SEM Evaluation of tooth surface irradiated by different parameters of Er:YAG laser

(1) Background: This study aimed to evaluate the microporosity of the tooth surface structure adjacent to the cemento-enamel junction (CEJ) after the removal of composite fillings with a drill in comparison with removal by an Er:YAG laser and after cleaning with a periodontal curette, chemical EDTA and NaOCl (sodium hypochlorite) conditioning. (2) Methods: The research material consisted of 30 extracted premolars with cervical composite fillings. The teeth were divided into six groups according to the method of tooth preparation: group G1 (n = 5)—a diamond drill; group G2 (n = 5)—a diamond drill + curette; group G3 (n = 5)—a diamond drill + 24% EDTA (PrefGel, Straumann, Switzerland); group G4 (n = 5)—an Er:YAG laser (LightWalker, Fotona, Ljubljana, Slovenia) set with the following parameters: power: 1.65 W (composite removal, CR), 1.2 (tooth conditioning, TC), energy: 110 mJ (CR), 80 mJ (TC), frequency: 15 Hz, pulse duration: 50 μs, tip diameter: 1 mm, air/fluid cooling: 4, distance 1.5 mm, energy density: 14.01 J/cm2 (CR), 10.19 J/cm2 (TC); group G5 (n = 5)—an Er:YAG laser + 2% sodium hypochlorite (NaOCl); group G6 (n = 5)—an Er:YAG laser + 5.25% NaOCl. In each tooth, three cavities were made and subjected to analysis. The dentin surface was evaluated using a scanning electron microscope (SEM). (3) Results: Groups G1 and G2 exhibited mechanical damage to the tooth surface structure caused by the rotary motion of a diamond drill. The SEM image showed a smear layer that could only be removed chemically using 24% EDTA gel (group G3). The tooth surfaces prepared with the Er:YAG laser (groups G4–G6) revealed a homogeneous structure without damage along with open dentinal tubules (without smear layer) and visible denaturation of collagen fibers. The sodium hypochlorite (NaOCl) conditioning did not increase the visibility of dentinal tubules. (4) Conclusions: Dentin surfaces have open dentinal tubules after removal of the composite filling using the Er:YAG laser and therefore do not require additional NaOCl conditioning.

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Effect of Er:YAG Laser Irradiation on Shear Bond Strength of Two Porcelain Laminate Veneers Bonded to Tooth Surface

Journal of Islamic Dental Association of IRAN ◽

10.30699/jidai.32.1.2.21 ◽

2020 ◽

Vol 32 (1) ◽

pp. 21-29

Author(s):

Ehsan Morshedi ◽

Maryam Azimi Zavaree ◽

Seyed Mohammad Reza Hakimaneh ◽

Sayed Shojaedin Shayegh ◽

Maryam Pirmoradian ◽

...

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Shear Bond Strength ◽

Er:Yag Laser ◽

Tooth Surface ◽

Laminate Veneers

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Laser Aided Ceramic Restoration Removal: A Comprehensive Review

Journal of lasers in medical sciences ◽

10.15171/jlms.2019.14 ◽

2019 ◽

Vol 10 (2) ◽

pp. 86-91 ◽

Cited By ~ 1

Author(s):

Rezvaneh Ghazanfari ◽

Nahal Azimi ◽

Hanieh Nokhbatolfoghahaei ◽

Marzieh Alikhasi

Keyword(s):

Bond Strength ◽

Temperature Rise ◽

Temperature Increase ◽

Shear Bond Strength ◽

Er:Yag Laser ◽

Tooth Surface ◽

Laser Application ◽

Conventional Procedure ◽

Tooth Surfaces ◽

Ceramic Restorations

Introduction: All-ceramic restorations are being widely used due to its various advantages. However, they have restricted durability and may have to be removed. The conventional procedure for removal is grinding the restoration with rotary instruments which are considered time-consuming and inconvenient. A newer advantageous method is the application of lasers for debonding ceramics from the tooth surface. The objective of this study is to provide a comprehensive literature review on laser-aided ceramic restorations debonding. Methods: We searched PubMed and Google Scholar databases. Seven articles from 2011 to 2018 were identified. Studies were assessed for the efficacy of laser application and the amount of pulpal temperature rise. Results: Studies selected were categorized according to variables including shear bond strength, debonding time and intrapulpal temperature. Oztoprak and Iseri investigated that erbium-doped yttrium, aluminum, and garnet (Er:YAG) laser application reduced shear bond strength of ceramic laminate veneers. The time of debonding took an average of 190 seconds in Rechmann’s study and 106 seconds in Morford’s study. One of the main issues while using the laser is thermal irritation of the pulp. A 5.5°C temperature increase may cause pulpal damage according to Zach and Cohen. Philips et al and Rechmann et al reported no intrapulpal harm due to temperature increase. Additionally, Phillips et al demonstrated that the laser setting affects both the debonding time and the temperature alterations and that a laser adjustment of 2.5 W/25 Hz would be the best safest group. Conclusion: Removal of ceramic crowns and veneers from tooth surfaces can be successfully done by Er:YAG laser application in a less time-consuming procedure and without any harm to the underlying dentin. However, a temperature rise in the pulp may occur which could be overcome by adequate air water cooling.

