Topological insight of immune-vascular distribution in peri-implantitis lesions.

OBJECTIVE: To characterize the distribution of macrophages, neutrophils, NK cells, and blood vessels in peri-implantitis compared to healthy aged gingiva samples. MATERIALS AND METHODS: This observational study included eight gingival samples from peri-implantitis and eight from periodontally healthy individuals. By immunofluorescence were identified neutrophils, NK cells, macrophages, and their pro-inflammatory or pro-healing phenotypes, and blood vessels. Two ROIs were designated as zone 1, connective tissue closest to the epithelium and zone 2, connective tissue over 200 microns from the rete ridges. Immune cells and vascular structures were quantified and characterized according to their distribution in both zones. RESULTS: Two peri-implantitis zones were characterized by unique macrophage phenotypes and blood vessel architecture. Blood vessels were larger in zone 2 in peri-implantitis. A greater number of NK cells and macrophages were found in peri-implantitis compared to healthy aged samples. A higher presence of pro-inflammatory macrophages was found in zone 1 compared to zone 2. A similar proportion of pro-inflammatory and pro-healing macrophages were found in zone 2. CONCLUSION: A specific distribution for pro-inflammatory macrophages and vascular architecture is observed in peri-implantitis. TNF-α colocalizes with macrophages in the connective tissue near rete ridges. NK cells are more abundant in peri-implantitis than in healthy samples.

Single-cell analysis reveals a unique microenvironment in peri-implantitis.

AIM: This study aimed to reveal the unique microenvironment of peri-implantitis through single-cell analysis. MATERIALS AND METHODS: Herein, we performed single-cell RNA sequencing (scRNA-seq) of biopsies from patients with peri-implantitis (PI) and compared the results with healthy individuals (H) and patients with periodontitis (PD). RESULTS: Decreased numbers of stromal cells and increased immune cells were found in the PI group, which implies a severe inflammatory infiltration. The fibroblasts were found to be heterogeneous and the specific pro-inflammatory CXCL13+ sub-cluster was more represented in the PI group, in contrast to the PD and H groups. Furthermore, more neutrophil infiltration was detected in the PI group than in the PD group, and cell-cell communication and ligand-receptor pairs revealed most neutrophils were recruited by CXCL13+ fibroblasts through CXCL8/CXCL6-CXCR2/CXCR1. Notably, our study demonstrated that the unique microenvironment of the PI group promoted the differentiation of monocyte/macrophage lineage cells into osteoclasts, which might explain the faster and more severe bone resorption in the progression of PI than PD. CONCLUSIONS: Collectively, this study suggests a unique immune microenvironment of PI, which may explain the differences between PI and PD in the clinic. These outcomes will aid in finding new specific and effective treatments for PI.

Echo-intensity characterization at implant sites and novel diagnostic ultrasonographic markers for peri-implantitis.

AIM: To apply high-frequency ultrasound (HFUS) echo intensity for characterizing peri-implant tissues at healthy and diseased sites and to investigate the possible ultrasonographic markers of health versus disease. MATERIALS AND METHODS: Sixty patients presenting 60 implants diagnosed as healthy (N = 30) and peri-implantitis (N = 30) were assessed with HFUS. HFUS scans were imported into a software where first-order greyscale outcomes [i.e., mean echo intensity (EI)] and second-order greyscale outcomes were assessed. Other ultrasonographic outcomes of interest involved the vertical extension of the hypoechoic supracrestal area (HSA), soft-tissue area (STA) and buccal bone dehiscence (BBD), among others. RESULTS: HFUS EI mean values obtained from peri-implant soft tissue at healthy and diseased sites were 122.9 ± 19.7 and 107.9 ± 24.7 grey levels (GL); p = .02, respectively. All the diseased sites showed the appearance of an HSA that was not present in healthy implants (area under the curve = 1). The proportion of HSA/STA was 37.9% ± 14.8%. Regression analysis showed that EI of the peri-implant soft tissue was significantly different between healthy and peri-implantitis sites (odds ratio 0.97 [95% confidence interval: 0.94-0.99], p = .019). CONCLUSIONS: HFUS EI characterization of peri-implant tissues shows a significant difference between healthy and diseased sites. HFUS EI and the presence/absence of an HSA may be valid diagnostic ultrasonographic markers to discriminate peri-implant health status.

