Root analogue dental implant
[1] The basic principle of endosseous implants is a biological process described as osseointegration, in which materials such as titanium or ceramic form an intimate bond to bone.
[citation needed] Titanium screws are prone to peri-implantitis[5] and plaque accumulation, leading to further interventions.
Moreover, there are concerns over possible long-term corrosion and release of ions to the body environment, so researchers are evaluating non-metallic alternatives.
[10][5] Zirconium dioxide is doped with small amounts of yttria, which results in a material with superior thermal, mechanical, and electrical properties, and enhanced fracture toughness – ideal for surgical implants.
[11][12] Zirconia is metal free and is biocompatible, and has low bacterial affinity in comparison to regular titanium.
[5] An alternative technique uses a titanium root fused to a zirconia abutment by a sintering process that eliminates any possible microgap (which could cause peri-implantitis, leading to bone loss around the implant).
Those early attempts failed because of insufficient knowledge of healing of cortical and spongy bone, method, material, tooling, and technology.
Form alterations to the RAI, in conjunction with the pathology of patient, can only be carried out by a practitioner with the requisite knowledge, experience and skills.
In several instances implant insertion led to fractures of the thin buccal wall of the alveolar bone.
[28][29] A new attempt was made by Pirker et al 2004 in a human trial with root analogue zirconia implants, but this time by applying differentiated osseoingration on the surface.
[16] Mangano et al in Italy in 2012 reported the successful clinical use of a custom-made root analogue implant made by direct laser metal forming (DLMF) from a CBCT scan.
In contrast to conventional geometric implants, only a handful of scientific groups have carried out any work in this area since 1964.
[33] Several existing evaluation methods for conventional thread-type implants do not apply to RAIs because of their structural differences.
[5][13] While custom root analogue zirconia implants offer significant benefits over conventional titanium implants, and follow-up studies with patients show high success rates and satisfactory esthetic results,[5][18][20] further studies are needed to evaluate surface-bone interactions and mechanical behaviour of zirconia.
