Erbium-doped Yttrium Aluminum Garnet Laser Research Articles

Effect of Er: YAG laser therapy in non-surgical periodontal treatment: an umbrella review.

The current umbrella review aimed to summarize the effect of erbium-doped yttrium aluminum garnet (Er: YAG) laser adjunct with the conventional non-surgical periodontal treatment which was evidenced from available systematic reviews. An extensive literature search was piloted by two independent reviewers in the PubMed, Scopus, Science Direct, and Google Scholar databases. The search was limited to the English language from 2011 to 2023 years. The methodological quality of systematic reviews 2 (AMSTAR 2) guideline was followed to evaluate the risk of bias for the selected studies. Cohen's kappa statistic was implemented to evaluate the level of agreement to assess the risk of bias in the selected studies. A total of 472 studies were initially identified. After removing the duplicates and screening, a total of four studies were selected for the current overview. Based on the quality assessment tool, each study scored as high, moderate, low, and critically low-quality study following AMSTAR 2 tool. Inter-rater reliability by Cohen's Kappa statistics showed near-perfect agreement (0.95) between the two reviewers. Even though weak evidence of effectiveness was observed for Er: YAG laser application in non-surgical periodontal treatment, the clinical benefits are still lacking.

Effect of different surface conditioning methods and low pH solutions on the shear bond strength of orthodontic brackets to newly introduced CAD/CAM materials

AimTo evaluate the shear bond strength (SBS) of ceramic and metallic orthodontic brackets bonded to lithium disilicate ceramics or hybrid ceramics and subjected to different surface conditioning treatments. Materials and methodsIn total, 300 specimens were fabricated from GC LiSi (lithium disilicate) and GC Cerasmart (hybrid) ceramic blocks. The specimens were divided into four groups according to the following surface treatments: hydrofluoric acid (HF); sandblasting with 50 μm aluminum oxide; Monobond Etch and Prime; and erbium-doped yttrium aluminum garnet (Er-YAG) laser. Metal (Victory Series) and ceramic (Clarity) brackets were bonded using an orthodontic adhesive resin (Transbond XT; 3M Unitek, CA, USA). The specimens were then stored in three different mediums (artificial saliva, mouth rinse, and gastric juice) and thermocycled. An SBS test was performed after 1 week. The surface morphology was examined after the conditioning treatments using a scanning electron microscope. Data were analyzed using analysis of variance, t-test, and Duncan test. ResultsThe SBS data revealed that the type of computer-aided design/computer-aided manufacturing (CAD/CAM) block and surface conditioning method significantly affected the SBS. The highest SBS was recorded (10.112 MPa) for the HF-treated hybrid ceramic blocks stored in the saliva medium, while the lowest SBS (1.862 MPa) was reported for the Er-YAG laser-treated lithium disilicate ceramic blocks stored in the gastric juice medium. GC Cerasmart exhibited better bond strength than that of GC LiSi; however, no significant difference was observed between the ceramic and metal brackets. ConclusionThe CAD/CAM material, surface conditioning method, and medium affect the SBS.

Comparison of a Novel Modality of Erbium-Doped Yttrium Aluminum Garnet Laser-Activated Irrigation and Ultrasonic Irrigation against Mature Enterococcus faecalis Biofilm-An In Vitro Study.

In this in vitro study, we aimed to evaluate and compare the antibacterial efficacy of a novel erbium-doped yttrium aluminum garnet laser modality, shock wave enhanced emission of photoacoustic streaming (SWEEPS), ultrasonically activated irrigation (UAI), and single needle irrigation (SNI) against old bacterial biofilm. A two-week-old Enterococcus faecalis biofilm was cultivated on transversal dentinal discs made from the middle third of the roots of single-rooted, single-canal premolars. Biofilm growth was confirmed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The dentine samples were randomly distributed into three experimental groups and one control group based on the irrigation protocol used: Group 1, SWEEPS; Group 2, UAI; and Group 3, SNI. The root canals were irrigated with a 3% sodium hypochlorite solution. Antibacterial efficacy was evaluated quantitatively through bacterial culture and qualitatively through CLSM and SEM. Both SWEEPS and UAI demonstrated a statistically significant reduction in Enterococcus faecalis colony-forming units (CFUs) (p < 0.001), while SNI did not show a statistically significant reduction (p = 0.553). No significant difference was observed between the efficacy of SWEEPS and UAI (p > 0.05). The SWEEPS and UAI techniques were equally effective in eliminating mature E. faecalis biofilm.

