Article

Feature Article
Abstract

Peri-implantitis is a biofilm-mediated inflammatory process that leads to soft- and hard-tissue breakdown. Peri-implant diseases are the most frequent biologic implant complication in daily practice. Certain systemic conditions as well as detrimental habits have been demonstrated to negatively impact peri-implant tissue health and stability. In addition, several local predisposing factors were also identified to be associated with the development of peri-implantitis, such as the lack of keratinized mucosa, residual cement or a micro-rough implant surface exposed to the oral cavity or the peri-implant sulcus. This clinical review paper will focus on the latter risk factor, which is often caused by poor surgical performance by the clinician during implant surgery.

Introduction

Based on more than 50 years of progress in material sciences and clinical protocols and experience, contemporary implant dentistry is nowadays conceived as a predictable and effective treatment modality for fully and partially edentulous patients (Buser et al. 2000). Several 10-year studies have demonstrated success and survival rates of around 95% (Albrektsson 2012). Similar outcomes have been reported in more complex scenarios such as immediate or early implant placement along with simultaneous bone augmentation procedures using guided bone regeneration (GBR) (Blanco et al. 2019; Chrcanovic et al. 2014; Graziani et al. 2019). Nonetheless, survival is not the only desired endpoint nowadays, but also the lack of technical/biological complications and patient satisfaction. 

Peri-implant biological complications (i.e. peri-implant diseases) are regarded as pathologic inflammatory entities in response to pus-forming bacteria (Fig. 1). The latest epidemiological reports indicate that they occur in 18.5% of patients, and in 12.8% of implants (Rakic et al. 2018). There is strong scientific evidence that there is an increased risk of developing peri-implantitis in patients who have a history of chronic periodontitis, poor plaque control, and/or no regular maintenance care after implant therapy; while conflicting data exists regarding the influence of smoking and hyperglycaemia (Schwarz et al 2018). Furthermore, current data suggests that other local factors may initiate the disease and may explain the site-specificity of the condition. As such, the presence of submucosal cement, the lack of peri-implant keratinized mucosa, the malpositioning of implants that make it difficult to perform oral hygiene and maintenance, as well as an exposed micro-rough implant surface to the peri-implant sulcus are highlighted as among the most notable local factors (Monje et al. 2019).

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Fig. 1: Scanning electron microscopy slide of an implant retrieved due to peri-implantitis showing granulation tissue and plaque attached to the implant surface

Jemt demonstrated in a large cohort of implant patients that one of the most critical factors in predicting therapeutic failure is the operator/surgeon involved in the surgical intervention (Fig. 2) (Jemt 2017). Similarly, Canullo et al. showed that, in the attempt to distinguish between different predictive profiles for patient-based risk assessment of peri-implantitis, 40.8% were associated with surgical risk factors. In particular, the odds ratio for developing peri-implantitis due to malposition was 48.2 (Canullo et al. 2016). This data was therefore in agreement with a survey study that illustrated that most implants diagnosed with peri-implantitis were associated with inadequate implant positioning (Monje et al. 2016). 

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Fig. 2a: Peri-implantitis has been associated with implant malposition as it favors an inadequate restoration that could lead to excessive bone resorption on the buccal aspect and to plaque accumulation attributed to an inadequate restorative emergence profile
Fig. 2b: Peri-implantitis has been associated with implant malposition as it favors an inadequate restoration that could lead to excessive bone resorption on the buccal aspect and to plaque accumulation attributed to an inadequate restorative emergence profile
Fig. 2c: Peri-implantitis has been associated with implant malposition as it favors an inadequate restoration that could lead to excessive bone resorption on the buccal aspect and to plaque accumulation attributed to an inadequate restorative emergence profile
Fig. 2a Fig. 2b Fig. 2c