Biochemical and morphological analysis of dentin following selective caries removal with a fluorescence-controlled Er:YAG laser.

摘要

BACKGROUND AND OBJECTIVE: We evaluated the endpoint of caries removal with a novel fluorescence-controlled Er:YAG laser by biochemical analysis of dentin collagen and electron microscopy. MATERIALS AND METHODS: For the biochemical analysis 210 carious and 60 caries-free teeth were treated by a fluoresence controlled Er:YAG laser (n = 240) or by conventional drilling (n = 30). A layer of dentin from the cavity floor was removed to determine collagen crosslinks hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) by HPLC. Thirty teeth were examined by SEM and TEM. RESULTS: Approximately 100% HP and LP were found in carious dentin, in contrast to 0.33% (HP) and 0.68% (LP) in sound dentin. Following caries removal by laser 0.84% (HP) and 1.26% (LP) and 1.56% (HP) and 2.48% (LP) (threshold level 5, respectively 10) were found. CONCLUSION: The biochemical and ultrastructural analysis demonstrated the suitability of the fluorescence controlled Er:YAG laser to remove irreversibly denatured collagen of carious dentin. Lesers Surg. Med. 40:350-357, 2008. (c) 2008 Wiley-Liss, Inc.