Effect of resin cement viscosities and surface roughness on shear bond strength of conditioned polymer infiltrated ceramic network

BackgroundHybrid ceramics bonding with the dentinal substrate is crucial for clinical success and longevity. To enhance adhesion, the surface of ceramic restorations is modified through various conditioning techniques AimEffect of Different Surface Conditioners Erbium-doped yttrium aluminum garnet (ER: YAG) laser and Low-level laser therapy (LLLT) activated Methylene blue (MB) on the surface roughness (Ra) and shear bond strength (SBS) of Polymer infiltrating ceramic network (PICN) discs bonded using different viscosity resin cement before and after thermal aging. Material and MethodsOne hundred and fifty human central incisors and one hundred and fifty-three PICN discs were prepared. PICN discs were randomly allocated into three groups based on the surface conditioning(n = 51) Group 1:10 % HF acid-S, Group 2: LLLT (MB), and Group 3: Er: YAG laser. Following conditioning Ra scores of ten samples were performed. Surface topography of samples was performed using a scanning electron microscope (SEM). Bonding of forty PICN discs from each conditioning group was performed with high (A) or low viscosity (B) dual-curing resin cement (n = 20 each). Each subgroup was divided into two cohorts and subjected to varying storage conditions. The SBS test and failure mode analysis were performed using a universal testing machine and stereomicroscope. Descriptive statistics of SBS and Ra for each group were analyzed using ANOVA and Tukey post hoc tests. HF acid-S attained the highest Ra scores. ResultsGroup 1A (HF-S+HIGH) samples achieved the highest SBS values at baseline. Group 3A, on the other hand, displayed the lowest bond score (Er: YAG laser+HIGH) after thermal aging. Intergroup comparison analysis at baseline unveiled that Group 1A and Group 1B (HF(S) + LOW) displayed no significant difference in their bond strength scores (p>0.05). Following artificial aging, it was observed that Group 2A (LLLT (MB) + HIGH) and Group 3A (Er:YAG laser + HIGH) ) presented comparable SBS(p > 0.05). Thermal aging decreased SBS significantly in all groups. PICN conditioned with HF-S results in high surface roughness. ConclusionPICN conditioned with HF acid with silane and bonded with low-viscosity resin cement to the dentinal substrate is preferable. Aging influences SBS.

Shedding Light on Acne Scars: A Comprehensive Review of CO2 vs. Erbium-Doped Yttrium Aluminium Garnet (Er:YAG) Laser Therapy.

Acne scars pose a significant cosmetic concern and can have a profound impact on individuals' self-esteem and quality of life. Laser therapy has emerged as a promising treatment modality for improving the appearance of acne scars by promoting collagen remodeling and tissue regeneration. This comprehensive review compares two commonly used laser modalities, CO2 and erbium-doped yttrium aluminum garnet (Er:YAG), focusing on their mechanisms of action, efficacy, safety profiles, and patient outcomes. While CO2 lasers offer deeper tissue penetration and the potential for more significant improvement in severe acne scars, Er:YAG lasers provide a gentler approach with a lower risk of post-inflammatory hyperpigmentation. Recommendations for clinical practice include tailoring treatment approaches to individual patient characteristics, educating patients about treatment expectations and post-treatment care, considering combination therapies for enhanced outcomes, and implementing regular follow-up care. Areas for further research include long-term outcome studies, investigation of laser therapy in ethnically diverse populations, exploration of combination therapies, and evaluation of emerging laser technologies. This review aims to provide clinicians and patients with valuable insights to inform treatment decisions and optimize outcomes in managing acne scars.

Effects of Two Remineralizing Agents in Combination with Er:YAG and CO2 Laser Irradiation on Microhardness of Demineralized Enamel: A Preliminary In Vitro Study.

