Search

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]

Introduction: Cervical cancer represents one of the main causes of female, cancer-related mortality worldwide. The majority of cancers are caused by human papillomaviruses such as HPV16 and HPV18. As chemotherapeutic resistance to first-line platinum treatment is still a predominant clinical challenge in advanced cervical cancer, novel treatment options including combinatorial therapies are urgently required to overcome chemotherapeutic resistance. Inhibition of A Disintegrin And Metalloproteinase (ADAM)-family members, heavily involved in tumour progression of a vast range of solid tumours, strongly improved response to chemotherapeutic treatment in other tumour entities including ovarian cancer. Methods: We established two- and three-dimensional models derived from three traditional cervical cancer cell lines and ectocervical cancer-derived organoids. Following characterisation, these models were used to investigate their response to cisplatin treatment in the absence and presence of ADAM inhibitors using viability assays and automated live cell imaging. Results: The pivotal role of the metalloprotease ADAM17 driving chemotherapy resistance was detectable in all ectocervical cultures irrespective of the model system used, whereas ADAM10 inhibition was predominantly effective only in loosely aggregated spheroids. We showed prominent differences regarding treatment responses between 2D monolayers compared to 3D spheroid and 3D organoid model systems. Particularly, the organoid system, regarded as the closest representation of primary tumours, exhibited reliably the combinatorial effect of ADAM17 inhibition and cisplatin in all three individual donors. Discussion: As two- and three-dimensional models of the same cell lines differ in their responses to chemotherapy it is essential to validate treatment strategies in more advanced model systems representing the patient situation more realistically. Ectocervical organoids showed reliable results regarding treatment responses closely mimicking the primary tumours and could therefore serve as an important tool for personalized medicine in cervical cancer. These findings strengthen the role of ADAM17 as a potential novel target for combinatorial treatments to overcome chemoresistance in cervical cancer. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The prevalence of different root canal morphologies and types of endodontic procedural errors has been previously evaluated. OBJECTIVES: This study aimed to assess the quality of endodontic treatments and most common procedural errors as well as to evaluate the correlation of procedural errors with the root canal morphology of premolar and molar teeth according to Vertucci's classification using cone-beam computed tomography (CBCT). Material and methods: In this cross-sectional study, 230 endodontically treated teeth were evaluated on 287 CBCT of patients presenting Hamadan Dental School from 2019 to 2021. Canal type was determined according to Vertucci's classification system. Endodontic procedural errors, including under-filling, over-filling, nonhomogenous filling, perforation, and missed canals were also assessed. Correlation between the type of procedural error and root canal morphology was analyzed with chi-square test using SPSS version 23, at 5% level of significance. RESULTS: Under-filling was the most common procedural error in Vertucci's type I canals (27.69%, p = 0.92). In types II and IV canals, the most common procedural error was missed canals, with a prevalence rate of 18.36% and 13.63%, respectively. Non-homogenous filling (p = 0.68) and missed canals (p = 0.003) were the most common errors in type III canals (25%). Over-filling (p = 0.05) and non-homogenous (p = 0.68) filling were the most frequent errors in type V canals (28.58%). CONCLUSIONS: Over-filling and missed canals showed a significant correlation with canal type. Moreover, the type of canal demonstrated a significant correlation with the presence of periapical lesions, i.e., periapical lesions showed the highest prevalence in canal types III and V. [ABSTRACT FROM AUTHOR]

Aim and Background: Due to the relatively high prevalence of binocular vision anomalies, a regular examination including tests for assessment and determination of these anomalies is necessary. The aim of this study was to assess the relationship between near point of convergence (NPC) and near binocular vision symptoms and finding of an NPC cutoff point for symptoms in university students. Materials and Methods: In this cross-sectional study, 124 students of different majors of Zahedan University of Medical Sciences were randomly selected. If they met the inclusion criteria, they were divided into two groups (symptomatic and asymptomatic) according to the convergence insufficiency symptom survey questionnaire. For NPC measurement, a small isolated letter "E" of approximately 20/30 size on a metal rod was used. After data collection, data were analyzed in SPSS.17 software (SPSS for Windows, SPSS Inc., Chicago, IL) using descriptive and analytical statistics, including Mann-Whitney U test and receiver operating characteristic (ROC) curve. Results: The mean NPC findings in the symptomatic and asymptomatic groups were 11.7 ± 5.0 and 8.4 ± 3.4 cm, respectively, with a significant difference between the two groups (P < 0.001). The ROC curve suggests an NPC cutoff point of 9.5 cm for the presence of symptoms with the testing procedures used in this study. Conclusion : The determination of NPC is helpful in the differentiation of symptomatic from asymptomatic subjects.

