YAG Laser Group Research Articles

Comparison of Er:YAG Laser and Hand Instrumentation on the Attachment of Cultured Human Gingival Fibroblasts to Periodontally Involved Root Surfaces.

Introduction: The present study compared the effects of erbium-doped yttrium aluminium garnet (Er:YAG) laser and hand instrumentation on the attachment of human gingival fibroblast (HGF) cells to periodontally involved root surfaces. Methods: A total of 40 tooth specimens were collected and treated in four distinct groups: scaled and root planed with hand instruments, scaled with Er:YAG laser, treated with a combination of hand instruments and Er:YAG laser and non-treated control group. The attachment and proliferation rate of HGF were assessed using MTT assay and scanning electron microscope (SEM) examination was used for cell morphological evaluation. Results: The MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyl tetrazolium bromide) assay showed significant decrease in HGF cell viability in both hand instruments only and combination treated teeth specimens compared to control specimens (P<0.05), 24 hours after cell seeding. However, at time 48, the cell viability of attached cells in these 2 treated groups was almost similar to control. In contrast, at 24 and 48 hours after cell seeding, viability of attached cells was higher than control in Er:YAG laser treated only specimens (P<0.05). According to SEM study, the laser treated specimens showed more surface roughness. Conclusion: Er:YAG laser increased attachment and proliferation of HGF cells in comparison to the hand instruments method.

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

Introduction: Today, bleaching is a routine noninvasive alternative for treatment of discolored teeth. 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 their Knoop microhardness (KHN) as well as DIAGNOdent (DD) values were recorded. They were divided into 4 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 the 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 groups had a meaningful difference in reduction of DD values in comparison with the control group. Conclusion: It can be concluded that bleaching whether conventional or laser activated, does not make teeth vulnerable to develop carious lesions.

YAG Laser Vitreolysis vs Sham YAG Vitreolysis for Symptomatic Vitreous Floaters

Vitreous floaters are common and can worsen visual quality. YAG vitreolysis is an untested treatment for floaters. To evaluate YAG laser vitreolysis vs sham vitreolysis for symptomatic Weiss ring floaters from posterior vitreous detachment. This single-center, masked, sham-controlled randomized clinical trial was performed from March 25, 2015, to August 3, 2016, in 52 eyes of 52 patients (36 cases and 16 controls) treated at a private ophthalmology practice. Patients were randomly assigned to YAG laser vitreolysis or sham YAG (control). Primary 6-month outcomes were subjective change measured from 0% to 100% using a 10-point visual disturbance score, a 5-level qualitative scale, and National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25). Secondary outcomes included objective change assessed by masked grading of color fundus photography and Early Treatment Diabetic Retinopathy Study best-corrected visual acuity. Fifty-two patients (52 eyes; 17 men and 35 women; 51 white and 1 Asian) with symptomatic Weiss rings were enrolled in the study (mean [SD] age, 61.4 [8.0] years for the YAG laser group and 61.1 [6.6] years for the sham group). The YAG laser group reported greater symptomatic improvement (54%) than controls (9%) (difference, 45%; 95% CI, 25%-64%; P < .001). In the YAG laser group, the 10-point visual disturbance score improved by 3.2 vs 0.1 in the sham group (difference, -3.0; 95% CI, -4.3 to -1.7; P < .001). A total of 19 patients (53%) in the YAG laser group reported significantly or completely improved symptoms vs 0 individuals in the sham group (difference, 53%; 95% CI, 36%-69%, P < .001). Compared with sham, NEI VFQ-25 revealed improved general vision (difference, 16.3; 95% CI, 0.9-31.7; P = .04), peripheral vision (difference, 11.6; 95% CI, 0.8-22.4; P = .04), role difficulties (difference, 17.3; 95% CI, 8.0-26.6; P < .001), and dependency (difference, 5.6; 95% CI, 0.5-10.8; P = .03) among the YAG laser group. Best-corrected visual acuity changed by -0.2 letters in the YAG laser group and by -0.6 letters in sham group (difference, 0.4; 95% CI, -6.5 to 5.3; P = .94). No differences in adverse events between groups were identified. YAG laser vitreolysis subjectively improved Weiss ring-related symptoms and objectively improved Weiss ring appearance. Greater confidence in these outcomes may result from larger confirmatory studies of longer duration. clinicaltrials.gov NCT02897583.

