Do erbium lasers promote changes in the tooth enamel during debonding of ceramic laminate veneers? A systematic review.

The longevity of ceramic laminate veneers can be influenced by several factors, which can result in the need for a removal process. Laser removal has emerged as a good alternative to facilitate the procedure, and its repercussions on tooth enamel have been investigated. We aimed to evaluate the efficacy of erbium lasers for debonding ceramic laminate veneers without damaging the tooth enamel. This systematic review based on the PICOS model adhered to the PRISMA statement. The PubMed/MEDLINE, Web of Science, Embase, and Scopus databases were systematically searched until December 1, 2022, and 2902 studies were retrieved. After screening, four in vitro studies that analyzed the dental morphology using scanning electron microscopy, optical analysis, stereomicroscopy, or x-ray dispersion spectroscopy were included. The risk of bias was assessed using the Cochrane Collaboration tool. Our findings suggest that erbium lasers are useful for ceramic laminate veneer removal without damaging the tooth enamel. However, the removal is influenced by the type and thickness of ceramic and type of cement used. It could be concluded that the application of Erbium laser did not promote superficial changes in the dental enamel. This effect was observed in all analysis performed.

Effect of osteoblasts on osteoclast differentiation and activity induced by titanium with nanotopography.

Titanium with nanotopography (Ti Nano) favors osteoblast differentiation and attenuates the osteoclast inhibitory effects on osteoblasts. Because the interactions between nanotopography and osteoclasts are underexplored, the aims of this study were to evaluate the effects of Ti Nano on osteoclast differentiation and activity, and the influence of osteoblasts on osteoclast-Ti Nano interaction. The discs were conditioned with a mixture of 10 N H2SO4 and 30% aqueous H2O2 to create Ti Nano and non-conditioned Ti discs were used as control (Ti Control). Osteoclasts were cultured on Ti Control and Ti Nano in the presence of osteoblasts in an indirect co-culture system. Also, osteoclasts were cultured on polystyrene and calcium phosphate plates in conditioned media by osteoblasts grown on Ti Control and Ti Nano. While Ti Control exhibited an irregular and smooth surface, Ti Nano presented nanopores distributed throughout the whole surface. Additionally, anisotropy was higher on Ti Nano than Ti Control. Nanotopography favored the gene expression of osteoclast markers but inhibited osteoclast differentiation and activity, and the presence of osteoblasts enhanced the effects of Ti Nano on osteoclasts. Such findings were mimicked by conditioned medium of osteoblasts cultured on Ti Nano, which reduced the osteoclast differentiation and activity. In conclusion, our results indicated that nanotopography regulates osteoblast-osteoclast crosstalk and further investigations should focus the impact of these bone cell interactions on Ti osseointegration.