There is a special focus on using natural materials and herbal plants to prevent dental caries. Previous studies showed that some herbal plants have antimicrobial effects on oral pathogens. Thus we investigated the antimicrobial effects of three herbal extracts (Carum copticum, Phlomis bruguieri, and Marrubium parviflorum) on the growth of Streptococcus mutans, as the most important bacteria causing dental caries. First, plant methanolic extracts were prepared. Then, to evaluate the antimicrobial activity of the three herbal extracts, the agar well diffusion method and MIC were performed. The biofilm formation was carried out using a broth dilution method with 2% glucose-supplemented BHIS in sterile 96-well microplates. Serial dilutions (50, 25, 12.5, 6.25, 3.12 mg/ml) of extracts were prepared. Next, a 0.5 McFarland Suspension of S. mutans was added to wells. The inhibitory effect on biofilm formation was measured by the ELISA reader apparatus. The assay was repeated three times, and the average was calculated as 3. The results were compared with those of Chlorhexidine 0.2%. Carum copticum showed a better effect in the agar well diffusion method than others. MIC of the extracts of Carum coptimum, Phlomis bruguieri, and Marrubium parviflorum were 3.12, 6.25, and 12.5 mg/ml, respectively. Overall, the highest activity belonged to Carum copticum extract. For the anti-biofilm effect, the OD values of Carum copticum and Marrubium parviflorum were significantly different from that of Phlomis bruguieri. Although all of the methanolic herbal extracts can inhibit S. mutans growth and remove the biofilm, the effect of Carum copticum was better than Phlomis bruguieri and Marrubium parviflorum. Further studies are recommended to indicate how these extracts perform against the bacteria. [ABSTRACT FROM AUTHOR]

Introduction: One factor in the evaluation of binocular vision is the measurement of stereopsis. Several methods are available for this purpose. The most common procedures are anaglyphic (with use of red-green filters) and vectographic (with use of polarized filters) procedures. The purpose of this study is the determination of stereopsis with local (Titmus) and global (TNO) tests in symptomatic and asymptomatic subjects with respect to type of disparity (crossed and/or uncrossed) in exophoric and esophoric subjects. Methods: In this cross-sectional study, 174 randomly selected students of Zahedan University of Medical Sciences served as subjects. Subjects were divided into symptomatic and asymptomatic groups according to the presence or absence of binocular vision symptoms. Dissociated heterophoria was determined with use of the alternate prism cover test and stereopsis with the TNO and Titmus tests. Results: The mean stereopsis with the TNO test in symptomatic and asymptomatic subjects with crossed disparity presentation of the stereo test was 133.1 ± 68.6 and 76.7 ± 81.9 sec arc, respectively. The stereopsis with the TNO test in symptomatic and asymptomatic subjects with uncrossed disparity presentation of the stereo test was 135.0 ± 66.0 and 83.2 ± 49.3 sec arc, respectively. With the Titmus test, the mean stereopsis with crossed disparity presentation of the stereo test in symptomatic and asymptomatic subjects was 44.3 ± 7.1 and 40.7 ± 3.3 sec arc, respectively, and with uncrossed disparity presentation of the stereo test 50.0 ± 11.8 and 40.0 ± 0.0 sec arc, respectively. The Mann- Whitney U test showed a statistically significant difference in stereopsis (with both presentations of the test) between the two groups (p<0.05). The difference in stereopsis between esophoric and exophoric subjects was between 30-60 arc seconds for global stereopsis, and less than 2 arc seconds for local stereopsis. Esophoric subjects generally had a higher threshold for symptoms. However, these differences were not statistically significant (p>0.05). The best cutoff points for distinguishing between symptomatic and asymptomatic subjects with the TNO and Titmus stereo tests were determined to be 90 and 45 seconds of arc, respectively. Conclusion: Stereopsis is a useful factor in distinguishing between symptomatic and asymptomatic individuals. For that purpose, a global test was more useful than a local test. Specifically, symptomatic subjects could be detected at a higher (90 arc sec) threshold with random-dot stereopsis than the 45 arc sec symptom threshold with Titmus-type stereopsis. Half of esophoric patients and only approximately a quarter of exophoric patients were symptomatic. [ABSTRACT FROM AUTHOR]