Surface Treatment by Different Parameters of Erbium:Yttrium–Aluminum–Garnet (Er:YAG) Laser: Scanning Electron Microscope (SEM) Evaluation

Introduction: This study aimed to assess the Scanning Electron Microscope (SEM) analysis of tooth surface irradiated by erbium:yttrium–aluminum–garnet (Er:YAG) laser with various parameters.Methods: Number of 25 extracted human third molars free of caries were used in this study. The teeth were put into 5 groups for laser irradiation as follows: group 1 (power: 0.5 W, Energy: 50 mJ); group 2 (power: 1 W, Energy: 100 mJ); group 3 (power: 1.5 W, Energy: 150 mJ); group 4 (power: 2 W, Energy: 200 mJ); group 5 (power: 2.5 W, Energy: 250 mJ). All samples were prepared by repetition rate of 10 Hz and duration of 230 μs, using a non-contact handpiece at a distance of 4 mm. Then, the samples were prepared for SEM examination.Results: SEM evaluation of every 25 samples, treated by Er:YAG, showed that all groups had exposed dentinal tubules without any melted area or cracks.Conclusion: In this study we used SEM to investigate ablated dentine with different parameters of Er:YAG laser energy. Our findings support these conclusions. All powers of laser below 3 W are proper for ablation, and make no cracks

Evaluation of the Effect of Different Laser Activated Bleaching Methods on Enamel Susceptibility to Caries; An In Vitro Model

Introduction: Today bleaching is a routine noninvasive alternative for treatment of discolored teeth. The concern has been raised whether or not oxidizing reaction during this process, might endanger integrity of the teeth and raise the risk of caries formation. The aim of this study was to determine whether conventional or laser activated bleaching predispose teeth to develop caries or not.Methods:Sixty human molars were mounted on acrylic cylinders and Knoop microhardness (KHN) and DIAGNOdent (DD) values of them were recorded. They were divided into four experimental groups; G1)conventional bleaching with 40% Hydrogen peroxide gel G2) Diode laser assisted bleaching with same gel. G3)Nd;YAG laser assisted bleaching with the same gel. G4)control group. After bleaching, all samples were subjected to a three day pH cycling regimen and then, KHN and DD values were measured.Results:All groups had significant reduction in KHN values. . It seems that there is no statistically meaningful difference between changes in enamel microhardness of sample groups and all groups have changed in a similar amount. Reduction of DD scores were significant in Diode laser and conventional groups, however changes in Nd:YAG laser and control groups were not significant. Changes in DD values have followed a similar pattern among groups, except in G1-G4 and G2-G4 couples. Conventional and Diode laser group had a meaningful difference in reduction of DD values in comparison with control group.Conclusion:It can be concluded that bleaching whether conventional or laser activated method, does not make teeth vulnerable to develop carious lesions

Laser Treatment of Peri-Implantitis: A Literature Review

Peri-implantitis is a state defined as an inflammatory reaction around osseointegrated implants, leading to progressive loss of supporting bone. Various treatment methods are suggested in the treatment of peri-implantitis and clinicians have to choose a method over a large number of treatment protocols. Lasers have shown promising therapeutic effect in treatment of peri-implantitis. However, some controversies have been found in clinical outcomes after using lasers. Therefore, we aimed to review the current literature over the past ten years for the use of lasers in treatment of peri-implantitis, via the Pubmed electronic database of the US National Library of Medicine. Fifteen human studies were reviewed. Er:YAG (Erbium-Doped Yttrium Aluminum Garnet), CO2(Carbon Dioxide Laser) and Diode lasers were used. Despite inconsistencies and disharmonies among studies in terms of study design, positive treatment outcomes were obvious among the majority of them. However, short period of follow-ups and poor control of plaque index, as a critical confounding factor, were the major problems which these studies suffered from. It seems that one session laser therapy is not adequate for achieving optimal clinical outcome. Further studies with longer periods of follow-ups, intense control of plaque index, and various sessions of laser treatments are needed to clearly illustrate the clinical privilege of laser therapy

