QUESTION: What does the latest research say about the safety and efficacy of scaling dental implants?
ANSWER: Scratched implant surfaces are thought to be more susceptible to plaque biofilm accumulation, as well as more difficult to keep clean. The therapeutic concern is that scratched implant surfaces may increase the likelihood or severity of peri-implant mucositis or peri-implant bone loss. The literature has thus far failed to confirm this theory. Most of the research on this topic consists of in vitro studies that found metal scalers and ultrasonic inserts/tips (UITs) tend to scratch implant surfaces, whereas plastic-covered hand instruments and UITs do not.
In vitro research describes the potential risk for the deposition of shredded plastic from plastic-covered instruments onto rough-surface implant surfaces. In addition, research has indicated sodium bicarbonatebased powders used with air polishing devices may become embedded in rough-surface implant surfaces.2 It has also been reported that water-soluble glycine powder used in specially designed air polishing devices has only small effects on implant surface topography. Another in vitro study assessed the effects of instrumentation on manufactured rough-surface implants and found that the metal instrumentation of these fixtures resulted in a smoother implant surface and less bacterial adherence. Because most implants are rough-surface implants, this result may be positive, but it has yet to be evaluated in vivo.
A classification system for implant maintenance describes three categories of maintenance. Class I indicates no exposure of the implant and limited or no clinical access to the titanium abutment. Class II means the titanium abutment is exposed to the oral cavity or the gingival tissues easily move away from the abutment. In Class III cases, the implant is clinically exposed or a soft tissue pocket is adjacent to the implant fixture. In Class I cases, the clinician is only instrumenting the prosthesis, so the recommendation is to use conventional instrumentation. Be practical—metal curets and/or metal UITs remove calculus, but plastic instruments may not. For implants in Class II, hard accretions and soft plaque on the prosthesis should be removed with conventional instrumentation. The exposed abutment is smooth so plastic instruments are appropriate to remove soft plaque. If calculus is present on an exposed abutment, however, consider using metal instrumentation and/or air polishing. As previously stated, there is no existing evidence that scratched abutments result in increased inflammation or aggravate peri-implantitis.
In Class III situations, first determine if the implant is a smooth-surface implant or a rough-surface implant. Take into account whether deintegration or incomplete osseointegration has re sulted in thread exposure. Because plastic curets are not effective in debriding rough-surface implants, metal hand or ultrasonic instrumentation should be used. Furthermore, plasticcoated UITs may shred as they touch sharp fixture threads, leaving shards of plastic in the pocket.
Finally, if cleaning the portion of an implant designed to be osseointegrated, the possibility of scratching the implant surface is less important than the need to remove as much plaque and calculus as possible. This will reduce the likelihood of continued peri-implant bone loss.