ABSTRACT
Though the Er:YAG laser (ErL) has been used in periodontal therapy, the irradiated tip damage has not been studied in detail. In this study, the change in the energy output, surface morphology, and temperature of quartz tips was evaluated following contact irradiation. Soft tissue, calculus on extracted human teeth, and porcine bone were irradiated by ErL for 60 min at 14.2 or 28.3 J/cm(2)/pulse and 20 Hz with or without water spray. The energy output ratio declined the most in the calculus group, followed by the bone and soft tissue groups with and/or without water spray. Carbon contamination was detected in all groups, and contamination by P, Ca, and/or other inorganic elements was observed in the calculus and bone groups. The rate of energy output reduction and the degree of surface alteration/contamination is variously influenced by the targeting tissue, temperature elevation of the tip and water spray.
Subject(s)
Alveolar Process/radiation effects , Dental Calculus/radiotherapy , Dental Instruments , Energy Transfer/radiation effects , Gingiva/radiation effects , Laser Therapy/instrumentation , Lasers, Solid-State , Quartz/chemistry , Quartz/radiation effects , Animals , Equipment Contamination , Humans , In Vitro Techniques , Microscopy, Electron, Scanning , Spectrometry, X-Ray Emission , Surface Properties/radiation effects , Swine , Temperature , WaterABSTRACT
Apatite cement containing porogen can be a useful material for the fabrication of biporous (macro- and microporous) apatite, which has gained much attention as a bone substitute material because of its large surface area and that it improves cell penetration. In the present study, the effects of added mannitol on the setting reaction and mechanical strength of apatite cement were evaluated. Apatite cements containing 0-40 wt% of mannitol were prepared and allowed to set in 0.9% saline kept at 37 degrees C for 1-7 days. Although the diametral tensile strength (DTS) value increased with time, it decreased with the amount of added mannitol. SEM observation and XRD analysis revealed that mannitol had no inhibitory effect on the transformation reaction of apatite cement to apatite. It was thus concluded that mannitol was a good candidate for the fabrication of biporous apatite because it is biocompatible, exhibits satisfactory dissolution behavior, and that it caused no inhibitory effects on the compositional transformation to apatitic material.
Subject(s)
Bone Cements/chemistry , Chondroitin Sulfates/chemistry , Hydroxyapatites/chemistry , Mannitol/chemistry , Succinates/chemistry , Biocompatible Materials/chemistry , Bone Substitutes/chemistry , Chondroitin Sulfates/ultrastructure , Crystallization , Drug Combinations , Materials Testing , Stress, Mechanical , Sugar Alcohols/chemistry , Tissue Scaffolds/chemistryABSTRACT
BACKGROUND: Despite the recent increase in application of Er:YAG laser for various dental treatments, limited information is available regarding the contact tips. This study examined the changes in energy output and surface condition of quartz and sapphire contact tips after Er:YAG laser contact irradiation for tooth enamel ablation. MATERIALS AND METHODS: Ten sets of unused quartz or sapphire contact tips were employed for contact irradiation to sound enamel of extracted teeth. The teeth were irradiated with Er:YAG laser at approximately 75 J/cm(2)/pulse and 20 Hz under water spray for 60 minutes. The energy output was measured before and every 5 minutes after irradiation, and the changes in morphology and chemical composition of the contact surface were analyzed. RESULTS: The energy output significantly decreased with time in both tips. The energy output from the sapphire tips was generally higher on average than that of the quartz. The contact surfaces of all the used quartz tips were concave and irregular. Most of the sapphire tips also appeared rough with crater formation and fractures, except for a few tips in which a high energy output and the original smooth surface were maintained. Spots of melted tooth substances were seen attached to the surface of both tips. CONCLUSION: In contact enamel ablation, the sapphire tip appeared to be more resistant than the quartz tip. The quartz tips showed similar patterns of energy reduction and surface alteration, whereas the sapphire tips revealed a wider and more characteristic variation among tips. Lasers Surg. Med. 41:595-604, 2009. (c) 2009 Wiley-Liss, Inc.