Comparative Efficacy of Topical Curcumin and Triamcinolone for Oral Lichen Planus: A Randomized, Controlled Clinical Trial

Objectives: Lichen planus (LP) is a chronic inflammatory mucocutaneous disease. Its treatment is often symptomatic and includes topical and systemic corticosteroids. Although corticosteroid therapy is usually successful, it has side effects and thus, an alternative treatment is favorable. The aim of this study was to compare the efficacy of topical curcumin and triamcinolone for treatment of oral lichen planus (OLP).  Materials and Methods: In this study, 50 patients (36 women and 14 men) in the age range of 38 to 73 years with OLP were randomly divided into two groups. Each group received 0.1% triamcinolone or 5% curcumin oral paste three times a day for four weeks. Assessment of the appearance score and severity of pain was done at baseline and at the end of two and four weeks and recorded in the patients’ questionnaires. The data were analyzed by SPSS 17 software, using the Mann-Whitney and Spearman’s tests. Results: With respect to pain reduction, nine patients (36%) in the curcumin group and eight patients (32%) in the triamcinolone group showed complete remission. With respect to the appearance score, one patient (4%) in each group showed complete remission. No statistically significant difference was noted between the two groups. Conclusion: Application of curcumin is suggested for treatment of OLP because of its desirable anti-inflammatory effects and insignificant side effects

The method and device for thermoregulation and optimization of dental material′s quality and working time

Introduction: No one can cast a shadow of doubt on the fact that temperature is a key element in dentistry. Temperature control enable dentists in a variety of clinical fields to perform more convenient. Frozen slab is a known method for manipulating temperature before mixing cements. But lack of precise temperature and infection control is bolded. Clinical innovation: The present apparatus determines a method for temperature control in routine dentistry tasks; namely restorative dentistry, prosthesis and even injections. This device is capable of whether heating or cooling materials using low voltage electricity. Peltier or thermoelectric effect is the mechanism behind this device. As operator sets a temperature, device would provide it via metal pads arranged on it in seconds. Discussion: Other common methods used in dentistry have some issues regarding power usage, infection control, size and etc. However, this device is small, cost effective, simple to use and has fast action. Infection control can be actively be maintained with it. This device is a promising alternative for this purpose. Present manuscript summarizes device properties and its potential utilities in dentistry

Effect of different endodontic sealers on push-out bond strength of fiber posts

the increasing demand for fiber-reinforced composite (FRC) posts, their bonding to root canals is still subject to debate. Endodontic sealers may affect the bond strength between fiber posts and root canal dentin. Aim: To compare the effects of different sealers on fiber post bond strength. Methods: Sixty teeth were divided into 4 groups according to obturation method: GI, gutta-percha without any sealers; GII, gutta-percha and AH26 resin-based sealer; GIII, RealSeal point and RealSeal resin-based sealer, GIV, Guttaflow. Fiber posts were cemented into root canals. Specimens were sectioned, and the bond strength was measured in the middle area. The failure mode was evaluated. Data were analyzed by one-way ANOVA and post hoc test. Results: The highest bond strength was observed in the control group (2.95±1.12), and the least was in the Guttaflow group (1.15±0.78). There was a significant difference between bond strengths of the control and Guttaflow groups and between AH26 and Guttaflow groups (p<0.05). The failure mode was mainly adhesive between dentin and resin cement in all groups. Conclusions: Sealers may have a negative effect on the bond strength of fiber posts to root canal dentin

Effect of Low Level Laser Therapy on Pain Reduction After Midpalatal Expansion in Rats

