Objective:To explore the clinical efficacy of stomatognathic system functional exercise (SSFE) in the treatment of temporomandibular joint osteoarthritis (TMJOA), and to provide reference for the clinical treatment of TMJOA.Methods:Choose between January 2020 and June 2020 in the Affiliated Hospital of Qingdao University of Temporomandibular Disorders (TMD) Clinics, pain in the temporomandibular joint (TMJ), limited openings for complained of symptoms of TMD patients, diagnosed by clinical examination and cone-beam CT (CBCT) examination of TMJOA patients (60 cases, 64 joints), including 20 males and 45 females, the age was (42.6±2.5) years (33-47 years old). The patients were randomly divided into the experimental group (30 cases, 34 joints) and the control group (30 cases, 30 joints) according to the odd and even numbers of their treatment numbers. The experimental group was treated with SSFE method. The control group was treated with maxillary full dentition occlusal splint. Visual analogue score (VAS), natural mouth opening and maximal mouth opening (MMO) of each patient in each group were recorded at initial diagnosis, 2 weeks, 3 and 6 months after treatment, and CBCT imaging was compared for the changes of condylar bone at initial diagnosis, 3 and 6 months after treatment.Results:VAS values of the experimental groups were (2.90±1.42), (0.90±0.37), (0.87±0.23) at 2 weeks, 3 and 6 months after treatment, respectively. The VAS values of the control group were (4.57±1.94), (4.17±2.09), (3.73±2.21), respectively. The VAS score of the experimental group was significantly lower than that of the control group ( F=42.93, P<0.001). Before SSFE treatment, all the patients in the experimental group had different degrees of restricted opening and characteristic abnormal opening and closing pattern. Two weeks after SSFE treatment, the opening degree of the patients was (38.69±6.40) mm, the opening shape "↓" and the closing shape "↑" were normal. At 3 and 6 months after treatment, the opening degree were (41.98±5.08) and (43.73±3.76) mm, respectively. The opening degree of control group was (36.85±6.33) mm 2 weeks after treatment, and the characteristic abnormal opening and closing pattern still existed. The opening degree of control group were (37.82±5.85) and (38.40±5.75) mm at 3 and 6 months after treatment, respectively. The characteristic abnormal opening and closing pattern (stuffy, awkward, deliberate, unnatural) did not improve significantly. The openness of the experimental group was significantly higher than that of the control group ( F=25.20, P<0.001). In the experimental group, 82.4% (28/34) had benign remodeling of condylar bone 6 months after treatment, and 17.6% (6/34) had no change of condylar bone. There was no significant change in condylar bone in control group. The CBCT scores in the experimental group [(2.43±1.74) and (1.70±1.26)] were significantly lower than in the control group [(4.23±1.50) and (4.10±1.37)] at 3 and 6 months after treatment ( F=27.20, P<0.001). Conclusions:Full dentition occlusal splint can alleviate the pain in the joint area of TMJOA patients, but can not improve the characteristic abnormal mandibular movement, and the condyle bone repair is not obvious. SSFE can effectively relieve the symptoms and signs of TMJOA patients, especially improve the abnormal characteristic mandibular movement, and promote the normal reconstruction and repair of condylar bone.

Objective: To investigate the effects of different concentrations of MgSiF₆ as electrolyte on the bond strength between titanium and porcelain after micro-arc oxidation (MAO) treatment and screen the suitable concentration of MgSiF₆ that can improve the bond strength between titanium and porcelain. Methods: Four different concentrations of MgSiF₆ (10, 20, 30, 40 g/L) were chosen as MAO reaction solutions. Sandblasting treatment was selected as a control group. After porcelain was fused to each specimen, titanium-porcelain bond strengths were evaluated by the three-point bending test according to ISO 9693. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were adopted to evaluate the morphologies and elemental compositions of both the MAO coatings and the interfaces of the titanium-porcelain restoration. Results: The surface of titanium specimen in the control group was sharp and rough, while specimens in both 10 g/L group and 20 g/L group were porous and homogeneous. However, the pores found on the specimens in the latter group were larger in diameter (approximately 1.0-2.0 μm) than those on the former one (0.2-0.5 μm). The bond strengths of the control group and the experimental groups (10, 20, 30, 40 g/L MgSiF₆) were (27.08±3.16), (38.18±2.65), (44.75±2.21), (36.44±2.04), (31.04±2.59) MPa, respectively. All the experimental groups showed higher bond strengths than the control group did (P<0.05), and the bond strength of 20 g/L MgSiF₆ group was significantly higher than those of the other groups (P<0.05). Besides, the interfaces between titanium and porcelain were tight and compact in the 20 g/L group, while different amounts of pores and cracks were visible in the other groups. Additionally, after the three-point bending test, few residual porcelains could be observed on the surfaces of specimens in the control group. Conclusions MAO treatment with 20 g/L MgSiF₆ on titanium can improve bonding strength between titanium and porcelain.