Dental endosseous implants in the medically compromised patient

The literature contains numerous observations on the significance of systemic disorders as contraindications to dental endosseous implant treatment, but the justification for these statements is often apparently allegorical. Although implants are increasingly used in healthy patients, their appropriateness in medically compromised patients is less equivocal. Perhaps surprisingly, the evidence of their efficacy in these groups of patients is quite sparse. Indeed, there are few if any randomized controlled trials (RCTs) in this field. Furthermore, any health risks from the placement of implants are unclear. We review the current evidence for the risks associated with endosseous implants in a range of systemic disorders. There is clearly a need for prospective systematic trials. The degree of disease-control may be far more important that the nature of the disorder itself, and individualized assessment, including the medical condition, quality of life and life expectancy is indicated. The benefits of implants to many of these patients may outweigh any risks. However, proper informed consent is mandatory.

Adhesion of bone cells to ion-implanted titanium

The use of ion-implantation to encourage osseointegration has been investigated using an in vitro model cell culture system and surface analysis. Polished titanium discs were implanted with calcium, potassium and argon ions. The adhesion of bone-derived cells was measured using radioactively labeled cells and the morphology examined using scanning electron microscopy. Similar numbers of cells were found to adhere to the potassium and argon-implanted titanium as to control (non-implanted) titanium. However, adhesion to the calcium-implanted titanium discs was significantly reduced. Moreover, although the cells were found to be well spread on the calcium and potassium-implanted titanium, a much greater proportion of cells appeared to remain rounded and poorly attached on the argon-implanted surface. These differences are discussed in relation to the observed surface roughness and chemistry, which were assessed using interferometry and X-ray photoelectron spectroscopy, respectively.