Objectives: This study assessed the effects of two remineralizing agents namely MI Paste Plus containing casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACFP) and Remin Pro containing hydroxyapatite, fluoride and xylitol (HFX) with/without erbium-doped yttrium aluminium garnet (Er:YAG) and CO2 laser irradiation on demineralized enamel microhardness. Materials and Methods: In this in vitro study, 70 sound human premolars were mesiodistally sectioned, demineralized at a pH of 4.6 for 8 hours, and randomly divided into 7 remineralization groups (n=10): of (I) MI Paste Plus (CPP-ACFP), (II) Remin Pro (HFX), (III) MI Paste Plus+CO2 laser (0.7 W power, 50 Hz), (IV) Remin Pro+CO2 laser, (V) MI Paste Plus+Er:YAG laser (1 W power, 10 Hz), (VI) Remin Pro+Er:YAG laser, and (VII) negative control. The Vickers hardness number of specimens was then measured. The groups were compared by one-way ANOVA and Tukey's test (α=0.05). Results: The mean microhardness was 319.8±49.9, 325.3±44.6, 359.4±35.7, 296.4±33.7, 319.9±58.1, 358.9±28.4, and 240.0±41.6 kg/mm2 in groups 1 to 7, respectively. The difference in microhardness was significant among the groups (P<0.0001). Pairwise comparisons revealed significant differences in microhardness between all groups (P≤0.03) except between groups 1 and 2, 1 and 5, 2 and 5, and 3 and 6 (P>0.05). Conclusion: Both Remin Pro (containing HFX) and MI Paste Plus (containing CPP-ACFP) can cause enamel remineralization. MI Paste Plus+CO2 laser irradiation and Remin Pro+Er:YAG laser irradiation were significantly more effective than the application of each remineralizing agent alone.

Er:YAG Laser Alleviates Inflammaging in Diabetes-Associated Periodontitis via Activation CTBP1-AS2/miR-155/SIRT1 Axis.

Periodontitis is a significant health concern for individuals with diabetes mellitus (DM), characterized by inflammation and periodontium loss. Hyperglycaemia in DM exacerbates susceptibility to periodontitis by inducing inflammaging in the host immune system. The use of erbium-doped yttrium-aluminum-garnet laser (ErL) in periodontitis treatment has gained attention, but its impact on diabetic-associated periodontitis (DP) and underlying mechanisms remain unclear. In this study, we simulated DP by exposing human periodontal ligament fibroblasts (PDLFs) to advanced glycation end products (AGEs) and lipopolysaccharides from P. gingivalis (Pg-LPS). Subsequently, we evaluated the impact of ErL on the cells' wound healing and assessed their inflammaging markers. ErL treatment promoted wound healing and suppressed inflammaging activities, including cell senescence, IL-6 secretion, and p65 phosphorylation. Moreover, the laser-targeted cells were observed to have upregulated expression of CTBP1-AS2, which, when overexpressed, enhanced wound healing ability and repressed inflammaging. Moreover, bioinformatic analysis revealed that CTBP1-AS2 acted as a sponge for miR155 and upregulated SIRT1. In conclusion, ErL demonstrated the ability to improve wound healing and mitigate inflammaging in diabetic periodontal tissue through the CTBP1-AS2/miR-155/SIRT1 axis. Targeting this axis could represent a promising therapeutic approach for preventing periodontitis in individuals with DM.

In vitro effect of Er: YAG laser irradiation in caries cavity preparation on biobehaviors of adjacent human dental pulp cells in the pulp chamber.

The erbium-doped yttrium aluminum garnet (Er: YAG) laser has been successfully applied in caries removal; however, little is known about proper parameters of Er: YAG laser on different conditions of caries removal, especially the influence of Er: YAG irradiation on human dental pulp cells (hDPCs). Here, we tested the effects of Er: YAG laser at different output energy levels (100, 200, 300, 400, and 500 mJ) on biobehaviors of hDPCs. To simulate clinical deep caries conditions, hDPCs were cultured on the pulpal side of 500-μm-thick dentin disks in an in vitro pulp chamber model. Temperature change, structural change, and ablation depth of dentin disk were also recorded. The findings suggested that the biological behaviors of hDPCs are strongly correlated with the energy output of the Er: YAG laser. Er: YAG laser irradiation at 100 mJ may be proper and safe for deep caries removal since it would not cause any adverse effect on hDPCs biobehaviors.

