HOLMIUM-YAG LASER-ABLATION CHARACTERISTICS IN CALVARIAL LAMELLAR AND CORTICAL BONE - THE ROLE OF WATER AND TISSUE MICROARCHITECTURE

Citation
Bjf. Wong et al., HOLMIUM-YAG LASER-ABLATION CHARACTERISTICS IN CALVARIAL LAMELLAR AND CORTICAL BONE - THE ROLE OF WATER AND TISSUE MICROARCHITECTURE, Lasers in medical science, 10(3), 1995, pp. 181-188
Citations number
29
Categorie Soggetti
Medical Laboratory Technology",Surgery
Journal title
ISSN journal
02688921
Volume
10
Issue
3
Year of publication
1995
Pages
181 - 188
Database
ISI
SICI code
0268-8921(1995)10:3<181:HLCICL>2.0.ZU;2-H
Abstract
The effect of tissue micro-architecture and water content on ablation rates in bone is examined. Precisely machined and prepared porcine cal varial lamellar and cortical bone were ablated with a Holmium-YAG lase r (lambda=2.1 mu m). Lamellar and cortical bone differ substantially i n their tissue micro-architecture. Both are porous hard tissues, which differ predominantly in size and distribution of pores within the bon e matrix. These hard tissues were ablated under physiological (wet) an d chemically dehydrated conditions. The ablation rates over the range of energy densities examined assumes many linear characteristics. Abla tion rate (as a function of fluence) is considerably higher for dehydr ated cortical bone (4.7 mu m cm(2) J(-1)) compared to fresh cortical b one (1.49 mu m cm(2) J(-1)). This trend is also observed in lamellar b one (2.31 mu m cm(2) J(-1) for wet and 0.37 mu m cm(2) J(-1) for dry). Under both physiological and dehydrated conditions, cortical bone was ablated faster. Mechanisms accounting for these observations are disc ussed.