Naichuan Su

Ultrasonography for detection of disc displacement of temporomandibular joint: a systematic review and meta-analysis

PURPOSE To assess the diagnostic efficacy of ultrasonography in detecting disc displacement of the temporomandibular joint. MATERIALS AND METHODS MEDLINE (using OVID, 1950 to April 2011), EMBASE (1980 to April 2011), and the Chinese Biomedical Literature Database (1978 to April 2011) were searched electronically. In addition, relevant journals and reference lists of the included studies were manually searched for any eligible studies on diagnostic accuracy. Two authors performed the study inclusion, data extraction, and risk of bias assessment in duplicate. Meta-analysis was performed with MetaDisc 1.4. RESULTS Fifteen studies were included in this meta-analysis; 6 studies had a low risk of bias, 6 studies an unclear risk, and 3 studies a high risk. Meta-regression indicated that the detected results were not influenced by the types of ultrasonography, image dimensions, types of transducer, and ultrasonic image of the disc (P > .05). The Q* values of ultrasonography for the closed- and open-mouth positions were 0.79 and 0.91, respectively. The diagnostic efficacy of disc displacement with reduction had a sensitivity of 0.76, a specificity of 0.82, a positive likelihood ratio of 3.80, a negative likelihood ratio of 0.36, a diagnostic odds ratio of 10.95, an area under the curve of 0.83, and a Q* of 0.76. The diagnostic efficacy of disc displacement without reduction had a sensitivity of 0.79, a specificity of 0.91, a positive likelihood ratio of 80.5, a negative likelihood ratio of 0.25, diagnostic odds ratio of 36.80, an area under the curve of 0.97, and a Q* of 0.92. CONCLUSIONS The diagnostic efficacy of ultrasonography is acceptable and can be used as a rapid preliminary diagnostic method to exclude some clinical suspicions. However, positive ultrasonographic findings should be confirmed by magnetic resonance imaging. Also, the ability of ultrasonography to detect lateral and posterior displacements is still unclear. More high-quality studies are needed to assess the diagnostic efficacies of some specific ultrasonographic methods. Standards and criteria for ultrasonographic techniques in the diagnosis of disc displacement should be established in the future.

Effects of self-ligating brackets on oral hygiene and discomfort: a systematic review and meta-analysis of randomized controlled clinical trials.

Background: Self‐ligating brackets (SLBs) are widely adopted in clinic owing to their claimed superiorities. Here, we collected and analysed all randomized controlled clinical trials (RCTs) comparing SLBs with conventional brackets (CBs) and thereby investigated whether SLBs can relieve discomfort or promote oral hygiene. Methods: Electronic databases including MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, Chinese BioMedical Literature Database and the China National Knowledge Infrastructure were searched to find out RCTs comparing active or passive SLBs with CBs. Two reviewers extracted the data and assessed risks of bias independently. Any disagreement between them was resolved through discussion with a third reviewer. Meta‐analysis was conducted on Review Manager 5.3. Results: A total of 12 RCTs with 575 participants were included, and eight of the trials were synthesized quantitatively. Two trials were assessed as low risk of bias, whereas others as unclear risk of bias. Passive SLBs and CBs are not significantly different in plaque control. SLBs and CBs are not significantly different in discomfort reduction at any of four time points (4 h, 24 h, 3 days and 7 days). Conclusions: Clinical evidences from existing RCTs suggest that SLBs do not outperform CBs in reliving discomfort or promoting oral health in clinic.

