Journal of Dental Medicine

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Statement of Problem: One of the important indications for the extraction of mandibular impacted third molar is to preserve the periodontal health of the adjacent second molar from the destructive effects of plaque accumulation, acute and chronic inflammation.
Aim: The purpose of this study was to determine the effect of mandibular third molar surgery on the PDL of the adjacent molar.
Materials and Methods: Thirty patients, referred to the department of maxillofacial surgery, Tehran University of Medical Sciences, were selected, based on the desirable conditions. They had no history of systemic diseases and their adjacent molar was healthy. Probing depth (PD) at seven points and attachment level (AL) at three points were measured preoperatively. Standardized periapical radiographics were taken regularly for all patients. All the above-mentioned procedures repeated after three months of surgery. Findings were analyzed by Paired t-test.
Results: A significant difference in probing depth (PD) was observed before and after surgery, meaning that probing depth decreased after mandibular third molar surgery. Attachment level was also decreased post operatively moreover. Intrabony defects (IBD) showed healing after surgery.
Conclusion: Considering the limitations of the present study, impacted third molar surgery is suggested to prevent periodontal problems of the adjacent molar.

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Background and Aim: The treatment of epulis fissuratum is surgery, but a new proposed modality is laser surgery. The aim of this study was the comparison between laser and blade surgery in the treatment of epulis fissuratum.

Materials and Methods: In this clinical trial, 12 patients with epulis fissuratum were selected. The lesions were divided into two parts. One part was resected by laser and the other by surgical blade randomly and single blinded. The time of surgery, bleeding, wound repairment as well as the depth of vestibule were measured. Data were analyzed using Wilcoxon sign test and Paired t test with P<0.05 as the limit of significance.

Results: The wound of laser surgery healed sooner and the depth of vestibule in laser side was deeper comparing with blade surgery. Also the time of surgery was less than blade.

Conclusion: Based on the results of this study, we suggest that laser surgery is a more useful technique for the treatment of epulis fissuratum.

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Background and Aims: Nowadays lasers are used as alternatives to the tooth preparation because of reducing pain, bloodshed and stress. The aim of this study was to observe the effect of Er,Cr:YSGG laser on the dental hard tissues.

Materials and Methods: For this studty, molar teeth with no caries or dental restoration and enamel cracks were used. The laser power were taken from 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5 up to 6 Watts for enamel and 0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4 Watts for dentine simultaneously with water spray. The ablation effect was observed on both enamel and dentine. Finally, by use of a CCD camera connected to the computer, the dimensions of ablated areas were measured and results were applied in graphs.

Results: Volume of ablation was increased by increasing laser power. Also, by increasing energy value in each stage, the depth of ablation was increased for enamel and dentine. SEM images of ablations by 3.5 and 4 Watts on enamel and 1 and 1.5 Watts on dentine did not show any sharp edges.

Conclusion: The ablation volumes and depth increased by increasing the energy of laser pulses power. The reason for this trend was due to the water spray while irradiating and good absorption of water by laser beam.