Real Appearance of Dendritic Cell on Failed Implant Fixture

Role of immune dysregulation in peri-implantitis

Peri-implantitis, a complex condition that can lead to dental implant failure, is characterized by inflammatory destruction resulting from immune dysregulation. Oral microbial dysbiosis and foreign body stimulation are the main factors contributing to such dysregulation, impairing immune cell function and triggering an inflammatory response. Immune dysregulation plays a critical role in the pathophysiology of peri-implantitis, impacting the balance of T cell subsets, the production of inflammatory factors, and immune-related molecular signaling pathways. Understanding the relationship between immune dysregulation and peri-implantitis is crucial for developing targeted strategies for clinical diagnosis and individualized treatment planning. This review explores the similarities and differences in the immune microenvironment of oral bacterial infections and foreign body rejection, analyzes the relevant molecular signaling pathways, and identifies new key targets for developing innovative immunotherapeutic drugs and effective and personalized treatment modalities for peri-implantitis. Additionally, it addresses the challenges and potential directions for translating immunotherapy into clinical practice for peri-implantitis, offering insights that bridge the gaps in current literature and pave the way for future research.

Deciphering peri-implantitis: Unraveling signature genes and immune cell associations through bioinformatics and machine learning

Early diagnosis of peri-implantitis (PI) is crucial to understand its pathological progression and prevention. This study is committed to investigating the signature genes, relevant signaling pathways and their associations with immune cells in PI. We analyzed differentially expressed genes (DEGs) from a PI dataset in the gene expression omnibus database. Functional enrichment analysis was conducted for these DEGs. Weighted Gene Co-expression Network Analysis was used to identify specific modules. Least absolute shrinkage and selection operator and support vector machine recursive feature elimination were ultimately applied to identify the signature genes. These genes were subsequently validated in an external dataset. And the immune cells infiltration was classified using CIBERSORT. A total of 180 DEGs were screened from GSE33774. Weighted Gene Co-expression Network Analysis revealed a significant association between the MEturquoise module and PI (cor = 0.6, P < .0001). Least absolute shrinkage and selection operator and support vector machine recursive feature elimination algorithms were applied to select the signature genes, containing myeloid-epithelial-reproductive tyrosine kinase, microfibrillar-associated protein 5, membrane-spanning 4A 4A, tribbles homolog 1. In the validation on the external dataset GSE106090, all these genes achieved area under curve values exceeding 0.95. GSEA analysis showed that these genes were correlated with the NOD-like receptor signaling pathway, metabolism of xenobiotics by cytochrome P450, and arachidonic acid metabolism. CIBERSORT revealed elevated levels of macrophage M2 and activated mast cells in PI. This study provides novel insights into understanding the molecular mechanisms of PI and contributes to advancements in its early diagnosis and prevention.

Electron microscopic analysis of necrotic bone and failed implant surface in a patient with medication-related osteonecrosis of the jaw

BACKGROUND

Bisphosphonates (BP), a commonly used medication for various bone diseases, have been known to have severe complications such as bisphosphonate-related osteonecrosis of the jaw (BRONJ). Failure of dental implants has also been found in patients with medication-related osteonecrosis of the jaw (MRONJ). In this study, we analyzed the necrotic bone tissues and the surface of the failed implants removed from the jaw in patients treated with BPs and antiresorptive agents.

RESULTS

Chronic inflammatory cells with collagen and fibrous tissues and bone sequestrum were shown at 5.0 × , 10.0 × , 20.0 × , and 40.0 × magnified histologic sections in the bone and fibrotic scar tissues removed from patients with MRONJ due to osteonecrosis. Hardened bone tissues with microcracked bony resorbed lacunae were observed in SEM. Unlike the previously published comparative data where immune cells, such as dendritic cells, were found in the failed implant surface, these immune cells were not identified in the BRONJ-related peri-implantitis tissues through the TEM investigations. Furthermore, EDS revealed that in addition to the main titanium element, gold, carbon, oxygen, calcium, phosphorus, silicon, and sulfur elements were found.

CONCLUSION

Hardened bone tissues with microcracked bony resorbed lacunae were observed in the SEM findings, which were considered as the main characteristic of the osteonecrosis of the jaw. Immune cells, such as dendritic cells were not identified in the TEM. EDS showed that in addition to the main titanium element, gold, carbon, oxygen, calcium, phosphorus, and silicon elements were found. Furthermore, it was revealed that sulfur was found, which was considered to be one of the complicated causes of implant failure in patients with BRONJ.

