Peri-implantitis Disease Research Articles

The Oral Microbiome of Peri-Implant Health and Disease: A Narrative Review.

Peri-implantitis disease has increased significantly over the last years, resulting in increased failure of implants. Many factors may play a role in implant complications and failure, including ones related to the oral microbiota. This literature review aims to summarize the current knowledge of microbiome of implants in health and disease, focusing not only on the presence/absence of specific microbiota or on their relative abundance, but also on their phenotypic expression and their complex relationships with the host. The authors examined the MEDLINE database and identified key topics about peri-implant oral microbiome in health and disease. The peri-implant microbiome differs from that of the tooth, both in health and disease, as they are structurally and chemically different. The adhesion and formation of the peri-implant biofilm can be affected by the surface energy, topography, wettability, and electrochemical charges of the implant surface. In addition, the morphogenesis of the tissues surrounding the dental implant also differs from the tooth, making the dental implant more susceptible to bacterial infection. This interplay between the microbiome and the host immune system in peri-implant infections still needs to be elucidated.

Osteoblastic and Bacterial Response of Hybrid Dental Implants.

Bacterial infections in dental implants generate peri-implantitis disease that causes bone loss and the mobility of the dental implant. It is well known that specific ranges of roughness favor the proliferation of bacteria, and it is for this reason that new dental implants called hybrids have appeared. These implants have a smooth area in the coronal part and a rough surface in the apical part. The objective of this research is the physico-chemical characterization of the surface and the osteoblastic and microbiological behavior. One-hundred and eighty discs of titanium grade 3 with three different surfaces (smooth, smooth-rough, and completely rough) were studied. The roughness was determined by white light interferometry, and the wettability and surface energy by the sessile drop technique and the application of Owens and Wendt equations. Human osteoblast SaOS-2 was cultured to determine cell adhesion, proliferation, and differentiation. Microbiological studies were performed with two common bacterial strains in oral infection, E. faecalis and S. gordonii, at different times of culture. The roughness obtained for the smooth surface was Sa = 0.23 and for the rough surface it was 1.98 μm. The contact angles were more hydrophilic for the smooth surface (61.2°) than for the rough surface (76.1°). However, the surface energy was lower for the rough surface (22.70 mJ/m2) in both its dispersive and polar components than the smooth surface (41.77 mJ/m2). Cellular activity in adhesion, proliferation, and differentiation was much higher on rough surfaces than on smooth surfaces. After 6 h of incubation, the osteoblast number in rough surfaces was more than 32% higher in relation to the smooth surface. The cell area in smooth surfaces was higher than rough surfaces. The proliferation increased and the alkaline phosphatase presented a maximum after 14 days, with the mineral content of the cells being higher in rough surfaces. In addition, the rough surfaces showed greater bacterial proliferation at the times studied and in the two strains used. Hybrid implants sacrifice the good osteoblast behavior of the coronal part of the implant in order to obstruct bacterial adhesion. The following fact should be considered by clinicians: there is a possible loss of bone fixation when preventing peri-implantitis.

Current Molecular, Cellular and Genetic Aspects of Peri-Implantitis Disease: A Narrative Review

(1) Background: Peri-implantitis is a multi-factorial disease with an inflammatory background that occurs in both soft and hard tissues surrounding implants. In recent years, the understanding of the cellular, molecular and genetic background of peri-implantitis has broadened. This study aims to summarize the currently available articles on the subject and highlight the most recent advances over the last 20 years. (2) Methods: For this study, the Embase and PubMed libraries were searched using the keywords: ("peri-implantitis" AND "cytokine" OR "genetics" OR "cellular") and ("peri-implantitis" AND "cytokine" OR "genetics" OR "cellular" AND "risk factors"). The search revealed a total of 3013 articles (992 from PubMed, 2021 from Embase). Following screening of the titles and abstracts and full-text reads, 55 articles were included. (3) Results: In peri-implantitis IL-6, IL-1β, TNF-α, MMP-8 and their genetic variations appear to be the most important cytokines in relation to not only pathogenesis, but also their potential diagnostic capabilities. Epithelial and inflammatory cells, along with those of the bone lineage, are prime cellular elements found in peri-implantitis. (4) Conclusions: A wide array of cells stand behind peri-implantitis, as well as cytokines and their genetic variations that take part in the process. However, the growing interest in this topic has led to the introduction of specific new diagnostic tools to enable a better understanding of patients' responses to treatment and, in turn, to even enable prediction of the risk of developing peri-implant disease.

