Association between metabolic score for insulin resistance and clinical outcomes: insights from the Tehran lipid and glucose study.

BACKGROUND: We aimed to assess the relationship between Metabolic Score for Insulin Resistance (METS-IR) and the incidence of coronary heart disease (CHD), stroke, mortality, diabetes, hypertension, and chronic kidney disease (CKD) in a population from the Middle East and North Africa (MENA) region. METHOD: Individuals aged ≥ 20 years were enrolled. Cox proportional hazards regression models were applied to assess the association between METS-IR and incident CHD, stroke, all-cause mortality, diabetes, hypertension, and CKD. RESULTS: Over a median follow-up period of 9-18 years, 1080 (10.6%), 267 (2.6%), 1022 (9.6%), 1382 (16.4%), 2994 (58.5%), and 2002 (23.0%) CHD, stroke, all-cause mortality, diabetes, hypertension, and CKD events occurred, respectively. Compared to the lowest quartile (reference), the hazard ratios (HR) associated with the highest quartile of METS-IR were 1.527 (95% confidence interval [CI]: 1.208-1.930, P for trend 0.001), 1.393 (0.865-2.243, > 0.05), 0.841 (0.682-1.038, > 0.05), 3.277 (2.645-4.060, < 0.001), 1.969 (1.752-2.214, < 0.001), and 1.020 (0.874-1.191, > 0.05) for CHD, stroke, all-cause mortality, diabetes, hypertension, and CKD, respectively. METS-IR, as a continuous variable, was significantly associated with the risk of incident CHD [HR, 95% CI: 1.106, 1.034-1.184], diabetes [1.524, 1.438-1.616], and hypertension [1.321, 1.265-1.380]. These associations were also independent of metabolic syndrome (METS) and remained unchanged in a subgroup of individuals without METS and/or diabetes. CONCLUSIONS: Increasing levels of METS-IR were significantly associated with a greater risk of incident CHD, diabetes, and hypertension; therefore, this index can be a useful tool for capturing the risk of these clinical outcomes.

JAK Inhibitors in Cutaneous T-Cell Lymphoma: Friend or Foe? A Systematic Review of the Published Literature.

Cutaneous T-cell lymphomas (CTCLs) are a group of lymphoid neoplasms with high relapse rates and no curative treatment other than allogeneic stem cell transplantation (allo-SCT). CTCL is significantly influenced by disruption of JAK/STAT signaling. Therefore, Janus kinase (JAK) inhibitors may be promising for CTCL treatment. This study is a systematic review aiming to investigate the role of JAK inhibitors in the treatment of CTCL, including their efficacy and safety. Out of 438 initially searched articles, we present 13 eligible ones. The overall response rate (ORR) in the treatment with JAK inhibitors in clinical trials was 11-35%, although different subtypes of CTCL showed different ORRs. Mycosis fungoides showed an ORR of 14-45%, while subcutaneous-panniculitis-like T-cell lymphoma (SPTCL) displayed an ORR ranging from 75% to 100%. Five cases were reported having a relapse/incident of CTCL after using JAK inhibitors; of these, three cases were de novo CTCLs in patients under treatment with a JAK inhibitor due to refractory arthritis, and two cases were relapsed disease after graft-versus-host disease treatment following allo-SCT. In conclusion, using JAK inhibitors for CTCL treatment seems promising with acceptable side effects, especially in patients with SPTCL. Some biomarkers, like pS6, showed an association with better responses. Caution should be taken when treating patients with an underlying autoimmune disease and prior immunosuppression.

Rapid decline of kidney function increases fracture risk in the general population: Insights from TLGS.