Combined therapy for epistaxis by hereditary hemorrhagic teleangiectasia: A 3-year follow up study on 45 patients

Hereditary hemorrhagic telangiectasia (HHT) is a mutilating disease associated with the majority of patients with recurrent epistaxis episodes. The aim of this study was to present a single institution experience with patients treated for nasal epistaxis using a combination of Nd:YAG laser and argon plasma coagulation (APC) vs Nd:YAG laser alone, with a minimum follow-up of 3 years.45 patients (21 men, 24 women) aged from 15 to 84 years with the diagnosis of HHT were treated in the Department of Otolaryngology, Head and Neck Surgery in Homburg/Saar between 10/2002 and 10/2012 because of epistaxis, using a combination of Nd:YAG laser and APC or Nd:YAG laser alone. The observation period ranged from 36 to 120 months.15 patients were treated with Nd:YAG laser alone and 30 patients with combined Nd:YAG laser and APC. A revision was necessary in three patients (20%) in the Nd:YAG laser group and in nine (33.3%) patients in the combined group. The difference between revision rates after the two therapy forms was not statistically significant (p = 0.492). Bipolar coagulation was additionally applied in 33 patients. There was no statistically significant difference (p = 1.00) in revision rates between patients who were additionally treated with bipolar coagulation and those who did not receive bipolar coagulation as part of their treatment. No case of postoperative septal perforation was observed.Nd:YAG laser therapy remains an established option for treating treat epistaxis in HHT patients.

The effect of different cleaning methods on the surface and temperature of failed titanium implants: an in vitro study.

The aims of this in vitro study are to compare the efficacy of different cleaning methods in removing debris of failed implants and to detect thermal changes of the implants treated by various scaling instruments. Twenty-seven failed implants and two unused implants as control were included to this study-group 1: plastic curette (P), group 2: titanium curette (T), group 3: carbon curette (C), group 4: titanium brush (TB), group 5: Er:YAG laser (laser 1 (L1) 100mJ/pulse at 10Hz), group 6: Er:YAG laser (laser 2 (L2) 150mJ/pulse at 10Hz), group 7: Er:YAG laser (laser 3 (L3) 200mJ/pulse at 10Hz), group 8: ultrasonic scaler appropriate for titanium (US), group 9: air abrasive method (AA) + citric acid, and group 10: implantoplasty (I). The changes on the treated/untreated titanium surfaces and remnant debris were observed by scanning electron microscopy (SEM). Temperature of the implants before and after treatment was detected using a thermocouple. The use of air abrasive and citric acid combination and Er:YAG laser groups was found as the best methods for the decontamination of titanium surfaces of failed implant. When the hand instruments were compared, titanium curette was found better than both the plastic and the carbon curettes which leave plastics and carbon remnants on the titanium surface. The temperature was higher after hand instrumentation when compared to other experimental groups (p < 0.05). Within the limitations of the present in vitro model, it can be concluded that the best method for decontamination of the implant surface is the use of air abrasives and Er:YAG laser.

Reparability of giomer using different mechanical surface treatments.

