Assessment of microleakage of class V composite resin restoration following erbium-doped Yttrium Aluminum Garnet (Er:YAG) laser conditioning and acid etching with two different bonding systems

The use of laser for cavity preparation or conditioning of dentin and enamel surfaces as an alternative for dental tissue acid-etch have increased in recent years. The aim of this in vitro study was to compare microleakage at enamel-composite and dentincomposite interfaces following Erbium-Doped Yttrium Aluminum Garnet [Er:YAG] laser conditioning or acid-etching of enamel and dentin, hybridized with different bonding systems. Class V cavities were prepared on the lingual and buccal surfaces of 50 recently extracted intact human posterior teeth with occlusal margin in the enamel and gingival margin in the dentin. The cavities were randomly assigned to five groups: group1:conditioned with laser [Energy=120mJ, Frequency=10Hz, Pulse duration=100 micro s for Enamel and Energy=80mJ, Frequency=10Hz, Pulse duration=100 micro s for Dentin] + Optibond FL, group2:conditioned with laser + etching with 35% phosphoric acid + Optibond FL, group3:conditioned with laser + Clearfil SE Bond, group 4 [control]:acid etched with 35% phosphoric acid + Optibond FL, group 5 [control]: Clearfil SE Bond. All cavities were restored using Point 4 composite resin. All samples were stored in distilled water at 37°C for 24 h, then were thermocycled for 500 cycles and immersed in 50% silver nitrate solution for 24 h. The teeth were sectioned bucco-lingually to evaluate the dye penetration. Kruskal-Wallis and Mann-Whitney tests were used for statistical analysis. In occlusal margins, the least microleakage showed in groups 2, 4 and 5. The maximum microleakage was observed in group 3 [P=0.009]. In gingival margins, the least microleakage was recorded in group2, while the most microleakage was found in group 5 [P=0.001]. Differences between 5 study groups were statistically significant [P<0.05]. The microleakage scores were higher at the gingival margins. The use of the Er:YAG laser for conditioning with different dentin adhesive systems influenced the marginal sealing of composite resin restorations

Scanning electron microscope comparative evaluation of feldspathic porcelain surfaces under irradiation by different powers of neodymium-doped Yttrium Aluminium Garnet [Nd:YAG] laser

Recent use of lasers for porcelain surface treatment for adhesion of brackets to restorations has not only showed some promising results, but is also accompanied with less undesirable effects among other advantages. The purpose of this study is the comparative electron microscope evaluation of feldspathic porcelain surfaces under irradiation by Neodymium-Doped Yttrium Aluminium Garnet [Nd:YAG] with different powers [0.75, 1.5 and 2W] via the acid etching with hydrofluoric acid [HF] technique. The glazed porcelain samples were obtained by duplicating labial surfaces of maxillary central incisor teeth. The specimens were randomly treated by 4 different methods. Group1 was etched with hydrofluoric acid 9.6%. Samples in group 2 to 4 were also irradiated by Nd:YAG laser with different powers: 0.75, 1.5 and 2W. Then the samples were prepared for evaluation by scanning electron microscope [SEM]. Etching quality from a porosity point of view was similar for group2 and HF group. Laser with power of 0.75W has little potential to create mechanical porosity. In regard of the results of this study, it is possible to benefit from Nd:YAG laser with appropriate parameters for surface conditioning

Effect of low level laser application at the end of surgery to reduce pain after tonsillectomy in adults

Tonsillectomy is among commonest otorhinolaryngologic surgeries. Many methods have been used to control post surgical pain, but despite it, pain is still one of the problems related to this operation. Recently, due to the non invasiveness of low level lasers, this modality has attracted attention. The purpose of this study is to evaluate the effects of low level laser irradiation at the end of surgery on reduction of pain after tonsillectomy in adults. In a clinical trial, 60 adult patients, candidates for tonsillectomy were randomly assigned to two groups, A and B, and both groups were anesthetized similarly by the same technique. At the end of surgery, in the case group, the tonsils' bed were irradiated by infrared laser with 980nm wavelength, 100Hz, 4J/cm[2] from the infra mandibular angle. In the control group, the tonsils' bed had laser therapy with a turned off probe. Following laser treatment, the patients were reversed and extubated and consciousness achieved, pain and odynophagia were assessed at 2, 4, 6, 8, 12 and 24h post surgery based on visual analog scale for pain [VAS] and analgesic consumption. In the laser group frequency of patients with pain sensation in each evaluated hour was lower than in the control group. The amount of pain decrease and analgesic consumption reduction was significantly higher in patients who received laser [P=0.01]. Based on the results of this study, use of low level lasers is effective in reducing tonsillectomy post surgical pain in adults

Clinical approach of laser application in different aspects of pediatric dentistry