Impact of the Habit of Alcohol Consumption on the Success of the Implants: A Retrospective Study.

Introduction: A recent study has demonstrated that social factors have an impact on the condition of dental implants. The present investigation investigated how varied alcohol intake quantities might alter the condition of dental implants and related peri-implant inflammation. Materials and Methods: This retrospective research was piloted in a tertiary care center, and implants inserted between 2010 and 2022 were evaluated through a retrospective cohort analysis. Within 3 months following implant implantation, information on alcohol intake was gathered from the health maintenance records and employed as the predictor variable. The implant results as well as peri-implantitis were examined at follow-up visits. Using the logistic regression model, the Wald test analysis analyzed the statistical consequences of each parameter. The findings were translated using an odds ratio that was determined with a 95% confidence level. The data were generated and analyzed using descriptive statistics, with statistical significance defined as P < 0.05. Results: At the time of implant placement, the enrolled patients were 59 ± 11.3 years old on average. The median time before peri-implantitis occurred was 31.3 ± 22.2 months. Within the first 2 years following implant implantation, the majority of people experienced peri-implantitis. The incidence of peri-implantitis was the lowest among light and moderate alcoholics (11.5%) and the highest among heavy alcoholics (46.2%). Moderate alcohol use was associated with a 79.1% decrease in peri-implantitis when compared to not drinking (P = 0.0365), whereas light alcohol consumption was connected to a 51.3% decrease (P = 0.026). The incidence of peri-implantitis among heavy drinkers was significantly significant (P = 0.0001). Conclusion: According to the findings of the current retrospective cohort analysis, drinking alcohol at mild-to-moderate levels is connected to a reduction in the incidence rate of peri-implantitis compared to heavy drinkers. In contrast, high alcohol consumption was found to be associated with an increase in the prevalence of peri-implantitis among the participants who had dental implants.

Investigating the Long-Term Success and Complication Rates of Zirconia Dental Implants: A Prospective Clinical Study.

This study addresses the durability and complications of zirconia dental implants through a prospective clinical investigation. Zirconia implants are increasingly utilized in dental implantation, and a comprehensive understanding of their long-term performance is essential. Background: Zirconia dental implants have gained attention due to their biocompatibility and aesthetics. However, research on their extended success and complication rates is limited. Materials and Methods: A prospective clinical study involved the placement of 30 zirconia dental implants in patients requiring tooth replacement. The implants were followed up for five years. Success was defined as the implant remaining stable and functional. Complications, including peri-implant mucositis and peri-implantitis, were monitored. Statistical analysis included descriptive statistics, Chi-square test, and P-values were set at P < 0.05. Results: The long-term success rate of zirconia dental implants was found to be 93.3%. Among the 30 implants, only 2 exhibited failure. The most common complication was peri-implant mucositis, occurring in 16.7% of implants. Notably, the incidence of peri-implantitis was limited, observed in 6.7% of implants. Statistical analysis showed significant associations between implant failure and smoking (P = 0.021). Conclusion: Zirconia dental implants demonstrated a high long-term success rate of 93.3% over five years. Peri-implant mucositis was the predominant complication, with a relatively low occurrence of peri-implantitis. The findings underscore the potential of zirconia implants for reliable dental implantation. Addressing modifiable risk factors, such as smoking, could further enhance implant success. Continued research is recommended to validate and expand upon these outcomes.

Effect of bioceramic powder abrasion on different implant surfaces.

