Abstract
Background: The use of lasers has become increasingly common in the field of medicine and dentistry, and there is a growing need for a deeper understanding of the procedure and its effects on tissue. The aim of this study was to compare the erbium-doped yttrium aluminium garnet (Er:YAG) laser and conventional drilling techniques, by observing the effects on trabecular bone microarchitecture and the extent of thermal and mechanical damage. Methods: Ovine femoral heads were employed to mimic maxillofacial trabecular bone, and cylindrical osteotomies were generated to mimic implant bed preparation. Various laser parameters were tested, as well as a conventional dental drilling technique. The specimens were then subjected to micro-computed tomographic (μCT) histomorphometic analysis and histology. Results: Herein, we demonstrate that mCT measurements of trabecular porosity provide quantitative evidence that laser-mediated cutting preserves the trabecular architecture and reduces thermal and mechanical damage at the margins of the cut. We confirmed these observations with histological studies. In contrast with laser-mediated cutting, conventional drilling resulted in trabecular collapse, reduction of porosity at the margin of the cut and histological signs of thermal damage. Conclusions: This study has demonstrated, for the first time, that mCT and quantification of porosity at the margin of the cut provides a quantitative insight into damage caused by bone cutting techniques. We further show that with laser-mediated cutting, the marrow remains exposed to the margins of the cut, facilitating cellular infiltration and likely accelerating healing. However, with drilling, trabecular collapse and thermal damage is likely to delay healing by restricting the passage of cells to the site of injury and causing localized cell death.
Highlights
Since the pioneering work of Stern, Sognnaes and the Goldman brothers on the ruby laser in the 1960s, followed by the CO2 and Nd:YAG lasers in the 1980s (Coluzzi & Convissar, 2004; Featherstone & Nelson, 1987), and the erbium series of lasers in 1989 (Hibst & Keller, 1989), there has been considerable interest in the use of laser radiation for cutting of bone tissue, in the field of dentistry.Over the past ten years, the erbium-doped yttrium aluminium garnet (Er):YAG laser with a working wavelength of 2940 nm is one of the most commonly used in dentistry (Romanos, 2015)
Under the conditions of measurement described in the methods section, the negative control bone sample region of interest (ROI) had a mean porosity of 56% (Figure 2a)
When the experimental samples were measured, it was apparent that the hole generated by the conventional dental drill had a porosity significantly lower than the uncut control (p
Summary
Since the pioneering work of Stern, Sognnaes and the Goldman brothers on the ruby laser in the 1960s, followed by the CO2 and Nd:YAG lasers in the 1980s (Coluzzi & Convissar, 2004; Featherstone & Nelson, 1987), and the erbium series of lasers in 1989 (Hibst & Keller, 1989), there has been considerable interest in the use of laser radiation for cutting of bone tissue, in the field of dentistry.Over the past ten years, the Er:YAG laser with a working wavelength of 2940 nm is one of the most commonly used in dentistry (Romanos, 2015). Studies that address the microstructure of bone after exposure to laser radiation are qualitative To help address these concerns, we propose a method to quantitatively evaluate thermal and mechanical destruction of trabecular bone by cutting techniques, and ask definitively whether the Er:YAG laser causes less thermal tissue damage than conventional drilling techniques. Results: we demonstrate that mCT measurements of trabecular porosity provide quantitative evidence that laser-mediated cutting preserves the trabecular architecture and reduces thermal and mechanical damage at the margins of the cut. We confirmed these observations with histological studies. We further show that with laser-mediated cutting, the marrow remains exposed to the margins of the cut, facilitating cellular infiltration and likely accelerating version 1 published 17 Jul 2017
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
