Clinical efficacy of the Er:YAG laser treatment on hypersensitive dentin

Dentinal Tubule Occluding Efficacy Of Er: YAG Laser And Universal Adhesive Loaded With Nano-Carbonated Apatite

ER:YAG laser and experimental resin-based dental adhesive loaded with functionalized carbonated apatite filler were used in this study to evaluate the dentin interaction in terms of penetration and occlusion of the dentinal tubules aiding in the control of dentin hypersensitivity (DH). Spheroidal Carbonated apatite nanoparticles (N-CAP), with an average size of 20±5 nm diameter, were synthesized, characterized, and incorporated in a universal adhesive "All Bond Universal, Bisco, USA", in (2% weight) concentration. Er:YAG laser "Lightwalker, FOTONA, EU" was adjusted to an energy output of 40mJ/ pulse and pulse repetition of 10 Hz for 10 seconds. Dentin specimens were prepared from the buccal surface of 75 extracted sound human molars. The specimens were randomly divided into five groups (n=15) according to the surface treatment: Group (L): Laser only; Group (LB): Laser in combination with adhesive; Group (LBN): Laser in combination with adhesive loaded with N-CAP; Group (B): adhesive only; and Group (BN): adhesive loaded with N-CAP. Depth of penetration and occlusion of the dentinal tubules were assessed using Environmental Scanning Electron Microscope Examination (ESEM). One-way ANOVA was used to compare groups, followed by a pairwise test for multiple comparisons (α=0.05). Groups (LB), and (LBN) showed the highest mean of dentinal tubules' penetration, with a non-significant difference between them. In contrast, the specimens treated with laser only (L) showed the most minor penetration. The employment of ER-YAG laser irradiation with the adhesive loaded with N-CAP was evaluated to be effective in penetrating and occluding the opened dentinal tubules.

Comparative Evaluation of Er: YAG Laser, Diode Laser, and Novamin Technology for Dentinal Tubule Occlusion: An In-Vitro Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray Analysis (EDX) Study

BACKGROUND

Dentinal hypersensitivity is a brief and painful oral condition that is characterized by an abrupt shooting sensation. Stimulation occurs when hot, cold, sweet, or sour food comes into contact with exposed dentinal tubules. The present study used a scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDX) to investigate the efficacy of Er: YAG, 810 nm diode LASER, and NovaMin Technology in obstructing dentinal tubules.

MATERIAL AND METHODS

We extracted the outer layers of 30 human teeth to expose the tubules and then treated the surfaces with 17% ethylenediaminetetraacetic acid (EDTA) to create an etched effect. Three cohorts were created from the portions. Group A was subjected to the application of Erbium:Yttrium-Aluminum-Garnet (Er: YAG) laser with a power output of 2W in the non-contact mode for 1 minute. Group B was subjected to the application of an 810nm diode laser with a power output of 1W in continuous mode for 30 seconds. Group C was subjected to the application of NovaMin paste, which contains a 927 ppm fluoride content. Following the therapy, occluded dentinal tubules were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) for both quantitative and qualitative examination. The data analysis was conducted using a one-way analysis of variance (ANOVA) and Tukey's test, with a significance threshold of 0.05.

RESULTS

The average percentages of complete blockage of dentinal tubules in Groups A, B, and C were evaluated using the number of entirely unobstructed dentinal tubules at magnifications of 2000X (F = 3.05, p = 0.064), 5000X (F = 5.33, p = 0.011), and 10000X (F = 8.63, p = 0.001). The count of partially open dentinal tubules seen at magnifications of 2000X, 5000X, and 10000X was F = 10.15 (P < 0.001), F = 5.97 (p = 0.007), and F = 2.12 (p = 0.140) accordingly.

CONCLUSION

NovaMin technology has demonstrated more effectiveness in blocking dentinal tubules compared to 810nm diodes and Er: YAG lasers.

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.

A Comparative Analysis of the Occluding Effects on Dentinal Tubules With the Use of Er:YAG Laser and a Commercially Available Desensitizing Agent: An In Vitro Scanning Electron Microscopic Study