PURPOSE: Bioceramic coatings have been shown to promote bone repair, which aids in the early integration of implants. This study aimed to evaluate the influence of air abrasion with a bioceramic abrasive on the surface characteristics of different implant materials and surfaces. The dissolution of the applied treatment from the surfaces over 3 weeks was also assessed. MATERIALS AND METHODS: Discs of three alloys used for dental implants were studied and compared: two types of commercially pure titanium (CpTi)/ (CpTi SLActive) and titanium-zirconia (TiZr). The tested surfaces were: CpTi control (CpC), sandblasted (SB), sandblasted and acid-etched (SBE), and CpTi SLActive®, (TiZr) Roxolid®. Three discs from each group underwent air abrasion with apatite bioceramic powders, 95% hydroxyapatite (HA)/5% calcium oxide (CaO), and 90% hydroxyapatite (HA)/10% calcium oxide (CaO). The treated discs were surface characterized by optical profilometry to obtain surface roughness, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) to compare element weight percentages of titanium, calcium, and phosphate. Dissolution was assessed using inductively coupled plasma optic emission spectrometry (ICP-OES). RESULTS: Bioceramic powders were deposited on all tested surfaces leading to changes in surface characteristics. The only statistically significant differences between the material groups for surface roughness were found with 95% HA/5% CaO powder in the Sp and Rp parameters (p = 0.03 and 0.04, respectively). There were no significant differences in the Ca and P wt% between all groups and powders 95% HA/5% CaO and 90% HA/10% CaO (p = 0.14, 0.18, and p = 0.15, 0.12, respectively). A non-uniform dispersion of the treatment on the surface layer was visible on all treated surfaces. The bioceramic powder continued to dissolute from the tested surfaces for 3 weeks. CONCLUSION: Bioceramic abrasion modifies implant surface characteristics, although the change in surface characteristics resulting from such treatment was not influenced by the implant material or surface treatment. Air abrasion with hydroxyapatite and calcium oxide bioceramics leaves powder deposits on the treated implant surfaces that could potentially influence the healing of implants affected by peri-implantitis.

Sustained Release of Salicylic Acid for Halting Peri-Implantitis Progression in Healthy and Hyperglycemic Systemic Conditions: A Gottingen Minipig Model.

To develop a peri-implantitis model in a Gottingen minipig and evaluate the effect of local application of salicylic acid poly(anhydride-ester) (SAPAE) on peri-implantitis progression in healthy, metabolic syndrome (MS), and type-2 diabetes mellitus (T2DM) subjects. Eighteen animals were allocated to three groups: (i) control, (ii) MS (diet for obesity induction), and (iii) T2DM (diet plus streptozotocin for T2DM induction). Maxillary and mandible premolars and first molar were extracted. After 3 months of healing, four implants per side were placed in both jaws of each animal. After 2 months, peri-implantitis was induced by plaque formation using silk ligatures. SAPAE polymer was mixed with mineral oil (3.75 mg/µL) and topically applied biweekly for up to 60 days to halt peri-implantitis progression. Periodontal probing was used to assess pocket depth over time, followed by histomorphologic analysis of harvested samples. The adopted protocol resulted in the onset of peri-implantitis, with healthy minipigs taking twice as long to reach the same level of probing depth relative to MS and T2DM subjects (∼3.0 mm), irrespective of jaw. In a qualitative analysis, SAPAE therapy revealed decreased levels of inflammation in the normoglycemic, MS, and T2DM groups. SAPAE application around implants significantly reduced the progression of peri-implantitis after ∼15 days of therapy, with ∼30% lower probing depth for all systemic conditions and similar rates of probing depth increase per week between the control and SAPAE groups. MS and T2DM conditions presented a faster progression of the peri-implant pocket depth. SAPAE treatment reduced peri-implantitis progression in healthy, MS, and T2DM groups.

Malignancy around implants in patients with a history of a potentially malignant or malignant lesion: a systematic review.

