Dealing with complications

Regeneration in periodontics refers to obtaining new periodontal attachment. With regard to peri-implantitis (PI), regeneration means re-osseointegration (i.e. new direct contact of bone tissue to a previously contaminated titanium surface). As osseointegration is assessed histologically, it cannot be part of clinical evaluations and goals. Rather than talking about ‘regenerative’ approaches we should instead talk about ‘reconstructive’ approaches.

When can we use a reconstructive instead of a resective approach?

There are many cases (especially in the aesthetic area) where we would like to prevent soft tissue recession. In a corresponding scenario in the periodontal patient, a reconstructive approach would be selected; with PI it is similar. We want to minimise soft tissue recession, which is what the patient is looking for, and this means a happier patient in the end.

The speaker explained that healing is strongly influenced by implant surface characteristics, while the superiority of any grafting material remains to be demonstrated.

In a recent experimental study on the surgical therapy of peri-implantitis (Almohandes et al., 2019), significantly better healing was observed at implants with a relatively smooth surface compared to those with a moderately rough surface. The type of bone substitute used was not associated with additional benefits; the use (or not) of a membrane also made no difference. The pronounced influence of surface roughness may have been due to the greater ability for the smooth surface to be cleaned and decontaminated.

Is there evidence supporting the use of grafting materials vs open flap debridement in PI treatment?

A recent systematic review and meta-analysis could only include three controlled studies (Tomasi et al., 2019). No differences were found with regard to improvement of inflammatory parameters, but the scarcity of data made it hard to draw conclusions, especially when only radiographic levels were measured; and no study addressed either recession or patient-reported outcome measures (PROMs). Hence, evidence is currently lacking on improved aesthetic outcomes or PROMs following reconstructive therapy compared with open flap debridement. It is clear that recession should be assessed as an additional outcome measure in future studies. Soft tissue levels should be evaluated as outcomes after PI treatment.

Is there a superior decontamination method to use?

Although evidence is still limited, the speaker stated that the decontamination protocol used in an ongoing multicentre study comparing the addition or not of a xenograft (ClinicalTrial.gov, NCT03077061) appears superior to other alternatives. The protocol does not include implantoplasty, but uses titanium brushes in an effort to decontaminate but not destroy the implant surface, as a recent in vitro study has shown (Cha et al., 2019). This suggested protocol has been shown to be effective as concluded by an RCT (de Tapia et al., 2019).