BACKGROUND: Although the association between Chronic Kidney Disease (CKD) and all-cause fractures was addressed in previous studies, the association between estimated glomerular filtration rate (eGFR) decline and fractures was poorly addressed. For the first time we examined the association between rapid kidney function decline (RKFD) and fracture incidence among Iranian general population. METHODS: In a Tehranian community-based cohort, RKFD was defined as a 30 % decline in eGFR over 2-3 years. Cox proportional hazards models, adjusted for age, sex, current eGFR, diabetes mellitus, hypertension, dyslipidemia, current smoking, obesity status, waist circumference, prevalent cardiovascular diseases, aspirin, steroid use, education level, and marital status, were used to examine the association of RKFD with different fracture outcomes. RESULTS: Among 5305 (3031 women) individuals aged ≥30 years, during the median follow-up of 9.62 years, 226 fracture events were observed. The multivariable hazard ratio of RKFD for any-fracture events, lower-extremity, and major osteoporotic fractures were 2.18 (95 % CI, 1.24-3.85), 2.32 (1.15-4.71), and 2.91 (1.29-6.58), respectively. These associations remained significant after accounting for the competing risk of death. The impact of RKFD on the development of incident all-cause fractures was not modified by gender [men: 2.64 (1.11-6.25) vs. women: 2.11 (1.00-4.47)] and according to current CKD status [without CKD: 2.34 (1.00-5.52) vs. with CKD: 2.59 (1.04-6.44)] (all P for interaction >0.5). CONCLUSIONS: RKFD can increase the incidence of fractures among general population, the issue that was equally important among non-CKD individuals, emphasizing the need for early identification and management in those with rapidly declining eGFR.

Radiographic texture analysis of the hard tissue changes following socket preservation with allograft and xenograft materials for dental implantation: a randomized clinical trial.

OBJECTIVES: This study aimed to assess the hard tissue changes following socket preservation with allograft and xenograft materials for dental implantation by texture analysis (TA) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This prospective clinical trial was conducted on 25 patients who required the extraction of carious mandibular posterior teeth and their subsequent replacement with dental implants. The patients were categorized into three groups: (I) no socket preservation, (II) socket preservation with xenograft material, and (III) socket preservation with allograft material. Four months after tooth extraction, the patients were recalled for preoperative assessment before dental implantation, and CBCT scans were obtained (Kvp:110, mA:1.94, S:3.6). MaZda software was used to compare homogeneity, contrast, and texture complexity on axial CBCT sections among the three groups. RESULTS: Significant differences existed among the three groups in all parameters (P < 0.05) except for the mean correlation parameter (P > 0.05). The results showed no significant difference between the no graft and xenograft groups regarding contrast and differential (dif.) entropy (P > 0.05). Also, no significant difference was found between the xenograft and allograft groups regarding the dif. variance and also between the no graft and allograft groups regarding the inverse difference moment(InvDfMom) and dif. variance parameters (P > 0.05). All other pairwise comparisons revealed significant differences (P < 0.05). CONCLUSION: TA can be used for the quantification of radiographic changes of bone following socket preservation and potentially accelerate the process of decision-making for dental implant treatment.

Gender differences in change of metabolic syndrome status and its components on all-cause and cause-specific mortalities: Over a decade follow-up study.

BACKGROUND: Accumulating evidence suggests a close association between metabolic syndrome (MetS) and excess risk of mortality. However, whether the dynamic change of MetS and its components could affect cause-specific mortalities and how this relation could be influenced by gender is yet to be clarified. METHODS AND RESULTS: In this longitudinal cohort, we entered 4904 Iranian adults>30 years (2820 women) from March-1999 and followed up until December-2018. MetS was determined using the joint interim societies (JIS) criteria. Due to change in MetS status over three years, we divided individuals into MetS-free, MetS-recovery, MetS-developed, and MetS-persistent groups. The same categories were defined for each MetS component. Multivariate Cox regression models were employed to compute the adjusted hazard ratios (HRs) and female-to-male relative HRs (F/M-RHRs) for risk of all-cause, cardiovascular (CV), non-CV, and cancer mortalities. To resolve reverse causation, mortalities during the first three years of follow-up were excluded. Subgroup analysis was conducted for non-diabetic and non-hypertensive participants. During 12.5 years of follow-up, 357 all-cause, 112 CV-, and 79 cancer-mortalities occurred. Compared to MetS-free, MetS-persistent raised all-cause- and CV-mortalities in both genders. Same association was found for non-diabetic (HR = 1.66 (1.03-3.00)) or non-hypertensive (HR = 1.89 (1.09-3.64)) women. Moreover, MetS-persistent women with neither hypertension nor diabetes had increased all-cause mortality risk by 88% (F/M-RHR = 3.99 (1.53-5.58)). Women with stable MetS had excess risk of cancer-mortality by 40% (F/M-RHR = 1.63 (1.02-5.06)). Generally, among both genders, recovery from MetS declined risk of mortality events. Regarding MetS components, persistent elevated fasting plasma glucose (FPG) was related to all-cause mortality in both genders, but with stronger association in women (F/M-RHR = 1.41 (1.11-2.49), and CV-mortality only in women (F/M-RHR = 3.04 (1.02-5.96). Both development and stable status of high blood pressure (BP) increased the risk of CV-mortality merely in women (F/M-RHR = 3.10 (0.60-6.87) and F/M-RHR = 3.24 (1.26-6.11), respectively). Development or recovery from each Triglyceride, HDL-C, and waist circumference variables did not solely affect risk of mortality events in both genders. CONCLUSION: Stable status of MetS could increase risk of mortalities with an overall stronger association in women. Although elevated BP and FPG are the main drivers for mortality risk, MetS among women could carry the corresponding effect even in absence of hypertension and diabetes.