Association between implant surface roughness, smoking habits and implant site location on the occurrence of peri-implantitis: a pooled retrospective cohort study

Background: Peri-implantitis is a multi-factorial disease that affects dental implants surrounding tissues. The identification of risk factors and risk indicators could contribute to explain the heterogeneity of the disease onset and progression. The aim of the present study is to investigate the influence of implant surface roughness and other initial conditions on the future development of peri-implantitis disease by means of a pooled individual data.

Antimicrobial Photodynamic Therapy (aPDT) as a Disinfection and Biomodulation Approach in Implant Dentistry.

This article is a highlight of the paper by Choe etal. in this issue ofPhotochemistry and Photobiology. In that review paper, the disinfection and biomodulation outcomes promoted by antimicrobial photodynamic therapy (aPDT) on peri-implantitis infection were stated and discussed. The killing of the oral pathogens by aPDT is based on the generation of reactive oxygen species (ROS). Besides that, biomodulation can also be provided by aPDT and improve the healing and modulate the inflammatory process. Although aPDT has shown positive effects on the treatment of peri-implantitis disease mainly as a complimentary technique, the authors suggested that more and standardize clinical studies are needed to support the clinical application of aPDT for that purpose. Also, the standardization of parameters related to the light source and photosensitizers is required. In addition, nano-based materials may improve aPDT performance against oral biofilms and could increase the hopes of overcoming dental implant failures.

Rough Dental Implant Surfaces and Peri-Implantitis: Role of Phase-Contrast Microscopy, Laser Protocols, and Modified Home Oral Hygiene in Maintenance. A 10-Year Retrospective Study

The aim of this study was to evaluate two different kinds of rough implant surface and to assess their tendency to peri-implantitis disease, with a follow-up of more than 10 years. Data were obtained from a cluster of 500 implants with Ti-Unite surface and 1000 implants with Ossean surface, with a minimum follow-up of 10 years. Implants had been inserted both in pristine bone and regenerated bone. We registered incidence of peri-implantitis and other causes of implant loss. All patients agreed with the following maintenance protocol: sonic brush with vertical movement (Broxo), interdental brushes, and oral irrigators (Broxo) at least two times every day. For all patients with implants, we evaluated subgingival plaque samples by phase-contrast microscopy every 4 months for a period of more than 10-years. Ti-Unite surface implants underwent peri-implantitis in 1.6% of the total number of implants inserted and Ossean surface implants showed peri-implantitis in 1.5% of the total number of implants. The total percentage of implant lost was 4% for Ti-Unite surfaces and 3.6% for Ossean surfaces. Strict control of implants leads to low percentage of peri-implantitis even for rough surfaces dental implants.

Etiologia e tratamento das doenças peri-implantares

Objetivo: O propósito do presente estudo foi discutir, através de uma revista da literatura, a etiologia, e os protocolos de tratamento mais indicados para peri-implantite. Métodos: a pesquisa foi realizada nas seguintes base de dados: Scielo e Medline via Pubmed. Como estratégia de busca, foram utilizados os seguintes descritores “Decs”: ‘implantes dentários’, ‘Peri-implantite’, ‘Periodontite’ e ‘Osseointegração’ no Scielo, bem como os meshes no Pubmed: ‘dental implants’, ‘peri-implantitis’ e ‘osseointegration’. Por fim, 24 estudos relacionados ao assunto foram selecionados. Resultados: Os implantes osseointegrados vêm sendo cada vez mais utilizados nas reabilitações orais. Apesar da alta taxa de sucesso e longevidade desse tratamento, alguns casos podem ser acometidos por doenças peri-implantares. A peri-implantite é uma doença infecciosa bacteriana que afeta tecidos moles e duros em torno do implante, podendo ocasionar a perda da osseointegração. Vários fatores são apontados como causadores da perda óssea peri-implantar. Por ser de caráter multifatorial, pode exacerbar a perda de altura óssea, dificultar a cicatrização após cirurgia, e causar a falha do implante. Considerações finais: Os métodos de tratamentos das doenças peri-implantares são os mais diversos possíveis, incluindo modalidades cirúrgicas e não cirúrgicas, além de terapias fotodinâmicas e regenerativas. Por ser uma doença relativamente nova, ainda não há consenso entre os profissionais sobre qual o melhor protocolo de tratamento. Faz-se necessária a realização de novos estudos que possam viabilizar a elaboração de protocolos clínicos para controle e tratamento da peri-implantite.