Objectives: The purpose of this experimental study was to evaluate the efficacy of low level laser therapy (LLLT) for pain reduction after midpalatal expansion in rats.   Materials and Methods: Sixty male Sprague six-week old rats weighing 180±10g were divided into seven groups (two experimental groups of 24 rats and one control group of 12 rats). The experimental groups were subjected to expansion with or without LLLT. The health status of each rat was monitored starting seven days prior to the experiment and evaluated by regular body weight monitoring during the study period. Diode laser with 810nm wavelength and 100 mw output power was used. Laser therapy and body weight monitoring were performed on days 0, 2, 4, 6, 8, 10, 12 and 14. The data were analyzed by One-way repeated measures ANOVA. Results: The body weight of the experimental groups significantly decreased in the first two days because of the pain and difficult nutrition with the new appliance. Within the next two days, the body weight of all rats increased but this increase was significantly higher in the irradiated compared to the non-irradiated group. This significant improvement continued until day 14 and then between days 14 and 30 the rats gained weight similarly in the irradiated and control groups. Conclusion: The study results showed that laser irradiated group continued to gain weight easier than the control group. This may be due to more efficient pain control due to laser irradiation after midpalatal expansion

Utilizing Edentulous Ridge as Autogenous Block Graft for Buccal Contouring Horizontal Ridge Augmentation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/172922/1/cap10138_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/172922/2/cap10138.pd

Laser- assisted regenerative surgical therapy for peri- implantitis: A randomized controlled clinical trial

BackgroundDifferent surgical approaches have been proposed to treat peri- implantitis defects with limited effectiveness and predictability. Laser has been proposed as an effective tool to assist in bacterial decontamination and modulating peri- implant tissue inflammation. The aim of this pilot clinical trial was to evaluate the adjunctive benefits of Er:YAG laser irradiation for regenerative surgical therapy of peri- implantitis- associated osseous defects.MethodsTwenty- four patients diagnosed with peri- implantitis with a radiographic infrabony defect were randomized into two groups. Both test and control groups received the following treatment: open flap mechanical debridement, supracrestal implantoplasty, bone grafting using a mixture of human allograft with demineralized bone matrix human allograft putty, and then covered with acellular dermal matrix membrane. The only difference in the test group was the adjunctive use of Er:YAG laser to modulate and remove inflammatory tissue as well as to decontaminate the implant surface. Clinical assessments, including pocket depth (PD), clinical attachment level (CAL), and gingival index (GI) were performed by calibrated masked examiners for up to 6 months following surgery. Standardized radiographs were also taken to evaluate linear bone gain and defect bone fill. Student t- tests were used to analyze those clinical parameters.ResultsBoth groups showed significant reductions in PD, GI, and CAL gain overtime. The test group demonstrated significantly higher PD reductions at the site level compared to the control group (2.65 ± 2.14 versus 1.85 ± 1.71 mm; test versus control, P = 0.014). There were no statistical differences found in CAL gain (1.90 ± 2.28 versus 1.47 ± 1.76 mm; test versus control), GI reduction (- 1.14 ± 1.15 versus - 1.04 ± 0.89; test versus control), radiographic linear bone gain (1.27 ± 1.14 versus 1.08 ± 1.04 mm; test versus control) or proportional defect size reduction (- 24.46 ± 19.00% versus - 15.19 ± 23.56%; test versus control). There was a positive trend for test patients on PD reduction and CAL gain found in narrow infrabony defects. Major membrane exposure negatively impaired the overall treatment outcome of CAL gain (2.47 ± 1.84 versus 1.03 ± 1.48 mm; no/minor versus major exposure, P = 0.051) and PD reduction in the test group (- 3.63 ± 2.11 versus - 1.66 ± 1.26 mm, P = 0.049).ConclusionThis pilot study indicated using laser irradiation during peri- implantitis regenerative therapy may aid in better probing PD reduction. Nonetheless, a larger sample size and longer follow- up is needed to confirm if Er:YAG laser irradiation provides additional clinical benefits for peri- implantitis regenerative therapy (Clinicaltrials.gov: NCT03127228)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/167069/1/jper10622_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/167069/2/jper10622.pd