The majority of problematic conditions resulting from dental implant treatment are inflammatory in character, but certain isolated occurrences of primary oral squamous cell carcinoma (OSCC) have been discovered in the area of implants. The goal of this study was to examine whether there is a link between dental implants and the development of OSCC in patients who have a history of a potentially malignant lesion (PML) or malignancy. Using the keywords "carcinoma" AND "dental implants," a search was conducted in the MEDLINE (PubMed), National Center for Biotechnology Information, and Google Scholar databases for case reports and case series in which OSCC was discovered as a primary cancer in the region of dental implants. An initial search identified 260 articles, 247 of which were excluded based on study inclusion or exclusion criteria, leaving 13 articles chosen for inclusion and a total of 30 patients who developed primary oral cancer surrounding osseointegrated titanium-based dental implants. In the studies included in the present review, 22 (73%) of 30 patients with peri-implant cancer had a history of PML or carcinoma. There is no statistical evidence of a direct association between dental implants and OSCC in patients with a history of a PML or malignant lesion. There have been some case reports of OSCC in the region of dental implants in patients with a history of a PML or malignant lesion, but further studies are needed to prove a definitive relationship.

Time management in multistep periodontal and implant treatments: a practical guide.

In addition to the proper selection of techniques, appropriate treatment sequencing and prioritization are prerequisites for successful periodontal and implant procedures. The aim of this study was to provide evidence-based time frames for various procedures pertaining to periodontal and implant treatment. A literature review was conducted to collect data on tissue healing; in areas in which data were lacking, the viewpoints of experienced clinicians were solicited to establish a consensus. This review reports recommended time frames for the healing processes associated with surgical crown-lengthening procedures (both functional and esthetic), fresh socket management, alveolar ridge management, soft tissue management, sinus floor augmentation, implant loading, and peri-implant defect management.

Treatment of peri-implantitis using nonsurgical debridement combined with bioresorbable doxycycline nanospheres: a case report with 3-year follow-up.

Treatment of peri-implant diseases focuses on reducing the bacterial load and consequent infection control. The use of local antimicrobials as an adjunct to mechanical therapy may result in a better outcome. Among antimicrobials, doxycycline stands out because of its local modulation of cytokines, microbial reduction, and clinical parameters in the treatment of periodontal diseases. The objective of this case report was to describe the combined application of mechanical debridement and bioresorbable doxycycline-loaded nanospheres for the treatment of peri-implantitis in a 71-year-old man. At the 3-year evaluation, the peri-implant tissues had improved, showing decreased probing depths, an absence of bleeding on probing, and no suppuration. This case report highlights the importance of supportive therapy, which is essential for the long-term success of peri-implantitis treatment.

Peri-implantitis with a potential axis to brain inflammation: an inferential review.

Peri-implantitis (PI) is a chronic, inflammatory, and infectious disease which affects dental implants and has certain similarities to periodontitis (PD). Evidence has shown that PD may be related to several types of systemic disorders, such as diabetes and insulin resistance, cardiovascular diseases, respiratory tract infections, adverse pregnancy outcomes, and neurological disorders. Furthermore, some types of bacteria in PD can also be found in PI, leading to certain similarities in the immunoinflammatory responses in the host. This review aims to discuss the possible connection between PI and neuroinflammation, using information based on studies about periodontal disorders, a topic whose connection with systemic alterations has been gaining the interest of the scientific community. Literature concerning PI, PD, and systemic disorders, such as neuroinflammation, brain inflammation, and neurological disorder, was searched in the PubMed database using different keyword combinations. All studies found were included in this narrative review. No filters were used. Eligible studies were analyzed and reviewed carefully. This study found similarities between PI and PD development, maintenance, and in the bacterial agents located around the teeth (periodontitis) or dental implants (peri-implantitis). Through the cardiovascular system, these pathologies may also affect blood-brain barrier permeability. Furthermore, scientific evidence has suggested that microorganisms from PI (as in PD) can be recognized by trigeminal fiber endings and start inflammatory responses into the trigeminal ganglion. In addition, bacteria can traverse from the mouth to the brain through the lymphatic system. Consequently, the immune system increases inflammatory mediators in the brain, affecting the homeostasis of the nervous tissue and vice-versa. Based on the interrelation of microbiological, inflammatory, and immunological findings between PD and PI, it is possible to infer that immunoinflammatory changes observed in PD can imply systemic changes in PI. This, as discussed, could lead to the development or intensification of neuroinflammatory changes, contributing to neurodegenerative diseases.

