OBJECTIVE: The aim of this study is to elucidate the structure of the resin-dentin interface formed by photochemical dentin treatment using an argon fluoride (ArF) excimer laser. BACKGROUND DATA: The ArF excimer laser processes material by photochemical reaction without generating heat, while also providing surface conditioning that enhances material adhesion. In the case of bonding between resin and dentin, we demonstrated in a previous study that laser etching using an ArF excimer laser produced bonding strength comparable to that of the traditional bonding process; however, conditions of the bonding interface have not been fully investigated. METHODS: A dentin surface was irradiated in air with an ArF excimer laser followed by bonding treatment. Cross sections were observed under light microscope, transmission electron microscope (TEM), and scanning electron microscope, then analyzed using an energy dispersive X-ray spectroscope (EDS): EDS line profiles of the elements C, O, Si, Cl, P, and Ca at the resin-dentin interface were obtained. RESULTS: The density of C in resin decreased as it approached the interface, reaching its lowest level within the dentin at a depth of 2 μm from the resin-dentin interface on EDS. There was no hybrid layer observed at the interface on TEM. Therefore, it was suggested that the resin monomer infiltrated into the microspaces produced on the dentin surface by laser abrasion. CONCLUSIONS: The monomer infiltration without hybrid layer is thought to be the adhesion mechanism after laser etching. Therefore, the photochemical processes at the bonding interface achieved using the ArF excimer laser has great potential to be developed into a new bonding system in dentistry.
OBJECTIVE: The aim of this study is to elucidate the structure of the resin-dentin interface formed by photochemical dentin treatment using an argon fluoride (ArF) excimer laser. BACKGROUND DATA: The ArF excimer laser processes material by photochemical reaction without generating heat, while also providing surface conditioning that enhances material adhesion. In the case of bonding between resin and dentin, we demonstrated in a previous study that laser etching using an ArF excimer laser produced bonding strength comparable to that of the traditional bonding process; however, conditions of the bonding interface have not been fully investigated. METHODS: A dentin surface was irradiated in air with an ArF excimer laser followed by bonding treatment. Cross sections were observed under light microscope, transmission electron microscope (TEM), and scanning electron microscope, then analyzed using an energy dispersive X-ray spectroscope (EDS): EDS line profiles of the elements C, O, Si, Cl, P, and Ca at the resin-dentin interface were obtained. RESULTS: The density of C in resin decreased as it approached the interface, reaching its lowest level within the dentin at a depth of 2 μm from the resin-dentin interface on EDS. There was no hybrid layer observed at the interface on TEM. Therefore, it was suggested that the resin monomer infiltrated into the microspaces produced on the dentin surface by laser abrasion. CONCLUSIONS: The monomer infiltration without hybrid layer is thought to be the adhesion mechanism after laser etching. Therefore, the photochemical processes at the bonding interface achieved using the ArF excimer laser has great potential to be developed into a new bonding system in dentistry.
Authors: Simone G Moretto; Nilton Azambuja; Victor E Arana-Chavez; Andre F Reis; Marcelo Giannini; Carlos de P Eduardo; Patricia M De Freitas Journal: Microsc Res Tech Date: 2010-10-13 Impact factor: 2.769
Authors: Pietro Suppa; Lorenzo Breschi; Alessandra Ruggeri; Giovanni Mazzotti; Carlo Prati; Stefano Chersoni; Roberto Di Lenarda; David H Pashley; Franklin R Tay Journal: J Biomed Mater Res B Appl Biomater Date: 2005-04 Impact factor: 3.368
Authors: S Inoue; K Koshiro; Y Yoshida; J De Munck; K Nagakane; K Suzuki; H Sano; B Van Meerbeek Journal: J Dent Res Date: 2005-12 Impact factor: 6.116
Authors: Toru Nikaido; Dinesh D S Weerasinghe; Kanchana Waidyasekera; Go Inoue; Richard M Foxton; Junji Tagami Journal: Biomed Mater Eng Date: 2009 Impact factor: 1.300