Contribution of fungi and viruses towards the etiopathogenesis peri-implantitis: A literature review of currently available evidence

• The aim was to review the contribution of fungi and viruses towards the progression of peri-implant diseases. • Indexed databases were searched using various keywords • Candida species particularly Candida albicans is associated with the etiology of peri-implantitis • Herpes- and Epstein-Barr virus exacerbate peri-implantitis diseases The aim of the present literature review was to evaluate the contribution of fungi and viruses towards the etiopathogenesis of peri-implant diseases. The focused question addressed was “Can fungi and viruses contribute towards the etiopathogenesis of peri-implant diseases?”. The databases, which were used for the literature search comprised of ISI Web of knowledge, OVID, PubMed/ Medline, EMBASE, Google-Scholar and Scopus. These databases were searched up to March 2020. Diverse groupings of the following key-indexing terms were done to identify the relevant studies: “ Candida ”, “fungi”, “yeast”, “crestal bone loss”, “microbe”, “peri-implant diseases”, “dental implant”, “etiopathogenesis”, “inflammation”, “peri-implant mucositis”, “peri-implantitis”, and “virus”. The pattern of the present literature review was customized to summarize the pertinent information. Five studies showed that in the presence of Porphyromonas gingivalis , herpes- and Epstein-Barr virus exacerbate peri-implantitis diseases. Seven studies associated oral yeasts (predominantly Candida species) with the etiology of peri-implantitis. Results from these studies showed that in the presence of periodonto-pathogenic bacteria, growth of Candida albicans is exacerbated that also may increase soft tissue inflammation and crestal bone loss around dental implants. Additional studies are needed to confirm the role of fungi and viruses towards the etiopathogenesis of peri-implant diseases. In the presence of periodontopathogenic bacteria, virulence of oral fungi and viruses seems to be increased. This in turn may worsen peri-implant inflammation in susceptible patients. However, a justification for this requires further studies.

Development of a Novel Medical Device for Mucositis and Peri-Implantitis Treatment.

In spite of all the developments in dental implantology techniques, peri-implant diseases are frequent (prevalence up to 80% and 56% of subjects for mucositis and peri-implantitis, respectively) and there is an urgency for an effective treatment strategy. This paper presents an innovative electromedical device for the electromagnetic treatment of mucositis and peri-implantitis diseases. This device is also equipped with a measurement part for bioimpedance, which reflects the health conditions of a tissue, thus allowing clinicians to objectively detect impaired areas and to monitor the severity of the disease, evaluate the treatment efficacy, and adjust it accordingly. The design of the device was realized considering literature data, clinical evidence, numerical simulation results, and electromagnetic compatibility (EMC) pre-compliance tests, involving both clinicians and engineers, to better understand all the needs and translate them into design requirements. The reported system is being tested in more than 50 dental offices since 2019, providing efficient treatments for mucositis and peri-implantitis, with success rates of approximately 98% and 80%, respectively.

RETRACTED ARTICLE: Structural Characterization of a Mn(II)-Based Coordination Polymer and Application of Its Nanoparticles for the Protective Effect in Peri-Implantitis Therapy by Enhancing the Immune Cell Response

A novel metal-organic framework, namely, [Mn(tib)2(HCOO)2]-2H2O (1, tib = 1,3,5-tri(1H-imidazol-1-yl)benzene) is prepared under hydrothermal conditions and characterized by the elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. A green-hand grinding technique is implemented to reduce the particle size of 1 to generate nanoscale particles (denoted as nano-1 hereafter). The effect of treatment of peri-implantitis diseases with nano-1 is evaluated.

Structural characterization of a Mn(II)-based coordination polymer and application of its nanoparticles for the protective effect in peri-implantitis therapy by enhancing the immune cell response

A novel metal-organic framework, namely, [Mn(tib)2(HCOO)2]×2H2O (1, tib = 1,3,5-tri(1H-imidazol-1-yl)benzene) is prepared under hydrothermal conditions and characterized by the elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. A green-hand grin­ding technique is implemented to reduce the particle size of 1 to generate nanoscale particles (denoted as nano-1 hereafter). The effect of treatment of peri-implantitis diseases with nano-1 is evaluated.

Development of a peri-implantitis model in the rat.