Metabolic profiling of peri-implant crevicular fluid in peri-implantitis.

OBJECTS: This study aims to explore the etiology of peri-implantitis by comparing the metabolic profiles in peri-implant crevicular fluid (PICF) from patients with healthy implants (PH) and those with peri-implantitis (PI). MATERIALS AND METHODS: Fifty-six patients were enrolled in this cross-sectional study. PICF samples were collected and analyzed using both non-targeted and targeted metabolomics approaches. The relationship between metabolites and clinical indices including probing depth (PD), bleeding on probing (BOP), and marginal bone loss (MBL) was examined. Additionally, submucosal microbiota was collected and analyzed using 16S rRNA gene sequencing to elucidate the association between the metabolites and microbial communities. RESULTS: Significant differences in metabolic profiles were observed between the PH and PI groups, with 179 distinct metabolites identified. In the PI group, specific amino acids and fatty acids were significantly elevated compared to the PH group. Organic acids including succinic acid, fructose-6-phosphate, and glucose-6-phosphate were markedly higher in the PI group, showing positive correlations with mean PD, BOP, and MBL. Metabolites that increased in the PI group positively correlated with the presence of Porphyromonas and Treponema and negatively with Streptococcus and Haemophilus. CONCLUSIONS: This study establishes a clear association between metabolic compositions and peri-implant condition, highlighting enhanced metabolite activity in peri-implantitis. These findings open avenues for further research into metabolic mechanisms of peri-implantitis and their potential therapeutic implications.

Early Implant Failure: A Meta-Analysis of 7 Years of Experience.

Background: The use of dental implant rehabilitation in the treatment of complete and partial edentulism has become an integral treatment today. This treatment is performed on healthy patients, but in some situations, also on those with associated general ailments. The presence of associated conditions increases the degree of difficulty of this type of treatment and tests the doctor's ability to manage the clinical case. The purpose of the study was to perform a meta-analysis of dental implants inserted over seven years and evaluate early implant failure in correspondence with age, sex, region of insertion, type of implant, and general state of health. Methods: A retrospective study was performed over 7 years of experience. For the study, 213 patients who fit the established inclusion criteria were selected. Patients were grouped taking into account age, sex, the type of implant used, and general associated conditions. The collected data were analyzed using IBM SPSS STATISTICS 25.0 for windows Results: There were no highlighted situations in which the rejection of the dental implant occurred 10 days postoperatively or later during the healing period. Conclusions: Our results confirm and strengthen the existing data in the specialized literature, especially those related to the loss of implants in patients with associated general diseases.

The effect of individuals' oral hygiene habits and knowledge levels on peri-implant health and disease: a questionnaire-based observational study.

BACKGROUND: Peri-implant disease and health are associated with microbial dental plaque. Therefore, oral hygiene plays a role in preventing and treating these diseases. This study aimed to determine the relationships among knowledge of peri-implant status, oral hygiene habits, and peri-implant disease and health. METHODS: A total of 144 implants in nonsmokers with controlled systemic disease were included in the study. Peri-implant disease and the conditions of the implants were determined with periodontal indices and radiographs based on the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions and The EFP S3 level clinical practice guideline. Individuals were asked 66 questions regarding demographic information, oral hygiene habits and history, and knowledge of peri-implant diseases. One-way ANOVA was used to compare the three peri-implant disease and condition categories. RESULTS: There was a significant difference between groups regarding toothpaste type (p < 0.05). Gum protection toothpaste was greater in the peri-implant health group. Patients' use of interdental products was very low; often, no products were used for implant prosthesis. There was no significant difference among the groups regarding oral hygiene product use or oral hygiene habits (p > 0.05). There was a significant difference between groups regarding frequency of visit (p < 0.05). The frequency of visits to the dentist for pain was greater for individuals with peri-implantitis. There is a significant difference between the groups' answers for the causative and initiating factors of peri-implant disease (p < 0.05). The peri-implant health group answered that microbial dental plaque is the most crucial initiating factor of peri-implant diseases, and bleeding on probing is the most critical determinant of peri-implant diseases at a higher rate than the other groups. CONCLUSIONS: Patients' oral hygiene habits and knowledge levels are almost similar according to peri-implant status. Knowledge does not reflect a patient's oral hygiene behavior. Clinicians should ensure that individuals' oral hygiene practices align with their increased awareness regarding peri-implant illnesses.

