We compared Erbium (Er):YAG laser with a surgical bur for removal of partially erupted lower third molars. Patients were randomised to be treated by either laser or bur. A total of 42 patients ...(laser=22; bur=20) were treated. A greater reduction in the range of mouth opening was found after laser than after bur treatment. Postoperative pain was more common after bur treatment. The duration of operation was considerably longer with laser than with bur. No persistent complications were encountered.
Introduction: The comparison of tissue quality and its restoration after contact, and non-contact Er: YAG (2940 nm) laser radiation ablation was evaluated. Methods: Laser setting for contact ablation ...was 250 mJ/pulse, pulse repetition rate 15 Hz, average power 3.75 W. For non-contact ablation these values were: 600 mJ/pulse, 6 Hz, 3.6 W. Structure of enamel and dentin after laser ablation was analyzed in scanning electron microscope. All cavities were filled by sonic-activated composite resin. Chemical and mechanical bond was observed in scanning electron microscope.Microleakage was assessed quantitatively by the degree of methylene blue dye penetration. Fischer exact test (p < 0.05) was used for statistical evaluation. Results: Contact and non-contact laser treatments prepared similar cavities (5167.31 μm versus 5356.31 μm). Defocusing of non-contact therapy has direct influence on the dye penetration microleakage presence (481.19 μm versus 611.94 μm) but this increase was not statistical significant. Conclusion: Cavity prepared by contact mode with sonic-activated composite filling protects microleakage formation.
Irritation fibroma is an overgrowth of submucosal tissue caused by prolonged local irritation from teeth or dental prostheses. It is extremely rare during the first decade of life and usually occurs ...in adult women.We encountered a one-year-11-month-old boy who had an overgrowth of palatal gingival tissue,subsequently diagnosed as irritation fibroma.A good prognosis was obtained after the removal of the fibroma with Er : YAG laser. We used Erwin AdvErL, (Morita MGF) as the laser apparatus, and the irradiation condition was 100 mJ, 10 pps or 20 pps performed with either a cone- or brush- shaped irradiation tip. The boy was cooperative throughout the surgical procedure and did not complain of any discomfort after the operation. The definitive diagnosis of irritation fibroma was provided after pathological examination, and gingival stimulation from thumb sucking was thought to be the cause of the progression of the lesion.These results suggest that the Er : YAG laser is useful for minor surgery in pediatric dentistry.
ABSTRACT
Background
Gingival melanin pigmentation often occurs as the result of abnormal deposition of melanin. Melanin pigmentation is completely benign and presents no medical problem. However, ...patients complain the esthetic problem as ‘Black Gum’. The aim of this study was to compare the effectiveness of depigmentation by Er:YAG laser and cryosurgery.
Materials and methods
This study included 20 patients with gingival pigmentation of maxillary incisors, aged 15 to 44 years. Excluding criteria were smoking, systemic disease and pregnancy. Patients treated randomized split mouth, with Er:YAG laser (Pd: 120 mj, RR:12 Hz) along with water spraying of half of maxillary gingivae and on the opposite side cryosurgery was done under topical anesthesia. Patients were followed up at 1, 2, 4 weeks and 3, 6, 12 months after treatment.
Results
Healing was uneventful follow-up period for 6 to 12 months showed no repigmentation in none of them. Slight erythema was observed. No postoperative swelling, hemorrhage, pain, infection were reported.
Conclusion
Depigmentation of gingival melanin hyperpigmentation by cryosurgery and Er: YAG laser radiations were found to be an effective procedures. Postoperative patient's satisfaction were impressive.
How to cite this article
Farahmand A, Moghareh Abed A, Mansouri Y. Clinical Application of Er: YAG Laser and Cryosurgery in Gingival Depigmentation. World J Dent 2014;5(2):102-108.
We often use the Er: YAG laser for dental treatment as it has been shown to be excellent for preparing the hard tissues of teeth. However, it has been reported that the bond strength and marginal ...seal of composite restorations is adversely affected in dentin irradiated by the Er: YAG laser compared with non-irradiated dentin. We used the marginal leakage test and the shear bond test to evaluate the marginal seal of restorations placed in laser-irradiated cavities. The teeth were restored using the composite resin filling method with glass ionomer cement and flowable composite resin as lining materials. We found that the shear bond strength of conventional composite resin, flowable composite resin and low-shrinkage composite resin was significantly decreased for laser-irradiated dentin compared with that for conventionally prepared dentin, and that the bond strength of resin-modified glass ionomer cement to laser-irradiated dentin. Although the marginal seal of the laser-irradiated dentin wall was not improved when the dentin was lined with conventional glass ionomer cement and flowable composite resin or when it was filled by conventional methods, it was improved when lined with resin-modified glass ionomer cement or filled with low-shrinkage composite resin. Our results suggest that lining with resin-modified glass ionomer cement or the use of low-shrinkage composite resin improves the marginal seal of composite resin restorations placed in Er: YAG laser-irradiated cavities.
Dentin conditioning can affect the adhesion of stem cells in endodontic regenerative treatments. This study aimed to assess the effects of the most commonly used endodontic irrigants, namely, ...ethylenediaminetetraacetic acid (EDTA), MTAD, and QMix in comparison with Er:YAG laser (as a novel modality for root canal disinfection) on the adhesion of stem cells from the apical papilla (SCAPs) to dentin.
