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Background: Early detection of peri-implant bone defects can improve long-term durability of dental implants. By the advances in cone-beam computed tomography (CBCT) scanners and introduction of new algorithms, it is important to find the most efficient protocol for detection of bone defects. This study aimed to assess the efficacy of metal artifact reduction (MAR) and advanced noise reduction (ANR) algorithms for detection of peri-implant bone defects. Materials and methods: In this in vitro study, 40 titanium implants were placed in 7 sheep mandibles. Crestal, apical, and Full defects (n = 10 from each type) were created around the implants, and 10 implants were also placed as controls. CBCT scans were obtained in four modes: with MAR, with ANR, with both MAR and ANR, and without any filter. Totally, 28 scans were obtained and evaluated by a radiologist and a maxillofacial surgeon. The observers recorded their observations in a checklist, and data were analyzed by SPSS version 21 using the kappa coefficient of agreement, sensitivity and specificity values, area under the receiver operating characteristic (ROC) curve (AUC), intraclass correlation coefficient, t-test and paired t-test (P < 0.05). Results: The inter-observer agreement was high for detection of all defects in all modes except with ANR. No significant difference was found in AUC and diagnostic accuracy of different scan modes (P > 0.05). The most common diagnostic error was related to misdiagnosis of control group with full defect with ANR filter, such that the existing bone was not detected. Defect depth was averagely over-estimated while defect length was under-estimated. Correct diagnosis of defects had the highest frequency when both filters were on. Conclusion: The diagnostic accuracy and sensitivity for detection of different defect types were not significantly different in different scan modes but activation of ANR filter significantly decreased the specificity and positive predictive value compared with no use of filter. [ABSTRACT FROM AUTHOR]

Background: The oxidant/antioxidant balance is disrupted in anemia. Antioxidant capacity depends on antioxidant enzyme activity and some trace elements. This study aimed to evaluate oxidant/antioxidant status and its correlation with red blood cell indices and anemia severity in anemic patients. Methods: Blood samples were taken from 90 anemic patients and 95 healthy people. Circulatory miR-122 was assayed by real-time PCR. Malondialdehyde (MDA), pro-oxidant/antioxidant balance (PAB), supper oxide demitasse (SOD), glutathione peroxidase (GPxs) activity, total antioxidant capacity (TAC), and zinc were measured by colorimetric method. Selenium was also determined using atomic absorption. Results: Selenium and zinc decreased significantly in the case group (**P=0.004 and ***P=0.000). The amount of miR-122 up-regulated in the anemia (**P=0.003). MDA was significantly raised in the case vs control (***P=0.0002). PAB was higher in the case group (**P=0.005). SOD and GPxs activity was decreased along with TAC in anemic patients (*P=0.02, **P=0.008, *P=0.038). Zinc and PAB levels correlated with some red blood cell indices. PAB was associated with anemia severity. Conclusion: Increased PAB and decreased zinc/selenium increased oxidant levels in anemic patients. RBC indices and anemia severity were correlated with oxidant/antioxidant somewhere. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this systematic review is to compare cone-beam computed tomography (CBCT) and two-dimensional radiography in the assessment of facial asymmetry. Methods: Three valid electronic databases (PubMed, Scopus, and Web of Science) were searched for articles published from 1973 to February 2017. Hand searching was done through references of selected articles, internal thesis, and national and international conferences. The titles and abstracts obtained from the search were evaluated by reviewers according to the inclusion and exclusion criteria. Results: The established search strategy identified 2137 articles. A total of 2079 articles were from electronic search in three international databases and 58 articles from hand searching. After eliminating duplicate articles and on the basis of inclusion and exclusion criteria, 13 articles and 1 thesis entered the final analysis. Bayesian meta-analysis was done due to the heterogeneity of articles and the differences related to the methodology of the studies. According to this method, analyzing J-J landmark in two studies showed that there were no statistical differences between posteroanterior (PA) radiography and three-dimensional method with reference standard. Conclusion: The results of the study showed that there was no preference between the two techniques in measuring and diagnosing the landmarks and evaluating asymmetry. It can be concluded that in patients having problems other than asymmetry and need more information for the treatment plan, CBCT is more helpful than PA cephalometry. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess bone quality in patient's preoperative cone beam computed tomography (CBCT) and their relation with marginal bone loss at implant placement sites over follow-up periods. Materials and Methods: In this retrospective cross-sectional study, 100 implants were evaluated. The implants had been placed in the maxillary and mandibular edentulous areas. Bone quality at implant placement sites was measured on preoperative CBCTs and then classified by two observers according to Lekholm and Zarb classification. Marginal bone height was then measured on periapical radiographs obtained at baseline and then 6, 12, 18, 24, and 30 months' follow-up periods from a reference point (implant shoulder) to the bone-implant interface. The relation between bone quality and bone loss was assessed. ANOVA was used to compare mean difference among groups and Pearson correlation coefficient to assess the correlation between observers. All statistical analyses were performed at 0.05 significance level using Stata 11 software (StataCorp, College Station, TX, USA). Results: Of 100 implants, 48 were placed in the maxilla and 52 in the mandible. There was no significant difference between bone quality and the mean bone loss at follow-up periods. Using Pearson's correlation coefficient, it was shown that with an increase in bone quality, marginal bone loss was decreased at follow-up periods. Conclusions: The results confirmed that during the follow-up periods, less bone loss was observed in implant areas with higher bone quality and CBCT is a reliable tool for assessing bone quality at implant placement sites and estimation of subsequent treatment prognosis. [ABSTRACT FROM AUTHOR]