BackgroundIn the repair process achieving high bond strength between the new and old resin based materials is necessary for clinical longevity. This study compared the effect of three different mechanical surface treatments (air abrasion, Nd:YAG laser and diamond bur) on the repair bond strength of giomer.Material and MethodsIn this in vitrostudy, 125 cylindrical giomer samples were used. The giomer samples were randomly assigned to 5 groups (n=25). In group 1, the samples did not undergo any surface treatment. In groups 2 to 4, the samples underwent surface treatments with air abrasion, Nd:YAG laser and a diamond bur. The samples in group 5 were prepared to measure giomer cohesive strength. Subsequently, the new giomer was bonded to the existing giomer in groups 1 to 4. Then the repair bond strength of the samples was measured. One-way ANOVA and post hoc Tukey test were used to compare the bond strength. ResultsThere were significant differences between the different surface treatments (P<0.001); the repair bond strength in the air abrasion group was significantly higher than that in the Nd:YAG laser group, in which it was significantly higher than that in the diamond bur group, which was in turn higher than that in group 1 (no surface treatment) (P<0.001). In addition, the cohesive strength of giomer was significantly higher than the repair bond strength in the 4 other study groups (P<0.001).ConclusionsOf all the surface treatments, air abrasion and Nd:YAG laser, in descending order, yielded the highest repair bond strength values, with the repair bond strength values of 60‒70% of the giomer cohesive strength. Key words:Air abrasion, bond strength, giomer, Nd:YAG laser, repair, surface treatment.

Evaluation of the Efficacy of Ablative vs. Fractional Er:YAG Laser Modes as a Treatment of Post-Burn Scars

Aim: To determine the effect of Er:YAG laser in the management of post-burn scars and to compare its effect to ablative and fractional lasers.Patients and methods: 50 patients with post-burn scars were recruited and randomly divided into 2 groups: Group I patients had ablative Er:YAG laser mode therapy and Group II patients had fractional Er:YAG laser rmode therapy. Vancouver scar score (VSS) was recorded for each group pre- and postoperatively, both groups showed an increase in the VSS and histopathological findings.Results: The obtained results showed morphological changes immediately after treatment, the skin surface displayed a white-gray frost, which on close inspection revealed a point pattern corresponding to individual laser columns done by fractional laser treatment.Conclusion: Ablative and fractional modes of Er:Yag laser can be used for treatment of post-burn hypertrophic scars. Ablative laser mode had better results than fractional laser mode as indicated by clinical assessment, VSS and changes of histopathological findings.

Carbon dioxide laser versus erbium:YAG laser in treatment of epidermal verrucous nevus: a comparative randomized clinical study

Background: A verrucous epidermal nevus (VEN) is a skin disorder that has been treated using different treatment modalities with varying results. Ablative lasers such as carbon dioxide laser (CO2) and erbium:yttrium–aluminum–garnet (Er:YAG) laser have been considered as the gold standard for the treatment of epidermal nevi.Objective: To evaluate and compare the efficacy, postoperative wound healing and side effects of pulsed CO2 laser and Er:YAG laser for the treatment of verrucous epidermal nevi.Materials and methods: Twenty patients with localized VEN were randomly divided into two groups. Group 1 was administered CO2 laser and group 2 underwent Er:YAG laser treatment. A blinded physician evaluated the photographs and dermoscopic photomicrographs for the efficacy and possible side effects. All patients received one treatment session and were followed up over a 6-month period.Results: Both lasers induced noticeable clinical improvement, but there were no significant differences between two lasers in treatment response, patient satisfaction, duration of erythema and side effects. The average time to re-epithelialization was 13.5 days with CO2 and 7.9 days with Er:YAG laser (p< .0005). No scarring was observed in Er:YAG laser group and no lesional recurrence was detected in CO2 laser group since treatment.Conclusion: Apart from re-epithelialization, both lasers showed equivalent outcomes with respect to treatment response, patient satisfaction, side effects and complications.

