Periodontology
Short description
The research field of periodontology embraces diseases and conditions in tissues surrounding teeth and dental implants. Periodontitis is a chronic inflammatory disease affecting the tooth-supporting apparatus. It is caused by bacteria and characterized by progressive loss of clinical attachment and supporting bone. Periodontitis is one of the most common human diseases and accounts for about 30 % of all tooth loss. Peri-implantitis is a plaque-associated pathological condition in tissues around dental implants. It is characterized by inflammation of the peri-implant mucosa and progressive loss of supporting bone.
Research activities has a translational and cross-disciplinary profile focusing on the etiology, pathogenesis and epidemiology of periodontal and peri-implant diseases, and methods on their prevention and treatment.
Periodontitis and peri-implantitis – human biopsy material
Peri-implantitis and periodontitis have many features in common. While both conditions are characterized by inflammation in adjacent tissues together with bone loss, peri-implantitis appears to progress faster and presents with a larger inflammatory cell infiltrate (ICT). The understanding of differences between peri-implantitis and periodontitis lesions in humans is fundamental in the improvement of measures for prevention and treatment of peri-implantitis.
Purpose
The aim of the current project is to study local host response characteristics in peri-implantitis and periodontitis in humans at the cellular level to explain differences in disease onset and progression. We have previously demonstrated critical differences between the two lesions in terms of size and cell composition. The continuing analyses will focus on the borderline between the lesion and the biofilm and epigenetic changes including DNA damage and repair in neutrophils and other cells.
Study population and methods
Patients with severe peri-implantitis (BoP, PPD ≥7 mm, bone loss >3 mm at ≥1 sites) and patients with severe periodontitis (BoP, PPD ≥7 mm, >50% bone loss at ≥4 sites) are included. Soft tissue biopsies from gingival and peri-implant tissues, about 3-4 mm wide and extending from the soft tissue margin to the bone crest, are collected following local anesthesia from diseased sites. The tissue samples are fixed in formalin and embedded in paraffin. Immunohistochemistry is used to determine differences in size and extension of ICT, cell phenotypes and functions.
Project Facts
Project Manager
Tord Berglundh
Funding
+ The Swedish Research Council (Vetenskapsrådet),
+ TUA
Collaboration
+ Folktandvården Västra Götalandsregionen
Reconstructive surgical therapy of peri-implantitis-related osseous defects - A multicenter randomized controlled clinical trial
Peri‐implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation (bleeding/suppuration on probing) in the peri‐implant connective tissue and progressive loss of supporting bone. The peri-implant osseous defects associated with the disease are typically crater-like and resemble angular bone defects at teeth. The goal of reconstructive treatment of peri-implantitis is to restore supporting tissues that were lost during disease progression (defect fill) and to preserve esthetics by preventing soft tissue recession.
Purpose
The objective of this multinational, multicenter randomized controlled trial is to evaluate the clinical efficacy of the use of a bone substitute material in reconstructive surgical therapy at peri-implantitis-associated osseous defects. Primary outcome is treatment success (absence of bleeding/suppuration on probing, probing pocket depth ≤5 mm & ≤1 mm recession of the mucosal margin). Secondary outcomes include radiographic defect fill and patient-related outcome variables.
Study population, design and treatment procedures
The project will be conducted as a two-armed RCT of 5-year duration at 7 European centers. 140 systemically healthy patients (age: ≥18 years) with at least one dental implant diagnosed with advanced peri-implantitis (probing pocket depth ≥7 mm, bleeding/suppuration on probing & bone loss ≥3 mm) will be enrolled. Surgical procedures will include flap elevation, removal of inflamed tissue and mechanical decontamination of implant surfaces. Following random allocation, osseous defects (≥3 mm deep & ≤4 mm wide) will be filled with a bone substitute material in the test group, while no material will be applied in the control group. Mucosal tissues will be sutured to their previous position. Clinical evaluations are performed at 6, 12, 24, 36, 48 and 60 months and radiographs will be obtained at 1-, 3- and 5-year examinations.
Project Facts
Project Managers
Tord Berglundh / Jan Derks
Funding
+ The Swedish Research Council (Vetenskapsrådet)
+ TUA
+ Osteology Foundation
Collaboration
+ Folktandvården Västra Götalandsregionen
+ Clinical Centers in Italy, Germany and Spain
Periodontitis and systemic disorders - Analyses based on large patient cohorts
Periodontitis is one of the most prevalent human diseases and its severe form affects about 10% of adults. The prevalence of diabetes in Sweden is approximately 5% but studies have also indicated that diabetes is more frequent among subjects affected by periodontitis than periodontally healthy individuals. Such findings were generally made in selected and small populations including patients diagnosed with type 2 diabetes. Similar evidence on type 1 diabetes is lacking.
Purpose
The overall objective of this project is to evaluate the association between systemic disorders (diabetes, atherosclerotic cardiovascular disease) and periodontitis using data from large patient cohorts. Based on two separate studies, the goal is to improve the understanding of the interplay between general and oral health and, thereby, improving medical/dental care for individuals at risk for or diagnosed with systemic disease.