Objective This in vitro scanning electron microscopic (SEM) study aimed to compare the effect of Er:YAG laser and a commercially launched dental product namely 8% arginine-calcium carbonate on exposed dentinal tubules. Materials and methods A total of 120 tooth samples prepared from healthy maxillary first premolars extracted due to orthodontic reasons were grouped randomly into four groups of 30 samples each - Group I: control group (C); Group II: laser group (LG); Group III: toothpaste group (TP) and Group IV: laser + toothpaste group (LT). The samples in Group II-IV were treated with the respective test agents and were placed under SEM to study the changes in the dentinal tubule number and diameter. The data obtained from SEM were then subjected to statistical analysis using an unpaired t-test. Results The unpaired t-test revealed extreme statistical differences in means between the test and the control groups and among the test groups (p<0.0001). The results we obtained within the scope of this study showed that both the Er:YAG laser (1.3 W, 100 mJ, 3 Hz, 60 s twice) and dentifrice containing 8% arginine-calcium carbonate as the main ingredient can significantly reduce the number and diameter of the open dentinal tubules. Conclusion Our findings have demonstrated that both the 8% arginine-calcium carbonate technology and Er:YAG laser successfully reduced the number and diameter of the open dentinal tubules and hence can be promising agents to deal with dentinal hypersensitivity in future clinical studies.

Effect of Various Lasers With or Without Systemp.desensitizer on Dentine Tubules: An In Vitro Scanning Electron Microscopy Analysis

Objective: The current study was carried out to evaluate the effects of laser and Systemp.desensitizer therapy. Further, scanning electron microscopy (SEM) was used to determine the effects of individual or combined desensitizers on human dentinal tubules. Background: The most common clinical condition that makes people uncomfortable is dentin hypersensitivity (DH). Both lasers and drugs that reduce sensitivity have been used to treat DH. Materials and methods: A total of 100 dentinal samples were taken from newly extracted third molars (affected) and divided into 10 groups (A to J), that is, control (A); Systemp.desensitizer (B); diode laser (980 nm) (C); Nd:YAG laser (D); Er:YAG laser (E); Er,Cr:YSGG laser (F); Systemp.desensitizer + diode laser (G); Systemp.desensitizer + Nd:YAG laser (H); Systemp.desensitizer + Er:YAG laser (I); and Systemp.desensitizer + Er,Cr:YSGG laser (J). SEM was used to evaluate the dentinal specimens in each group (longitudinal and transverse portions), and then images of each sample were captured (20 images/sample). In addition, the number of open dentinal tubules was counted and then the occlusion depth in dentinal tubules was measured. Mann-Whitney and Kruskal-Wallis tests were employed to analyze the obtained data. Results: All treatment procedures and protocols were effective in blocking dentinal tubules (p < 0.05). Compared with the other groups, dentinal tubules in the laser and laser combination therapy groups were significantly obstructed (p < 0.05). Diode and Nd:YAG lasers with or without Systemp.desensitizer showed significantly more tubule occlusion and greater sealing depth than Er:YAG and Er,Cr:YSGG lasers with or without Systemp.desensitizer (p < 0.05). Conclusions: In summary, lasers alone or in combination can play a significant role in occluding the dentinal tubules. However, combining the diode or Nd:YAG laser with Systemp.desensitizers is a more effective treatment strategy and may have immediate and long-lasting effects.

Laser therapy for dentinal hypersensitivity

BACKGROUND

Dentinal hypersensitivity is characterized by short, sharp pain from exposed dentine that occurs in response to external stimuli such as cold, heat, osmotic, tactile or chemicals, and cannot be explained by any other form of dental defect or pathology. Laser therapy has become a commonly used intervention and might be effective for dentinal hypersensitivity.

OBJECTIVES

To assess the effects of in-office employed lasers versus placebo laser, placebo agents or no treatment for relieving pain of dentinal hypersensitivity.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 20 October 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2020, Issue 9), MEDLINE Ovid (1946 to 20 October 2020), Embase Ovid (1980 to 20 October 2020), CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 20 October 2020), and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; from 1982 to 20 October 2020). Conference proceedings were searched via the ISI Web of Science and ZETOC, and OpenGrey was searched for grey literature. The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomized controlled trials (RCTs) in which in-office lasers were compared to placebo or no treatment on patients aged above 12 years with tooth hypersensitivity.

DATA COLLECTION AND ANALYSIS

Two review authors independently and in duplicate screened the search results, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. For continuous outcomes, we used mean differences (MD) and 95% confidence intervals (CI). We conducted meta-analyses only with studies of similar comparisons reporting the same outcome measures. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