Construction of a diagnostic model based on random forest and artificial neural network for peri-implantitis.

OBJECTIVES: This study aimed to reveal critical genes regulating peri-implantitis during its development and construct a diagnostic model by using random forest (RF) and artificial neural network (ANN). METHODS: GSE-33774, GSE106090, and GSE57631 datasets were obtained from the GEO database. The GSE33774 and GSE106090 datasets were analyzed for differential expression and functional enrichment. The protein-protein interaction networks (PPI) and RF screened vital genes. A diagnostic model for peri-implantitis was established using ANN and validated on the GSE33774 and GSE57631 datasets. A transcription factor-gene interaction network and a transcription factor-micro-RNA (miRNA) regulatory network were also established. RESULTS: A total of 124 differentially expressed genes (DEGs) involved in the regulation of peri-implantitis were screened. Enrichment analysis showed that DEGs were mainly associated with immune receptor activity and cytokine receptor activity and were mainly involved in processes such as leukocyte and neutrophil migration. The PPI and RF screened six essential genes, namely, CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8. The receiver operating characteristic curve (ROC) indicated that the ANN model had an excellent diagnostic performance. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 may be a key miRNA. CONCLUSIONS: The diagnostic model of peri-implantitis constructed by RF and ANN has high confidence, and CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8 are potential diagnostic markers. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 plays a vital role as a critical miRNA.

Performance evaluation of carbon quantum dots impregnated glass ionomer cement to avoid peri-implant disease.

Dental cement residues exacerbate peri-implant tissue irritation and peri-implantitis. The present study aims to evaluate the cytotoxicity, physiochemical, optical, and rheological properties of Carbon Quantum Dots (CQDs) impregnated Glass Ionomer Cement (GIC). Surface passivated fluorescent CQDs were synthesized using citric acid via thermal decomposition and blended with GIC. Characterization studies and rheological measurements were made to evaluate their performance. 3D-printed dental implant models cemented with GIC and GIC-CQD were compared to analyze excess cement residues. MTT assay was performed with human Dental Pulp Stem Cells (hDPSCs) and statistically analyzed using ANOVA and Tukey's test. CQDs with a particle dimension of ~2 nm were synthesized. The amorphous property of GIC-CQD was confirmed through XRD. The fluorescence properties of GIC-CQD showed three times higher emission intensity than conventional GIC. GIC-CQD attained maturation with a setting time extended by 64 seconds than GIC. Cement residue of size 2 mm was detected with a UV light excitation at a distance between 5 to 10 cm. Biocompatibility at 0.125 mg/ml dilution concentrations of GIC-CQD showed viability greater than 80% to hDPSCs. For the first time, we report that CQDs-impregnated GIC is a unique and cost-effective strategy for in-situ detection of excess cement rapidly using a hand-held device. A novel in-situ rapid detection method enables the dentist to identify residual cement of size less than 2 mm during the implantation. Therefore, GIC-CQD would replace conventional GIC and help in the prevention of peri-implant diseases.

Immune cell composition and inflammatory profile of human peri-implantitis and periodontitis lesions.