Forty dentin specimens were prepared and subjected to different treatments in 5 groups (n=8) of control, irrigation with EDTA for 1 minute, irrigation with MTAD for 5 minutes, irrigation with QMix for 5 minutes, and Er:YAG laser irradiation. SCAPs were isolated from third molar tooth buds that two-thirds of their roots had formed. The cells were cultured on dentin specimens for 3 days and were counted using scanning electron microscopy (SEM).
MTAD resulted in significantly lower adhesion of cells to dentin compared with other groups (
<0.05). All other modalities induced cell adhesion with no significant difference with each other (
>0.05).
Despite many favorable properties, MTAD cannot serve as an optimal irrigant in endodontic regenerative procedures since it inhibits the adhesion of SCAPs to dentin and impairs an important step in tissue engineering.
Endodontic Regeneration, Er-YAG laser, MTAD, QMix, EDTA, SCAP, stem cell adhesion.
Objective To compare the efficiency of four methods that remove calcium hydroxide in root canals and to guide clinical practice. Methods Sixty-five isolated mandibular single root canal premolars ...were collected. After crown cutting and root canal preparation, a tooth was randomly selected as the blank control group, and the remaining 64 teeth were equally divided into Groups A and B (n = 32). Group A was injected with water-soluble calcium hydroxide, and Group B was injected with oil-soluble calcium hydroxide. After 2 weeks of drug sealing, Groups A and B were randomly divided into 4 groups (n = 8), including the lateral opening syringe group, sonic vibration group, ultrasonic group, and Er: YAG laser group. Before and after calcium hydroxide removal, the samples were scanned by cone-beam CT, and the data were imported into Mimics for 3D reconstruction. The root canal was divided into the following segments: superior root segment, middle and apical, and the calcium hydroxide volume of each segment of the root
The purpose of this study was to evaluate the combined effects of citric acid and glutaraldehyde (GA) on the resin bonding to Er : YAG laser‐irradiated dentin. Bovine dentin was prepared with 180‐ to ...600‐grit SiC paper and then uniformly irradiated with an Er : YAG laser (laser‐irradiated group) or immersed in water at 60°C for 15 min (heated group). The samples were then acid‐conditioned with 10% citric acid (10‐0) or 10% citric acid/3% ferric chloride (10‐3) for 15 s and treated with GA for 10 min before bonding to an acrylic rod with 4‐META/MMA‐TBB resin. These samples were trimmed to prepare miniaturized dumbbell‐shaped specimens. After storage in water at 37°C for 1 d, the tensile bond strength was measured, and the fractured surface was evaluated using a scanning electron microscope (SEM). In the laser‐irradiated and heated groups, the 10‐3+GA‐treated specimen had higher bond strength than that of 10‐0+GA. On the other hand, the tensile bond strength of 10‐3+GA in the non‐irradiated group was lower that that of 10‐0+GA. In conclusion, the combination of 10‐3 and GA for bonding with 4‐META/MMA‐TBB resin was the most effective for Er : YAG laser‐irradiated dentin and heated dentin, but it was not effective for the non‐irradiated dentin.
Objective: Recently, the Er: YAG laser has been applied clinically and shown excellent effectiveness for the ablation of dental hard tissue. However, its ablation efficiency is significantly inferior ...to that of high-speed rotary ablation, and the longer treatment time has posed problems. To improve the ablation efficiency, attempts to increase the tip output and pulse repetition rate have been made, but various problems, including the effect on dental pulp, remain unresolved. Paying particular attention to the irrigation device, our study group prepared a test tip that sprays the irrigation fluid as a mist by modifying the conventional irrigation mechanism with the cooperation of J. Morita Mfg, and evaluated the ablation efficiency. Materials and Methods: Healthy human molar teeth, used as samples, were filed to the enamel and dentin using a model trimmer, polished using waterproof abrasive paper to #2000, and irradiated with a laser by operating the moving stage at 1 mm/s. Laser irradiation was performed by setting the distance to the sample at 0.5, 1.0, and 2.0 mm. The group in which laser irradiation was performed using C600F was regarded as a control group, and the group in which laser irradiation was performed using the test tip was regarded as the mist spray group. Each sample was examined under a laser microscope, and the cross-sectional area was calculated (n=5). Results: The cross-sectional area was significantly greater in the mist spray group than in the control group at an irradiation distance of 0.5 mm in enamel and at 0.5 and 1.0 mm in dentin (p<0.05). Conclusion: In laser ablation of dental hard tissue, spraying the irrigation fluid as a mist is considered to be effective for improving the ablation efficiency.
The purpose of this study was to evaluate marginal leakage of composite resin restoration from cavities prepared by Er: YAG laser. The observation of the dentin surface after the application of laser ...irradiation was performed by LSM, the cutting surface showed a rough surface similar to scales, and exposed dentinal tubules were observed without striations or a smeared layer formation that were observed when using a rotary cutting device. Leakage tests revealed no significant differences in the marginal seal for both enamel and dentin between cavities prepared by Er: YAG laser irradiation and when using an air-turbine. In this study, the usefulness of cavity preparation by Er: YAG laser irradiation in composite resin restoration was suggested.
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