Patients' perceptions of antimicrobial photodynamic therapy in the management of chronic periodontitis.

The aim of this study is to evaluate patients' perception of antimicrobial photodynamic therapy (aPDT) in the management of chronic periodontitis. 90 patients (51 females and 39 males) with untreated localized chronic periodontitis were randomly assigned to receive SRP with aPDT (test group) or SRP alone (control group) in a single-centered double-blinded randomized and controlled clinical trial. Patients' perception in terms of changes in bleeding gums, pain in gums while chewing, bad breath and sensitive gums along with pain during the procedure and patient acceptance were recorded for 6 months after treatment by a periodontist who was blinded to the procedure. Inter-group and intra-group statistical analyses were performed. Significant difference between the frequencies of two groups with respect to each variable was assessed using non-parametric test. Patients' report of bleeding gums and pain in the gums while chewing showed statistically significant reduction in the test group at 2 weeks and 1 month (p<0.05). Also, a significant difference was detected at 1 month between SRP and SRP+aPDT in terms of halitosis (p<0.05). No statistically significant change was observed between two groups in terms of sensitive gums, pain during procedure and patient acceptance. Patients perceived short-term benefits of single session of aPDT therapy due to the reduction in bleeding gums, halitosis and pain while chewing following treatment. Further studies are required to assess the effectiveness of aPDT for a longer-term and following multiple sessions.

Detection and quantification of dental plaque based on laser-induced autofluorescence intensity ratio values.

The aim of this study was to evaluate the applicability of laser-induced autofluorescence (LIAF) spectroscopy to detect and quantify dental plaque. LIAF spectra were recorded in situ from dental plaque (0­3 grades of plaque index) in 300 patients with 404 nm diode laser excitation. The fluorescence intensity ratio of the emission peaks was calculated from the LIAF spectral data following which their scatter plots were drawn and the area under the receiver operating characteristics were calculated. The LIAF spectrum of clinically invisible grade-1 plaque showed a prominent emission peak at 510 nm with a satellite peak around 630 nm in contrast to grade 0 that has a single peak around 500 nm. The fluorescence intensity ratio (F510/F630) has a decreasing trend with increase in plaque grade and the ratio values show statistically significant differences (p<0.01) between different grades. An overall sensitivity and specificity of 100% each was achieved for discrimination between grade-0 and grade-1 plaque. The clinical significance of this study is that the diagnostic algorithm developed based on fluorescence spectral intensity ratio (F510/F630) would be useful to precisely identify minute amounts of plaque without the need for disclosing solutions and to convince patients of the need for proper oral hygiene and homecare practices.

Discrimination of periodontal diseases using diffuse reflectance spectral intensity ratios.

This clinical study was to demonstrate the applicability of diffuse reflectance (DR) intensity ratio R620/R575 in the quantification and discrimination of periodontitis and gingivitis from healthy gingiva. DR spectral measurements were carried out with white-light illumination from 70 healthy sites in 30 healthy volunteers, and 63 gingivitis- and 58 periodontitis-infected sites in 60 patients. Clinical parameters such as probing pocket depth, clinical attachment level, and gingival index were recorded in patient population. Diagnostic accuracies for discrimination of gingivitis and periodontitis from healthy gingiva were determined by comparison of spectral signatures with clinical parameters. Divergence of average DR spectral intensity ratio between control and test groups was studied using analysis of variance. The mean DR spectrum on normalization at 620 nm showed marked differences between healthy tissue, gingivitis, and periodontitis. Hemoglobin concentration and apparent SO(2) (oxygen saturation) were also calculated for healthy, gingivitis, and periodontitis sites. DR spectral intensities at 545 and 575 nm showed a decreasing trend with progression of disease. Among the various DR intensity ratios studied, the R620/R575 ratio provided a sensitivity of 90% and specificity of 94% for discrimination of healthy tissues from gingivitis and a sensitivity of 91% and specificity of 100% for discrimination of gingivitis from periodontitis.