The aim of the present study was to establish a rodent peri-implantitis model induced by a mixed bacterial infection characterized by bone loss and semi-quantitative graduation of peri-implant inflammation in histological sections. Two titanium implants were implanted in Sprague-Dawley rats, bilaterally in each maxilla. After 3weeks healing, the rats were randomized into three groups according to different treatments over the next 3months: Antibiotic-Group with oral lavage of antibiotics; Bacteria-Group with oral lavage of Streptococcus oralis and Aggregatibacter actinomycetemcomitans; and Untreated Group with standard housing and no additional treatment. Maxillae were dissected to perform microscopic and histological analysis of bone height and peri-implant tissues. The bone level, measured at one implant site per animal, in the Bacteria-Group (2.60±0.39mm) was significantly reduced compared to the Antibiotic-Group (2.29±0.32mm) after 3months. The differences of bone height in the Bacteria-Group and the Untreated Group (2.46±0.27mm) did not reach statistical significance. The inflammatory response with respect to the number of inflammatory cells and fibrous tissue compartments of the peri-implant tissues in the Bacteria-Group was significantly increased compared with the Antibiotic-Group (p<.05). S. oralis and A. actinomycetemcomitans DNAs were detected in the Bacteria-Group. This rat model of peri-implantitis used oral bacterial lavage for the induction of an inflammatory host response and bone loss. Additional bacterial treatment enhances the peri-implant phenotype, so that significant differences to a reduced bacterial load similar to the human peri-implantitis disease can be identified.

Early intervention of peri-implantitis and periodontitis using a mouse model.

Peri-implantitis is an inflammatory response to bacterial biofilm resulting in bone loss and can ultimately lead to implant failure. Because of the lack of predictable treatments available, a thorough understanding of peri-implantitis's pathogenesis is essential. The objective of this study is to evaluate and compare the response of acute induced peri-implantitis and periodontitis lesions after insult removal. Implants were placed in one-month-old C57BL/6J male mice eight weeks post extraction of their left maxillary molars. Once osseointegrated, ligatures were placed around the implants and contralateral second molars of the experimental groups. Controls did not receive ligatures. After one week, half of the ligatures were removed, creating the ligature-retained and ligature-removed groups. Mice were sacrificed at two time points, 5 and 14 days, from ligature removal. The specimens were analyzed via micro-computed tomography and histology. By 5 and 14 days after ligature removal, the periodontitis group experienced significant bone gain, whereas the peri-implantitis group did not. Histologically, all implant groups exhibited higher levels of cellular infiltrate than any of the tooth groups. Osteoclast numbers increased in peri-implantitis and periodontitis ligature-retained groups and decreased following insult removal. Collagen was overall more disorganized in peri-implantitis than periodontitis for all groups. Peri-implantitis experimental groups revealed greater matrix metalloproteinase-8 and NF-kB levels than periodontitis. Implants respond slower and less favorably to insult removal than teeth. Future research is needed to characterize detailed peri-implantitis disease pathophysiology.

Evaluation of cell activation promoted by tantalum and tantalum oxide coatings deposited by reactive DC magnetron sputtering

Previous studies have shown both Ta and TaO to be bioactive, rapidly forming a strongly-bonded surface-adherent layer of bone-like hydroxyapatite (HAp) when immersed in simulated body fluid (SBF). Consequently, Ta and TaO coatings are promising for the surface-modification of Ti or stainless steel endodontic endosseous implants, being conducive to a reduction in the risk of developing post-operatory infection and/or peri-implantitis disease. That said, few studies have investigated the effect of Ta or TaO coatings on such phenomena as cell activation, adhesion, and proliferation.To that effect, Ta, and TaO films were deposited onto type 316L stainless steel (SS 316L) substrates by reactive DC magnetron sputtering, after which their biological response was evaluated following co-incubation with the murine macrophage-like cell line RAW 264.7. Cell morphology after adhesion was observed by SEM, whereas cell viability and proliferation were evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. Lastly, inflammatory response was assessed by quantification of the cytokines interleukin-6 (IL-6) and interleukin-10 (IL-10).In terms of phase composition, Ta showed a mixture of the α-Ta and β-Ta phases, whereas TaO showed a nanocrystalline structure. Moreover, a decrease in average roughness (Ra) from 21nm to 7nm was observed between Ta and TaO, accompanied by a decrease in water contact angle (θW) from 106° to 83°.In vitro studies showed that cells exhibited significantly better adhesion to Ta, in comparison with both TaO and SS 316L. Furthermore, both Ta and TaO were shown to be non-cytotoxic, with Ta outperforming TaO in terms of relative cell viability, both at 24h and 48h. Lastly, both Ta and TaO showed vastly inferior IL-6 and IL-10 levels to those obtained for cells treated with bacterial lipopolysaccharides (LPS)—prompting the conclusion that the coatings do not in any way induce an inflammatory response from macrophage cells.

