The Effects of a Novel Nanohydroxyapatite Gel and Er: YAG Laser Treatment on Dentin Hypersensitivity

Abstract

Purpose: This study evaluates the effects of a novel nanohydroxyapatite gel and Er: YAG laser on the surface roughness, surface morphology, and elemental content after dentin hypersensitivity treatments. Methods: Dentin discs (2 × 3 × 3 mm3) were prepared from 75 human molars. Out of 75 human molars, 50 were used to evaluate surface roughness and randomly divided into five groups: Group ID (intact dentin), Group DD (demineralized dentin), Group BF (fluoride varnish/Bifluorid 10), Group Lsr (Er: YAG laser-50 mJ, 0.50 W, 10 Hz), and Group NHA (nanohydroxyapatite-containing gel). Dentin hypersensitivity was stimulated by 35% phosphoric acid for 1 min (except Group ID). The surface roughness (Ra, μm) was measured via contact profilometry (n = 10). Out of the 75 sound human molars, 25 were used to evaluate the surface morphology and elemental content using scanning electron microscopy and energy-dispersive X-ray spectroscopy (n = 5). The data were statistically analyzed using Welsch ANOVA, Games–Howell, Kruskal–Wallis, and Dunn tests (p < 0.05). Results: Group Lsr showed significantly lower surface roughness than Group NHA and Group BF (p < 0.05). The SEM analysis indicated that most of the dentinal tubules were obliterated for Group NHA. Precipitant plugs with partially occluded dentinal tubules were observed for Group BF, while partially or completely occluded tubules with a melting appearance were detected for Group Lsr. The EDS analysis revealed that Group NHA and Group Lsr presented similar calcium and phosphorus amounts to Group ID. All dentin hypersensitivity treatment methods could provide promising results in terms of tubular occlusion efficiency. However, laser treatment resulted in smoother surfaces, which could help prevent dental plaque accumulation.

Dentinal Hypersensitivity Treatment with 1064 nm and 980 nm Diode Laser

“…A large number of treatments were suggested for the management of DH. One of the most accepted and documented protocols aim to shield or seal the dentinal tubules to reduce nerve stimulation [7][8][9][10][11]. For this purpose, several desensitizing substances, such as potassium ions, arginine, and calcium carbonate, have been developed [7][8][9][10][11].…”

“…One of the most accepted and documented protocols aim to shield or seal the dentinal tubules to reduce nerve stimulation [7][8][9][10][11]. For this purpose, several desensitizing substances, such as potassium ions, arginine, and calcium carbonate, have been developed [7][8][9][10][11]. Comparative studies indicate varying levels of effectiveness for these agents, depending on the type of stimuli [11].…”

“…For this purpose, several desensitizing substances, such as potassium ions, arginine, and calcium carbonate, have been developed [7][8][9][10][11]. Comparative studies indicate varying levels of effectiveness for these agents, depending on the type of stimuli [11]. However, achieving long-lasting relief remains challenging.…”

“…Nanohydroxyapatite has garnered considerable attention for this purpose due to its biocompatible nature and inorganic bone structure, featuring crystals ranging in size from 50 to 1000 nm. This unique property of nanohydroxyapatite enables it to effectively fill small gaps and depressions on the enamel surface, potentially surpassing the efficacy of fluorides in DH management [11]. In an in-vitro study, Sahin et al [11] demonstrated that both Er: YAG laser and nanohydroxyapatite applications lead to significant DH obliteration; however, laser treatment with Erbium results in smoother surfaces, possibly aiding in the prevention of dental plaque accumulation [11].…”

“…This unique property of nanohydroxyapatite enables it to effectively fill small gaps and depressions on the enamel surface, potentially surpassing the efficacy of fluorides in DH management [11]. In an in-vitro study, Sahin et al [11] demonstrated that both Er: YAG laser and nanohydroxyapatite applications lead to significant DH obliteration; however, laser treatment with Erbium results in smoother surfaces, possibly aiding in the prevention of dental plaque accumulation [11]. Additionally, various in-home methods have been explored in the literature for DH management, offering supplementary or standalone treatment options based on the severity of the condition [8].…”