Metal Artifact Suppression in Dental Cone Beam Computed Tomography Images Using Image Processing Techniques.

BACKGROUND: Dental cone beam computed tomography (CBCT) images suffer from severe metal artifacts. These artifacts degrade the quality of acquired image and in some cases make it unsuitable to use. Streaking artifacts and cavities around teeth are the main reason of degradation. METHODS: In this article, we have proposed a new artifact reduction algorithm which has three parallel components. The first component extracts teeth based on the modeling of image histogram with a Gaussian mixture model. Striking artifact reduction component reduces artifacts using converting image into the polar domain and applying morphological filtering. The third component fills cavities through a simple but effective morphological filtering operation. RESULTS: Finally, results of these three components are combined into a fusion step to create a visually good image which is more compatible to human visual system. CONCLUSIONS: Results show that the proposed algorithm reduces artifacts of dental CBCT images and produces clean images.

Comparison of Digital Diagnostic Value and Cone Beam Computed Tomography (CBCT) in Determining Vertical Root Fracture in Single- Root Teeth

Objective: To compare the accuracy of digital radiography and CBCT for the diagnosis of vertical root fractures in single root teeth. Material and Methods: For this descriptive-analytic study, 50 non-fractured, single-root teeth were selected. The teeth were randomly divided into a control and an experimental group (25 teeth in each group). The teeth in the control group did not have vertical root fractures. In the test group, after preparing the access cavity, the root canal was cleared and loosened up to No. 80 file, then a vertical root fracture was created by one of the K-Reamers Nos. 90- 130.The images were prepared by CBCT radiography in axial and cross-sectional slices and in digital radiography with PSP sensors at mesial, distal, and parallel angles. The Chi-square test was used to express the correlation of variables. Results: In the diagnosis of vertical root fractures, the sensitivity of CBCT in the axial section was 32% and in the cross-sectional slice it was 20%, whereas the specificity in both the sections was 100%. The sensitivity of the digital radiography in detecting vertical root fractures for parallel, mesial, and distal angles was 38%, 16%, and 24%, respectively. Conclusion: According to this study, the sensitivity, specificity, and accuracy of digital radiography and CBCT were not significantly different.

Correction to: Efficacy of radiographic density values of the first and second cervical vertebrae recorded by CBCT technique to identify patients with osteoporosis and osteopenia.

[This corrects the article DOI: 10.15171/joddd.2017.034.].

Facial Soft Tissue Thickness of Midline in an Iranian Sample: MRI Study.

