Relationship between maxillary posterior molar roots and the maxillary sinus floor: Cone-beam computed tomography analysis of a western Chinese population.

OBJECTIVE: This study aimed to assess the positional relationships between the maxillary sinus and the first and second molars in a western Chinese population by using cone-beam computed tomography. METHODS: This study included 212 patients (652 maxillary molars and 1956 roots). Patient demographics (sex and age) and cone-beam computed tomography data regarding the relationship between molar roots and the maxillary sinus were obtained. This relationship was stratified into four types for statistical analysis. RESULTS: Sex and side did not significantly influence the distance between maxillary molar roots and the maxillary sinus. However, the distance between maxillary molar roots and the maxillary sinus increased with age. The mesiobuccal root of the second molar was nearest to the maxillary sinus. The most common relationship type involved absence of root contact with the sinus border and presence of a maxillary sinus cross-section above the root apex. CONCLUSIONS: Compared with other teeth, the maxillary posterior teeth have a complex anatomical structure and are closely related to the sinus. These findings may serve as reference information for root canal treatment, tooth extraction, dental implant, and other dental clinical procedures among patients in western China.

Combined Use of Specially-Designed Digital Surgical Guides and Pre-Formed Reconstruction Plate to Treat Bilateral Mandibular Fracture.

This paper describes the application of a modified digital surgical guide, an occlusal template and a pre-formed reconstruction titanium plate in the open reduction and internal fixation of a bilateral mandibular fracture. Bilateral mandibular fracture is a commonly encountered simple type of fracture. However, even for an experience surgeon, achieving precise treatment remains a challenge due to the movable temporomandibular joint, unstable fractured segments, the difficulty in forming a reconstruction plate, and the lack of an effective stabilizing and locating device. In this case, the surgeon used a specially-designed modified guide together with a reconstruction plate and an occlusal template to treat a bilateral mandible fracture, effectively improving the accuracy and the medical outcome of the operation, saving operation time and reducing postoperative complications.

Corrigendum to "Clinical analysis of medication related osteonecrosis of the jaws: A growing severe complication in China" [J Dent Sci 13 (3) (September 2018) 190-197].

[This corrects the article DOI: 10.1016/j.jds.2017.12.003.].

Bioinformatic analysis of PFN2 dysregulation and its prognostic value in head and neck squamous carcinoma.

AIM: This study aimed to identify PFN2 expression profile, its prognostic value and the mechanism of its dysregulation in head and neck squamous cell carcinoma (HNSC). MATERIALS & METHODS: Bioinformatic analysis was performed using data in the Gene Expression Omnibus Datasets, Human Protein Atlas and The Cancer Genome Atlas-HNSC. RESULTS: PFN2 was upregulated in HNSC than in normal head and neck tissues. High PFN2 expression independently predicted poor overall survival in primary HNSC (hazard ratio: 1.548, 95% CI: 1.174-2.042; p = 0.002). Fourteen percent of HNSC cases had PFN2 amplification. PFN2 DNA methylation was negatively correlated with its mRNA expression (Pearson's r = -0.713). CONCLUSION: High PFN2 expression might serve as a valuable predictor for poor overall survival of HNSC. DNA amplification and hypomethylation might be two mechanisms of PFN2 dysregulation.

Clinical analysis of medication related osteonecrosis of the jaws: A growing severe complication in China.

BACKGROUND/PURPOSE: Medication-related osteonecrosis of the jaws (MRONJ) is an unusual but quite serious complication. However, its mechanism remains unclear, and its treatment protocol is still controversial. MATERIALS AND METHODS: Our study involved 201 osteonecrosis of the jaw (ONJ) patients from September 2006 to March 2017. We analyzed risk factors, clinical characteristics, treatment, etc., by comparing MRONJ with other ONJs. RESULTS: Among 201 patients, MRONJ accounted for 14.71% and it presented a consistent increase tendency. In comparison with other ONJs, we considered advanced age, maxilla lesion, diabetes mellitus, tooth extraction, especially multi-teeth extraction as risk factors (P < 0.0125). Our study demonstrated that maxillary lesion was associated with an advanced stage and it was inclined to worse prognoses. We also found MRONJ had little correlation to Actinomyces infection. Surgical treatment could improve patients' condition successfully (P > 0.05). 81.3% patients with advanced stage showed complete or partial healing lesions after surgery. CONCLUSION: Advanced age, maxilla lesion, diabetes mellitus, tooth extraction seem to be important triggering factors for MRONJ. Clinicians and surgeons should pay attention to maxillary lesions as it is related to severe symptoms and unfavorable prognosis. Once diagnosed as MRONJ, surgery is an effective treatment for patients with advanced stage.