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Influence of Er:YAG Laser on Objective and Subjective Parameters of Stress during Sealant Application in Children

Folia Medica ◽

10.1515/folmed-2017-0086 ◽

2018 ◽

Vol 60 (2) ◽

pp. 275-282 ◽

Cited By ~ 1

Author(s):

Maria P. Shindova ◽

Ani B. Belcheva ◽

Nonka G. Mateva

Keyword(s):

Er:Yag Laser ◽

Dental Anxiety ◽

Equal Treatment ◽

Tooth Surface ◽

Dental Visit ◽

Subjective Stress ◽

Fissure Sealant ◽

Application Technique ◽

Occlusal Surfaces ◽

Stress Parameters

Abstract Background: Acceptance of lasers as alternatives and accessory tools to traditional methods in dental medicine has created an explosion of interest. Er:YAG laser is recommended for enamel conditioning. There is no study evaluating the anxiety in children during fissure sealing procedures when using Er:YAG laser compared to the routine application technique. Aim: To evaluate the objective and subjective stress parameters in children during a preventive procedure when using Er:YAG laser for additional enamel conditioning before pit and fissure sealant application compared to the routine clinical application technique. Materials and methods: The study included sixty-four 6-12-year-old children, divided into two equal treatment groups. A standardized fissure sealant application was performed, as in the intervention group before acid etching, the occlusal surfaces of teeth were conditioned with Er:YAG laser (2940 nm). During the procedure, objective and subjective stress parameters were recorded. Results: Significantly lower degree of dental anxiety was found at the end of the dental visit of the study group (p<0.001). During the professional cleaning of the tooth surface, the mean heart rate was low (95.55±14.29 bpm) within the physiological normal range. The objective and subjective stress parameters show no significant differences between the two subgroups during sealing procedure (p>0.05). Conclusions: Application of Er:YAG laser during sealant application does not provoke anxiety and is well accepted by children in dental environment. Preventive procedures at the beginning of a dental visit decrease the initial levels of dental anxiety and contribute to an effective treatment process.

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Optimization of Humid Conditions Using an Ultrasonic Nebulizer for the Fabrication of Hydroxyapatite Film with the Er:YAG Laser Deposition Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.720.269 ◽

2016 ◽

Vol 720 ◽

pp. 269-274 ◽

Cited By ~ 1

Author(s):

Ei Yamamoto ◽

Nobuhiro Kato ◽

Yuka Hatoko ◽

Shigeki Hontsu

Keyword(s):

Laser Ablation ◽

Er:Yag Laser ◽

Titanium Substrate ◽

Laser Deposition ◽

Tooth Surface ◽

Material Surface ◽

Coating Film ◽

Deposition Method ◽

Humid Condition ◽

Restoration Technique

Restoration and maintenance of tooth substance are primary concerns in operative dentistry. Intact tooth is mainly composed of hydroxyapatite (HAp). However, there are no practical HAp materials for the treatment of tooth decay and hypersensitivity. We have newly proposed and developed a tooth restoration technique with intraoral laser ablation using an Er:YAG laser in order to form the HAp thin film on tooth surface in the atmosphere at room temperature. However, the fabricated HAp film is not uniform for the present due to the unsettled water condition at the material surface during the laser ablation. In the present study, we tried to optimize the humid condition using a nebulizer for the fabrication of HAp layer with the Er:YAG laser deposition method. The HAp layers were fabricated on a titanium substrate while changing the flow rate of water mist in order to determine the relationship between the spraying amount and the HAp layer structure. It is revealed that there exists the optimal humid condition to fabricate the uniform hydroxyapatite coating film with the Er:YAG laser deposition method.

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Can the Method of Primer Application Influence Adhesion to Er:YAG-laser Irradiated Dentin?

The Journal of Contemporary Dental Practice ◽

10.5005/jcdp-10-1-49 ◽

2009 ◽

Vol 10 (1) ◽

pp. 49-57

Author(s):

Adriana B. Matos ◽

Sérgio B. Botta ◽

Samuel N. Vieira ◽

Rosely Cordon ◽

Márcia M. Marques

Keyword(s):

Bond Strength ◽

Composite Resin ◽

Er:Yag Laser ◽

Surface Preparation ◽

The Self ◽

Tooth Surface ◽

Preparation Technique ◽

Application Method ◽

Application Methods ◽

Etching System

Abstract Aim The aim of this study was to evaluate how cavity preparation and primer application methods influence the adhesion of composite resin to dentin using a self-etching system. Methods and Materials Forty-eight extracted, sound human molars were divided into six groups (n=8) according to the method used for the surface preparation of the teeth (#600-grit paper disc, diamond bur, and Er:YAG laser) and the primer application method utilized (active or passive). Following the adhesive procedure using a self-etching system, 5 mm high composite buildups were created with Z-250 composite resin. After storage in water at 37°C for 24 hours, the specimens were vertically sectioned into serial 1 mm2 sticks and tested for microtensile strength (μ-TBS). Nine additional molars were prepared for morphological analysis using scanning electron microscopy (SEM). Results Statistical analysis showed surface preparation technique (p<0.00) and primer application methods (p<0.001) do influence bond strength of the self-etching system tested. The best adhesion was achieved with specimens having the dentin ground with sandpaper followed by those ground with diamond burs. The worst bonding was obtained with Er:YAG laser ablated dentin. The active primer application method increased bonding performance compared to the passive method. Conclusions Within the limitations of the study, it can be stated surface treatment can influence the bond strength of the self-etching system tested and the active primer application method is more effective in achieving success in bonding to dentin compared with the passive application method. Clinical Significance Clinicians should use the active application method to apply a mild acidic self-etching primer along with an appropriate tooth surface preparation to facilitate the bond strength between dentin and composite resin. Citation Botta SB, Vieira SN, Cordon R, Marques MM, Matos AB. Can the Method of Primer Application Influence Adhesion to Er:YAG-laser Irradiated Dentin? J Contemp Dent Pract 2009 January; (10)1:049-057.

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