BACKGROUND AND AIM: To identify human skeletal remains, different methods can be used and using these techniques, important data can be obtained. However, facial reconstruction is the last method to indentify unknown human faces which requires knowledge about facial soft tissue thickness in the different positions of the face. The present study determined the facial soft tissue thickness in the different landmark points on the MRI images of patients referred to Radiology Department of Shahid Madani Hospital. MATERIALS AND METHODS: In this descriptive cross-sectional trial, MRI images of 179 patients (61 males, 118 females) in the age range of 18-76 years old who did not show any pathologic lesions, were selected. The measurements of the facial soft tissue were done on 12 landmark points on the midline area by two radiologist observers using specific software on the images. The differences in the soft tissue thickness in these landmark points were statistically analyzed by Mann-Whitney U (in term of gender) and Kruskal-Wallis tests (in terms of Body Mass Index [BMI] and age groups). P value less than 0.05 was considered statistically significant. The data were compared with the results of other studies. RESULTS: The results obtained in the present study were higher than Turkish and American studies in most of the landmark points. Facial soft tissue thickness in most of the landmarks was more in males than females. In some of the landmarks, significant differences were found between emaciated, normal and overweight patients while in most cases, soft tissue thickness increased with the increased BMI. In some cases, significant differences were noted between soft tissue thickness values among the different age groups, in which the thickness increased or thinned with the increased age. STATISTICAL ANALYSIS: There were statistically significant associations between the presence and surface area of Haller cells and the occurrence of ipsilateral maxillary sinusitis. Neither the angulation of the uncinate process nor the size of the maxillary sinus ostium significantly correlates with the formation of maxillary sinusitis. CONCLUSION: The data achieved in the present study can be used for the facial reconstruction purposes in the Iranian population; however, the slight differences existing between the studied population and other subgroup races must be considered for accurate reconstructions.

Detection of vertical root fractures in intact and endodontically treated premolar teeth by designing a probabilistic neural network: an ex vivo study.

OBJECTIVES: Detection of vertical root fractures (VRFs) in their initial stages is a crucial issue, which prevents the propagation of injury to the adjacent supporting structures. Designing a suitable neural network-based model could be a useful method to diagnose the VRFs. The aim of this study was to design a probabilistic neural network (PNN) to diagnose the VRFs in intact and endodontically treated teeth of periapical and CBCT radiographs. Also, we have compared the efficacy of these two imaging techniques in the detection of VRFs. METHODS: A total of 240 radiographs of teeth (120 radiographs of teeth with no VRFs and 120 teeth with vertical fractures, with half of the teeth in each category treated endodontically and the remaining half intact, i.e. not endodontically treated) were used in 3 groups for training and testing of the neural network as follows: Group 1, 180/60; Group 2, 120/120; and Group 3, 60/180. First, Daubechies 3 wavelet was applied to acquire the image analysis coefficients on two planes; then Gabor filters were used to extract the image characteristics, which were used to educate the PNN. The designed neural network was able to diagnose and classify teeth with and without VRFs. In addition, in order to determine the best training and test sets in the network, the variance of the function of network changes was manipulated at a range of 0-1 and the results were assessed in terms of the parameters evaluated, including sensitivity, specificity and accuracy. RESULTS: In the periapical radiographs, the maximum accuracy, sensitivity and specificity values in the three groups were 70.00, 97.78 and 67.7%, respectively. These values in the CBCT images were 96.6, 93.3 and 100%, respectively, at the variance change range of 0.1-0.65. CONCLUSIONS: The designed neural network can be used as a proper model for the diagnosis of VRFs on CBCT images of endodontically treated and intact teeth; in this context, CBCT images are more effective than similar periapical radiographs. Limitations of this study are the use of sound one-rooted premolar teeth without carious lesions and dental fillings and not simulating the adjacent anatomic structures. Further in vitro work using a full-skull simulation for CBCT and skin/bone simulation is needed.

A Novel Thresholding Based Algorithm for Detection of Vertical Root Fracture in Nonendodontically Treated Premolar Teeth.

