Pattern of Endodontic Periapical Lesion Extension in Anterior Teeth: A CBCT Study in an Iranian Population

Introduction: Health of periapical tissues has been considered as an index for the evaluation of endodontic outcomes. The present study sought to assess the pattern of periapical lesion extension in anterior teeth using cone-beam computed tomography (CBCT). Methods and Materials: In this descriptive study‚ 199 CBCT images belonged to patients aging from 15 to 79 were assessed according to periapical lesion extension in the regions of maxillary and mandibular anterior teeth. Maximum periapical lesion extensions in three orthogonal planes were measured and recorded in millimeters and were assessed according to age‚ gender‚ dental arch and tooth type. Statistical analysis was performed using percentages‚ repeated measure ANOVA and Bonferroni tests. The significant level was set at 0.05. Results: The highest average of lesion extension, in both maxilla and mandible, was in vertical dimension‚ followed by horizontal buccolingual and horizontal mesiodistal dimensions‚ respectively. There were significant differences between the vertical and mesiodistal (P=0.004) and also mesiodistal and buccolingual (P=0.010) periapical lesion extension dimensions. In addition, there were significant differences in maxilla and mandible (P=0.012). In maxilla, there were no significant differences between the three tooth types (P=0.346) but in the mandibular arch, there were significant differences between central-canine (P=0.004) and lateral-canine (P=0.026). According to independent variables, only gender had a significant effect on the lesion extension in anterior regions of maxilla and mandible (P=0.001). The periapical lesion extensions were significantly higher in men compared with women. Conclusions: The bone destruction_as a consequence of periapical inflammatory process_ was greatest in the vertical, and lowest in the horizontal mesiodistal dimensions. That way, the extension in buccolingual dimension, which could not be detected in the 2-D imaging techniques, was rather high in the present study. Thus CBCT, as a 3-D imaging technique, could be recommended for the precise evaluation of lesion extension in the periapical area.Keywords: Cone-beam Computed Tomography; Diagnosis; Endodontics; Periapical Disease; Periapical Lesion; Periapical Periodontiti

Effect of Metal Artifacts on Detection of Vertical Root Fractures Using Two Cone Beam Computed Tomography Systems

Introduction: Vertical root fracture (VRF) is common in endodontically treated teeth. Conventional and digital radiographies have limitations for detection of VRFs. Cone-beam computed tomography (CBCT) offers greater detection accuracy of VRFs in comparison with conventional radiography. This study compared the effects of metal artifacts on detection of VRFs by using two CBCT systems. Methods and Materials: Eighty extracted premolars were selected and sectioned at the level of the cemento-enamel junction (CEJ). After preparation, root canals were filled with gutta-percha. Subsequently, two thirds of the root fillings were removed for post space preparation and a custom-made post was cemented into each canal. The teeth were randomly divided into two groups (n=40). In the test group, root fracture was created with Instron universal testing machine. The control teeth remained intact. CBCT scans of all teeth were obtained with either New Tom VGI or Soredex Scanora 3D. Three observers analyzed the images for detection of VRF. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for VRF detection and percentage of probable cases were calculated for each imaging system and compared using non-parametric tests considering the non-normal distribution of data. The inter-observer reproducibility was calculated using the weighted kappa coefficient. Results: There were no statistically significant differences in sensitivity, specificity, PPV and NPV between the two CBCT systems. Conclusion: The effect of metal artifacts on VRF detection was not significantly different between the two CBCT systems.Keywords: Cast Post; CBCT; Cone-Beam Computed Tomography; Vertical Root Fractur

DETERMINATION OF ABSORBED DOSES FROM VARIOUS RADIOGRAPHICS TECHNIQUES REQUIRED FOR DENTAL IMPLANTS

The diagnostic and treatment benefits of various radiographic techniques, including those used routinely for dental implants, need to be evaluated against the complications and exposure risks involved. The aims of this study were to measure the amount of ionizing radiation absorbed by various critical tissues of the body in order to determine the risks of a radiographic procedure and to compare the amount of radiation absorbed by various tissues during radiographic procedures for dental implants. This in vitro study was performed on a humanlike X-ray phantom head using lithium thermo-luminescent dosimeters. The amount of radiation absorbed by critical tissues was more during the generation of a CT scan as compared to the use of linear tomography. The absorbed dose using these two techniques was more than when panoramic radiography was used. Organs defined as critical in this study were the eyes, thyroid glands, salivary glands, brain, bone marrow and skin. The amount of radiation absorbed by the thyroid gland during a mandibular CT scan was relatively high and therefore the use of a protective collar is recommended. The amount of radiation absorption in the parotid glands was more than the other two major salivary glands and also more than all other critical organs during a mandibular CT scan, an anterior and posterior linear tomographic survey or while taking a panoramic radiograph. The maximum amount of absorption in the parotid gland was in the maxilla CT, insignificant in relation to 10 grays, the dose resulting in acute inflammation of the gland. The maximum amount of radiation absorbed in the skin was during a mandibular CT scan which was lower than the dose resulting in erythema. The maximum amount of radiation absorbed was in during a mandibular CT scan

Development and multi-cohort validation of a clinical score for predicting type 2 diabetes mellitus.