The application of laser in dentistry is considered as a favorable technique for patients due to its many advantages compare to other current methods. One of the main goals in pediatric dentistry is to provide the treatment as comfortable as possible without any risks for the care. Laser is being used in different pediatric dental conditions including caries detection, caries removal and cavity preparation, soft tissue surgery and in low level laser therapy applications. The application of current common lasers in dentistry resulted in less stress and fear in patients during dental procedures, also leading to more conservative non-invasive methods for soft and hard tissues with minimal discomfort and bleeding

Comparative evaluation of the effects of 5% sodium fluoride varnish and neodymium-doped yttrium aluminium garnet [nd:yag] laser and their combined application on dentin hypersensitivity treatment

Dentin hypersensitivity is one of the most common complications that patients suffer from after periodontal therapies. So far many investigators have used different types of fluoride and laser for treatment of this complication. The aim of this study was to evaluate the effects of 5% sodium fluoride varnish and [Neodymium-Doped Yttrium Aluminium Garnet] Nd:YAG laser and their combined application on dentin hypersensitivity treatment. The study is a prospective interventional clinical trial. We selected a group of 9 patients with a total of 60 hypersensitive teeth. Each patient had at least 4 hypersensitive teeth. These 4 teeth were randomly placed in 4 different groups. Group1 didn't receive any treatment. Group2 was treated with 5% sodium fluoride varnish [A Durashield Company product]. Group3 was irradiated with Nd: YAG laser [1w, 20Hz, 120s]. Group4 was treated by 5% sodium fluoride varnish and Nd: YAG laser combined [same parameters as group3]. The assessment of the patients' pain was done with cold air blast test [CAB] and visual analyzing scale [VAS] after stimulation using a probe and cold air. Patients' pain was assessed before and just after treatment, and also 2 hours, 1 week and 2 weeks after treatment. For the assessment of pulp vitality we used the electric pulp test [EPT] at each session. SPSS 11.5 was used to process the results obtained. For the CAB and VAS changes in different groups, two-way repeated-measures ANOVA as well as Post-Hoc-Tukey tests were used. For the comparison of the different treatment groups at each session, one-way ANOVA, Post-Hoc-Tukey and or Mann-Whitney and Kruskal-Wallis tests were used. VAS and CAB scores didn't show any significant difference between different groups before treatment. Analysis of results obtained with two-way ANOVA test for repeated measures showed significant statistical differences for CAB and VAS scores in all groups between before and after treatment except for CAB score in control group. In the comparison of the fluoride varnish group and laser group alone with fluoride varnish-laser combined group using VAS and CAB scores, we found a significant difference. But we didn't find any significant difference for the comparison between the varnish fluoride group and the laser group using the same score. The use of 5% sodium fluoride varnish and laser for treatment of dentin hypersensitivity is accompanied by a placebo effect. Although it appears that, if we omit the placebo effect, we had an improvement in all 3 treatment groups. But this improvement was more obvious for the treatment group4 [fluoride -laser] compared to other groups.

Low level laser therapy in management of complications after intra oral surgeries

One of the basic purposes in dental treatment is providing a painless treatment for patients. This purpose may be achieved by the application of laser in dentistry. Low-level laser therapy [LLLT] is an internationally accepted title for biomodulation with low-level lasers which we use to achieve ideal therapeutic effects. Low-level laser therapy is a painless, reproducible, non-invasive, and without need of anesthesia treatment which is used to treat a variety of pain syndromes, injuries, wounds, fractures, neurological conditions and pathologies. Laser therapy works on the principle of inducing a biological response through energy transfer. The parameters that used in laser therapy determine the effective depth of penetration. We can mention anti-inflammatory effects, stimulation of wound healing, stimulation of immune system, increase of blood flow and activation of vasodilatation, increase of cellular metabolism and analgesic effects as advantages of the application of this type of laser. The aim of this review study was to evaluate the effect of low-level laser therapy after oral surgeries

Antimicrobial photodynamic therapy as an adjunctive modality in the treatment of chronic periodontitis

Due to penetration of pathogenic bacteria into the periodontal tissues in moderate to severe periodontitis, the mechanical methods are not sufficient in these cases. Therefore, administration of local/systemic antibiotic is recommended following mechanical root debridement. However, side effects of antibiotics such as microbial resistance and patient allergy led to development of alternative methods. One of the suggested methods is the antimicrobial photodynamic therapy [aPDT]. aPDT is a local non invasive treatment modality without the side effects caused by antibiotics. The aim of this study was to collect the clinical articles related to the application of aPDT in the treatment of chronic periodontitis. In order to find related clinical articles, a search of PubMed, Google Scholar and Science Direct until 2012 was performed. A total of 11 articles were found. In 7 of the 11 articles, the assessment of aPDT led to a significant improvement in the clinical attachment and probing depth. In 4 studies, there was no difference between the scaling and root planing [SRP] and adjunctive application of aPDT. aPDT in most cases resulted in less gingival bleeding compare to SRP alone. Furthermore, its application in multiple doses was more effective in comparison to a single dose treatment. It appears that aPDT is effective as an adjunctive therapy compared to conventional non_surgical treatment alone, and is recommended in multiple doses in order to achieve more appropriate results