Er:YAG laser settings for debonding zirconia restorations: An in vitro study

This in vitro study aimed to determine the optimal frequency and energy settings for debonding zirconia restorations using an erbium-doped yttrium aluminum garnet (Er:YAG) laser. A total of 200 zirconia specimens (5 mm × 5 mm × 1.5 mm) were fabricated from two types of materials: (1) 3 mol% yttria oxide stabilized tetragonal zirconia polycrystalline (3Y-TZP) and (2) 5 mol% yttria oxide stabilized tetragonal zirconia polycrystalline (5Y-TZP). The zirconia specimens were bonded to dentin using resin cement (RelyX Ultimate, 3 M) and divided into 20 groups based on their laser treatments (n = 5). Er:YAG laser treatment was applied at various frequencies (10 Hz and 20 Hz) and energies (80 mJ, 100 mJ, 120 mJ, 140 mJ, 160 mJ, 180 mJ, 200 mJ, 220 mJ, 240 mJ, and 260 mJ). The time required to debond the specimens and the temperature changes that dentin underwent during the laser treatment were recorded. The surface morphologies of the debonded dentin and zirconia specimens were observed using scanning electron microscopy (SEM). Additional zirconia specimens were fabricated for 4-point flexural strength testing and surface roughness measurements. Statistical analyses were conducted using three-way analysis of variance (ANOVA) and Student–Newman–Keuls (SNK)-q tests (α = 0.05). The debonding time of each specimen varied between 4.8 and 160.4 s, with an average value of 59.2 s. The dentin temperature change for each specimen ranged from 2.3 to 3.6 °C, with an average value of 2.7 °C. The debonding time was significantly influenced by the zirconia material type and laser energy, but it was not affected by the laser frequency. Among the specimens, those made of 3Y-TZP needed significantly more time for debonding than 5Y-TZP. The optimal energies were 220 mJ for 3Y-TZP and 200 mJ for 5Y-TZP. The laser frequency, laser energy, and type of zirconia material had no effect on the dentin temperature change. Additionally, no surface alternations were observed on the dentin or zirconia materials after laser treatment. The surface roughness and flexural strength of the zirconia materials remained unchanged after laser treatment. In summary, Er:YAG laser treatment effectively and safely removes zirconia restorations without impacting their mechanical properties, with a safe temperature change of less than 5.6 °C. The optimum frequency and energy settings for debonding 3Y-TZP and 5Y-TZP restorations were found to be 10/20 Hz and 220 mJ and 10/20 Hz and 200 mJ, respectively.

Comparative Study of the Surgical Excision of Impacted Mandibular Third Molars Using Surgical Burs and an Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) Laser.

Background The use of lasers has increased in the field of dentistry in recent years. However, in the field of oral and maxillofacial surgery, the use of lasers has been largely restricted to soft tissue, and less focus is placed on the use of lasers for hard tissues. Aim The present study aimed to comparatively evaluate the efficacy of a erbium-doped yttrium aluminum garnet (Er:YAG) laser for cutting the bone while removing the impacted mandibular third molar with the use of a surgical bur. Methods The study assessed 80 subjects undergoing removal of impacted mandibular third molars. The subjects were recruited from the Department of Oral and Maxillofacial Surgery, Luxmi Bai Institute of Dental Sciences and Hospital, Patiala, Punjab, India. They were randomly divided into two groups, each consisting of 40 subjects. Group I used an Er:YAGlaser to remove the bone, while Group II used a surgical bur. Assessments and comparisons were made for complications, wound healing, trismus, edema, bleeding, and pain. Results The study examined the efficacy of the Er:YAG laserfor cutting the bone and extracting the impacted mandibular third molars using a surgical bur in two groups of 80 patients each. When the laser was used in place of a surgical bur, Group I patients experienced less edema, bleeding, and discomfort; nevertheless, the difference was not statistically significant. Time taken by laser for bone cutting was significantly higher compared to the surgical bur. In Group I (laser), trismus existed for a longer time. For mouth opening, the preoperative mouth opening was comparable in the two groups with p = 0.87. Conclusion Pain, hemorrhage, and edema were lesser, and the time required for bone cutting was substantially longer in the laser group. Apart from these, laser-assisted intra-oral bone cutting should be preferred because of its less invasive nature, simpler procedure, and simpler osteotomy when compared to traditional surgical burs and also in anxiety-prone patients.