We included a total of 23 studies with 936 participants and 2296 teeth. We assessed five studies at overall low risk of bias, 13 at unclear, and five at high risk of bias. 17 studies contributed data to the meta-analyses. We divided the studies into six subgroups based on the type of laser and the primary outcome measure. We assessed the change in intensity of pain using quantitative pain scale (visual analogue scale (VAS) of 0 to 10 (no pain to worst possible pain)) when tested through air blast and tactile stimuli in three categories of short (0 to 24 hours), medium (more than 24 hours to 2 months), and long term (more than 2 months). Results demonstrated that compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through air blast stimuli at short term (MD -2.24, 95% CI -3.55 to -0.93; P = 0.0008; 13 studies, 978 teeth; low-certainty evidence), medium term (MD -2.46, 95% CI -3.57 to -1.35; P < 0.0001; 11 studies, 1007 teeth; very low-certainty evidence), and long term (MD -2.60, 95% CI -4.47 to -0.73; P = 0.006; 5 studies, 564 teeth; very low-certainty evidence). Similarly, compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through tactile stimuli at short term (MD -0.67, 95% CI -1.31 to -0.03; P = 0.04; 8 studies, 506 teeth; low-certainty evidence) and medium term (MD -1.73, 95% CI -3.17 to -0.30; P = 0.02; 9 studies, 591 teeth; very low-certainty evidence). However, there was insufficient evidence of a difference in pain intensity for all types of lasers when tested through tactile stimuli in the long term (MD -3.52, 95% CI -10.37 to 3.33; P = 0.31; 2 studies, 184 teeth; very low-certainty evidence). Most included studies assessed adverse events and reported that no obvious adverse events were observed during the trials. No studies investigated the impact of laser treatment on participants' quality of life.

AUTHORS' CONCLUSIONS

Limited and uncertain evidence from meta-analyses suggests that the application of laser overall may improve pain intensity when tested through air blast or tactile stimuli at short, medium, or long term when compared to placebo/no treatment. Overall, laser therapy appears to be safe. Future studies including well-designed double-blinded RCTs are necessary to further investigate the clinical efficacy of lasers as well as their cost-effectiveness.

Evaluation of the effect of dentin surface treatment by air abrasion and Er:YAG laser on the retention of metal crowns luted with glass ionomer cement in teeth with reduced crown height: An in vitro study

Aim and Objectives

The purpose of this study was to investigate the effect of dentin surface treatment with aluminum oxide air abrasion and Er:YAG laser on tensile bond strength of metal crowns. Metal crowns were luted with conventional glass ionomer cement (GIC) in the teeth with reduced crown height, where preparation geometry did not provide optimal retention form.

Materials and Methods

Forty-eight human premolars were prepared to receive metal crowns and were randomly divided into four groups for tensile bond strength testing. Group A: Untreated dentin luted with self-adhesive composite resin cement as positive control; Group B: Untreated dentin luted with GIC as negative control; Group C: Surface treatment with 50 μm aluminum oxide air abrasion and luted with GIC; Group D: Surface treatment with Er:YAG laser (λ =2.94 mm) with a total energy 84.88 J/cm² of (60 mJ/pulse, 10 Hz, 60 pulses, and 100 μs pulse width) and luted with GIC. The cemented specimens were thermocycled and later subjected to axial load in a universal testing machine at 0.5 mm/min cross-head speed for tensile testing. Scanning electron microscopic evaluation of dentin surface treatment and cement-dentin interface was also done in representative specimens.

Results

One-way analysis of variance showed statistically significant difference among/within the groups (P < 0.001). Tukey's post hoc test presented significant increased tensile bond strength of Er:YAG laser group. Air abrasion group showed no significant increase in tensile bond strength values (P = 0.033).

Conclusion

Dentin surface treatment with Er:YAG laser significantly improved the tensile bond strength of luting GIC compared to air-abraded and untreated dentin.

Comparison of an Er: YAG laser osteotome versus a conventional drill for the use in osteo- odonto-keratoprosthesis (OOKP)

OBJECTIVES

The osteo-odonto-kerato-prosthesis (OOKP) procedure is a complex, multi-stage, multidisciplinary surgical intervention for the treatment of severe corneal blindness. One step of the OOKP consists of creating a precise hole into a tooth in which an optic cylinder is subsequently inserted; its shape must ensure a perfect watertight fit. The Er: YAG laser (L) used in this study is part of CARLO®, the first laser osteotome that enables surgical planning based on computed tomography data, robot guidance, and a precise execution of laser cuts in teeth and bone tissue, using laser photoablation rather than conventional mechanical methods. The purpose of this study was to assess whether the Er: YAG laser is non-inferior compared to a conventional drill.

