Treatment of peri-implant diseases: a review of the literature and protocol proposal

Over the last two decades, the use of dental implants has become a common treatment option for the replacement of missing teeth. Industry predictions suggest that over 200,000 implants will be placed in the UK in 2013. With the increasing utilization of this treatment option, the frequency with which operators can expect to encounter biological complications increases. Peri-implant disease is a collective term for the inflammatory reactions of tissues surrounding implants, encompassing two main entities: peri-implant mucositis and peri-implantitis. Originally, up to 0.2 mm of bone loss around implants in the first year, then 0.1 mm per year subsequently, was deemed within acceptable limits.1 However, as techniques improve, less bone loss is expected.2 Bone loss exceeding acceptable limits threatens implant success and therefore requires intervention.

Peri-implant mucositis describes inflammation in the mucosa at an implant area with no signs of loss of supporting bone.3 Diagnosis of peri-implant mucositis is usually by detection of bleeding on probing (BOP), though redness and swelling may also occur (Figure 1a). Peri-implantitis, on the other hand, describes the presence of inflammation in the mucosa at an (osseo-integrated) implant with loss of supporting bone after one year in function. Diagnosis of peri-implantitis is based on increased probing pocket depths (BOP), suppuration (SUP)(Figure 1b), loss of supporting bone, visible clinically on reflection of the soft tissue for surgical treatment (Figure 1c) but usually evidenced radiographically (Figure 1d) and, infrequently, implant mobility is clinically detectable.3 The extent of peri-implant disease may be graded, grade 0, 1, 2 or 3 (Table 1). A more recently described, possibly different disease, ‘retrograde peri-implantitis’ is diagnosed as a symptomatic periapical lesion, which may demonstrate a draining sinus. Radiographically, a periapical radiolucency may be seen, with normal osseointegration of the coronal portion of the implant (Figure 2). This lesion often develops shortly after implant insertion and, in the majority of the cases, requires surgical treatment, the discussion of which is beyond the scope of this paper.4