Abstract: PURPOSE: To evaluate the efficacy of Er:YAG laser combined with infiltration resin in the treatment of dental fluorosis of deciduous teeth. METHODS: Eighty-six children treated for deciduous fluorosis teeth at Hebei Medical University Dental Hospital from January 2019 to January 2024 were selected and randomly divided into the control group (n=43, 92 teeth) and experimental group(n=43, 116 teeth). The control group was treated with Opalustre micro-abrasion paste combined with infiltration resin, while the experimental group was treated with Er: YGA laser combined with infiltration resin. Clinical data of both groups were collected, changes in tooth shade, whitening effects and the rate of discoloration removal at baseline, 1 week and 3 months post-treatment were compared. Treatment satisfaction and the incidence of tooth sensitivity were also compared between the two groups. RESULTS: One week and three months post-treatment, the tooth shade scores in the experimental group were 3.42±0.51 and 3.86±0.62, respectively, significantly lower than those in the control group (5.82±0.75 and 7.23±1.02, P<0.05). The total effective whitening rate in the experimental group was 100.00% at both one week and three months post-treatment, significantly higher than that in the control group(94.57% and 84.78%, P<0.05). The rate of discoloration removal in the experimental group was 95.73%, significantly higher than that in the control group (88.13%, P<0.05). The VAS scores for post-operative pain at 2, 12 hours and 1 day in the experimental group were significantly lower than those in the control group(P<0.05). The treatment satisfaction rate in the experimental group was 96.55%, significantly higher than that in the control group (64.13%, P<0.05). The incidence rates of post-operative tooth sensitivity at 2 hours, 1 week and 3 months in the experimental group were 3.45%, 5.17% and 6.03%, respectively, significantly lower than those in the control group(15.22%, 22.83% and 28.26%, P<0.05). CONCLUSIONS: Er:YGA laser combined with infiltration resin demonstrats superior treatment efficacy for deciduous fluorosis teeth compared to the traditional combination of micro-abrasion paste and infiltration resin. It not only effectively improves dental aesthetics, but also reduces dental sensitivity after treatment, and improves patient satisfaction.

Key words: Er: YAG laser, Infiltration resin, Deciduous teeth, Fluorosis teeth, Treatment efficacy, Teeth whitening