Microwave Ablation: A Novel Treatment for the Mucoceles of Anterior Lingual Salivary Glands.

PURPOSE: The objective of this study was to evaluate the efficacy of microwave ablation as a substitute for surgery in patients with a mucocele of the anterior lingual salivary glands. MATERIALS AND METHODS: In the Department of Oral and Maxillofacial Surgery, Hospital of Stomatology, Sichuan University (Chengdu, China), 78 patients with a clinical diagnosis of a mucocele of the anterior lingual salivary glands underwent microwave ablation from November 2012 to May 2015. Outcome and data on age, gender, size of lesion, history of trauma, and duration of lesion development for each patient were collected. RESULTS: In this series, all patients fully recovered and only 5 patients received a second ablation. Wound healing was uneventful in all cases and a small scar was observed in only 6 patients. No serious complications were observed except for local discomfort in 2 cases and tongue tip numbness in 3 cases, but the problems resolved within several days without management. CONCLUSION: Microwave ablation is a safe, straightforward, less invasive, economic, and effective therapeutic method for a mucocele of the anterior lingual salivary glands and can be used as a primary treatment modality before considering surgery.

[Dentists should improve the ability to deal with medical emergencies in dental clinic].

In recent years, the number of outpatients in stomatological hospital is in increasing year by year and being accompanied by the corresponding medical risks. One of the risks which may endanger the patient life is medical emergency which need emergency treatment by the dentists in dental clinical practice. The most common emergency type is syncope, followed by hyperventilation, drug overdose, adrenaline reaction and hypertension, etc. Unexpected events mainly occurred at the end of the treatment and before leaving the dental clinic, during or immediately after the local anesthesia, in the treatment process. Tooth extraction related emergency is the most frequently occurring emergency, followed by the local anesthesia related ones. It's strongly suggested that dentists should pay more attention to outpatient clinical emergency treatment, and related knowledge and skills training should be offered to improve the ability to handle medical emergencies.

The management of naso-orbital-ethmoid (NOE) fractures.

The bony naso-orbital-ethmoid (NOE) complex is a 3-dimensional delicate anatomic structure. Damages to this region may result in severe facial dysfunction and malformation. The management and optimal surgical treatment strategies of NOE fractures remain controversial. For a patient with NOE trauma, doctors should perform comprehensive clinical examination and radiographic analysis to assess the type and extent of fracture. The results of assessment will assist doctors to make a patientspecific program for the sake of reducing post-operation complications and restoring normal appearance and function as much as possible. This review focuses on the advancement of management of NOE fractures including symptoms, classifications, diagnosis, approaches, treatment and new techniques in this field.

Mesenchymal stem cells systemically injected into femoral marrow of dogs home to mandibular defects to enhance new bone formation.

Musculoskeletal diseases cost the U.S. $849 billion annually. To date, there has been no proof that remote long bone mesenchymal stem cells (BMSC) can home to craniofacial defects for bone regeneration. There has been no report that systemic BMSC injection can increase new bone formation in large animals. The objectives of this study were to use a sex-mismatched canine model for systemic BMSC injection and homing to mandibular defects and to investigate appendicular BMSC migration to craniofacial defects to increase new bone formation. Male beagle dog BMSC were injected into the femoral marrow cavity of female dogs upon which mandibular defects were created. The dogs were sacrificed at 6 weeks. Cells with Y chromosome markers were detected in defects of female dogs with systemic male BMSC injection, indicating the homing of the transplanted BMSC from femoral marrow to the mandibular defect. New bone formation in dogs with systemic BMSC injection was 20-40% higher than control without BMSC injection (p<0.05). Mineralized new bone percentage was increased by 20-40% due to systemic BMSC injection (p<0.05). In conclusion, this study proved that (1) allogeneic BMSC injected into long bone marrow are capable of homing to both appendicular and craniofacial bone in large animals and (2) systemically injected BMSC can significantly increase new bone formation in dog's mandibular defects. These results may help advance the understanding of stem cell homing and present a therapy to enhance bone repair, which may have a wide applicability to the regenerative medicine field.