Evaluation of the Quality of Peri-implantitis Videos on YouTube

Although many studies have evaluated the quality of YouTube videos related to dentistry, just one study has evaluated the quality of YouTube videos related to peri-implantitis. The aim of the cross-sectional study was to evaluate the quality of peri-implantitis-related YouTube videos. Two periodontists evaluated 47 videos that met the inclusion criteria, such as the country of upload, source of videos, number of views, likes and dislikes, viewing rate, interaction index, number of days since upload, duration of the video, usefulness score, global quality scale score, and comments. Peri-implantitis was evaluated using a 7-question system of the videos, 44.7% and 55.3% were uploaded by commercial companies and health care professionals, respectively. Although the usefulness score of the videos uploaded by health care professionals was statistically significantly higher ( P =0.022), the number of views, numbers of likes and dislikes were similar between the groups ( P >0.050). Although the usefulness score and global quality scale score of the perfect videos were statistically different between the groups ( P <0.001; P <0.001, respectively), the number of views, numbers of likes, and dislikes were similar. A strong positive correlation was found between the number of views and the number of likes ( P ˂0.001). A strong negative correlation was found between the interaction index and the number of days since upload ( P ˂0.001). As a result, YouTube videos on peri-implantitis were limited in number and had poor quality. Thus, videos of perfect quality should be uploaded.

Antibacterial Adhesion Strategy for Dental Titanium Implant Surfaces: From Mechanisms to Application

Dental implants are widely used to restore missing teeth because of their stability and comfort characteristics. Peri-implant infection may lead to implant failure and other profound consequences. It is believed that peri-implantitis is closely related to the formation of biofilms, which are difficult to remove once formed. Therefore, endowing titanium implants with anti-adhesion properties is an effective method to prevent peri-implant infection. Moreover, anti-adhesion strategies for titanium implant surfaces are critical steps for resisting bacterial adherence. This article reviews the process of bacterial adhesion, the material properties that may affect the process, and the anti-adhesion strategies that have been proven effective and promising in practice. This article intends to be a reference for further improvement of the antibacterial adhesion strategy in clinical application and for related research on titanium implant surfaces.

Analysis of acute sinusitis-related early failed implant surface: a combined histological, electron microscopy, and X-ray spectroscopy approach

BACKGROUND

Even though dental implants are a reliable choice for dental rehabilitation, implant failures due to various etiologies have been reported. Early implant failures account for 2 to 6% of installed implants and are reported to have a higher rate than late failures, regardless of loading time. We herein report three cases of acute sinusitis and early implant failure with implants that failed within 1 month after installation. The aim of this study was to evaluate the surface properties of early failed implants and peri-implant tissue to determine the early osseointegration pattern in acute sinusitis-related failed implants as well as the possible role of surface contamination in the failure of osseointegration.

RESULTS

A combined histological, electron microscopy, and X-ray spectroscopy approach was used to characterize the surface of non-osseointegrated titanium implants and the surrounding biological tissues. Morphologic scanning electron microscopy revealed a heterogeneous surface and irregular osseointegration. The implant surface was covered mostly by carbon- and oxygen-rich organic matter. Energy-dispersive X-ray spectroscopy surface analysis of three implants showed the incorporation of some contaminants in both the upper and apical regions. Carbon, nitrogen, sodium, silicon, chlorine, sulfur, gold, and zirconium were detected on the surface of one or more failed implants. Fibrosis, lymphocytic, and macrophage infiltrates and a high activation of osteoclasts surrounding the bone graft particles were detected in the surrounding tissues.

CONCLUSIONS

The etiology and mechanism of early implant failure, especially in sinus-related cases, as well as the proper management interventions to minimize the rate of early implant failures, are of great concern. No matter how confident and accurate the surgeon's operation, there may be unknown errors in the whole procedure that no one knows about. Rather than errors related to the implant surface, it is expected that there were invisible problems during the evaluation of the patient's own unique sinus mucosal inflammation or the operator's own procedure. Furthermore, well-designed researches are necessary to reveal the effect of material-related factors on acute sinus complication and early implant failure.

Energy-Dispersive X-Ray Spectroscopic Analysis of an Extraorally Installed Implant in a Silicone Facial Prosthesis Patient

ABSTRACT

Titanium implants are considered to be highly biocompatible relative to other metals, and the use of this metal is increasing more and more. However, studies on its possible toxic effects are rare. A patient who had a large midface defect was treated with an implant-supported magnet-retained silicone prosthesis; however, the extraoral implant failed. Scanning electron microscopy and energy dispersive X-ray spectroscopy was used to analyze the surface characteristics and the chemical compositions of the failed implant fixture and attached bone tissue. The contamination of the implant and bone tissue with aluminum (Al), iron (Fe), and mercury (Hg) potentially had an influence on the integration of bone tissue and the health of peri-implant tissue. The exposure of the facial prosthesis and its implant to the external environment may have caused the contamination. Careful clinical examination during the follow-up period and adequate hygiene is essential for the long-term success of implant-supported prostheses.