Review study compares machined and sandblasted dental implant surfaces
BUDAPEST, Hungary: Studies have shown that the implant surface roughness influences the degree of biological integration and success rates of dental implants, which has resulted in a shift of focus from machined to roughened implant surfaces. However, clinicians have still been looking for strong scientific evidence that supports the use of sandblasted implants over machined ones in clinical practice. Looking at this need, the team of researchers from the Semmelweis University in Budapest, carried out a comparative evaluation of implant failure and marginal bone loss between the two types of surfaces.
Ever since it emerged that surface roughness greatly influences the degree of biological integration and success rates of dental implants, various surface modifications such as sandblasting, acid-etching, anodization, plasma-spraying, coating with different bioactive surfaces and the combination of these have come into practice.
Among all these methods, sandblasting was the earliest to be introduced, during which, ceramic particles such as titanium oxide, aluminium oxide or silica are blasted on to the implant surface. Two factors - the sand particle size and the speed with which they hit the implant surface – play a key role in influencing the implant surface roughness. Compared to the machined implants that have smoother surfaces with shallow grooves, the sandblasted ones demonstrate irregular, rough surfaces.
Studies have shown different results while demonstrating the effects of sandblasting on osseointegration, While several in vitro studies have demonstrated the positive effects of sandblasting on osseointegration, some preclinical and clinical studies have shown that moderately rough surfaces may not perform better.
These studies bring in a newer perspective to osseointegration by shifting the focus to the formation of biofilm. They suggest that a rougher surface may influence the process of biofilm formation, making it easier for the bacteria to attach to the implant surface. The bacterial biofilm renders the implants vulnerable to peri-implantitis, resulting in marginal bone loss around the rough surfaces.
The current study was a systematic review, which included seven studies, comparing 362 sandblasted surfaces with 360 machined ones. The results showed that after one year of use, the risk of failure among sandblasted surfaces was 80 per cent lower when compared to machined implants. When the effect of sandblasting was evaluated after five years, the risk of failure was 74 per cent lower in the sandblasted implant surfaces. However, when marginal bone loss was assessed, there was no significant difference between the two implant surfaces after one and five years of use.
The researchers concluded: “This meta-analysis reveals that sandblasting is superior over machined surface in implant failure but not in marginal bone level in healthy subjects. It also points out the need for further randomised clinical trials with large sample size for objective determination of the clinical benefits of certain implant surface modifications.”
The study was conducted in collaboration with the University of Pécs and the University of Szeged, both in Hungary.
The study, titled “Sandblasting reduces dental implant failure rate but not marginal bone level loss: A systematic review and meta-analysis”, was published online on 3 May 2019 in PLOS ONE.