Effects of core-to-dentin thickness ratio on the biaxial flexural strength, reliability, and fracture mode of bilayered materials of zirconia core (Y-TZP) and veneer indirect composite resins

Statement of problem. Indirect composite resins (ICR) are promising alternatives as veneering materials for zirconia frameworks. The effects of core‐to‐dentin thickness ratio (C/Dtr) on the mechanical property of bilayered veneer ICR/yttria‐tetragonal zirconia polycrystalline (Y‐TZP) core disks have not been previously studied. Purpose. The purpose of this in vitro study was to assess the effects of C/Dtr on the biaxial flexural strength, reliability, and fracture mode of bilayered veneer ICR/ Y‐TZP core disks. Material and methods. A total of 180 bilayered 0.6‐mm‐thick composite resin disks in core material and C/Dtr of 2:1, 1:1, and 1:2 were tested with either core material placed up or placed down for piston‐on‐3‐ball biaxial flexural strength. The mean biaxial flexural strength, Weibull modulus, and fracture mode were measured to evaluate the variation trend of the biaxial flexural strength, reliability, and fracture mode of the bilayered disks with various C/Dtr. One‐way analysis of variance (ANOVA) and chi‐square tests were used to evaluate the variation tendency of fracture mode with the C/Dtr or material placed down during testing (&agr;=.05). Light microscopy was used to identify the fracture mode. Results. The mean biaxial flexural strength and reliability improved with the increase in C/Dtr when specimens were tested with the core material either up and down, and depended on the materials that were placed down during testing. The rates of delamination, Hertzian cone cracks, subcritical radial cracks, and number of fracture fragments partially depended on the C/Dtr and the materials that were placed down during testing. Conclusion. The biaxial flexural strength, reliability, and fracture mode in bilayered structures of Y‐TZP core and veneer ICR depend on both the C/Dtr and the material that was placed down during testing.

Performance of different imaging techniques in the diagnosis of head and neck cancer mandibular invasion: A systematic review and meta-analysis

BACKGROUND To assess diagnostic efficacy of imaging techniques for mandibular invasion by head and neck cancer. METHODS Thirteen databases were searched. Study inclusion, data-extraction and quality assessment were performed independently. STATA 14.0 were mainly used for meta-analysis. RESULTS Forty-nine studies were included. For mandibular invasion (cortex and marrow), CBCT, SPECT, CT, MRI, orthopantomography, PET-CT and bone-scintigraphy showed pooled sensitivities of 90%, 97%, 73%, 88%, 75%, 90%, 92%, specificities of 85%, 69% 91%, 90%, 83%, 89%, 79%, AUC of 0.9461, 0.9434, 0.8995, 0.9296, 0.8761, 0.9290, 0.9207, respectively. The combined SROC curves indicated CBCT and SPECT were superior to other techniques. For mandibular medullary invasion (marrow), CT and MRI showed pooled sensitivities of 85% and 93%, specificities of 86% and 84%. CONCLUSIONS CBCT was top-priority choice for bone invasion diagnosis. SPECT was recommended for exclusion, CT and MRI were suitable for conformation. Further investigations are needed for mandibular medullary involvement.

Correlation between oral health-related quality of life and clinical dysfunction index in patients with temporomandibular joint osteoarthritis.

We evaluated the correlation between oral health-related quality of life (OHRQoL) and the Helkimo clinical dysfunction index (HDI) in patients with temporomandibular joint osteoarthritis (TMJ OA). Clinical data and scores for the Chinese version of the 14-item Oral Health Impact Profile (OHIP-C14) were recorded and analyzed for 541 patients with TMJ OA. Each patient was assigned an HDI score of 1 to 25, which was used to classify severity into three categories. OHRQoL was assessed by using OHIP-C14 score, which ranged from 0 to 56. Both HDI score and severity were significantly correlated with total OHIP-C14 score (P < 0.001 for both comparisons). The scores for all HDI domains except function impairment (P = 0.205) were significantly correlated with OHIP-C14 score. The scores for all seven OHIP-C14 domains were significantly correlated with HDI score and severity. Several correlations between OHIP-C14 domains and HDI domain scores were significant. HDI score and severity were correlated with OHIP-C14 score in TMJ OA patients. As compared with function-related domains, pain-related HDI domains were more strongly inversely related to OHRQoL.(J Oral Sci 58, 483-490, 2016).