How We Do It: Erbium-Doped Yttrium Aluminum Garnet Laser for the Treatment of Postsurgical Trapdoor Deformity.

How We Do It: Erbium-Doped Yttrium Aluminum Garnet Laser for the Treatment of Postsurgical Trapdoor Deformity.

Geometric Cuts by an Autonomous Laser Osteotome Increase Stability in Mandibular Reconstruction With Free Fibula Grafts: A Cadaver Study

BackgroundNon-union and plate exposure represent a major complication after mandibular reconstruction with free fibula flaps. These drawbacks may be resolved by geometric osteotomies increasing inter-segmental bone contact area and stability. PurposeThe aim of this study was to compare inter-segmental bone contact and stability of geometric osteotomies to straight osteotomies in mandibular reconstructions with free fibula grafts performed by robot-guided erbium-doped yttrium aluminum garnet laser osteotomy. Study design, setting, sampleThis cadaveric in-vitro study was performed on fresh frozen human skull and fibula specimens. CT-scans of all specimens were performed for virtual planning of mandibular resections and three-segment fibula reconstructions. The virtual planning was implemented in a Cold Ablation Robot-guided Laser Osteotome. Predictor/exposure/independent variableFor predictor variables straight and geometric puzzle-shaped osteotomies were designed at resection of the mandible and corresponding fibula reconstruction. Main outcome variablesThe primary outcome variable was the stability of the reconstructed mandible investigated by shearing tests. Moreover, secondary outcome variables were the duration of the laser osteotomies, the contact surface area and the accuracy of the reconstruction, both evaluated on post-surgical CT-scans. CovariatesCovariables were not applicable AnalysisData were reported as mean values (± standard deviation) and were statistically analyzed using an independent-sample t-test on a significance level of α = 0.05. Root mean square deviation was tested for accuracy. Results8 skulls and 16 fibula specimens were used for the study. 112 successful laser osteotomies (96 straight and 16 geometrical) could be performed. Geometric osteotomies increased stability (110.2±36.2 N vs. 37.9±20.1N, p<0.001) compared to straight osteotomies. Geometric osteotomy of the fibula took longer than straight osteotomies (10.9±5.1min vs. 5.9±2.2min, p=0.028), but could provide larger contact surface (431.2±148.5mm2 vs. 226.1±50.8mm2, p=0.04).Heat map analysis revealed a mean deviation between preoperational planning and post-reconstructive CT-scan of -0.8 ±2.4mm and a root mean square deviation of 2,51mm. ConclusionMandibular resection and reconstruction by fibula grafts can accurately be performed by a cold ablation robot-guided laser osteotome without need for cutting guides. Osteotomy planning with geometric cuts offers higher stability and an increased bone contact area which may enhance healing of the reconstructed mandible.

Spatially modulated erbium YAG laser as a treatment for diabetic ulcer.

Diabetic ulcers are a significant healthcare challenge, capable of diminishing quality of life, lengthening hospitalisation stay, and incurring substantial costs for patients and healthcare systems. Erbium-doped yttrium-aluminum-garnet (Er-YAG) laser has been evolving as a prospective intervention for addressing wounds of various aetiologies. Despite this, the literature remains limited in appraising the effectiveness of laser therapy specifically in diabetic wounds. This study investigates the impact of employing a spatially modulated Er-YAG laser as a therapeutic approach for treating diabetic ulcers. In a single-arm study conducted from November 2017 to April 2023, patients with hard-to-heal ulcers were treated in a two-step approach of wound debridement using Er-YAG laser for ablation and biostimulation through deep tissue resonance using RecoSMA (Multiline laser system, LINLINE MS, Latvia) laser technology. Ulcers received weekly laser treatment, together with routine care until healing occurred and were then followed up to observe any recurrence. The primary outcome measure was wound closure; the secondary outcome measures were time to closure, and the number of laser treatments required. Data related to sociodemographic details, size and number of diabetic ulcers, and number of sessions related to laser treatment were collected using a predesigned, pretested questionnaire before initiating the treatment. A total of 59 patients attending the clinic during the study period with diabetic ulcers were included in the study. The mean wound surface area at baseline was 25.7cm2 (median: 12cm2). The average number of sessions of laser treatment required was 4.41, ranging from 1-11. The size of the ulcer reduced with each session of laser treatment. The diabetic ulcers healed completely at the end of the treatment, indicating the effectiveness of the Er-YAG/RecoSMA two-step approach. Spatially modulated erbium YAG laser is effective as a therapeutic approach for treating diabetic ulcers.

