MATERIAL AND METHOD: Forty sound permanent mandibular premolars were collected from a dental clinical setting and disinfected. All forty samples were mounted vertically in a rubber mold exposing only the clinical crown. All samples were bleached using Opalescence Boost Professional Teeth Whitening. After the bleaching procedure, each sample was randomly allocated into four groups according to surface treatment. Samples in group 1 were treated with methylene blue photosensitizer (MBP). Samples in group 2 were exposed to 10% sodium ascorbate. Samples in group 3 were treated with Er, Cr: YSGG laser (ECL). Samples in group 4 were not treated (control). All Samples were treated with 37% phosphoric acid and a bonding agent was applied. A bulk-fill composite was cured to all specimens and all samples were treated in a thermocycler. Specimens were placed in a universal testing machine for shear bond strength (SBS) testing. Descriptive statistics were associated by analysis of variance (ANOVA) and Tukey's post hoc test maintaining level of significance (p<0.05) RESULTS: The lowest SBS scores were achieved in the bleached enamel (BE) group (15.25±1.745 MPa). Whereas, the highest bond integrity was attained by AA group (32.23±1.854 MPa). Samples treated with ECL (31.87±1.659 MPa) and AA (32.23±1.854) were comparable (p>0.05). Samples treated with PDT exhibited significantly different SBS (22.41±1.258) compared to other experimental groups CONCLUSION: ECL showed a reversal effect of BE compared to AA and has the potential to be used in clinical settings. BE reversal using MBP needs further investigation.
METHODS: The selected patients were divided into three groups, Group I (PDT + SRP), Group II (SP + SRP) and group III (SRP alone). Clinical inflammatory periodontal parameters including plaque index (PI), bleeding on probing (BOP), probing depth (PD) and clinical attachment level (CAL) gain were assessed. Assessment of crevicular fluid interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) was performed using enzyme-linked immunosorbent assay technique. All measurements were recorded at baseline, 3 months and 6 months follow-up periods, respectively.
RESULTS: A total of 73 patients completed the study. A significant improvement in the BOP was seen in Group II at both follow up visits when compared with other groups (p < 0.05). Only in Group-I that showed statistically significant reduction in moderate periodontal pockets at 3 months (p = 0.021), and significant reductions in deep pockets at 3-months (p = 0.003) and 6-months (p = 0.002), respectively. CAL gain also was reported to be seen in group-I at both visits (p < 0.05). Group- I and II significantly reduced the levels of IL-6 at 3-month period compared to Group-III. This reduction was further maintained by group-II and group-III at 6 months, respectively. TNF-α showed statistically significant decrease in Group II as compared to Group I and Group-III and this reduction was maintained by the end of 6-month visit (p = 0.045).
CONCLUSION: Both the treatment modalities PDT and SP helped in reducing periodontal inflammation. PDT reported significant gain in clinical attachment level, whereas the SP significantly reduced the bleeding levels.