Long-term surface success
Long-term clinical outcome of implants with different surface modifications. (Wennerberg et al., Eur J Oral Implantol. 2018)
Implant surface properties play an important role in osseointegration of dental implants. In this systematic review, Wennerberg and colleagues analyzed implant survival rate and marginal bone loss associated with different implant surfaces in 62 long-term studies with a minimum 10-year follow-up.
Reported implant survival rates ranged from 82.9–100% for all surfaces analyzed. In head-to-head comparisons, the anodized surface was associated with a significantly higher implant survival rate versus all other surfaces. The implant survival rate was highest for anodized (98.5%), compared with sandblasted/acid-etched (96.7%), turned (96.4%) titanium plasma-sprayed (96.1%), and sandblasted (94.8%). Average marginal bone loss was <2 mm for all surfaces evaluated. These results from long-term studies are consistent with previous findings showing anodized surfaces are associated with a high probability of implant survival and predictable long-term outcomes. Read more
Definitive abutment benefits
Definitive abutments placed at implant insertion and never removed: Is it an effective approach? A systematic review and meta-analysis of randomized controlled trials. (Tallarico et al., J Oral Maxillofac Surg. 2018)
Definitive abutment placement at time of implant insertion is associated with less peri-implant marginal bone loss and less buccal recession compared with provisional abutment placement; however, few long-term studies have examined the two approaches. In this systemic review, Tallarico and colleagues assessed outcomes associated with abutment placement protocols in 14 studies that included a minimum 1-year follow-up.
Marginal bone loss was significantly lower in the definitive abutment group versus the provisional abutment group (difference: 0.279 mm; P = 0.000). Buccal recession was also significantly lower (difference: 0.198 mm; P = 0.0004). Pink esthetic scores, as well as the incidence of prosthesis failure and complications, did not differ between the groups. The authors conclude that definitive abutment placement may be an important strategy for preserving peri-implant hard and soft tissue. Read more
Drilling influences zone of death
A comparative assessment of implant site viability in humans and rats. (Chen et al., J Dent Res. 2018)
The cutting of living bone by high-speed drilling has important biological consequences that are have only been partially characterized. Chen and coworkers used an established rodent model to investigate the effects of bone cutting methods on osteocyte viability and new bone growth following osteotomy. They also included comparisons with bone biopsies from patients.
Molecular, cellular, and histologic analyses demonstrated a close alignment between the responses of rodent and human alveolar bone to implant site preparation. In both rodents and humans, a radial zone of dead and dying osteocytes was observed surrounding the osteotomy site, with the greatest cell death occurring nearest the drill tip. Mapping this zone of death to temperature data showed that temperatures above 42°C were associated with osteocyte apoptosis. These observations show how well-designed animal models can facilitate understanding of how osteotomy site preparation affects bone health, and that new procedures can be improved by minimizing the zone of death. Read more