Effect of antimicrobial photodynamic therapy on the counts of salivary Streptococcus mutans in children with severe early childhood caries.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a novel technique for reduction of pathogenic microorganisms in dentistry. The aim of this study was to evaluate the effects of aPDT on Streptococcus mutans reduction in children with severe early childhood caries. METHODS: Twenty-two children with severe early childhood caries aged 3-6 years were treated with toluoidine blue O (TBO) for 1min and irradiated by a Light Emitting Diode (LED; FotoSan, CMS Dental, Denmark) with the exposure time of 150s. Saliva samples were collected at baseline, 1h and 7 days after treatment. S. mutans counts were determined using the Dentocult SM Strip mutans. RESULTS: The counts of S. mutans in saliva decreased significantly after 1h (P<0.001). However, the difference in reduction of S. mutans counts in saliva was not significant between the baseline and 7 days after treatment (P>0.05). CONCLUSION: aPDT seems to be efficient to reduce salivary S. mutans immediately after treatment in children with severe early childhood caries. However, further research is needed to evaluate different doses and frequency of irradiation in combination with restoring carious teeth to find more durable results.

Comparative study of substance P and neurokinin A in gingival crevicular fluid of healthy and painful carious permanent teeth.

BACKGROUND: It is shown that neuropeptides can be transported from pulp chamber to periodontal ligament through apical foramen and accessory canals. Therefore, clinical pulpal pain leads to expression of preinflammatory neuropeptides such as substance P (SP) and neurokinin A (NKA) in gingival crevicular fluid (GCF). This study aimed to evaluate levels of SP and NKA in GCF of carious and healthy permanent teeth, comparatively. MATERIALS AND METHODS: This cross-sectional study was performed on twenty children referred to Department of Pediatric Dentistry, Tehran University of Medical Sciences, who had a painful permanent first molar. Sampling was done by sterile paper cone from GCF of the mentioned teeth and the intact tooth of the other side of the jaw in the same patient. Values of SP and NKA were measured by ELISA test. RESULTS: The mean concentration of SP in GCF of painful carious and healthy teeth was 2.65 ± 0.56 and 1.83 ± 0.65 pcgr/ml, respectively. This value was 2.29 ± 0.29 and 1.61 ± 0.35 pcgr/ml for NKA concentration in carious and healthy teeth as well. CONCLUSION: Significant higher levels of both SP and NKA in GCF of painful carious teeth were observed, which is in line with previous studies' findings.

Radiographic evaluation of the mental foramen in a selected Iranian population.

BACKGROUND: Information on the position of the mental foramen is important for dental surgeons. Variations in its position can be a cause of complications during local anesthesia or surgical procedures. The usual position of the mental foramen in an Iranian population has not been previously reported. AIMS: The purpose of this study was to determine the most common location of the mental foramen in an Iranian population. We also analyzed gender differences and the symmetry of location within individuals. MATERIALS AND METHODS: 400 panoramic radiographs were evaluated with regard to the location and symmetry of the mental foramina in male and female subjects. RESULTS: We found that the mental foramen was located between the first and second premolars in 47.2% of patients and in line with the second premolar in 46%. In 49.2% of males, the mental foramen was in line with the second premolar. In 50.9% of females it was between the first and second premolars. It was symmetrical in 85.7%. CONCLUSIONS: Based on this study it appears that the most common position of mental foramen is either between the two premolars or in line with the second premolar. This is in concordance with previous studies.