Oral microbial colonization on titanium and polyetheretherketone dental implant healing abutments: An in vitro and in vivo study

Although polyetheretherketone (PEEK) implant healing abutments have become popular because of their esthetic, mechanical, and chemical properties, studies analyzing oral polymicrobial adhesion to PEEK abutments are lacking. The purpose of this in vitro and in vivo study was to evaluate oral microbial adhesion and colonization on titanium (Ti) and PEEK healing abutments. Ti (N=35) and PEEK substrates (N=35) were evaluated in vitro in terms of the initial adhesion (1 hour) or biofilm accumulation (48 hours) of Candida albicans and a polymicrobial inoculum using stimulated human saliva to mimic a diverse oral microbiome. Surface decontamination ability was evaluated after 24 hours of in vitro biofilm formation after exposure to an erbium-doped yttrium aluminum garnet (Er:YAG) laser. Conventional and flowable composite resin veneering on PEEK was also tested for microbial adhesion. In addition, an in vivo model with 3 healthy volunteers was conducted by using a palatal appliance containing the tested materials (3 or 4 specimens of each material per appliance) for 2 days to evaluate the effect of substrate on the microbial profile. Biofilms were evaluated by live cell counts and scanning electron microscopy images, and the microbial profile by Checkerboard deoxyribonucleic acid (DNA)-DNA hybridization. The t test and Mann-Whitney test were used to compare the groups (α=.05). PEEK and Ti materials showed similar fungal adhesion (P>.05). Although the PEEK surface limited the initial in vitro polymicrobial adhesion (approximately 2 times less) compared with Ti (P=.040), after 48 hours of biofilm accumulation, the microbial load was statistically similar (P=.209). Er:YAG laser decontamination was more effective on PEEK than on Ti surfaces, reducing approximately 11 times more microbial accumulation (P=.019). Both composite resins tested showed similar microbial adhesion (1 hour). In vivo, the PEEK material showed reduced levels of 6 bacterial species (P<.05), including the putative pathogen Treponema denticola. Although PEEK and Ti had similar bacterial and fungus biofilm attachment and accumulation, PEEK promoted a host-compatible microbial profile with a significantly reduced T. denticola load.

Analysis of Predictive Factors for Return to Sports in Female Athletes With Stress Urinary Incontinence.

Introduction This study aimed to identify predictive factors for successful return to sports among elite female athletes (EFAs) experiencing stress urinary incontinence (SUI). We used machine learning to analyze these predictors. Methods This study was conducted at Yokosuka Urogynecology and Urology Clinic, located in Yokosuka City, Kanagawa, Japan. A total of 153 EFAs with postpartum SUI were included in this retrospective cohort study. Information regarding the frequency of pelvic floor muscle training (PFMT), treatment approaches, rates of return to sports after one year, and one-hour pad test (1HrPadtest) at three months were collected. Results At three months, 26.8% of the EFAs improved in SUI; after one year, 28.1% returned to their respective sports successfully. The equation for predicting return to sports (logit(p)) involved several factors: (a) serum total testosterone, (b) PFMT frequency per week, (c) 1HrPadtest at three months, and (d) vaginal erbium-doped yttrium aluminum garnet laser (VEL) + urethral EL (UEL) treatment. The equation was as follows: -126 - 0.07276a + 25.98b - 1.947c - 25.32d, with a logit(p) cutoff point at 0.5. The optimal cutoff values and the four influential factors were determined through a receiver operating characteristic (ROC) analysis and the random forest model, respectively. Conclusions For EFAs with severe SUI to successfully return to their sports activities, the PFMT frequency was paramount. Patients who exhibited unsatisfactory results in the 1HrPadtest at the three-month mark benefited from the VEL+UEL treatment. Serum total testosterone proved to be an effective discerning criterion.

Evaluation of the Erbium-doped Yttrium Aluminum Garnet Laser and the Conventional Method on Pain Perception and Anxiety Level in Children during Caries Removal: A Randomized Split-mouth Study.