In this paper, an efficient algorithm is proposed for detection of vertical root fractures (VRFs) in periapical (PA), and cone-beam computed tomography (CBCT) radiographs of nonendodontically treated premolar teeth. PA and CBCT images are divided into some sub-categories based on the fracture space between the two fragments as small, medium, and large for PAs and large for CBCTs. These graphics are first denoised using the combination of block matching 3-D filtering, and principle component analysis model. Then, we proposed an adaptive thresholding algorithm based on the modified Wellner model to segment the fracture and canal. Finally, VRFs are identified with a high accuracy through applying continuous wavelet transform on the segmented radiographs and choosing the most optimal value for sub-images based on the lowest interclass variance. Performance of the proposed algorithm is evaluated utilizing the different tested criteria. Results illustrate that the range of specificity deviations for PA and CBCT radiographs are 99.69 ± 0.22 and 99.02 ± 0.77, respectively. Furthermore, the sensitivity changes from 61.90 to 77.39 in the case of PA and from 79.54 to 100 in the case of CBCT. Based on our statistical evaluation, the CBCT imaging has the better performance in comparison with PA ones, so this technique could be a useful tool for clinical applications in determining the VRFs.

Beam hardening artifacts by dental implants: Comparison of cone-beam and 64-slice computed tomography scanners.

BACKGROUND: Cone beam computed tomography (CBCT) is an alternative to a computed tomography (CT) scan, which is appropriate for a wide range of craniomaxillofacial indications. The long-term use of metallic materials in dentistry means that artifacts caused by metallic restorations in the oral cavity should be taken into account when utilizing CBCT and CT scanners. The aim of this study was to quantitatively compare the beam hardening artifacts produced by dental implants between CBCT and a 64-Slice CT scanner. MATERIALS AND METHODS: In this descriptive study, an implant drilling model similar to the human mandible was used in the present study. The implants (Dentis) were placed in the canine, premolar and molar areas. Three series of scans were provided from the implant areas using Somatom Sensation 64-slice and NewTom VGi (CBCT) CT scanners. Identical images were evaluated by three radiologists. The artifacts in each image were determined based on pre-determined criteria. Kruskal-Wallis test was used to compare mean values; Mann-Whitney U test was used for two-by-two comparisons when there was a statistical significance (P < 0.05). RESULTS: The images of the two scanners had similar resolutions in axial sections (P = 0.299). In coronal sections, there were significant differences in the resolutions of the images produced by the two scanners (P < 0.001), with a higher resolution in the images produced by NewTom VGi scanner. On the whole, there were significant differences between the resolutions of the images produced by the two CT scanners (P < 0.001), with higher resolution in the images produced by NewTom VGi scanner in comparison to those of Somatom Sensation. CONCLUSION: Given the high quality of the images produced by NewTom VGi and the lower costs in comparison to CT, the use of the images of this scanner in dental procedures is recommended, especially in patients with extensive restorations, multiple prostheses and previous implants.

Beam Hardening Artifacts: Comparison between Two Cone Beam Computed Tomography Scanners.

BACKGROUND AND AIMS: At present, cone beam computed tomography (CBCT) has become a substitute for computed tomography (CT) in dental procedures. The metallic materials used in dentistry can produce artifacts due to the beam hard-ening phenomenon. These artifacts decrease the quality of images. In the present study, the number of artifacts as a result of beam hardening in the images of dental implants was compared between two NewTom VG and Planmeca Promax 3D Max CBCT machines. MATERIALS AND METHODS: An implant drilling model was used in the present study. The implants (Dentis) were placed in the canine, premolar and molar areas. Scanning procedures were carried out by two CBCT machines. The corresponding sections (coronal and axial) of the implants were evaluated by two radiologists. The number of artifacts in each image was determined using the scale provided. Mann-Whitney U test was used for two-by-two comparisons at a significance level of P<0.05. RESULTS: There were statistically significant differences in beam hardening artifacts in axial and coronal sections between the two x-ray machines (P<0.001), with a higher quality in the images produced by the NewTom VG. CONCLUSION: Given the higher quality of the images produced by the NewTom VG x-ray machine, it is recommended for imaging of patients with extensive restorations, multiple prostheses or previous implant treatments.

Comparison of the inclination of unerupted mandibular third molars on panoramic radiography and casts made after surgical incision.