METHODS

Thirty-two bovine incisors were grounded to a thickness of 1.5 mm. In 16 teeth, a 3.5 mm hole was drilled progressively into each tooth, using dental burs (B) of increasing diameter that were attached to a fixed drill machine. In the other 16 teeth, a hole was created using an Er: YAG laser at a wavelength of 2.94 µm (Part of CARLO®). In seven teeth of each group, the cylinder was inserted and fixated with polymethylmethacrylate (PMMA) bone cement. In the remaining seven teeth of each group, the cylinder was inserted without fixation material (press-fit). After bonding and drying, all specimens were stored in water until force measurements were recorded using a uniaxial traction machine. The force required to move the optical cylinder out of the hole in the tooth was measured using an Instron 3344 testing system. Scanning electron microscope (SEM) and light microscope (LM) visualization of the holes created with the laser and the drill were performed in two teeth (SEM)/four teeth (LM) per method.

RESULTS

Significant differences (P < 0.001) were found for the following parameters: B PMMA versus B press-fit; B PMMA versus L press-fit; L PMMA versus B press-fit; L PMMA-L press-fit. This shows that PMMA bone cement fixation is superior to press-fit. No significant differences were found between B PMMA-L PMMA (P = 0.93) and B press-fit-L press-fit (P = 0.83). The SEM pictures showed a smoother surface using L.

CONCLUSIONS

The laser cut holes were as strong as bur-drilled holes, although SEM pictures showed a smoother surface of the laser cut holes. Hence, laser osteotomes open the possibility to custom fit the hole exactly to the width of the cylinder, which represents a potential advantage of the laser over the conventional bur. Lasers Surg. Med. 51:531-537, 2019. © 2019 Wiley Periodicals, Inc.

Comparative evaluation of neodymium-doped yttrium aluminum garnet laser with nanocrystalline hydroxyapatite dentifrices and herbal dentifrices in the treatment of dentinal hypersensitivity

Background

The aim of this study was to compare and evaluate the efficacy of neodymium-doped yttrium aluminum garnet laser with and without herbal and nanohydroxyapatite dentifrices in management of dentinal hypersensitivity (DH).

Materials and Methods

A total of 180 patients who responded to air-blast test and cold-water test using verbal rating scale (VRS) were included in this study. The patients were randomly assigned to six groups (n = 30): control group (CG), scaling and root planning (SRP) + nanocrystalline hydroxyapatite dentifrices, SRP + nanocrystalline hydroxyapatite dentifrices + laser, SRP + herbal dentifrices, SRP + herbal dentifrices + laser, and SRP + laser. Each group was evaluated at baseline, 1 week, 1 month, and 6 months. In every visit of each patient, their clinical examination was done.

Results

Among all groups', repeated ANOVA measures and Kruskal-Wallis test was performed in which laser groups showed maximum reduction in DH in all indices while the CG showed minimum reduction in DH. The VRS values showed maximum reduction in SRP + nanocrystalline hydroxyapatite dentifrices + laser group with mean of 0.3 ± 0.5 and minimum reduction in CG with mean of 3.0 ± 0.5 (P < 0.001).

Conclusion

Among all the groups, SRP + Nanocrystalline hydroxyapatite + Laser can be an effective treatment modality for DH.

Evaluation of Tooth Surface Irradiated With Erbium: Yttrium Aluminum Garnet and Carbon Dioxide Lasers by Atomic Force Microscopy

Introduction: Laser irradiation of dentin surface can affect its surface topography and roughness. Atomic force microscopy (AFM) is among the most efficient tools for determination of surface topography of natural biomolecules in nano-scales. Surface roughness affects plaque retention especially in the cervical region. This study aimed to assess and compare the obstruction of dentinal tubules and dentin surface roughness after irradiation of erbium: yttrium aluminum garnet (Er:YAG ) and CO2 lasers for treatment of dentin hypersensitivity (DH). Methods: Five disc-shaped samples measuring 3 mm in thickness were fabricated by horizontal sectioning of the cervical area of five extracted human molars using a low speed saw. Each disc was divided into 3 segments by a bur under water coolant. The three segments of each disc were placed on a glass slide. First segment: No intervention (control group). Second segment: Er:YAG laser irradiation (2940 nm, 50 mJ, 10 Hz and 0.5 W, 30 seconds) along with water coolant. Third segment: CO2 laser irradiation (10600 nm, 80 Hz, 0.3 W, 30 seconds) along with water coolant. After that, the surfaces underwent non-contact AFM. The diameters of dentinal tubules as well as surface roughness were then measured and statistically analyzed using repeated measures ANOVA. Results: The surface roughness parameters (Ra, Rq) showed increased roughness after laser irradiation and this increase in roughness after Er:YAG laser application was significant compared to the control group (P=0.048). However, CO2 laser caused no significant change in surface roughness. Also, after Er:YAG laser application, fewer open dentinal tubules were observed and the remaining open tubules had a smaller diameter. Conclusion: Based on the results, Er:YAG laser irradiation obstructs the dentinal tubules and increases the dentin surface roughness. This increase in surface roughness can cause microbial plaque retention and increase the risk of caries and periodontal disease. Application of CO2 laser (compared to Er:YAG) lead to slight but clinically significant obstruction of dentinal tubules and surface roughness.