To assess and compare children's anxiety level and pain perception during cavity preparation using an erbium-doped yttrium aluminum garnet (Er:YAG) laser vs traditional rotational treatment. A randomized, controlled, split-mouth clinical trial was carried out in 35 healthy children with 70 carious primary molars. Teeth were divided equally into two groups according to the method of treatment. A bur was used to prepare the cavity in one quadrant, while an Er:YAG laser was used to prepare the cavity in the other quadrant. Anxiety was assessed using Venham's dental anxiety scale and a fingertip pulse oximeter. The pain was assessed using the Wong-Baker Face Pain Rating Scale, and the number of local anesthesia (LA) needed during both procedures was also considered. The mean age was 9.4 ± 1.29. Males accounted for 51.4% of the participants. There were no statistically significant variations in pulse rate at the baseline between Er:YAG laser and the conventional treatments. The mean pulse rate was higher during the conventional intervention than during the laser intervention; this difference was statistically significant vs the baseline pulse rate. The mean pulse rate with the conventional method was significantly higher during and after cavity formation than with the laser method. The Er:YAG laser and the conventional groups showed statistically significant differences in the Venham's and Wong-Baker scores. The scores of both scales were much higher in the conventional group. The number of participants who requested LA during the conventional technique was significantly higher than during the laser procedure. Using Er:YAG lasers to remove caries produces minimal pain and anxiety and reduces the requirement for LA. During cavity preparation, the Er:YAG laser helps children stay calm. Abdrabuh RE, El Meligy OAES, Felemban OM, et al. Evaluation of the Erbium-doped Yttrium Aluminum Garnet Laser and the Conventional Method on Pain Perception and Anxiety Level in Children during Caries Removal: A Randomized Split-mouth Study. Int J Clin Pediatr Dent 2023;16(S-1):S39-S44.

Optimized Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) Laser Parameters for the Removal of Dental Ceramic Restorations.

The use of lasers for debonding adhesively luted ceramic restorations is a rather recent oral laser application in dentistry. The removal of all-ceramic restorations in the mouth can often be a troublesome task. A novel method for the debonding of ceramic restorations without damaging the restorations is Er:YAG laser irradiation. The aim of this study was to evaluate the Er:YAG laser for debonding procedures of different dental ceramics and to identify appropriate laser settings. Lithium disilicate, zirconium-reinforced lithium silicate, feldspatic ceramic, and zirconium dioxide were investigated. Ten ceramic rectangular-shaped specimens with 1 and 2 mm thickness were produced from each material. All specimens were irradiated with four different power settings 1.5; 2.5; 3.5; 4.5 W, pulse duration 50 μs, laser repetition rate 10 Hz, time of irradiation 10 s. The transmitted energy was measured with a powermeter. Additionally the suitability of the Er:YAG laser to remove the adhesively bonded ceramic and the time until loss of retention was evaluated. The transmission rate for 1 and 2 mm platelets was determined for zirconium-reinforced lithium silicate at 54.6%/35.6%, lithium disilicate at 53.2%/35.7%, zirconium dioxide at 40.6%/32.4%, and for the feldspathic ceramic at 19.4%/10.1%. For zirconium-reinforced lithium silicate and zirconium dioxide 2.5 W (250 mJ/10 Hz) was an appropriate energy level for effective debonding. Whereas for lithium disilicate and for feldspathic ceramic, 4.5 W (450 mJ/10 Hz) is required for efficient debonding. There are differences regarding transmission rates between ceramic types for the Er:YAG laser light and additionally depending on the type of ceramic different energy settings should be used for adequate debonding. Based on our in-vitro experiments we recommend 2.5 W for zirconium-reinforced lithium silicate and zirconium dioxide and 4.5 W for lithium disilicate and feldspatic ceramic. Transmission rates of different ceramic types and varying influences of thicknesses and bonding materials should be considered to adjust the laser parameters during laser debonding of adhesively luted all-ceramic restorations.