BACKGROUND AND AIMS: Panoramic radiographs are used for surgical planning of unerupted third molars. The major prob-lems associated with panoramic radiography include unequal magnification and geometric distortion of the image. The purpose of this study was the clinical evaluation of the effect of radiographic distortion on the position and classification of unerpted mandibular third molars. MATERIALS AND METHODS: Panoramic radiographs of 20 patients with indication for extraction of lower third molars were included in this study. On the day of surgery, a silicon impression was taken from the second and third molar region and poured with type IV gypsum to provide a study cast. The inclination of the lower third molar to the second molar on panoramic radiog-raphy was compared with this angulation on the study casts. RESULTS: There was a mean difference of 5.75° ± 1.65 between the position of the lower third molar on panoramic radiographs and on study casts. Student's t-test indicated a statistically significant difference (P < 0.05). CONCLUSION: Panoramic radiography tends to exhibit a more mesial position of the third molars; however, panoramic radiog-raphy can still be used as the main tool for surgical planning of lower third molars.

Diagnostic accuracy of digitized conventional radiographs by camera and scanner in detection of proximal caries.

BACKGROUND AND AIMS: Digital radiographs have some advantages over conventional ones. Application of digital recep-tors is not routine yet. Therefore, there is a need for digitizing conventional radiographs. The aim of the present study was to compare the diagnostic accuracy of digitized conventional radiographs by scanner and camera in detection of proximal car-ies. MATERIALS AND METHODS: Three hundred and sixteen surfaces of 158 extracted posterior teeth were radiographed. The radiographs were digitized using a digital camera and a scanner. Five observers scored the images for the presence and depth of caries. Histopathologic sections were the gold standard. Kappa agreement coefficient was used for statistical analysis. RESULTS: Kappa agreement coefficients between the camera and the scanner and also between each one with the gold stan-dard in detecting the depth of caries were 0.504, 0.557 and 0.454, respectively. In detection of caries, the indexes were 0.571, 0.553 and 0.527, respectively. CONCLUSION: Diagnostic accuracy of camera images in caries detection was more than that of scanned images, but there was also a moderate consistency between them. The consistency of detecting the presence of caries was more than that of detecting their depths. It seems that both digital cameras and scanners can be used interchangeably.

Accuracy of digital subtraction radiography in combination with a contrast media in assessment of proximal caries depth.

BACKGROUND AND AIMS: Radiography is used to diagnose the demineralization process and carious lesions; however, conventional radiography and direct digital images do not show these lesions when the amount of demineralization is less than 40%. Digital subtraction radiography has recently been used to improve the diagnostic quality of these le-sions. The purpose of this study was to compare the caries depth estimated by digital subtraction radiog-raphy in combination with barium sulfate in diag-nosing proximal dental caries with histopathologic evaluation. MATERIALS AND METHODS: In this study 30 molars and premolars (24 demineralized lesions with cavity, 8 without cavity) were studied. Direct digital images were taken (kVp: 68, mA: 8; t: 0.12 for premolars and t: 0.16 for molars) whereas the position of X-ray tube and CCD receptor and teeth was fixed. To prepare the second images 135 gr/L barium sulfate was used. The images obtained with the same exposure and geometry and then subtracted. The depth of the lesions in direct digital and subtracted images were assessed and compared with the depth measured in histopathologic assessments. RESULTS: The mean depths (± SD) of the lesions were 1.80 ± 0.77 mm in direct digital radiography, 2.32 ± 0.76 mm in subtracted images after barium sulfate treatment, and 2.51 ± 0.43 mm in histopathologic sections. The statistical difference between direct digital radiography and the other methods was significant (P < 0.05). However, the differences were not statistically significant between subtracted images and histopathologic sections. The average intra-class correlation coefficient was 0.7241 (CI: 95%). CONCLUSION: The present study has demonstrated that digital subtraction radiography images have the potential to measure the depth of proximal caries with no significant difference with histopathologic evaluation.

Evaluation of common errors of panoramic radiographs in tabriz faculty of dentistry.

