, edge coloration, secondary caries, etc., and the gums were healthy. The success rate after 12 months of repair was 95.1% (77/81).Conclusion For posterior teeth with a subgingival defect, onlays of cast porcelain have the advantages of a high success rate, co Conclusion For posterior teeth with a subgingival defect, onlays of cast porcelain have the advantages of a high success rate, convenient clinical operation and no influence on periodontal health to restore posterior teeth after deep margin elevation.

Surface modification of titanium implants is a hot topic for improving osteointegration and includes physical, chemical, bioactive and anodization methods. Among these methods, anodization methods can form TiO2 nanotube structures with a uniform and stable structure, and TiO2 nanotubes and substrates have high binding strengths and osteogenic properties and represent an excellent method for implant modification. TiO2 nanotube osteogenesis is closely related to its morphology, diameter and physicochemical characteristics. Therefore, the structure of TiO2 nanotubes with optimal osteogenic performance can be prepared by regulating these factors. At present, research on TiO2 nanotubes is mostly focused on composite treatments with TiO2 nanotubes, namely, the combination of other implant modification methods (physical method, chemical method, biological method) and TiO2 nanotubes to form a composite structure to work synergistically to treat osteogenesis. TiO2 nanotube composite treatment is a good prospective application for the further preparation of TiO2 nanotube-modified structures with strong osteogenic properties.

The foreign body reaction refers to a chronic inflammatory reaction and a wound-healing reaction that mainly involve macrophages and foreign body giant cells, which occur after a biological material is implanted into the body. Since macrophages in the foreign body reaction are recruited to the surface of the material after implantation of the material, subsequent secretion of a series of inflammatory factors and fusion into foreign body giant cells may lead to the degradation of the biological materials and environmental stress cracking. Moreover, the prolongation of macrophage polarization and the influence of related receptors may also lead to the phenomenon of fiber encapsulation, resulting in poor prognosis. Some scholars are committed to reducing the response of foreign bodies from the perspective of macrophages and foreign body giant cells, specifically by regulating the secretion of related inflammatory factors, reducing the subtypes of M1 macrophages, promoting their polarization to M2 macrophages, and regulating the fusion of macrophages and selective expression of macrophage-associated receptors to regulate fibrosis. The new immunological view holds that macrophages have the potential to repair bone tissue via angioplasts and osteogenesis in foreign body reactions. Therefore, the gold standard that has long been considered in regenerative medicine, which is that an inert material does not cause a foreign body reaction, is expected to be gradually replaced by tissue engineering that regulates tissue activity and function.

Oral infectious diseases include caries, periodontal disease, halitosis, candidiasis albicans and so on. Over the past few decades, probiotics have mainly been studied in the field of the gastrointestinal tract. In recent years, probiotics have begun to be used in the prevention and treatment of various oral diseases and have become a new field in the research of oral disease prevention and control technology. This paper reviews the research progress of probiotics applied in the prevention and treatment of various oral infectious diseases. A review of the literature shows that probiotics can prevent and cure dental caries by inhibiting the growth of Streptococcus mutans and competing with them for nutrition and attachment sites. Probiotics not only inhibit periodontal pathogens and reduce the production of sulfide, they also regulate the body’s immune function to alleviate halitosis and periodontal inflammation. Probiotics can inhibit periodontal caries by inhibiting them. Probiotics can inhibit them mycelial growth of Candida albicans and interfere with its adherence, thus playing a role in the prevention and treatment of oral candidiasis. Current studies have shown that probiotics play an auxiliary role in the treatment of caries, periodontitis, halitosis and oral candidiasis. However, the mechanism of probiotics in the prevention and treatment of oral infectious diseases is still unclear, and the safety of probiotics remains to be further studied. In the future, oral probiotics should be studied with reference to intestinal probiotics to better work to prevent and treat oral diseases.