Modification of dental enamel, dentin by an ultra-fast femtosecond laser irradiation: A systematic review

Objective: To assess literature for the effectiveness and impact of femtosecond (fs) laser irradiation for surface processing of enamel and dentine. Materials and methods: This systematic review followed PRISMA guidelines. Criteria for inclusion and exclusion were established, and searches undertaken in the PubMed/MEDLINE, Embase and, Scopus databases for articles published in English over a period of the last 25 years. In-vivo studies were excluded. Analysis explored the effects of varying laser parameters including the ablation threshold, ablation rate, relative ablation efficiency and the influence of laser processing parameters, such as the laser scanning speed, on purported surface changes and presumed thermal effects on dental enamel and dentin that arise directly as a result of fs laser irradiation. Results: Eleven articles that met the inclusion criteria reported that fs laser pulses can progressively remove (i.e., ablate) dental enamel and dentin with an acceptable precision and accuracy, with little or no observed thermal effects. These reported the use of an ultra-fast fs lasers employing different wavelengths, pulse durations and irradiation parameters, such as the output power and the pulse repetition rates. The chemical composition of enamel and dentin was found not to be significantly altered by an fs laser treatment. Conclusion: Significant efforts are still required to optimisefs laser parameters for precise and selective ablation of dental tissue and dentine to enable minimally invasive restorative procedures.

Automated summary

This systematic review assessed the effectiveness and impact of femtosecond (fs) laser irradiation for surface processing of enamel and dentine. The results showed that fs laser pulses can accurately and precisely ablate dental enamel and dentin with minimal thermal effects. However, further optimization of laser parameters is needed for precise and minimally invasive restorative procedures.