Influence of desensitizing procedures on adhesion of resin cements to dentin

This study evaluated the effect of two desensitizer agents with different contents and Nd:YAG laser irradiation on the shear bond strength (SBS) of adhesive resin cements to dentin. New treatment options of Nd:YAG laser irradiation and tetracalcium phosphate-containing agent applications were compared with routinely used glutaraldehyde-containing agents. One hundred and twenty human, caries-free premolars were embedded in acrylic resin blocks 2 mm below the cementoenamel junction. Buccal surfaces of the teeth were ground to expose dentin. The specimens were randomly assigned into three different surface treatments (desensitizing agents, Nd:YAG laser) and the control, then into three different adhesive resin cement applications (n = 10). Resin cements (Panavia SA cement (PA), Panavia SA cement with Clearfil Universal Bond (PACU), and Multilink N (MN)) were applied to the conditioned teeth surfaces using Teflon tubes. The specimens were thermocycled (5000 cycles, 5–55 ± 1 °C, dwell time 30 s). The SBS test was performed in all groups. The results were submitted to two-way ANOVA and Tukey HSD tests (p < .05). Further, SEM analysis was performed on the dentin surfaces. SBS values were significantly difference among the surface treatment groups and also among adhesive resin cement groups (p < .05). The specimen cemented with PA showed lower SBS values than PACU- and MN-applied specimens. The highest SBS value was obtained in the Nd:YAG laser group which was cemented with PACU cement. The lowest SBS value was obtained in the control group which was cemented with PA cement. In addition, SEM evaluation revealed that desensitizing agents and Nd:YAG laser occluded dentin tubules.

Decontamination of Anodized Implant Surface With Different Modalities for Peri-Implantitis Treatment: Lasers and Mechanical Debridement With Citric Acid.

Although oral rehabilitation with dental implants is a very promising and effective procedure, peri-implantitis is an emerging concern. Surgical and non-surgical methods have been applied to treat peri-implantitis together with various implant surface decontamination methods. However, there is no consensus concerning the most effective treatment for peri-implantitis. The aim of the present study is to evaluate the effects of erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser, photodynamic therapy (PDT), and titanium bur with and without citric acid on ligature-induced peri-implantitis around an anodized implant surface. Thirty dental implants with anodized surface (3.3 × 10 mm) were installed in the mandibles of five beagle dogs. After 3 months, peri-implantitis was induced by applying cotton ligatures subgingivally. After ligature removal (baseline), the implants were divided into the following treatment groups: 1) Er:YAG laser, 2) PDT, 3) titanium bur alone, and 4) titanium bur with citric acid. Animals were sacrificed after 3 months, and clinical, radiologic, histologic, and histomorphometric evaluations were conducted for all treatment modalities. The data were analyzed using one-way analysis of variance and Tukey test. A value of P <0.05 was considered statistically significant. The titanium bur with citric acid group exhibited statistically significantly greater improvement in vertical bone height than the Er:YAG laser group and significantly better bone-to-implant contact than the PDT group and the bur-alone group. Within the limits of the study, the combination of mechanical and chemical treatment proved to be the most effective treatment for disinfection of the anodized implant surface.

Bond strengths of brackets bonded to enamel surfaces conditioned with femtosecond and Er:YAG laser systems.

The aim of this study was to compare femtosecond and Er:YAG laser systems with regard to enamel demineralization and bracket bond strength. Human-extracted premolars were randomized to three groups (n = 17) depending on the conditioning treatment used for the buccal surfaces: 37% orthophosphoric acid, Er:YAG laser etching (MSP mode 120mJ, 10Hz, 1.2W), and femtosecond laser etching (0.4W, 800nm, 90fs/pulse, 1kHz). Metal brackets were bonded with Transbond XT to the conditioned surfaces and light cured for 20s. The samples were thermocycled (5000cycles, 5-55°C) and subjected to shear bond strength (SBS) testing using a universal testing machine. Failure types were analyzed under an optical stereomicroscope and SEM. The adhesive remnant index (ARI) was evaluated to assess residual adhesive on the enamel surface. The results revealed no significant differences in SBS between the Er:YAG laser (7.2 ± 3.3MPa) and acid etching groups (7.3 ± 2.7MPa; p < 0.05), whereas a significant difference was observed between the femtosecond laser etching group (3.3 ± 1.2MPa) and the other two groups (p < 0.01). ARI scores were significantly different among the three groups. The results of our study suggest that laser conditioning with an Er:YAG system results in successful etching, similar to that obtained with acid. The sole use of a femtosecond laser system may not provide an adequate bond strength at the bracket-enamel interface.

