###### Abstract
Other factors that have been suggested as risk factors for the onset and/or progression of peri-implant diseases are the absence of peri-implant keratinized mucosa (PIKM), occlusal overload, the presence of titanium particles within peri-implant tissues, bone compression necrosis, overheating, micromotion, or biocorrosion [15; 16]. Different therapies have been proposed for the treatment of peri-implantitis [17]. Most reports state that a non-surgical approach appears to be insufficient to solve this biological complication [18]. However, these conservative therapies can remove the oral biofilm, modify the risk indicators, and improve the peri-implant tissues prior to the surgical phase [19]. Surgical treatments appear to provide more promising outcomes. The type of surgical approach is usually determined by clinical factors like the peri-implant defect anatomy [20], the amount of keratinized mucosa, and the esthetic component [6]. In 2007, [PERSON] et al. [20] classified peri-implant defects into non-contained or suprabony defects (type II) or intraosseous defects (type I). Later, [PERSON] et al. [21] modified this classification to include the severity of the defect. These classifications are currently used for decision-making when performing surgical treatment. Most authors describe three major techniques: resective, reconstructive, and combined [6; 22; 23]. Resective approaches are used in uncontained defects with a suprabony component [24]. [PERSON] et al. [25; 26] introduced the concept of implantoplasty as an additional technique to improve the outcomes of resective surgeries. Additionally, [PERSON] et al. [27] emphasized that smoothing the implant surface enhances peri-implant tissue stability and promotes long-term maintenance. Resective approaches have been assessed in recent years, with acceptable results. However, recurrence of the disease occurs in 39-59.5% of the treated implants [28; 29; 30]. A reconstructive approach is usually indicated in self-containing defects that are usually found in the initial stages of peri-implantitis and seem to provide good results [18; 31]. Combined approaches have also been proposed, consisting of implantoplasty of the supraosseous portion of the defect and reconstruction of the infrabony portion using guided bone regeneration (GBR) techniques [32]. [PERSON] et al. [33] showed that combined surgery significantly decreased inflammation, probing depth (PD), and bleeding on probing (BOP). However, the treatment of peri-implantitis poses significant challenges, and postsurgical complications are common mostly due to the chronic inflammation of peri-implant tissues and the presence of biofilm. The recently published clinical guidelines for the prevention and treatment of peri-implant diseases by the European Federation of Periodontology [34] recommended the use of bone substitutes for reconstructive therapy, with no apparent differences between the different available materials. On the other hand, the use of membranes is a matter of debate, and the available evidence is still scarce to recommend the systematic use of these devices [31; 35]. Among the most common postoperative complications following the reconstructive treatments of implants with peri-implantitis are postoperative infections, wound dehiscence, and membrane or biomaterial exposures [36; 37]. Proper soft tissue healing is essential to ensure treatment success, preventing bacterial contamination and improving the esthetic outcomes [38]. A recent randomized clinical trial found a considerable incidence of complications in cases treated with a xenograft and a non-resorbable membrane, with 19% of patients presenting soft tissue dehiscence, 9.5% with membrane exposures, and 4.8% with bone substitute exposure [35]. However, the available data on this topic are still scarce. For this reason, a study with the aim of describing the main postoperative complications associated with reconstructive therapy of peri-implant bone defects in patients with peri-implantitis was performed.