Subject(s)
Aluminum Oxide/radiation effects , Energy Transfer/radiation effects , Laser Therapy/instrumentation , Lasers, Solid-State , Quartz/radiation effects , Tooth Preparation/instrumentation , Dental Enamel/radiation effects , Humans , Surface Properties/radiation effects , Tissue Culture TechniquesABSTRACT
Periodontal disease is a chronic inflammatory disorder caused by bacterial infection. Laser treatment demonstrates specific characteristics that may be valuable in managing periodontal disease. In addition, lasers reduce stress and uncomfortable conditions for patients during and after treatment compared to other conventional tools. This article reviews the literature to describe the current clinical applications of lasers for gingival tissue management-including esthetic treatment, non-surgical and surgical periodontal pocket therapy, osseous surgery, and implant therapy.
Subject(s)
Laser Therapy , Periodontal Diseases/surgery , Dental Implants , Gingival Diseases/surgery , Humans , Lasers/classification , Periodontal Pocket/surgery , SafetyABSTRACT
OBJECTIVES: The purpose of this study was to investigate the DIAGNOdent values applicable as a guide for removal of outer layer of carious dentin with Er:YAG laser. METHODS: Carious dentin of human extracted molars was removed by bur with Caries Detector (Group 1: red stained dentin was left, Group 2: light pink stained dentin was left) and by Er:YAG laser with DIAGNOdent value as a guide (30>Group 3>21, 20>Group 4>11, 10>Group 5). The cavity floor dentin after removing carious dentin was examined using microradiograms, EPMA and SEM. RESULTS: The cavity floor dentin of group 1,3 showed the decreases in the degree of X-ray absorption. In group 2,4 and 5, decrease of Ca, P were not observed. The decrease of Mg was observed on the more superficial part of the cavity floor for group 3 than for group 4. CONCLUSIONS: When carious dentin was removed using Er:YAG laser, the carious dentin outer layer was ideally removed with DIAGNOdent values: 11-20. DIAGNOdent values: 11-20, could indicate the completion of outer layer removal of carious dentin with Er:YAG laser, but there are some problems that must be addressed before the clinical application.
Subject(s)
Dental Caries/radiotherapy , Dental Instruments , Dentin/ultrastructure , Laser Therapy , Aluminum/therapeutic use , Dental Caries/diagnostic imaging , Dentin/diagnostic imaging , Dentin/radiation effects , Erbium/therapeutic use , Humans , Radiography , Yttrium/therapeutic useABSTRACT
The purpose of this study was to examine the output energy changes of the contact probe for Er:YAG laser with tooth ablation and evaluate the effect of contact surface polishing on output energy. The Er:YAG laser was irradiated to enamel of extracted human incisors for 100 min (5 min x 20 times). The output energy of contact probes was measured every 5 min (n = 3). After 100 min, the contact surfaces were polished using silicon carbide paper up to #1500, and the output energy of the probe was measured. The contact surfaces of the probes were observed and analyzed using an EPMA. After 100 min, the output energy showed 49.4% of the energy of an unused probe. After the contact surfaces were polished to #1500, the output energy returned to 96.4% of baseline. It is suggested that the output energy of the contact probe decreased with tooth ablation, and polishing of the contact surface was effective to regain the energy.
Subject(s)
Lasers , Quartz/chemistry , Aluminum Silicates , Calcium/analysis , Carbon Compounds, Inorganic/chemistry , Dental Enamel/surgery , Electron Probe Microanalysis , Energy Transfer , Erbium , Humans , Phosphorus/analysis , Silicon/analysis , Silicon Compounds/chemistry , Surface Properties , Time Factors , YttriumABSTRACT
The purpose of this study was to investigate the contact probes of Er:YAG laser before and after tooth ablation. Three kinds of contact probe were prepared. The first was an unused probe (NE). The second was used to prepare 10 cervical cavities (KP). The third was a probe that was judged for an exchange by three dentists who had expertise with Er:YAG laser (EX). The surface observation and mapping analysis were performed. The contact surface of NE was a flat and smooth surface, only Si was observed. KP demonstrated an uneven surface, Si was observed throughout, with scattered indications of Ca and P. EX displayed regions of fracture along the edge and a surface exhibiting dissolved adherents in parts. It was suggested that micro-explosions have effects on not only the tooth substance, but also the contact surface of the probe.