Structural and Morphological Changes in Human Dentin after Ablative and Subablative Er:YAG Laser Irradiation.

This study investigated the influence of Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser on microhardness, chemical composition and subsurface morphology of dentin cavity walls. Forty sound human premolars were selected and randomly assigned into four groups. Class V cavities were prepared either with an Er:YAG laser (groups 1 and 2; 15 Hz, 250 mJ for enamel, 10 Hz, 200 mJ for dentin) or with a high speed handpiece (groups 3 and 4). The specimens in groups 1 and 3 served as the control, whereas those in groups 2 and 4 were exposed to subablative laser irradiation following cavity preparation (10 Hz, 50 mJ). After bisecting the specimens, one half was subjected to microhardness assessment and the other half was evaluated by SEM-EDS analysis. Microhardness was significantly greater in the specimens prepared by both ablative and subablative laser irradiation (group 2) than that of the bur-prepared cavities (groups 3 and 4) (P < 0.05). The quantity of calcium ion was significantly greater in cavities prepared by the Er:YAG laser (groups 1 and 2) compared to that of the bur cavities (groups 3 and 4) (P < 0.05). Subablative irradiation improved microhardness and weight percentage of calcium ion in both laser and bur cavities, but the difference was not significant compared to that of the relevant control group (P > 0.05). Cavity preparation with an Er:YAG laser could be considered as an alternative to the conventional method of drilling, as it enhances the mechanical and compositional properties of lased dentin, especially when combined by subablative irradiation.

The efficacy of laser, ultrasound and self-adjustable file in removing smear layer debris from oval root canals following retreatment: A scanning electron microscopy study.

This study aims to compare the efficacy of different irrigation activation methods to remove smear layer and debris from oval-shaped root canals following retreatment. Ninety mandibular canines with oval-shaped root canals were selected. Retreatment was performed with R-Endo retreatment files. The samples were randomly divided into six groups (n = 15). Groups were assigned according to agitation technique: R-Endo with classic irrigation, with self-adjustable file, with passive ultrasonic irrigation, R-Endo + Er:YAG, R-Endo + PIPS and R-Endo + Nd:YAG. Compared with the classic irrigation (R-Endo + CI) group, all other groups were more successful in reducing smear layer and debris (P < 0.05). The least amount of residual smear layer and debris was detected in the Er:YAG laser group (P < 0.05). Additional use of different agitation methods contributes to removal of debris and smear layer following root canal filling removal with rotary instruments; however, none of the techniques tested render root canal walls completely free of smear layer or debris.

Effect of erosive challenge and Nd:YAG laser irradiation on bond strength of adhesive systems to dentin

PurposeTo evaluate the effect of Nd:YAG laser irradiation and erosive challenge on bond strength of two adhesive systems to dentin. MethodsTwenty bovine incisors were cut and grounded to obtain eighty slabs of flat dentin. Specimens were allocated into eight groups, based on: adhesive system—a two-step etch-and-rinse and a two-step self-etch; laser irradiation—Nd:YAG (1W/10Hz) or control (no laser irradiation); and erosive challenge after restorative procedure—presence or absence of erosive challenge. Nd:YAG laser groups were submitted to laser irradiation before the restorative procedure. Blocks of composite resin were built up on the bonded surfaces with a Southern Dental Industries device to perform shear bond strength (SBS) test. After, each specimen of erosive challenge, groups were subjected to immersion in Sprite Zero® (20ml/2h/24°C/under agitation). The SBS test (0.5mm/min) was performed after 24h of water storage at 37°C. Failure mode was evaluated with a stereomicroscope (X400). Data were analyzed with three-way ANOVA and Tukey’s post hoc tests (α=0.05). ResultsThe etch-and-rinse adhesive system presented higher bond strength values than self-etch adhesive. Laser irradiation increased the bond strengths values when erosive challenge was present. The predominant failure mode observed was adhesive. ConclusionsThe irradiation of Nd:YAG laser positively influences the bond strength values when erosive challenges are present. Moreover, the etch-and-rinse adhesive system is a better option to be used in dentin in this clinical condition.

