Assessment of LASER- induced precipitation of MTA-nanoparticles on root canal dentin surface

Abstract

Aim of the study: This study aims to evaluate the effectiveness of a 980-nm diode laser in inducing mineral trioxide aggregate (MTA) nanoparticle precipitation on root canal dentin surfaces for dentinal coverage.

Materials and methods: Sixty mature single-rooted teeth were decoronated at a fixed length of 16 mm and instrumented to size #40/0.04. Canals were filled with either distilled water or nanoMTA suspension and randomly divided based on the treatment modality into: G I and G II flooded with distilled water and laser irradiated at 2 Watt and 4 Watt respectively, GIII and GIV flooded with nanoMTA suspension and laser irradiated at 2 Watt and 4 Watt respectively, G V, flooded with nanoMTA suspension without laser irradiation, and G VI flooded with distilled water without laser irradiation. All samples were longitudinally split and scanned by environmental scanning electron microscopy (ESEM) to evaluate dentinal tubule (DT) occlusion and MTA surface precipitation. Image J analysis software was used to quantify open DTs, while a scoring system assessed dentine coverage.

Results: Laser irradiation significantly enhanced nanoMTA precipitation and dentinal tubule occlusion. The highest dentinal surface coverage, indicated by the lowest pixel percentage, was in laser-irradiated nanoMTA suspension groups G IV (3.4 ± 3.1) and G III (16.7 ± 3), while the lowest coverage was in the non-irradiated saline group G VI (53.4 ± 9.6) (p < 0.05). Median dentinal coverage scores were also highest in G III and G IV (both = 4). G VI showed the least dentinal occlusion, with a statistically significant difference from other groups (p < 0.05).

Conclusion: The 980-nm diode laser effectively enhances MTA nanoparticle precipitation on root canal surfaces, improving dentinal tubule occlusion and sealing potential. Further research is warranted to optimize laser parameters, MTA suspension ratios and to assess clinical outcomes.

Fig. 1. ESEM micrograph of the dentin surface at the root canal at magnification 1000X.

Groups GI, II, III, IV, V, and VI are demonstrated from upper left till lower right respectively; the majority of the dentine surface is minimally covered A, the coalescence and diminish of dentinal tubules diameter B, majority of the dentine surface heavily covered C, D, sporadic precipitates on dentine surface E, and the normal dentine surface architecture in F.