Cleaning Efficiency of Different Irrigation Techniques in Simulated Severely Curved Complex Root Canal Systems

IntroductionTo compare the biofilm-mimicking hydrogel removal efficiency of laser-activated irrigation (LAI) with five other irrigation techniques in simulated curved root canals with lateral canals. MethodsThree-dimensional–printed root canal models (60°-curvature, radius 5 mm; dimension 25/.06) with a total length of 20 mm and lateral canals in all directions at 2, 5, and 8 mm (diameter 0.2 mm) from the apex were filled with a colored biofilm-mimicking hydrogel. The following protocols (each 3 × 20 seconds continuous irrigation with distilled water 3 ml/20 seconds; n = 20) were carried out: conventional needle irrigation; manual agitation ([MA], gutta-percha point 25/.06); EndoActivator (=sonically-activated irrigation EndoActivator, 25/.04); EDDY (=sonically-activated irrigation EDDY [SAI-E]; 25/.04); ultrasonically-activated irrigation and LAI (Erbium-doped Yttrium Aluminum Garnet laser; P400FL tip at canal entrance; 25 pps, 50 mJ, 300 μs). Standardized photos were taken with a microscope and the removal of the hydrogel was determined as a percentage for the entire system, the main canal and the lateral canals. Statistical analysis was performed using analysis of variance and Scheffé test (P = .05). ResultsLAI (89.3% ± 5.9%) showed the greatest hydrogel removal followed by SAI-E (65.5% ± 3.3%) and ultrasonically-activated irrigation (59.1% ± 4.7%), with significant differences between these groups (P < .05). Needle irrigation, MA, and sonically-activated irrigation EndoActivator performed equally (P > .05) and obtained the significantly lowest values (P < .05). LAI and SAI-E showed the significantly best hydrogel removal from the main canal (P < .05). At all three levels, LAI removed significantly more hydrogel from the lateral canals than all other techniques (P < .05). ConclusionsLAI was superior to other techniques in both the entire system and the lateral canals in removing the hydrogel. SAI-E achieved comparable results in the main canal.

A study of the objective benefits and safety of Er-YAG laser in the treatment of genitourinary syndrome of menopause

The aim of this study is to evaluate changes in vaginal pH and epithelium maturation after erbium-doped yttrium aluminum garnet (Er-YAG) laser treatment, and to assess its safety and efficacy on the symptoms of genitourinary syndrome of menopause (GSM). This was a retrospective study conducted between November 2019 and April 2022 and included 32 women diagnosed with GSM who had not benefitted from lubrication treatment and could not or would not use estrogen. Patients received three sessions of Er- YAG laser. All patient data before and after treatment were obtained from computer records. Vaginal maturation index (VMI), maturation value (MV) and vaginal pH values of the patients before and after laser treatment were compared. We also evaluated post-procedural complications and symptoms. Mean age was 59.72 ± 5.66years. After laser therapy, there was a significant decrease in vaginal pH (p < 0.001) and the proportion of parabasal cells in VMI (p < 0.001), while there was a significant increase in MV (p < 0.001) and the proportion of superficial cells in VMI (p < 0.001). In 84.4% of the patients, GSM-related symptoms regressed completely or decreased to a tolerable level. Patients in which symptoms disappeared completely had significantly lower mean age (p = 0.002) and duration of menopause (p = 0.009). The laser procedure resulted in complications including mucosal injury in 5 (15.6%) patients (all recovered spontaneously) and vaginal burning sensation in 2 (6.3%) patients. Vaginal Er-YAG laser treatment may be a safe and effective alternative treatment method in a population of women with GSM who do not want to or cannot use estrogen therapy.

Comparison of the shear rebond strength of zirconia brackets treated with different Er:YAG laser energies.

This study aimed to identify the optimal technological parameters for rebonding zirconia brackets treated using an erbium-doped yttrium aluminum garnet (Er:YAG) laser. Er:YAG lasers with varying energies were compared with the flaming and sandblasting treatment methods. Detached zirconia brackets were treated and evaluated for shear rebond strength, bracket bottom-plate morphology, position, and depth of microleakage. They were then treated for rebonding using flaming, sandblasting, or an Er:YAG laser set at 250-mJ, 300-mJ, 350-mJ energy. Their shear rebond strength were measured using microforce tester. The topography of the treated bottom plates were observed using scanning electron microscopy. A confocal laser scanning microscope was used to measure the depth of the joint and gingival-side microleakage at the bracket-adhesive (B-A) and enamel-adhesive interfaces. With 300 mJ Er:YAG laser treatment, the detached zirconia brackets can obtain good rebonding strength and minimize the shape change of bracket bottom plates; the adhesion of the B-A interface is better than other methods.