Microleakage of Self-Etch Adhesive System in Class V Cavities Prepared by Using Er:YAG Laser with Different Pulse Modes.

In vitro studies evaluated cementum surface morphology and microleakage of three different energy density parameters of Erbium: Yttrium Aluminum Garnet (Er:YAG) laser compared with diamond bur preparation on class V cavities with self-etch adhesive system and composite resin restoration. Standard class V cavities were prepared at cervical area below the cementoenamel junction (CEJ) in 80 extracted premolars, by using a diamond bur on the buccal surface. All teeth were randomly allocated into four groups: Group 1, diamond bur; Group 2, Er:YAG 50 mJ/15 Hz, 3.77 J/cm(2); Group 3, Er:YAG 75 mJ/15 Hz, 5.65 J/cm(2); and Group 4, Er:YAG 100 mJ/15 Hz, 7.53 J/cm(2). Five cavities from each group were evaluated by scanning electron microscopy (SEM). The 15 remaining cavities from each group were restored with self-etch adhesive and nano-hybrid composite. After thermocycling, all sample teeth were immersed in 0.2% methylene blue dye and sectioned buccolingually. Statistics were analyzed using the one way ANOVA and Mann-Whitney U tests with Bonferroni correction. The morphology showed micro-irregularities in the cementum surface of the laser group with the absence of a smear layer. The microstructure characteristics were increased surface roughness followed by increasing laser energy transmission. The Er:YAG laser groups were statistically significant, with less microleakage than the diamond bur group (p<0.05). There was statistically significant difference between the occlusal and gingival microleakage in all the groups (p<0.05). When the laser groups were compared, the lowest microleakage was achieved with energy density at 3.77 J/cm(2) on the occlusal and gingival cementum margin, which showed less microleakage than at energy densities of 5.65 and 7.53 J/cm(2) with Er:YAG laser. These observations indicate that the micro-irregularities of the cementum surface could facilitate the formation of a hybridization zone with a self-etch adhesive system. Therefore, the microleakage of Er:YAG laser irradiation was significantly decreased compared with diamond bur cavities.

A randomized controlled trial of peeling and aspiration of Elschnig pearls and neodymium: yttrium-aluminium-garnet laser capsulotomy.

To compare surgical peeling and aspiration and neodymium yttrium garnet laser capsulotomy for pearl form of posterior capsule opacification (PCO). A prospective, randomized, double blind, study was done at Rotary Eye Hospital, Maranda, Palampur, India, Santosh Medical College Hospital, Ghaziabad, India and Laser Eye Clinic, Noida India. Consecutive patients with pearl form of PCO following surgery, phacoemulsification, manual small incision cataract surgery and conventional extracapsular cataract extraction (ECCE) for age related cataract, were randomized to have peeling and aspiration or neodymium yttrium garnet laser capsulotomy. Corrected distance visual acuity (CDVA), intra-operative and post-operative complications were compared. A total of 634 patients participated in the study, and 314 (49.5%) patients were randomized to surgical peeling and aspiration group and 320 (50.5%) to the Nd:YAG laser group. The mean pre-procedural logMAR CDVA in peeling and neodymium: yttrium-aluminium-garnet (Nd:YAG) laser group was 0.80±0.25 and 0.86±0.22, respectively. The mean final CDVA in peeling group (0.22±0.23) was comparable to Nd:YAG group (0.24±0.28; t test, P=0.240). There was a significant improvement in vision after both the procedures (P<0.001). A slightly higher percentage of patients in Nd:YAG laser group (283/88.3%) than in peeling group (262/83.4%) had a CDVA of 0.5 (20/63) or better at 9mo (P<0.001). On the contrary, patients having CDVA worse than 1.00 (20/200) was also significantly higher in Nd:YAG laser group as compared to peeling group (25/7.7% vs 15/4.7%, respectively). On application of ANCOVA, there was less than 0.001% risk that PCO thickness and total laser energy had no effect on rate of complications in Nd:YAG laser group and less than 0.001 % risk that PCO thickness had no effect on complications in peeling group respectively. Sum of square analysis suggests that in the Nd:YAG laser group, thick PCO had a stronger impact on complications (Fischer test probability, Pr<0.0001) than thin PCO and total laser energy (Fischer test probability, Pr<0.002), respectively; similarly, in peeling group, thick PCO and preoperative vision had a stronger effect on complications than thin PCO, respectively (Fischer test probability, Pr<0.001).The rate of complications like uveitis (P=0.527) and cystoid macular edema (P=0.068), did not differ significantly between both the groups. However, intraocular pressure spikes (P=0.046) and retinal detachment (P<0.001) were significantly higher in Nd:YAG laser group as compared to peeling group. Retinal detachment was more common in patients having degenerative myopia (7/87.5%, P<0.001). Recurrence of pearls was the most common cause of reduction of vision in the peeling group (24/7.6%, P<0.001). There is no alternative to Nd:YAG laser capsulotomy for fibrous subtype of PCO. For pearl form of PCO, both techniques are comparable with regard to visual outcomes. Nd:YAG laser capsulotomy has a higher incidence of IOP spikes and retinal detachment whereas recurrence of pearls may occur after successful peeling and aspiration. When posterior capsulotomy is needed in patients with retinal degenerations, retinopathies and pre-existing retinal breaks, the clinician should be cautious about increased risks of possible complications of Nd:YAG laser capsulotomy.

