Efficiency of activated charcoal powder in stain removal and effect on surface roughness compared to whitening toothpaste in resin composite: In vitro study.

OBJECTIVES: To evaluate the efficacy of activated charcoal powder on extrinsic stain removal and its effect on surface roughness in stained resin composite in comparison with whitening toothpaste. MATERIALS AND METHODS: Sixty-six disk-shaped composite specimens were fabricated using a custom-made ring mold. The specimens were stained using a coffee solution and stored in distilled water at 37 °C. The specimens were divided randomly into two groups, Group 1: Thirty-Three disks were subjected to brushing using whitening toothpaste (Control), and Group 2: Thirty-Three disks were subjected to brushing using charcoal powder. Specimens were evaluated for surface color and surface roughness at baseline after staining protocol and after the brushing process. RESULTS: Changes in color and surface roughness were highly significant (p < 0.0001) after brushing with activated charcoal powder and whitening toothpaste. However, no significant differences were found in color (p = 0.90) and surface roughness (p = 0.33) between the two bleaching techniques. CONCLUSION: The changes in the color and surface roughness of resin composite was significant after brushing with activated charcoal powder and whitening toothpaste. However, there were no significant differences between the two techniques.

Effect of Photodynamic Therapy, Er,Cr:YSGG, and Nd:YAG Laser on the Push-Out Bond Strength of Fiber Post to Root Dentin.

Objective: To evaluate the push-out bond strength and modes of failure of fiber post to root dentin by using photodynamic therapy (PDT), Er,Cr:YSGG, Nd:YAG laser, and conventional cleaning and shaping (CCS). Materials and methods: Eighty anterior teeth were sectioned in a horizontal manner being 2 mm incisal to the cementoenamel junction, and root canal was prepared for post space. After post space was made, fiber posts were placed inside the root canal system. The fiber posts were subjected to PDT, Er,Cr:YSGG laser, Nd:YAG laser, and conventional cleaning and shaping (CSS) with 20 specimens in each group. Cervical and apical sections were obtained from the specimens. For performing the push-out test, the universal testing machine was used. The formula used for calculating the push-out bond strength was σ = N/mm2. Results: PDT group (8.16 ± 2.19 MPa) achieved the highest mean push-out bond strength, whereas Er,Cr:YSGG (7.24 ± 1.27 MPa) reported the lowest value in the specimens. Among the experimental groups, the ANOVA test expressed statistical difference (p = 0.481). In the cervical segments, the mean push-out bond strength was found to be higher in all of the experimental groups. For the cervical segments, the independent t-test results showed higher mean push-out bond strength values than the apical segments in PDT, Er,Cr:YSGG, Nd:YAG, and CSS groups, respectively (p < 0.05). Twenty failures were observed at the interface level between the adhesive and surface of dentin. Seven failures were found at the interface between mixed and the adhesive and post, respectively. Conclusions: Push-out bond strength to root canal dentin was not affected by PDT, Er,Cr:YSGG, and Nd:YAG laser compared with CCS. However, PDT produced the smallest number of failure modes and slightly higher push-out bond strength to root dentin. Laser treatment using PDT and Er,Cr:YSGG appeared to be clinically efficient showing acceptable push-out bond strength of fiber post with less number of failures at different regions of the root dentin.

Survival of Titanium-Zirconium and Titanium Dental Implants in Cigarette-smokers and Never-smokers: A 5-Year Follow-up.

OBJECTIVE: To compare the peri-implant clinical and radiographic status around bone-level narrow-diameter titanium-zirconium (TiZr) implants and titanium (Ti) implants placed in cigarette-smokers (CS) and never-smokers (NS). METHODS: Partially edentulous CS and NS rehabilitated with TiZr and Ti implants were included. Demographic data and information regarding smoking habits were collected. Participants were divided into four groups: group-1, CS with TiZr implants; group-2, NS with TiZr implants; group-3, CS with Ti implants; and group-4, NS with Ti implants. 36, 30, 31 and 33 implants were placed in 24, 23, 24 and 25 male individuals in groups 1, 2, 3 and 4, respectively. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and mesial and distal crestal bone loss (CBL) were measured. All patients were enrolled in biannual routine oral prophylaxis care at least until the fifth year of follow-up and oral hygiene instructions were reinforced at each recall appointment. P < 0.05 was considered statistically significant. RESULTS: At the 3- and 5-year follow-ups, there was no statistically significant difference in the peri-implant PI, BOP, PD and CBL between individuals in all groups. In all groups, the implant success and survival rates were 100% and 100%, respectively, at the 5-year follow-up. CONCLUSION: The TiZr and Ti dental implants can remain clinically and radiographically stable in CS in a manner similar to NS. Routine oral hygiene maintenance plays an essential role in this regard.

Influence of Er,Cr:YSGG Laser Irradiation on the Push-Out Bond Strength of Zirconia and Glass Fiber Posts with Radicular Dentin.

