Implant therapy is an effective and predictable method to replace missing teeth. Nevertheless, biological complications (peri-implant mucositis and peri-implantitis) due to the local inflammatory reaction of marginal soft tissues to the biofilm may happen. Different strategies in implant surface decontamination have been suggested to reduce the bacterial load and remove biofilm. However, none of these modalities has shown effectiveness in recovering peri-implant health, and there is no consensus on the best available treatment to provide satisfactory implant surface decontamination. Additional researches on the decontamination/detoxification of infected titanium surfaces are needed to identify an effective treatment.
The research project aims to compare, using an ex-vivo model, the efficacy of electrolytic decontamination (recently developed procedure) versus mechanical debridement with sodium bicarbonate and glycine powders and combined mechanical-electrolytic decontamination in the biofilm removal following surgical exposure of implants failed for severe peri-implantitis.
The study design is a single-blind, randomized, controlled, ex vivo investigation with intra-subject control.
Study participants are consecutive patients with at least 4 hopeless implants, in function for >12 months and with progressive bone loss exceeding 50%, which have to be explanted. Implants of each patient are randomly assigned to the untreated control group or one of the three decontamination procedures: electrolytic, mechanical or combined mechanical-electrolytic.
Following surgical exposure, implants selected as control are retrieved, and afterwards, test implants are decontaminated according to allocation and carefully explanted with a removal kit.
Microbiological analysis is expressed in colony-forming units (CFU/ml), and microbial identification is performed for each implant. Scanning electron microscope (SEM) images assess micromorphological surface changes after instrumentation.
Two are the strengths of the present project: to evaluate the effectiveness of an innovative electrolytic approach to biofilm removal after surgical exposure of implants failed for severe peri-implantitis and to use an ex vivo model.
The GalvoSurge® Dental Implant Cleaning System has been under development since 2012, and it became available only in 2019.
The Galvo Surge Dental Implant Cleaning System was developed to remove biofilm by flushing an electrolytic cleaning fluid around the implant in the patient's mouth. A safe extra-low voltage activates the liquid, and during this electrolytic process, the biofilm is removed even from areas of the implant that are difficult to access. The procedure is easy to perform, atraumatic and pain-free for the patient, time-efficient, with a treatment time of only two minutes per implant and maintain the implants surface integrity.
To date, there are only three studies in the literature (two in vitro and one clinical trial) on this promising decontamination method. Furthermore, all studies were sponsored by GalvoSurge Dental AG, and the authors own shares in GalvoSurge Dental AG.
Thus, an independent evaluation of the efficacy of an innovative electrolytic approach for removing actual and mature
biofilm from infected implant surfaces may contribute to advancing knowledge on decontamination methods to improve both non-surgical and surgical treatments of peri-implantitis. The topic of peri-implantitis is a major challenge in implant dentistry. Universities and researchers are currently involved in defining treatment protocols for implant care and long-term maintenance.
The ex-vivo study design allows overcoming some limitations of in vitro and animal studies and human clinical trials.
In in-vitro studies published, specimens (titanium discs, sheets, strips and cylinders) and biofilm contaminants (non-mineralized supragingival plaque, single-species biofilm, bacterial products, indelible non-covering ink) could not represent actual clinical situations. The use of custom-made defect models with different morphologies mimicking peri-implant defects is unable to simulate clinical settings. The cleaning efficacy of decontamination procedures is different, as the anatomical limitations of the oral cavity (e.g., the tongue) and the presence of blood and saliva hamper the accessibility to infected implant surfaces.
In animal studies, the main limitation is the difficulty to directly transfer therapeutic effects on peri-implant infection, which were on average better in animal models (mainly monkeys and dogs) than humans due to the difference in anatomical characteristics and physiological systems between the two species.
In human clinical trials, treatment outcomes are significantly influenced by patient¿s factors, such as the level of oral hygiene, peri-implant microbiota, prosthetic designs, immunocompetent characteristics, systemic conditions, history of periodontitis, and cigarette smoking. Further confounder factors are the absence of a true control group (untreated patients) for ethical reasons, the allocation of different types of implants in test and control groups, and clinical parameters instead of quantifying the residual biofilm in the treatment outcomes evaluation.
Other strength points of the project are the use of failed contaminated implants and not patients as statistical analysis unit, decontamination methods applied before the implants retrieval, untreated implants used as positive control tests, the intra-subject evaluation adopted to overcome the bias on treatment effects due to the implant design and surface, and patients factors.