Caries effected dentin disinfection using Ozone, methylthioninium chloride and turmeric activated by photodynamic therapy on bond integrity of resin-modified glass ionomer cement.

AIM: To evaluate the shear bond strength (SBS) of caries effected dentin (CAD) bonded to resin-modified glass ionomer cement (RMGIC) after being disinfected with different methods their effect on microleakage scores. MATERIAL AND METHODS: Based on criteria of ICDAS seventy-five teeth were selected and disinfected. All samples were grounded and a cavity prepared followed by random allocation of samples into different disinfection groups i.e., methylene blue photosensitizer (MBP), Silver diamine fluoride (SDF), Ozone (O3); curcumin photosensitizer (CP) and chlorhexidine (CHX) (n = 15). All samples were restored with resin modified glass ionomer (RMGIC) incrementally. Ten specimens from each group were placed in universal testing machine (UTM) to calculate bond failure and failure type. Five samples from each group were evaluated for microleakage scores. SBS and microleakage scores was examined using analysis of variance (ANOVA) with a Post-hoc test. For all tests p-value, less than 0.5 was considered statistically significant. RESULTS: The highest SBS was observed in CAD disinfected with CP bonded to RMGIC (16.42 ± 1.10 MPa). Similarly, the lowest bond values were demonstrated by CAD disinfected with MBP (9.21 ± 0.22 MPa) bonded to RMGIC respectively. CAD disinfected with CHX (Control) bonded to RMGIC demonstrated the lowest microleakage scores and showed a significant difference compared to other experimental groups (p< 0.05). CONCLUSION: Curcumin along with O3 has the potential to be used as a disinfectant in CAD as it improves SBS to RMGIC. CHX demonstrates low microleakage scores with decrease of bond integrity.

Does bond integrity of bleached enamel increases with phototherapy? A systematic review.

BACKGROUND: The aim of the current systematic review was to evaluate the efficacy of phototherapy (PT) on bond strength of bleached enamel. METHODS: Electronic databases including MEDLINE (PubMed), ISI Web of Science, Scopus, ScIELO, LILACS and EMBASE until January 2019. The addressed focused question was: "Does PT increase the bond integrity of bleached enamel?" Only in-vitro studies evaluating the effect of PT compared with bleaching agent or no phototherapy were included. The outcome measures of interest was shear bond strength. RESULTS: A total of 5 in-vitro studies were included. Different concentrations of hydrogen peroxide were used in the included studies. The frequency of laser used in the included studies ranged from 20 Hz to 60 Hz. Pulse duration was reported in only 3 studies that ranged from 100 µs to 320 µs. The overall main outcomes of the included studies showed that in 4 studies, application of phototherapy resulted in significantly higher bond integrity of bleached enamel as compared to enamel which underwent acid etching with bleaching alone, while 1 study showed comparable shear bond strength of bleached enamel achieved by PT as compared to bleaching alone. CONCLUSION: The evidence from the current systematic review suggests that phototherapy increases the bond strength of bleached enamel. Further in-vitro studies should be performed in order to obtain stronger conclusions.