OBJECTIVE: This in vitro study was designed to evaluate the influence of an Er,Cr:YSGG laser on the bond strength of zirconia and glass fiber posts with root dentin. MATERIALS AND METHODS: Ninety extracted single-rooted human teeth were randomized into 6 groups (n = 15/group) on the basis of different posts (zirconia/glass fiber) and Er,Cr:YSGG laser tips (axial and radial). Specimens were prepared for push-out testing with the help of a cutting machine; six slices (2 on each cervical, middle, and apical) of approximately 1 mm thickness were sectioned for all roots on a plane perpendicular to the long axis of the post. All specimens were placed into a universal testing machine with a defined 0.5 mm/min crosshead speed until the maximum failure load was obtained. RESULTS: The highest mean push-out bond strength of the glass fiber and zirconia groups was achieved with laser treatment. The highest push-out bond strength was achieved with the axial fiber tip (7.63 ± 1.22 MPa), and the lowest was achieved with a radial fiber tip of the glass fiber group (6.98 ± 0.96 MPa). ANOVA showed a statistically significant difference between the groups (p = 0.041). The mean push-out bond strength was found to be higher with an axial fiber tip for both cervical and apical segments in the glass fiber and zirconia groups (p < 0.05). The independent t-test resulted in the overall highest mean push-out bond strength in the apical segments (p = 0.026). CONCLUSION: Within the limits of the present in vitro research study, an enhancement in the push-out bond strength of resin cement, mainly in the cervical region of the root canal, was achieved after irradiation with an Er,Cr:YSGG laser using an axial fiber tip.

Efficacy of photodynamic therapy versus local nystatin in the treatment of denture stomatitis: A randomized clinical study.

AIM: The aim of the present randomized clinical study was to compare the efficacies of photodynamic inactivation (PDI) to nystatin (NST) in terms of prevalence of Candida species in cases with denture stomatitis (DS). METHODS: Thirty-six patients were randomly divided into two groups; 18 in PDI and 18 in NST. Irradiation was carried out by using the GaA1As diode laser with wavelength, mode of transmission, laser output and energy density were standardized at 660 nm, continuous mode, 100 mW power and 28 J/cm2 respectively. The PDI was applied twice a week, with an interval of at least 48 h among the sessions during four weeks. Topical nystatin oral suspension 100,000 IU was used four times daily for 15 days. The existence of Candida spp. was confirmed by employing the microbiological culture technique. Candida colony counts from the palates and dentures surfaces, quantified as colony forming unit (CFU)/mL, measured at baseline, at the end of treatments (day 15), and at follow-up (days 30 and 60) and the prevalence of Candida spp. were identified in the two groups of treatments. RESULTS: The overall CFU/mL values were higher in the dentures of the patients of both the groups than those from the palates. During all time periods of the study, the CFU/mL values obtained from both NST and PDI groups showed no significant differences. For dentures and palates, a significant reduction in mean CFU/mL values was observed on day 15 compared with baseline (day 0) in both NST and PDI groups. It can be seen that the effect size of treatments was large for the palates of patients in the NST group (1.79) and moderate for the palates of patients in the PDI group (0.63). On the other hand, the effect size was very large for the dentures for both groups (NST group = 3.01; PDI group = 1.58). C. albicans was the most common species on both dentures and palates of patients throughout the study period followed by C. tropicalis and C. glabrata. CONCLUSION: Out of all the Candida spp., C. albicans showed the highest prevalence among all species. In addition, PDI was equally effective as nystatin for the treatment of DS.

Effect of photodynamic therapy and ErCrYSGG laser irradiation on the push-out bond strength between fiber post and root dentin.

BACKGROUND: To evaluate the push out bond strength and modes of failure of fiber post by using photodynamic therapy (PDT), Er,Cr:YSGG laser and conventional cleaning and shaping (CCS). METHODS: Sixty maxillary anterior teeth were sectioned horizontaly 2 mm incisal to the cemento-enamel junction, and root canal were prepared for post space. Tapered fiber posts were placed inside the root canal after post space was made. The fiber posts were subjected to PDT, Er,Cr:YSGG laser and CSS with 20 specimens in each group. The specimens obtained were sectioned in cervical and apical sections. A universal testing machine was used to perform the push out test and the push out bond strength was formulated by σ = C/A, expressed in mega-pascals (MPa). RESULTS: The highest mean push out bond strength was achieved by PDT group (8.08 ±â€¯2.73 MPa) and the lowest was shown by specimens in CCS group (7.45 ±â€¯1.04 MPa). ANOVA showed no statistical difference among the experimental groups (p = 0.481). In the cervical segments, the mean push-out bond strength was found to be slightly higher for all three groups compared to apical segments (P < 0.05). The independent t-tests results showed that the mean push-out bond strength values of the cervical segments were slightly higher than the apical segments in PDT, Er,Cr:YSGG and CSS groups (P < 0.05). Significant differences were observed when mean push-out bond strengths were compared for both cervical (p = 0.037) and apical (p = 0.019) segments between all the groups. Twenty-one failures were found at the interface between the adhesive and the dentin surface, 6 failures were observed at the interface between the adhesive and post, whereas 5 failures were mixed. CONCLUSION: Push-out bond strength to root canal dentin were not affected by Er,Cr:YSGG compared with conventional cleaning and shaping. However, PDT produced the smallest number of failure modes and slightly higher push-out bond strength to root dentin.