BACKGROUND AND AIMS: Many countries lack resources to identify patients at risk of developing Type 2 diabetes mellitus (diabetes). We aimed to develop and validate a diabetes risk score based on easily accessible clinical data. METHODS: Prospective study including 5277 participants (55.0% women, 51.8±10.5 years) free of diabetes at baseline. Comparison with two other published diabetes risk scores (Balkau and Kahn clinical, respectively 5 and 8 variables) and validation on three cohorts (Europe, Iran and Mexico) was performed. RESULTS: After a mean follow-up of 10.9 years, 405 participants (7.7%) developed diabetes. Our score was based on age, gender, waist circumference, diabetes family history, hypertension and physical activity. The area under the curve (AUC) was 0.772 for our score, vs. 0.748 (p<0.001) and 0.774 (p = 0.668) for the other two. Using a 13-point threshold, sensitivity, specificity, positive and negative predictive values (95% CI) of our score were 60.5 (55.5-65.3), 77.1 (75.8-78.2), 18.0 (16.0-20.1) and 95.9 (95.2-96.5) percent, respectively. Our score performed equally well or better than the other two in the Iranian [AUC 0.542 vs. 0.564 (p = 0.476) and 0.513 (p = 0.300)] and Mexican [AUC 0.791 vs. 0.672 (p<0.001) and 0.778 (p = 0.575)] cohorts. In the European cohort, it performed similarly to the Balkau score but worse than the Kahn clinical [AUC 0.788 vs. 0.793 (p = 0.091) and 0.816 (p<0.001)]. Diagnostic capacity of our score was better than the Balkau score and comparable to the Kahn clinical one. CONCLUSION: Our clinically-based score shows encouraging results compared to other scores and can be used in populations with differing diabetes prevalence

Table S7: Osteopontin and osteocalcin protein levels

Background The receptor activator of nuclear factor kappa-B (RANK)/RANK ligand/osteoprotegerin (OPG) system plays a critical role in bone remodelling by regulating osteoclast formation and activity. OPG has been used systemically in the treatment of bone diseases. In searching for more effective and safer treatment for bone diseases, we investigated newly formulated OPG-chitosan complexes, which is prepared as a local application for its osteogenic potential to remediate bone defects. Methods We examined high, medium and low molecular weights of chitosan combined with OPG. The cytotoxicity of OPG in chitosan and its proliferation in vitro was evaluated using normal, human periodontal ligament (NHPL) fibroblasts in 2D and 3D cell culture. The cytotoxicity of these combinations was compared by measuring cell survival with a tetrazolium salt reduction (MTT) assay and AlamarBlue assay. The cellular morphological changes were observed under an inverted microscope. A propidium iodide and acridine orange double-staining assay was used to evaluate the morphology and quantify the viable and nonviable cells. The expression level of osteopontin and osteocalcin protein in treated normal human osteoblast cells was evaluated by using Western blot. Results The results demonstrated that OPG in combination with chitosan was non-toxic, and OPG combined with low molecular weight chitosan has the most significant effect on NHPL fibroblasts and stimulates proliferation of cells over the period of treatment

Efficacy of Miswak (salvadora persica) in preventing dental caries

Senegal: Wood-CarversColorVolume 67, Page 1

Evaluation of Swallowing Patterns of the Tongue Using Real-time B-mode Sonography

Abstract The aim of the present study was to evaluate the swallowing patterns of the tongue using B-mode sonography. A total of 65 patients aged between eight and 35 years were enrolled in the study including 25 controls. The swallowing patterns of the 40 patients were divided into groups of ten normal, 12 inconsistent, and 18 abnormal. Eight patients with a swallowing abnormality had Angle Class I occlusions, two had Class II, and the remaining ten patients had Class III. The majority of abnormal or inconsistent swallowing patterns were found in cases of mandibular prognathism. Quantitative data was not analyzed in this study. The results of this study show that B-mode sonography, being a non-invasive procedure permitting direct visualization of the movements of the tongue in both coronal and sagittal planes, can be used with certainty for diagnosing swallowing abnormalities. Citation Ardakani FE. Evaluation of Swallowing Patterns of the Tongue Using Real-time B-mode Sonography. J Contemp Dent Pract 2006 July;(7)3:067-074. </jats:sec