Diagnosis of approximal caries after delayed scanning of photostimulable phosphor plates

Statement of the Problem: Considering the high diagnostic accuracy and wide dynamic range of photostimulable phosphor plates [PSPs], they can be a good alternative for radiographic films

Purpose: This study was aimed to assess the effects of delay in scanning PSPs on the diagnostic accuracy of detection of approximal caries

Materials and Method: Radiographs from fifty-two extracted molar and premolar teeth were radiographed using DIGORA PSP [Soredex Corporation, Helsinki, Finland]

The teeth were either intact or with non-cavitated approximal caries. The plates were scanned immediately [time zero] and at 10 min, 30 min, 60 min and 120 min after exposure. Sixty-five images were obtained and evaluated for presence or absence of approximal caries by two oral and maxillofacial radiologists and 2 restorative specialists. The diagnostic accuracy of approximal caries detection was measured using a 5-point rating scale. Definite presence of caries was confirmed using a stereomicroscope. Analysis of caries detection data was performed by calculating sensitivity and specificity using repeated measures with ANOVA

Results: Significant differences were found in complete negative predictive value, absolute negative predictive value and complete dentine sensitivity value between different scan times [p< 0.05]

These values were significantly different at 10 min, 60 min and 120 min [p< 0.05]

However, immediate scan and 30 min delay were not significantly different [p> 0.05]

The accuracy of approximal caries detection at 120 min was less than at 60 min and at 60 min was less than at 30 min. Conclusion: In order to detect approximal caries more accurately, DIGORA PSPs should be scanned within 30 min after exposure

in vitro comparison of antimicrobial effects of curcumin-based photodynamic therapy and chlorhexidine, on aggregatibacter actinomycetemcomitans

Introduction: Considering the importance of prevention in periodontal diseases and the important role of Aggregatibacter actinomycetemcomitans in induction and progression of these diseases, the aim of the present in vitro study was to compare the antimicrobial effects of chlorhexidine digluconate [CHX], curcumin and light-emitting diode [LED] laser, on this bacterium

Methods: Antimicrobial activity of curcumin [5 mg/ml], CHX [2%], LED [120 J/cm[2]] and LED + curcumin [120 J/cm[2] + 2.5 mg/ml] against A. actinomycetemcomitans were tested in vitro, using micro-broth dilution test. One-way analysis of variance [ANOVA] and Tukey's HSD tests served for statistical analysis

Results: Regarding the minimum inhibitory concentration [MIC], CHX had a significantly lower MIC than curcumin [P<0.05]. Sorted out by bacterial growth from lowest to highest, were CHX, LED + curcumin, curcumin, and LED groups. All the differences were found to be statistically significant [P<0.05] except for the LED group

Conclusion: We conclude that curcumin is an effective substance in preventing the growth of A. actinomycetemcomitans, whose impact is reinforced when used simultaneously with photodynamic therapy [PDT]

Mast cells density in fibrotic capsule of enchondroma and well-differentiated chondrosarcoma: a method for histopathologic differentiation

An enchondroma is a benign and a well-differentiated chondrosarcoma is an invasive chondroid tumor with high recurrence potential. In spite of biologic differences, these two tumors have very similar histopathologic appearance. It has been shown that the biologic nature of the connective tissue around benign and malignant tumors varies in the number of mast cells. The aim of this study was to study the histopathologic distinction of enchondroma and well-differentiated chondrosarcoma using the density of the mast cells in fibrotic capsule. Twelve enchondroma and 15 well-differentiated chondrosarcoma were collected from Pathology department of Cancer Institute and Central Pathology department of Imam Khomeini Hospital in Tehran. 3 micron paraffin embedded tissue sections were stained by toluidine blue for mast cells counting. Mast cells were counted in fibrous capsule of all cases. Mast cells counts were accomplished in 10 high power fields .The average number of mast cells in 10HPF was determined as an index for each lesion. Mann-Whitney U test was used for statistical analysis. Mean index in enchondroma and well-differentiated chondrosarcoma groups were 0.1 +/- 0.12 and 0.31 +/- 0.33 respectively, showing a significant difference between number of mast cells in the fibrotic capsule in these two lesions [p=0.028]. Comparison of the corresponding points in ROC curve, showed a cut-off point = 0.15, with positive predictive value of 61%, negative predictive value 71%, specificity of 33.3% and sensitivity of 66.7%, [p=0.025]. Average density of the mast cells in the surrounding fibrotic capsules of enchondroma and well-differentiated chondrosarcoma along with other criterions, could be a beneficial factor for histologically differentiation between these two lesions