Effect of laser application on microtensile bond strength of an orthodontic adhesive to water-aged composite.

AIM: This study evaluated the microtensile bond strength (MTBS) of an orthodontic adhesive to water-aged composite surfaces using different surface treatments. SUBJECTS AND METHODS: Twelve composite blocks (10 mm × 10 mm × 5 mm) were fabricated and randomly divided into two groups. Half of the specimens were stored in distilled water for 1 day, and the other specimens were stored for 30 days. The specimens were randomly assigned to six groups according to surface treatments (n = 15): Group 1, control (no treatment); Group 2, phosphoric acid; Group 3, diamond bur; Group 4, diamond bur + phosphoric acid; Group 5, laser; and Group 6, laser + phosphoric acid. One coat of orthodontic adhesive was bonded to one surface of composite blocks, and a microhybrid composite resin was bonded to the surfaces via a Teflon mold. Bond strength was evaluated using an MTBS test. Surface topography was evaluated using scanning electron microscopy (SEM) analysis. The data were analyzed using one-way analysis of variance, Tamhane post-hoc test, and independent sample t-tests (P < 0.05). RESULTS: Bond strength values tended to decrease in all groups (with the exception of Group 2) after storage in water for 30 days (P < 0.05). Laser and diamond bur application (with or without phosphoric acid) enhanced the bond strength. CONCLUSIONS: An Er,Cr:YSGG laser application may be a feasible alternative to diamond bur for enhancing the bond strength of orthodontic adhesive to composite resin.

Antimicrobial activity and volatile constituent analysis of three commercial herbal toothpastes containing Aloe vera L. and Fragaria vesca L. extracts.

AIMS: This work was designed to evaluate the antimicrobial activity of three different commercial herbal (Aloe vera L. and Fragaria vesca L. extracts) toothpastes [LR Aloe vera (HTP1), ESI Aloe fresh (HTP2) and ROCS Teens (HTP3)] against two microorganisms that cause tooth infections. MATERIALS AND METHODS: An agar disk diffusion method was used to test the antimicrobial activity of three herbal gel toothpastes in the amount of 100 µL against Streptococcus mutans and Staphylococcus aureus. In the second part of the work, the volatile organic compounds of three different commercial herbal toothpastes (HTP1-3) were determined by solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (SPME/GC-MS-FID). RESULTS: The sensitivity of the tested herbal toothpastes toward each microorganism was expressed as the mean of the clear zone within the range of 6-16 mm diameters. HTP1 and HTP2 were found to be more effective against both bacteria compared with HTP3. Oxygenated monoterpenes (99.34%, 91.44%, and 83.48%) were the most abundant groups in the SPME of HTP1-3, respectively. Menthol (25.41%, 35.82%, and 31.15%) and anethole (52.01%, 23.62%, and 38.79%) were the major compounds identified in the SPME analysis of HTP1-3, respectively. Carvone was found only in HTP3 (0.49%) in a small quantity. CONCLUSION: The commercial herbal toothpastes could have advantages in decreasing bacterial accumulation on teeth with protection of the oral cavity.