Influence of Removing or Leaving the Prosthesis after Regenerative Surgery in Peri-Implant Defects: Retrospective Study: 32 Clinical Cases with 2 to 8 Years of Follow-Up

Selecting biomaterials in the reconstructive therapy of peri-implantitis

Peri-implantitis is a pathogenic inflammatory condition characterized by progressive bone loss and clinical inflammation that may compromise the stability of dental implants. Therapeutic modalities have been advocated to arrest the disorder and to establish peri-implant health. Reconstructive therapy is indicated for bone defects exhibiting contained/angular components. This therapeutic modality is based upon the application of the biological and technical principles of periodontal regeneration. Nonetheless, the comparative efficacy of reconstructive therapy and nonreconstructive modalities remains unclear. Therefore, the aim of this narrative review is to address major clinical concerns regarding the efficacy, effectiveness, and feasibility of using biomaterials in peri-implantitis therapy. In particular, the use of bone grafting materials, barrier membranes, and biologics is comprehensively explored.

Antibacterial and Anti-Inflammatory Properties of Peptide KN-17

Peri-implantitis, an infectious disease originating from dental biofilm that forms around dental implants, which causes the loss of both osseointegration and bone tissue. KN-17, a truncated cecropin B peptide, demonstrated efficacy against certain bacterial strains associated with peri-implantitis. This study aimed to assess the antibacterial and anti-inflammatory properties and mechanisms of KN-17. The effects of KN-17 on oral pathogenic bacteria were assessed by measuring its minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Moreover, the cytotoxicity and anti-inflammatory effects of KN-17 were evaluated. KN-17 inhibited the growth of Streptococcus gordonii and Fusobacterium nucleatum during in vitro biofilm formation and possessed low toxicity to hBMSCs cells. KN-17 also caused RAW264.7 macrophages to transform from M1 to M2 by downregulating pro-inflammatory and upregulating anti-inflammatory factors. It inhibited the NF-κB signaling pathway by reducing IκBα and P65 protein phosphorylation while promoting IκBα degradation and nuclear P65 translocation. KN-17 might be an efficacious prophylaxis against peri-implant inflammation.

Minimal invasiveness in the reconstructive treatment of peri-implantitis defects

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, clinically characterized by increased peri-implant probing pocket depth and progressive loss of supporting bone. Consequently, to arrest further disease progression and to increase the chance to obtain re-osseointegration, surgical reconstructive procedures have been adopted. In particular, following a paradigm gathered from periodontal therapy, recent protocols have underlined the importance of a minimally invasive approach to optimize the outcomes of therapy while minimizing the risks of postoperative complications. The present review summarizes the level of evidence on the surgical reconstructive protocols focusing on the new approaches aiming to minimize surgical trauma and patients' postoperative discomfort, underlining the pros and cons of each treatment modality.

Incidence of Peri-Implantitis and Relationship with Different Conditions: A Retrospective Study

Articles on the prevalence of peri-implant diseases showed that 90% of peri-implant tissues had some form of inflammatory response and a prevalence of peri-implantitis from 28% to 51% according to various publications. Objective: To provide an overview of how risk factors can be related with peri-implantitis. Methods: A retrospective longitudinal study including 555 implants placed in 132 patients was evaluated based on the presence of peri-implantitis following the criteria of Renvert et al. 2018. Results: In total, 21 patients (15.9%) suffered peri-implantitis (PPG) and 111 patients (84.1%) did not suffer peri-implantitis (NPG). The results reveal that smokers have a high incidence of peri-implantitis (72.7%) compared to non-smokers (27.3%) (p < 0.0005). Another variable with significant results (p < 0.01) was periodontitis: 50% PPG and 23.9% NPG suffered advanced periodontitis. Systemic diseases such as arterial hypertension, diabetes mellitus, osteoporosis, and cardiovascular diseases do not show a statistically significant influence on the incidence of peri-implantitis. Patients who did not attend their maintenance therapy appointment had an incidence of peri-implantitis of 61.4%, compared to 27.3% in those who attend (p < 0.0001). From the results obtained, we can conclude that relevant factors affect peri-implantitis, such as tobacco habits, moderate and severe periodontitis, and attendance in maintenance therapy.