Study population, design and methods
In a cross-sectional study based on a clinical examination of 400 adult individuals (age: 50-64 years) identified in the Gothenburg cohort of the Swedish CArdioPulmonary bioImage Study (SCAPIS; study population n=6,500) we plan to evaluate the association between periodontitis and risk for cardiovascular events. Patient groups with and without coronary atherosclerotic plaque as confirmed through computed tomography will be invited for assessment of their oral/periodontal status. In a second study, we plan to match several national registries to explore the potentially bi-directional link between diabetes and periodontitis. The Swedish quality registry for caries and periodontal disease (SKaPa) contains data with a high level of completeness from 2010 and onwards and >4 million adults are currently included. The Swedish National Diabetes Register (NDR) also has a high level of completeness, representing >90% of all individuals with diabetes in Sweden. By matching the two registries (SKaPa & NDR) and evaluating longitudinal data (2010-2020) we plan to evaluate the potential association between periodontitis and diabetes, the potential chronological association and the potential effect of periodontal treatment on glycemic control. All evaluations will be adjusted for possible confounding factors (e.g. socioeconomic status, diseases of the circulatory system, cancer) retrieved from five additional national registries.
Project Facts
Project Manager
Jan Derks
Funding
+ TUA
+ Eklund Foundation
Collaboration
+ Institute of Medicine (The Sahlgrenska Academy)
+ The Swedish National Diabetes Register
Periodontal infection control - studies on effectiveness (The VG-perio project)
Periodontitis affects about 40% of adults in Sweden and costs for prevention and treatment are high. Methods aiming at improving cost-effectiveness of periodontal care are therefore of great importance. Although prevention and treatment of periodontitis are predominantly performed in general practice, representative data on treatment outcomes are lacking. Thus, studies evaluating effectiveness, i.e. care provided to the general population under conditions found in practice, are of high priority.
Purpose
The present series of studies is designed to improve the understanding on the effectiveness of non-surgical periodontal therapy. Approaches include (i) the analysis of data from the national quality register for caries and periodontal disease (SKaPa) regarding diagnosis and treatment of periodontitis, treatment outcomes and potential inequalities in care and (ii) in a quasi-randomized controlled prospective field study comparing the treatment concept “Guided periodontal infection control” (GPIC) with traditional treatment of periodontitis.
Study population, design and methods
Data on 378,000 adult individuals from the SKaPa register will be analyzed regarding diagnosis and treatment of periodontitis, treatment outcomes and potential inequalities in periodontal care. The prospective field study includes 90 dental hygienists and 800 patients at 40 clinics in general practice. The studies have a patient-centered and health-economic focus and multilevel analyzes will be used to identify factors important for care management (prevention, diagnosis and treatment) and treatment outcomes. The project is expected to generate data that are relevant for policy makers in the planning and utilization of available resources for the future periodontal care.
Project Facts
Project Managers
Maria Welander / Kajsa Henning-Abrahamsson
Funding
+ FORTE
+ TUA
+ FoU-grants VGR
Collaboration
+ Folktandvården Västra Götalandsregionen
Decontamination of implant surfaces in the treatment of peri-implantitis
Peri-implantitis is a pathological condition occurring in tissues around dental implants. It is characterized by inflammation and a subsequent loss of supporting bone. Clinical signs of peri-implantitis include visible signs of inflammation, bleeding on probing, increased pocket depth and bone loss. Treatment of peri-implantitis often involves surgical exposure of contaminated implant surfaces together with mechanical and/or chemical methods to eliminate the bacterial biofilm. The decontamination methods may, in addition, induce alterations of the implant surface characteristics that potentially affect cell attachment during wound healing. Surface alterations of an implant surface on the nano-topographical level may also promote changes in the genetic material of attaching cells through epigenetic mechanisms, i.e. changes in gene expression not encoded in the DNA sequence. Such mechanisms regulate cellular functions and differentiation of cells in contact with the material.
Purpose
The aim of this project is to (i) evaluate different mechanical and chemical decontamination methods in the removal of biofilm from the implant surface and (ii) to study the effect of the decontamination procedures on cellular functions including changes in the epigenetic pattern and the ability to attach to the implant surface.
Experimental design and methods:
The project consists of a series of in vitro studies on decontamination procedures of biofilm-contaminated titanium discs (10 x 10 mm) with two different surface topographies. Mechanical treatment will include the use of rotating titanium brushes, ultrasonic or air-polishing devices, while chemical treatment will be performed using different antiseptic solutions. The titanium discs will be examined using light microscopy and scanning electron microscopy to analyze the presence of residual bacteria after treatment. Osteoblast cells will be grown on the decontaminated discs and the ability of the cells to attach to the surface will be assessed by confocal laser scanning microscopy. Real time PCR molecular technique will be used to analyze genetic and epigenetic expression patterns. Decontamination methods with superior results regarding bacteria removal and biocompatibility will be further evaluated in an ex-vivo study on failed implants retrieved from patients with peri-implantitis.
Project Facts
Project Managers
Lena Larsson / Tord Berglundh
Funding
+ The Swedish Research Council (Vetenskapsrådet)
+ TUA
+ Patentmedelsfonden
Collaboration
+ University of Madrid, Spain