Er:YAG clinical results on hard tissue: phase II

The Use of Er:YAG Laser for Cavity Preparation: An SEM Evaluation

“…In clinical practice, patients reported more comfort and acceptance of laser treatment due to decreased noise discomfort, no contact and vibration, minimal pain sensation and reduced need for local anesthesia, and reduction of psychological trauma and fear during dental appointment (Cozean and Powell, 1998;Den Besten et al, 2001;Hibst, 2002;Keller and Hibst, 1992;Matsumoto et al, 2003).…”

“…The morphology of cavities prepared by different Er:YAG laser parameters (groups 1-8) demonstrated a conservative configuration, following the minimal intervention principles with strict removal of tissue and maximum maintenance of dental hard tissue, creating cavities appropriate for restoration using adhesive materials (Cozean and Powell, 1998;Den Besten et al, 2001;Hibst and Keller, 1992). On the other hand, cavities prepared by diamond burr in a conventional high-speed drill (group 9) showed a box-shaped configuration, with sharp cavo-surface edges and welldefined geometric internal angles, flat floor and walls cavity, with smear layer covering enamel and dentin surface in a typical morphological pattern ( Fig.…”

“…It is important to state that the use of Er:YAG laser to prepare cavities must be performed by trained professionals, with knowledge about laser safety, risks and damages, safety rules, interaction with tissues and parameters, and the operator has to consider the pulse width, optimum energy and repetition rate, and always choose the minimum fluency to promote effective and safe ablation of the target tissue (Dostalová et al, 1998;Fried et al, 2001;Hibst, 2002). In clinical practice, patients reported more comfort and acceptance of laser treatment due to decreased noise discomfort, no contact and vibration, minimal pain sensation and reduced need for local anesthesia, and reduction of psychological trauma and fear during dental appointment (Cozean and Powell, 1998;Den Besten et al, 2001;Hibst, 2002;Keller and Hibst, 1992;Matsumoto et al, 2003).…”

“…The Er:YAG laser wavelength exactly matches the absorption peak of water; in the process of this wavelength interaction with the hard tissue, the energy is converted into heat, leading to water vapor formation, which expands and produces high pressure inside the target tissue and induces instantaneous microexplosions and ejection of particles of tissue in a process called thermomechanical ablation (Fried et al, 2001;Hibst, 2002;Hibst and Keller, 1989;Keller and Hibst, 1989;Wigdor et al, 1993). This physical interaction of Er:YAG laser with the dental tissue has shown to be a promising and effective mechanism for selective ablation of carious and healthy enamel and dentin tissues, because of the different water and mineral compositions of these different substrates and different ablation threshold of hard tissues (Cozean and Powell, 1998;Matsumoto et al, 2003;Wigdor et al, 1995) In accordance with these new restorative management approaches, Er:YAG laser promotes minimal and conservative cavities for adhesive restorative materials (Hibst, 2002). The morphological analysis of dental hard tissues irradiated by the Er:YAG laser has shown no formation of smear layer, a microirregularity on enamel surface, with a honey-comb-like appearance; the dentin surface shows open dentinal tubules, an irregular and microretentive morphological pattern *Correspondence to: Prof. Carlos de Paula Eduardo, Departamento de Dentística, Faculdade de Odontologia, USP, Av.…”

Morphological analysis of cavities prepared by different parameters of Er:YAG laser

“…The morphology of cavities prepared by different Er:YAG laser parameters (groups 1 to 8) demonstrated that this laser cannot prepare box shaped cavities with a sharp line and defined internal angles, the laser cavities showed irregular and scaly cavo-surface edges, cavity floor and walls, no defined internal angles, with a conservative configuration, following the minimal intervention principles with strict removal of carious tissue and maximum maintenance of dental hard tissue, creating cavities appropriate for restoration using adhesive materials like composite resin, glass ionomer cement or compomers 9,11,15,19 ; Furthermore, Er:YAG laser promoted a thermal effect and bacterial reduction in irradiated dental hard tissue, Sharon-Buller et al 59 (2003), with regard to the possibility of maintaining infected carious tissue, more conservation of remaining dental hard tissues in cavity preparations and ART (atraumatic restorative treatment) and more reliability of restorative procedures.…”