Comparative Evaluation Of Diode Laser And Two Different Desensitizing Agents, And Their Combined Effect On Dentinal Hypersensitivity In Cuspids And Bicuspids: An In-Vivo Study

Background: Dentinal hypersensitivity is characterized by short, sharp pain arising from exposed dentin in response to external stimuli. Although numerous desensitizing agents and laser-based therapies have been investigated, no single treatment has demonstrated consistently predictable and sustained efficacy. Combination approaches that simultaneously reduce dentinal permeability and modulate pain transmission may provide enhanced clinical benefit. Aim: To evaluate and compare the efficacy of nanohydroxyapatite, 38% silver diamine fluoride, diode laser, and their combined application in the management of dentinal hypersensitivity affecting cuspids and bicuspids. Materials and Methods: Seventy-five patients aged 20–50 years with clinically diagnosed dentinal hypersensitivity involving cuspids or bicuspids and associated with cervical abrasion or abfraction were randomly allocated into five groups of 15 patients each. Group A received nanohydroxyapatite, Group B received 38% silver diamine fluoride, Group C received diode laser therapy, Group D received nanohydroxyapatite followed by diode laser, and Group E received silver diamine fluoride followed by diode laser. Hypersensitivity was elicited using a standardized air-blast stimulus and assessed using the Short-Form McGill Pain Questionnaire. Assessments were performed at baseline, immediately after treatment, and on Days 1, 7, and 14. Intragroup and intergroup comparisons were performed using nonparametric statistical analyses. Results: All five treatment modalities produced statistically significant reductions in dentinal hypersensitivity over the study period (p < 0.001). Baseline scores were comparable among the groups (p = 0.679). At Day 14, mean hypersensitivity scores were 1.73 ± 0.80 for nanohydroxyapatite, 1.53 ± 0.92 for silver diamine fluoride, 1.07 ± 0.70 for diode laser, 0.40 ± 0.51 for nanohydroxyapatite plus diode laser, and 0.33 ± 0.49 for silver diamine fluoride plus diode laser. The overall intergroup difference was highly significant (p < 0.001). Both combination groups demonstrated significantly lower Day14 scores than either desensitizing agent alone, whereas neither combination differed significantly from diode laser alone. Conclusion: All evaluated modalities significantly reduced dentinal hypersensitivity. The combination of diode laser with either nanohydroxyapatite or 38% silver diamine fluoride produced the greatest reduction over 14 days, suggesting that laser-assisted desensitization may provide an enhanced clinical effect compared with desensitizing agents used alone. Longer-term randomized clinical trials are required to establish whether this advantage persists beyond the short-term follow-up period.