Effect of ND:YAG Laser Irradiation and Root Planing on the Root Surface: Structural and Thermal Effects

Abstract

Effects of ND:YAG laser irradiation on untreated and root planed tooth roots were investigated to determine whether a cleaning effect and/or removal of smear layer could be achieved without concomitant microstructural or thermal damage. Sixty (60) healthy extracted teeth were either untreated, irradiated only, root planed only, or irradiated and root planed. Intra-pulpal and surface temperatures were monitored during irradiation, then SEM was performed. Smear layer elimination was achieved without inducing hard tissue microstructural damage at 5W, using pulse durations and intervals of 0.1 s, a fluence of 0.77 J/cm2, and a total energy density of approximately 700 J/cm2. However, these results were not consistent in all samples. At these parameters, intra-pulpal temperature increases of 9 to 22 degrees C and surface temperature increases of 18 to 36 degrees C were recorded. Thus, despite their effectiveness for smear layer removal, these parameters may not be appropriate for clinical use as an adjunct to conventional periodontal therapy.

Root Surface Biomodification with Nd:YAG Laser for the Treatment of Gingival Recession with Subepithelial Connective Tissue Grafts

“…In previous clinical studies, it has been demonstrated that lasers are an effective tool in the field of root conditioning to improve the outcome of regenerative periodontal therapies by favoring the attachment of the regenerated periodontal structures. [32][33][34][35][36][37][38][39][40][41][42][43] The Nd:YAG laser has been reported to remove the smear layer, uncovering dentinal tubules and exposing collagen fibers on root surfaces. 37,38 The Nd:YAG laser, with noncontact delivery mode and short irradiation time, has caused no damage to or alteration of root surfaces.…”

“…[32][33][34][35][36][37][38][39][40][41][42][43] The Nd:YAG laser has been reported to remove the smear layer, uncovering dentinal tubules and exposing collagen fibers on root surfaces. 37,38 The Nd:YAG laser, with noncontact delivery mode and short irradiation time, has caused no damage to or alteration of root surfaces. 37 In addition, Tewfik et al 39 reported effects of Nd:YAG laser on root cementum topography and fibroblastic attachment, and suggested that the modification of cementum surfaces depends on the energy level of the laser irradiation.…”

“…The Nd:YAG laser application reported by some investigators exhibited, under SEM analysis, surface alterations such as charring, crater formation, and cement meltdown. 38,[46][47][48][49][50][51][52][53][54] Studies with Nd:YAG laser using different parameters 47,48 have shown that mean power settings ranging between 1.25-3.00 W promote a root surface change leading to fusion and resolidification of the cement mineral portion alongside crack and fissure formation. Thomas et al 46 reported that the Nd:YAG laser denatures root surface proteins, and they suggest that the complement of the conventional mechanical treatment of the root surface would be important on the reduction of these irregularities aiming for a more biocompatible root surface.…”

“…31 In addition to chemical conditioning, the applicability of different laser systems such as CO 2 , Nd:YAG, diode and Er:YAG laser in the removal of the smear layer have been demonstrated. [32][33][34][35][36][37][38][39][40][41][42][43] However, until now, no published data have been available concerning the clinical outcomes following root surface biomodification with Nd:YAG laser for the treatment of gingival recession. Therefore, the aim of the present study was to evaluate and compare the outcome of gingival recession therapy using the SCTG with or without Nd:YAG laser application for root surface biomodification.…”

Lasers and soft tissue: 'fixed' soft tissue surgery

“…This risk can exist through the penetration of short wavelengths or the conductive heat effects arising from long wavelength char that is super-heated. [5][6][7][8][9] It is advisable, therefore, to assess the thickness, vascularity and position of any target 6,[10][11][12] during the removal of a giant cell granuloma. Laser therapy has been cited as a possible modality in treating this condition.…”