[Systematic review on control of swelling and trismus after extraction of impacted mandibular third molar by dexamethasone pericoronal injection].

OBJECTIVE: To assess the efficacy of Dexamethasone (DM) pericoronal injection for the control of swelling and trismus caused by impacted mandibular third molars extraction. METHODS: Cochrane, PUBMED, EMBASE and CBM were searched for eligible studies. Hand-searching included references of the included studies and Chinese dental journals. Risk of bias of the included studies was assessed by two reviewers independently using Cochrane Collaboration's tool, and data extraction was done by them. Meta-analysis was delivered with Revman 5.1. RESULTS: Seven randomized controlled trials, involving 684 participants, were included. Six of them had moderate risk of bias and one had high risk of bias. Meta-analysis showed that DM pericoronal injection could relieve trismus by 6.77 mm (P=0.02) within 1-2 days after the surgery. It could also reduce 51% of the risk of moderate-severe trismus(P<0.000 01) and could significantly control facial swelling (P<0.05). There was no differences between 4 mg and 8 mg DM (P>0.05). CONCLUSION: Periodontal injection of 4-5 mg DM could control facial swelling and trismus following impacted mandibular third molar extraction. But more randomized controlled trials are needed.

[Effects of different education methods on compliance and satisfaction of the patients with temporomandibular disorders].

OBJECTIVE: To compare the effects of video or leaflet in conjunction with traditional patient education (TPE) with traditional patient education alone for the compliance and satisfaction of the patients with temporomandibular disorders (TMD). METHODS: One hundred and thirty-three patients with TMD who needed intra-articular injection of hyaluronate were included and randomly divided into three groups: Group I accepted video education plus TPE, Group II accepted leaflet education plus TPE, Group III accepted TPE alone. All the participants were recorded by demographic characteristics (sex, age) before treatment, and their compliance, satisfaction and self-exercise were also recorded after one month followed-up. RESULTS: The baseline parameters (sex, age and diagnosis) of the groups were similar (P > 0.05). Seventeen participants lost in follow-up, including 4.5% in Group I, 11.1% in Group II and 22.7% in Group III. There were significant differences in lost rates among the three groups (P = 0.035). The rates of participants who exactly followed the appointed follow-up were higher in Group I and II than in group III (P = 0.04). And the satisfaction rates were 90.5% in Group I, 92.5% in Group II, 76.5% in Group III. The satisfaction rates of Group I and Group II were significantly higher than that of Group III (P = 0.05). The patients in Group I and Group II were more compliant with the self-exercise than that in Group III (P = 0.007). CONCLUSION: Adding video or leaflet education to the TPE could increase the patients' compliance, satisfaction and execution of the self-exercise.

Treatment of skin injury due to vinorelbine extravasation using bFGF and rhGM-CSF: an experimental study in a murine model.

BACKGROUND AND OBJECTIVE: A murine model of skin injury from vinorelbine extravasation was established to evaluate the treatment efficacy of basic fibroblast growth factor (bFGF) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). MATERIALS AND METHOD: Experimental models were divided into bFGF, rhGM-CSF, and control (saline) groups, with 40 mice in each group. Edema and ulceration were measured on Days 1, 3, 5, 7, 10, 14, and 18 after the onset of extravasation; injuries were examined pathomorphologically in three mice/group/time point. RESULTS: Edema reached maximum size on Day 3 in the bFGF and rhGM-CSF groups and Day 5 in the control group. The difference between the two experimental groups was not significant; differences between the control group and the experimental groups were statistically significant at all time points. Edema and ulceration began to improve on Day 10 in the bFGF and rhGM-CSF groups and Day 18 in the control group. Healing duration was 14-18 days in the experimental groups, with a (not significantly) shorter duration in the bFGF group. Healing was completed by Day 27.5 in the control group. Pathomorphological evaluation showed regular re-epithelization and newly formed granulation tissue in the bFGF and rhGM-CSF groups on Day 13. In the control group, wounds were partially healed, edema and shallow ulcers existed, and epithelization was fragile and disorganized on Day 18. CONCLUSIONS: bFGF and rhGM-CSF are useful for the treatment of skin injury due to vinorelbine extravasation, but bFGF may be slightly more effective in decreasing time and improving quality of healing.