Diederik Hentenaar

13 General introduction London 2019). In terms of proper restorative prosthetic design, it is recommended that implant suprastructures should be designed in such a way that oral hygiene measures can be performed effectively, plaque accumulation is prevented and implants are accessible for probing (Serino & Ström 2009). An over-contoured prosthetic design may limit the effect of peri-implantitis treatment modalities. To date, prosthetically focused studies mainly concern aesthetic outcome (Barwacz et al. 2018, Esposito et al. 2018, Linkevicius et al. 2015). However, the ideal crown contour in terms of emergence angle and emergence profile with respect to preserving marginal bone level and peri-implant soft tissue health remains unclear. Biomarkers in per-implant disease diagnosis The host inflammatory response to the microbial challenge may induce specific inflammatory responses/signatures around dental implants. During the active state of disease, inflammatory markers such as cytokines, proteinases and local tissue- degradation products are released into the peri-implant crevicular fluid (PICF) (Carinci et al. 2019). It is thought that these biomarkers could serve as adjunctive parameters to ameliorate the diagnosis and management of peri-implant disease and help to differentiate between different conditions of peri-implant health (Ramseier et al. 2009, Sexton et al. 2011, Syndergaard et al. 2014, Kinney et al. 2014, Carinci et al. 2019). Since traditional clinical diagnostic methods, such as bleeding on probing, pocket depth measurement, and radiographic assessment seem to exert a weak sensitivity/specificity to diagnose peri-implant disease, identifying potential markers seems necessary (Heitz- Mayfield 2008, Hashim et al. 2018, Monje et al. 2018, Monje et al. 2020). To date, most studies have focused on a limited number of biomarkers, including pro-inflammatory cytokines such as interleukin-1β, tumor necrosis factor-α and/or interleukin-6 (Alassy et al. 2019). Studies on potential important anti-inflammatory biomarkers, collagen degradation enzymes, osteoclastogenesis-related cytokines and chemokines to diagnose peri-implant health, have however never been properly performed (Duarte et al. 2016). Hence, whether biomarkers in PICF could potentially flank clinical and radiographical examination in monitoring peri-implant tissue health remains to be established. THERAPY The primary goal of peri-implantitis treatment is to re-establish and maintain a long- term state of peri-implant health. Ideally, complete resolution of disease should be attained in combination with bone and soft tissue regeneration and re-integration on the implant surface. An important step believed to successfully resolve peri-implantitis is to efficiently decontaminate the implant surface and/or debride the peri-implant area 1