BACKGROUND AND AIMS: Knowledge of the common radiographic errors and their prevention could prevent imposing redundant radiation, time and money to patient and the dentist. The aim of this study was to assess the common radiographic errors on panoramic radiographs in a radiology department. MATERIALS AND METHODS: 250 panoramic radiographs (100 male and 150 female; mean age, 24.3) taken at the Department of Oral and Maxillofacial Radiology were evaluated. Radiographs were categorized into five groups according to the type of errors (patient positioning errors, darkroom errors, failure to remove metallic accessories, equipment setup errors, and patient movement during exposure). RESULTS: here were19 error-free radiographs. The number of radiographs with errors was 231, of which 26 were unacceptable and had to be retaken. Errors of patient positioning were observed in 78% of cases, film de-velopment in 69.2%, equipment setup in 3.2%, failure to remove metallic accessories in 3.2% and patient move-ment during exposure in 2.4% of cases. CONCLUSION: The errors seen on panoramic radiographs were relatively high with errors in patient positioning being the most frequent error.

Root Canal Configuration of One-rooted Mandibular Canine in an Iranian Population: An In Vitro Study.

BACKGROUND AND AIMS: A perfect endodontic treatment necessitates proper understanding of the morphology of canal and pulpal variations. This in vitro study was conducted to demonstrate the in-ternal anatomy of mandibular canine teeth in an Iranian population. MATERIALS AND METHODS: The samples consisted of 100 extracted mandibular permanent canines. The roots of the teeth were molded in acrylic boxes. The crowns of the teeth were cut and 2 mm cross sections were made from CEJ to the apex. Sections were examined using stereomicroscope to reveal the number and location of root canals. RESULTS: From 100 evaluated teeth, 12 (12%) had 2 canals from which 5 had type II canal configu-ration and 7 (7%) had type III. 88% of the specimens had one canal and none were seen to be of type IV. CONCLUSION: The findings of this study emphasize the importance of dentist's knowledge of varia-tions in root canal morphology, since leaving a canal untreated is one of the main reasons of endodontic failures. When treating mandibular canines, the existence of a second canal should be taken into consideration.

Serum Interleukin-6 as a Serologic Marker of Chronic Periapical Lesions: A Case-control Study.

BACKGROUND AND AIMS: Chronic periapical disease with pulpal origin is an inflammatory condition caused by bacterial infection. Chronic infection could affect general health by increasing the production of cytokines such as interleukin-6 (IL-6) that probably play a role in pathogenesis of pulpal and periapical diseases. The aim of the present study was a comparative evaluation of the level of serum IL 6 in patients with periapical lesions and healthy controls. MATERIALS AND METHODS: This analytical case-control study included 40 patients with chronic peri-apical lesions and 40 individuals without any oral diseases. All of the participants were in good general health. After obtaining an informed consent, clinical and radiographic examinations were carried out and blood samples were collected. Serum IL-6 was measured using ELISA. Data were analyzed using t-test by SPSS 14.0 computer software. RESULTS: Serum IL-6 concentration was significantly higher in test group compared to the controls (P < 0.05). CONCLUSION: The results of the present study indicate that IL-6 produced in periapical lesions may serve as a marker of pathologic inflammatory activities in chronic periapical lesions.

Evaluation of X-ray Protection Methods Used in Dental Offices in Tabriz in 2005-2006.

BACKGROUND AND AIMS: The aim of this study was to evaluate x-ray protection methods in dental offices in Tabriz. MATERIALS AND METHODS: In this study 142 dental offices were evaluated. A questionnaire-based method was used. The data was analyzed by descriptive methods. RESULTS: The least commonly used methods were leaded walls (4.9%) and film badges (16.9%) and the most commonly used methods were lead partitions (67.6%) and position-distance rule (68.3%). The most commonly used patient protection devices were E-speed films (84.5%) and long collimators (66.2%). The least commonly used methods, in this respect, were automatic processors (2.1%) and rectangular collimators (0%). CONCLUSION: Regarding protection methods for the patient, results did not conform to international standards. Mostly, manual processing was used, resulting in extra radiation dose to patients. The methods which reduce the received dose of patients were disregarded in offices compared to educational centers, necessitating optimization of educational programs in these fields.