Effects of different treatments on chemical and morphological features of eroded dentin

To evaluate the treatment of eroded dentin (Sensodyne Repair & Protect™, Er:YAG laser and combinations). The occlusal surfaces of 25 third molars were sectioned 1.5 mm in thickness. After an erosion cycle (5 min in demineralizing solution + 3 h in remineralizing solution; six cycles a day for 8 days), the samples were divided into five groups (n = 5): (E) erosion - control; (ES) erosion + Sensodyne Repair & Protect (NovaMin); (EL) erosion + Er:YAG laser (40 mJ, 10 Hz, 0.4 W, 50 μs, 3.1 J/cm², 63 W/cm²); (ELS) erosion + Er:YAG laser + Sensodyne; and (ESL) erosion + Sensodyne + Er:YAG laser. Following storage in ultrapure water (37 °C/14 days), the Ca/P ratio was evaluated by EDXRF and the morphology surfaces examined in SEM. The percentage of exposed dentin tubules was calculated. One-way analysis of variance and Tukey's test at 5% were used to treat the data. The Ca/P ratio was higher in E and ES groups. More exposed dentin tubules were found in E group and less exposed tubules were found in the ES group (p < 0.0001). When the toothpaste and laser were combined, the number of occluded dentin tubules was higher when laser was performed first (ELS). A positive effect was found when the laser and toothpaste were combined.

Efficacy of Diode Laser and Gluma on Post-Preparation Sensitivity: A Randomized Split-Mouth Clinical Study

OBJECTIVE

This study aimed to compare the efficacy of a 940-nm diode laser and Gluma desensitizer on post-preparation sensitivity of prepared teeth.

MATERIALS AND METHODS

Twenty patients with 76 teeth participated in the study. For each patient, prepared molar or premolar in one quadrant were individually irradiated by laser. In the symmetrical quadrant, Gluma was applied onto the prepared teeth. No treatment was performed in the control group. Temporary crowns were placed after preparation. Pain response to tactile stimulus was assessed at one day, one week, and two weeks using visual analog scale (VAS). Intergroup comparisons were made with Kruskal Wallis test (p < 0.05).

RESULTS

Mean VAS scores of the control group were statistically higher than laser and Gluma groups (p < 0.017). The difference between VAS scores of the laser and Gluma groups was statistically insignificant (p > 0.05).

CONCLUSIONS

A significant reduction in level of sensitivity after both treatments was observed. The reduction of sensitivity with Gluma was not significantly superior to laser. No significant additional reduction occurred in level of sensitivity from the first day to the second week after both treatments.

CLINICAL SIGNIFICANCE

The application of Gluma or a 940-nm diode laser may be considered as effective in reducing sensitivity after tooth preparation without superiority of either method. (J Esthet Restor Dent 28:405-411, 2016).

Microleakage in Class V Composite Restorations after Desensitizing Surface Treatment with Er:YAG and CO2 Lasers

Aims: Glutaraldehyde, CO₂ and Er:YAG lasers can be used for treatment of dentin hypersensitivity. However, their application may have adverse effects on the clinical service of restorations. This study aimed to assess the microleakage in composite restorations following surface treatment with Glutaraldehyde desensitizer, CO₂ and Er:YAG laser irradiation for treatment of dentin hypersensitivity. Materials and methods: This experimental study was conducted on 60 extracted sound human teeth. Class V cavities were prepared measuring 3×3 mm using a diamond bur. Specimens were randomly divided into 4 groups of 15. Group one:no surface treatment, Group two:applying Glutaraldehyde desensitizer, Groups of three and four were irradiated with CO₂ and Er:YAG lasers, respectively. Surfaces were restored with bonding agent (Single Bond 2, 3M, USA) and Z250 composite (3M, USA). Specimens were thermocycled and immersed in 1% methylene blue solution for 24 hours. Microleakage scores were assessed under a stereomicroscope at ×20 magnification. Data were analyzed using SPSS and the Kruskal Wallis test (P=0.05). Results: There was no significant difference between microleakage of groups in enamel margins (P=0.694). The difference in microleakage at the dentin margin was significant between groups (P=0.018). Conclusions: Application of Glutaraldehyde-desensitizer and CO₂ laser irradiation of surfaces prior to composite restoration do not increase microleakage at the enamel or dentin margins but tooth surface treatment with Er:YAG laser significantly increased the microleakage at the dentin margins.