Caries removal in deciduous teeth using an Er:YAG laser: a randomized split-mouth clinical trial.

The aim of the present clinical randomized split-mouth study was to evaluate the effectiveness and efficiency of an Er:YAG laser for caries removal in primary molars, microbiological dentin analysis, and clinical restorations after 1 year in 29 children. The children's teeth were randomized into two groups: (I) an Er:YAG laser group and (II) a bur preparation group. The efficiency of the treatments (the time necessary for the removal of carious tissue) was evaluated based on the time spent on caries removal in the deciduous molars. The effectiveness (caries removal capacity) of the caries removal was determined by means of a blind test in which the examiner performed a tactile and visual examination of the dentin. Microbiological analysis was performed by counting the Streptococcus mutans and Lactobacillus sp in the remaining dentin. Clinical analysis of restorations was performed using the USPHS method in combination with photographs of restored teeth, 7 days after the restorative procedure and again after 1 year. All cavities were restored with the Adper Single Bond 2/Filtek Z350 system. The obtained data were analyzed with a significance level of 5 %. The Er:YAG laser was less effective and had the same efficacy as bur preparation during caries removal at the pulpal wall of deciduous molars. In the surrounding walls, bur preparation was the more effective method. Regardless of the method employed, the affected dentin in the pulpal wall had similar amounts of S. mutans and Lactobacillus sp. The restorations were clinically accepted by the USPHS method over a 1-year period. It can be concluded that caries removal with an Er:YAG laser has no influence on the clinical behavior of restorations. Irradiation with an Er:YAG laser is appropriate for caries removal in primary teeth.

Comparison of Nd:YAG and Diode Laser Irradiation During Intracoronal Bleaching with Sodium Perborate: Color and Raman Spectroscopy Analysis

The aim of this study was to evaluate the color and enamel structure changes after intracoronal bleaching with sodium perborate under neodymium:yttrium-aluminum-garnet (Nd:YAG) and diode laser irradiation. Although some studies investigated the efficacy of laser irradiation during intracoronal bleaching, no study has been conducted to investigate the changes in both color and enamel structure during intracoronal bleaching with laser irradiation. Thirty-six extracted mandibular incisors were used. The root canals were prepared and filled with AH Plus and gutta-percha. Baseline color values and Raman spectra were obtained from all samples. The samples were randomly divided into three groups as follows: group 1, intracoronal bleaching with sodium perborate plus NdYAG laser irradiation; group 2, intracoronal bleaching with sodium perborate plus diode laser irradiation; and group 3, intracoronal bleaching with sodium perborate without any laser irradiation. Following the bleaching procedures, the final baseline color values and Raman spectra were obtained. The baseline and final values were statistically analyzed. Statistical analyses were performed with SPSS 18.0 software using Anova and the Kruskal-Wallis test. There was a significant difference between the Nd:YAG laser and control groups (p<0.05). There was no significant difference between the diode laser group and the control group, or the diode laser group and the Nd:YAG laser group. There was no significant difference among all groups in terms of Raman relative intensity (RRI) and fluorescence intensity (FI) percentage values (p>0.05). Laser application, especially Nd:YAG laser irradiation, was able to increase the efficacy of intracoronal bleaching with sodium perborate. Laser irradiation significantly increased the bleaching efficacy without any changes in the enamel surface structure.