Bioactivity response of Ta1-xOx coatings deposited by reactive DC magnetron sputtering.

The use of dental implants is sometimes accompanied by failure due to periimplantitis disease and subsequently poor esthetics when soft-hard tissue margin recedes. As a consequence, further research is needed for developing new bioactive surfaces able to enhance the osseous growth. Tantalum (Ta) is a promising material for dental implants since, comparing with titanium (Ti), it is bioactive and has an interesting chemistry which promotes the osseointegration. Another promising approach for implantology is the development of implants with oxidized surfaces since bone progenitor cells interact with the oxide layer forming a diffusion zone due to its ability to bind with calcium which promotes a stronger bond. In the present report Ta-based coatings were deposited by reactive DC magnetron sputtering onto Ti CP substrates in an Ar+O2 atmosphere. In order to assess the osteoconductive response of the studied materials, contact angle and in vitro tests of the samples immersed in Simulated Body Fluid (SBF) were performed. Structural results showed that oxide phases where achieved with larger amounts of oxygen (70 at.% O). More compact and smooth coatings were deposited by increasing the oxygen content. The as-deposited Ta coating presented the most hydrophobic character (100°); with increasing oxygen amount contact angles progressively diminished, down to the lowest measured value, 63°. The higher wettability is also accompanied by an increase on the surface energy. Bioactivity tests demonstrated that highest O-content coating, in good agreement with wettability and surface energy values, showed an increased affinity for apatite adhesion, with higher Ca/P ratio formation, when compared to the bare Ti substrates.

Health, Maintenance, and Recovery of Soft Tissues around Implants.

The health of peri-implant soft tissues is one of the most important aspects of osseointegration necessary for the long-term survival of dental implants. To review the process of soft tissue healing around osseointegrated implants and discuss the maintenance requirements as well as the possible short-comings of peri-implant soft tissue integration. Literature search on the process involved in osseointegration, soft tissue healing and currently available treatment modalities was performed and a brief description of each process was provided. The peri-implant interface has been shown to be less effective than natural teeth in resisting bacterial invasion because gingival fiber alignment and reduced vascular supply make it more vulnerable to subsequent peri-implant disease and future bone loss around implants. And we summarized common procedures which have been shown to be effective in preventing peri-implantitis disease progression as well as clinical techniques utilized to regenerate soft tissues with bone loss in advanced cases of peri-implantitis. Due to the difference between peri-implant interface and natural teeth, clinicians and patients should pay more attention in the maintenance and recovery of soft tissues around implants.

Peri‐Implantitis versus Periodontitis: Functional Differences Indicated by Transcriptome Profiling

Periodontitis and Periimplantitis are oftentimes discussed as one entity, which is reflected by therapeutical as well as by scientific approaches. It is unclear, to which extent the similarity of the clinical characteristics is attributed to similarities in the underlying disease mechanisms. The main objective of the study is to display if or how different periimplantitis and periodontitis are on the mRNA level, representing a high-resolution map of disease-associated events. Aiming to describe the pathophysiological mechanisms in vivo, primary gingival tissue from 7 periimplantitis patients, 7 periodontitis patients and 8 healthy controls was employed in order to generate genome wide transcriptome profiles. On the basis of quantitative transcriptome analysis, we could show that periimplantitis and periodontitis exhibit significantly different mRNA signatures. Additionally we present a disease associated mRNA profile, which displays potential periimplantitis disease mechanisms. A gene ontology analysis revealed various pathways, supporting the hypothesis of periimplantitis being a complex inflammatory disorder with a unique pathophysiology. While in periimplantitis tissue the regulation of transcripts related to innate immune responses and defense responses were dominating, in periodontitis tissues bacterial response systems prevailed. Taken together, our results suggest considering periimplantitis and periodontitis as disease entities with shared as well as with distinct features, which should be reflected on the therapeutical as well as on the scientific level.