Background: The erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser has been shown to be a promising tool for root treatment in periodontitis, but little information is available regarding the surface characteristics after this treat- ment, mainly because it is difficult to obtain standardized den- tin samples for in vitro studies. Methods: Commercially available standardized dentin disks were treated with an Er:YAG laser at different settings and used as a substrate for human primary osteoblastic cells (hOBs) and periodontal ligament fibroblasts (PLFs). Cell proliferation on untreated dentin was measured by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after 3, 6, 12, 24, and 48 hours of culture. The effects of the laser on dentin and cell morphology on treated and untreated samples were investigated by scanning electron microscopy after 3, 6, 24, and 48 hours of culture. Results: Dentin samples supported proliferation for both cell types, although growth kinetics were different. The laser dra- matically affected the dentin profile, creating a rough and irreg- ular surface. Cells grew easily on untreated dentin, but fewer cells were present on treated areas, often displaying long filo- podes. hOBs showed poorer adhesion to treated dentin than PLFs. Conclusions: The dentin disks provide a standardized and useful tool to study dentin surface modifications in vitro. PLFs behaved differently from hOBs on dentin, possibly because of their different affinity to this tissue and/or their differentiation state. The changes induced by the laser produced a less favor- able environment for cell adhesion or growth, and treated den- tin seemed to be more suitable for PLF adhesion compared to hOB adhesion. J Periodontol 2009;80:1648-1654.
Effect of laser- induced dentin modification on periodontal fibrobasts and osteoblasts: a new in vitro model / C. Galli; G. Passeri; A. Cacchioli; G. Gualini; F. Ravanetti; E. Elezi; G.M. Macaluso. - In: JOURNAL OF PERIODONTOLOGY. - ISSN 0022-3492. - 80(2009), pp. 1648-1654. [10.1902/jop.2009.090152]