Erbium laser ablation of dental hard tissue: Effect of water cooling

TLDR

Several lasers have been explored for hard dental tissue applications, but using them alone can cause potentially harmful temperature increases in the pulp chamber. The study aims to evaluate the effect of water cooling on Er:YAG laser ablation of hard dental tissues. An Er:YAG laser (λ = 2.94 µm) was used to ablate dentin and enamel, measuring ablation rates with and without a water‑cooling spray, and testing cooling effects at repetition rates up to 10 Hz with a 4.5 ml/min flow. Water spray minimally reduced dentin ablation rates and did not affect enamel rates, but effectively limited pulp chamber temperature rise to less than 3 °C at 10 Hz, 360 mJ/pulse, confirming safe use of the laser with cooling. © 1996 Wiley‑Liss, Inc.

Abstract

Background and Objective Several lasers have been explored for hard dental tissue applications; used alone they have resulted in potentially harmful temperature increases in the pulp chamber. Materials and Methods An Er:YAG laser (λ = 2.94 μm) was used to ablate hard dental tissues. Ablation rates with and without a water-cooling spray were measured. Subsequent experiments investigated the cooling effects of the water. Initially single channels were drilled into dentin; further studies involved ablating rectangular areas with repetition rates up to 10 Hz. Results The water spray minimally reduced the ablation rates of dentin and did not affect the ablation rates of enamel. The water spray effectively cooled the teeth; while using the maximum average power investigated (10 Hz, 360 mJ/pulse), a water flow rate of 4.5 ml/min limited the temperature rise in the pulp chamber to less than 3°C. Conclusion The studies confirm the feasibility of using an Er:YAG laser in conjunction with a water spray to safely and effectively remove hard dental tissues. © 1996 Wiley-Liss, Inc.