Nergiz Yılmaz

Diagnostic Value of Ultrasonography in Temporomandibular Disorders

PURPOSE The purpose of this study was to determine the diagnostic value of ultrasonographic imaging (USI) in temporomandibular disorders. PATIENTS AND METHODS USI and magnetic resonance imaging (MRI) were performed in 182 temporomandibular joints (TMJs) of 91 patients who were referred for treatment. After a detailed clinical examination, patients who were clinically diagnosed with TMJ disc derangement were referred to the radiology department for MRI and USI examinations. USI and MRI diagnoses of disc displacement were compared, using clinical diagnosis as the golden standard. The overall agreement between USI and MRI results was evaluated. RESULTS Compared with the clinical diagnosis, MRI showed a sensitivity of 85%, specificity of 62%, and an accuracy of 80% in the detection of internal derangements. The positive predictable value, negative predictive value, and likelihood ratio were 88%, 54%, and 2.29, respectively. Compared with the clinical diagnosis, USI showed a sensitivity of 69%, specificity of 80%, and accuracy of 71% in the detection of internal derangements. The positive predictable value, negative predictive value, and likelihood ratio were 92%, 42%, and 3.45, respectively. Comparing the agreements between the MRI and USI diagnoses of internal derangement, the κ value was found to be 0.36, indicating poor reliability (P < .001). CONCLUSION USI, a noninvasive and dynamic imaging method, is a reliable method in evaluating the position of the disc in TMJ disc derangements. Better visualization of joint structures and more reliable results with higher sensitivity and accuracy can be achieved with high-resolution devices (≥12 MHz).

Effect of antioxidant treatment on the shear bond strength of composite resin to bleached enamel

Abstract Introduction. This study examined the antioxidant treatment on the shear bond strength of composite resin to enamel after bleaching with two different bleaching systems. Materials and methods. Seventy flat enamel surfaces were prepared from freshly extracted human molars using a low speed diamond saw. Then the specimens were divided into seven random groups (n = 10) to apply different procedures; namely, bleaching with White Smile and bonding with composite resin (G1), bleaching with White Smile, treatment with ascorbic acid and bonding with composite resin (G2), bleaching with White Smile, immersing in artificial saliva for 2 weeks and bonding with composite resin (G3), bleaching with Opalesence and bonding with composite resin (G4), bleaching with Opalesence, treatment with ascorbic acid and bonding with composite resin (G5) and bleaching with Opalesence, immersing in artificial saliva for 2 weeks and bonding with composite resin (G6). Another group was used as a control group. Shear bond test was performed on all specimens and data were analyzed using one way ANOVA and Bonferronis test (p < 0.05). Results. Bond strengths of bleached specimens were significantly lower than those of non-bleached specimens. No statistical difference was found in bond strength between the bleached and non-bleached groups when the antioxidant treatment was carried out. Conclusion. Ten per cent ascorbic acid treatment was found to be an effective method to reverse the compromised bond strength.

Ultrasound assessment of increased capsular width in temporomandibular joint internal derangements: relationship with joint pain and magnetic resonance grading of joint effusion

OBJECTIVE The relationship between radiologic evidence of effusion in the temporomandibular joint (TMJ) and the occurrence of clinical symptoms (e.g., pain) is still unclear. Increased capsular width (CW) measured in ultrasonographic imaging (USI) of the TMJ was considered to be an indirect marker of TMJ effusion. The purpose of this study was to evaluate the relationship between the grades of magnetic resonance imaging (MRI)-depicted joint effusion (JE), increased CW measured in USI, and joint pain in TMJ internal derangement (ID) patients. STUDY DESIGN During a 4-year period, 91 patients clinically diagnosed with TMJ ID according to the Research Diagnostic Criteria for Temporomandibular Disorders classification were included in the study. Those with mainly myogenic complaints were excluded. In clinical examination, the severity of pain was assessed by visual analog scale (VAS, 0 to 10). All TMJs (n = 182) were evaluated to detect the presence of joint effusion by means of USI and MRI. MRI-depicted effusion was classified as no effusion, moderate effusion, and severe effusion. Receiver operating characteristic curve analysis was performed to depict the critical cutoff value for TMJ CW. USI sensitivity was evaluated by means of MRI effusion, and a cutoff value was depicted that was considered to be the threshold to discriminate the TMJs with and without effusion. The relationship between the joint pain and USI and MRI findings of effusion were evaluated with Friedman and Wilcoxon tests. RESULTS The average VAS scores of the TMJs without effusion was found to be 2.55, with moderate effusion 2.92, and with severe effusion 4.80. A significant positive correlation was found between the VAS scores and the intensity of MRI JE (P = .003). The most accurate cutoff value of CW is found to be 1.65 mm. The average VAS score with CW <1.65 was found to be 2.10 and the average VAS score with CW >1.65 was found to be 3.75. A significant positive correlation was found between the clinical pain scores and CW measured in USI (P = .001). CONCLUSIONS Both MRI-depicted effusion and USI assessment of CW were found to be related to the pain in TMJ ID patients.

Effect of osteoblast cell culture on the bone implant contact.

Abstract Purpose. The aim of this study is to acquire an ideal bone implant contact under the cover of osteogenic effect of osteoblasts derived from Mesenchymal Stem Cells (MSCs). Materials and methods. Thirty dental implants were used for this study. Implants were placed in sheep mandibles and defects were created 4 mm coronally in the dental implants. These defects were filled with Platelet Rich Plasma (PRP) in one group and with PRP + Osteoblast Cell Culture (OCC) in another group. No procedure was conducted on the control group defects (empty defect group). Eight weeks later, osseointegration was investigated with Bone Implant Contact (BIC) measurements histomorphologically. Data were checked statistically. Results. The variation of BIC rates between Empty Defect Group and PRP groups was significant (p <0.05). The BIC rate of the PRP group was higher than that of the Empty Defect Group. The variation of BIC rates between Empty Defect Group and PRP + OCC groups was significant (p <0.05). The BIC rate of the PRP + OCC group was higher than that of the Empty Defect Group. The variation of BIC rates between PRP and PRP + MSC groups was significant (p<0.05). The BIC rate of the PRP + OCC group was higher than that of the PRP group. At the end of the 8-week healing period, it was observed that the percentage of BIC was highest in the PRP + OCC group. Conclusions. Implant–bone connection was better in the OCC−PRP group compared with the PRP group and the empty defect group. The use of OCC-PRP combination was effective on healing. The BIC value was increased significantly by OCC.

Effect of surface treatments on implant crown retention

Background/purpose There are several surface treatment methods to improve the bond strength between dental materials. The purpose of this study was to examine the effect of different surface treatments on the tensile bond strength of single crowns on Implant Direct abutments cemented with resin cement. Materials and methods In total, 28 Screw Plant implants and abutments were divided into four study groups: I, control; II, sandblasted abutment and crown; III, non-sandblasted abutment and alloy primer applied to a sandblasted crown; and I V, alloy primer applied to a sandblasted abutment and crown. Twenty-eight crowns were cemented to abutments of implants, and a uniaxial tensile force was applied to the crowns using a universal test machine until cement failure occurred. Retention values were statistically analyzed. Results All mean retention values significantly differed among groups. While the alloy primer applied to the sandblasted castings and abutments showed the highest mean value (564.73 ± 13.66 N), the control group showed the lowest mean value (357.65 ± 12.89 N). Sandblasting was not as effective as application of an alloy primer (P = 0.05). Conclusion Sandblasting is an effective method to increase the bond strength. Sandblasting plus alloy primer application is a very effective method of increasing the bond strength, and these groups significantly differed from each other.