The Effect of Laser Surface Treatment on the Bond Strength of Adhesive Materials to Primary Teeth: A Systematic...

This systematic review aimed to evaluate the effect of laser surface treatment on the bond strength of adhesive restorative materials to primary teeth. A comprehensive literature search was conducted in PubMed, Scopus, Embase, Web of Science and WorldCat up to July 2025 using the keywords primary teeth, deciduous teeth, milk teeth, laser, adhesion, bond strength. Twenty-six studies met the inclusion criteria, including 22 shear bond strength (SBS), three microtensile bond strength (µTBS) and one microshear bond strength (µSBS) investigations. Most studies evaluated erbium lasers (Er:YAG, Er,Cr:YSGG), while fewer assessed diode, Nd:YAG or KTP devices. In dentin, erbium lasers at low-to-moderate energy levels consistently produced smear-free, micro-retentive surfaces with open tubules and bond strengths comparable to bur-prepared controls. High-energy irradiation, however, frequently caused microcracks, tubule collapse and reduced adhesion. In enamel, phosphoric acid etching remained the most effective conditioning method, although combined laser-acid pretreatment often improved bonding of sealants and composites. Material-dependent effects were also evident: resin composites generally outperformed glass ionomers, hybrids and bioactive restorative materials. Phosphoric acid etching remains indispensable for enamel conditioning, while dentin benefits from carefully controlled erbium laser irradiation in combination with suitable adhesive systems.