Subject(s)
Dental Caries/therapy , Dental Cavity Preparation/instrumentation , Dental Restoration, Permanent/instrumentation , Laser Therapy , Electron Probe Microanalysis , Equipment Failure Analysis , Equipment Reuse , Equipment Safety , Humans , Laser Therapy/instrumentation , Surface PropertiesABSTRACT
BACKGROUND AND OBJECTIVES: The effects of Er:YAG laser irradiation on dentin have not been sufficiently investigated. The purpose of this study was to investigate the effects of Er:YAG laser irradiation on dentin. STUDY DESIGN/MATERIALS AND METHODS: After cavities were prepared using Er:YAG laser irradiation or rotary cutting instruments, histological observations of cavity-floor dentin utilizing polarizing microscopy, microradiography and light microscopy, and analysis of composition of cavity-floor dentin using Fourier-transformed (FT-IR) spectrometry were conducted. RESULTS: In the laser-treated side, a deeply stained basophilic layer was observed. The number of odontoblastic processes present was obviously less in the laser-treated side than in the bur-treated side. FT-IR analysis revealed that compared to the bur-treated side, a broad background peak at around 1,600 cm(-1) was present. CONCLUSIONS: Er:YAG laser irradiation might have denatured the organic materials of dentin.
Subject(s)
Dentin/radiation effects , Lasers/adverse effects , Microradiography , Microscopy, Polarization , Microscopy/methods , Spectroscopy, Fourier Transform Infrared , Basophils/pathology , Dental Cavity Preparation/methods , Dentin/ultrastructure , Eosine Yellowish-(YS) , Erbium , Humans , Odontoblasts/pathology , Rosaniline Dyes , Staining and Labeling/methods , Tooth/radiation effects , Tooth/ultrastructure , YttriumABSTRACT
BACKGROUND AND OBJECTIVE: We have reported that the application of ultrasonic scalers on the Er:YAG laser-irradiated enamel surface achieved bond strengths of approximately 16 MPa. However, it is reported that a bond strength of 20 MPa is needed to prevent the marginal gaps, so the tensile bond strength (TBS) of composite resin to the Er:YAG laser-irradiated enamel is still insufficient. STUDY DESIGN/MATERIALS AND METHODS: Various methods (phosphoric acid etching, air scaling, ultrasonic scaling, air powder polishing, combination with phosphoric acid etching, and prior mechanical removal methods) were tested as a technique to increase TBS of composite resins to the Er:YAG irradiated enamel. RESULTS: Both the methods of mechanical removal following Er:YAG laser irradiation and the phosphoric acid etching following irradiation and mechanical removal had significant effects on TBS. TBS in the group with acid etching following air powder polishing showed highest value, 22.0 MPa. CONCLUSION: The application of phosphoric acid etching following mechanical removal of Er:YAG laser irradiation was effective to achieve high bond strength.
Subject(s)
Composite Resins/radiation effects , Dental Bonding , Dental Enamel/radiation effects , Dental Scaling/instrumentation , Lasers , Acid Etching, Dental , Analysis of Variance , Humans , Incisor/ultrastructure , Microscopy, Electron, Scanning , Phosphoric Acids , Surface Properties , Tensile Strength , UltrasonicsABSTRACT
BACKGROUND AND OBJECTIVES: The investigation of adhesion between an Er:YAG laser-irradiated surface and composite resin is very important to ensure the best clinical results. The purpose of this investigation is to determine if the application of various treatments on Er:YAG laser-irradiated dentin surface affects the tensile bond strength between dentin and composite resins. STUDY DESIGN/MATERIALS AND METHODS: In this investigation, the application of phosphoric acid, ultrasonic scaler, air-scaler, and air-powder polisher were tested as techniques to increase the bond strength of composite resins to Er:YAG laser-irradiated dentin surface. RESULTS: The tensile bond strength of the air-powder polished group was highest, at 18.45 +/- 3.72 MPa, and the lowest value was that of the only laser-irradiated group, at 12.56 +/- 4.38 MPa. CONCLUSIONS: The bond strengths in treated with air-powder polished group and phosphoric acid etched group were significantly higher than that of the group in laser irradiation alone.