Comparison of Smear Layer Removal Using the Nd:YAG Laser, Ultrasound, ProTaper Universal System, and CanalBrush Methods: An In Vitro Study

IntroductionThe aim of this study was to compare the efficacy of the Nd:YAG laser, ultrasound, the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland), and the CanalBrush (Coltene Whaledent, Langenau, Germany) methods for the removal of the smear layer from the apical third of root canals. MethodsFifty distal root canals from extracted human mandibular first molars were instrumented up to ProTaper Universal F5 and divided randomly into 5 groups (n = 10) according to the following final irrigation agitation techniques: no agitation (control), ProTaper Universal file, ultrasound, CanalBrush, and Nd:YAG laser. Specimens were observed under a scanning electron microscope. The presence of the smear layer was evaluated using a 3-grade scoring system. The data were analyzed with Cohen kappa, Kruskal-Wallis, and Mann-Whitney U tests. A level of significance of .05 was adopted. ResultsThe ultrasound group performed significantly better than the rest of the groups; 56.6% of the specimens revealed no smear layer, 44.4% showed the presence of a moderate smear layer, and no heavy smear layers were observed. In the Nd:YAG laser group, 30% of the specimens presented with no smear layer, 70% showed the presence of a moderate smear layer, and no heavy smear layers were observed. In contrast, a heavy smear layer was observed on the surfaces of the root canals in the CanalBrush (23.4%), ProTaper Universal (13.4%), and control (86.6%) groups. Statistically significant differences were observed (P < .05). ConclusionsNone of the agitation methods completely removed the smear layer. However, the ultrasound method performed significantly better followed by the Nd:YAG laser, the CanalBrush, and the ProTaper Universal system. Agitation of the irrigant improved smear layer removal in the apical third of the canal.

Comparison of different irrigation activation techniques on smear layer removal: an in vitro study.

The purpose of this study was to evaluate the efficiency of different irrigation activation techniques on smear layer removal. About 80 single-rooted human maxillary central teeth were decoronated to a standardized length.The samples were prepared by using ProTaper system to size F4 and divided into eight equal groups (n = 10) according to the final irrigation activation technique; distilled water was used as an irrigant in Group 1. The other groups were treated with 2.5% NaOCl and 17% EDTA, respectively. Conventional syringe irrigation (CSI) was used in Group 2. Irrigation solutions were activated using passive ultrasonic irrigation (PUI, Group 3), EndoVac apical negative pressure (ANP, Group 4), diode laser (Group 5), Nd:YAG laser (Group 6), Er:YAG laser (Group 7), and Er:YAG laser using with photon-induced photoacoustic streaming (PIPS™, Group 8). Teeth were split longitudinally and subjected to scanning electron microscope (SEM). PIPS showed the best removal of smear layer when compared with PUI, ANP, Nd:YAG, and Er:YAG, but the difference was not statistically significant (P > 0.05). Smear layer scores obtained with PIPS technique were statistically significant different from those of obtained with control, CSI and diode laser groups (P < 0.05). All experimental irrigation techniques except ANP and diode laser removed smear layer more effectively at the coronal and middle levels compared to the apical level (P < 0.05). Irrigation activated/delivered techniques except diode laser have a positive effect on removing of smear layer.