Peri-implantitis and periodontitis are common oral inflammatory diseases, which seem to exhibit critical differences in some of their molecular features. Thus, we assessed the immune cell composition of peri-implantitis and periodontitis lesions and the corresponding inflammatory profile in soft tissues and crevicular fluid. Peri-implantitis, periodontitis and control patients were recruited (n=62), and soft tissue biopsies were collected during surgery. Crevicular fluid around implant or tooth was collected. The proportions of major immune cell populations in tissues were analyzed by flow cytometry, and the inflammatory profile in tissue and crevicular fluid by a multiplex immunoassay. No significant difference was seen between peri-implantitis and periodontitis lesions in the proportions of immune cells. Peri-implantitis tissues showed an increased frequency of B cells in comparison with control tissues, along with higher levels of IL-1ß, TNF-α, IL-4, and BAFF in tissue and crevicular fluid. Moreover, TNF-α, IL-17A and BAFF were higher in peri-implantitis tissues, but not in periodontitis, than in control tissues. The immune cell composition did not differ significantly between peri-implantitis and periodontitis, but an enhanced inflammatory profile was seen in peri-implantitis tissue. Peri-implantitis lesions were enriched in B cells, and displayed increased levels of IL-1ß, TNF-α, IL-4, and BAFF in both tissue and crevicular fluid.

The effect of nicotine-containing products on peri-implant tissues: A systematic review and network meta-analysis.

INTRODUCTION: Smokers have a higher chance of developing peri-implant diseases and are therefore considered an at-risk population. Our aim was to compare peri-implant characteristics in users of electronic cigarettes (EC), waterpipes (WP), cigarettes (CS), smokeless tobacco (ST), and non-smokers (non-users of any nicotine and tobacco product; NS). METHODS: A systematic search of four electronic databases (PubMed, EMBASE, Web of Science, CENTRAL) was performed until April 2023, restricted to English language. Thirty-nine observational studies were included in the qualitative synthesis, of which 32 studies were included in a Bayesian network meta-analysis. Using a predesigned form, two researchers independently collected data about marginal bone loss (MBL), probing pocket depth (PPD), plaque index (PI), bleeding on probing (BOP), modified plaque index (mPI), probing pocket depth > 4mm (PPD>4), gingival index (GI), peri-implant sulcular fluid (PISF) volume, and TNF-α and IL-1ß levels. QUIPS and CINeMA were used to evaluate the risk of bias and certainty of evidence. RESULTS: NS had the smallest MBL. Most nicotine-containing product users had significantly higher MBL (CS, MD:1.34 CrI: 0.85, 1.79; WP, MD:1.58 CrI: 0.84, 2.35; ST, MD:2.53, CrI: 1.20, 3.87) than NS. EC did not show significant difference compared to NS (MD:0.52 CrI: -0.33, 1.36). In secondary outcomes NS were ranked in first place. Subset analysis based on smoking habit, implant duration, and maintenance control revealed no differences in ranking probability. CONCLUSION: Most nicotine-containing product users presented worse peri-implant parameters compared to non-smokers, while EC users did not show significant differences to NS in many outcomes. IMPLICATION: Alternative nicotine-containing products are gaining popularity and are often considered less harmful by the general public compared to traditional cigarettes. This is the first network meta-analysis comparing users of four nicotine-containing products and non-smokers. This study shows that CS, WP and ST have a detrimental effect on the overall health of peri-implant tissues. EC users also presented inferior parameters compared to NS, however, the difference was not significant in many outcomes. It is essential to educate patients who are using nicotine-containing products, and to provide proper maintenance and appropriate cessation support. Well-designed multi-armed studies are needed for direct comparison of different products, including heated tobacco products. Greater transparency of confounding factors is needed regarding smoking habit and oral hygiene.

Detection and comparison of neutrophil extracellular traps in tissue samples of peri-implantitis, periodontitis, and healthy patients: A pilot study.

OBJECTIVE: The aim of this study was to detect and compare the tissular expression of neutrophil extracellular traps (NETs) in peri-implant and periodontal samples of patients with peri-implantitis, periodontitis, and controls. MATERIALS AND METHODS: An observational study was performed on patients with peri-implantitis, periodontitis, and controls. Peri-implant and/or periodontal clinical examinations were performed on each participant. Tissue samples were collected during tooth/implant extraction for clinical reasons. Electron microscopy analysis, Picro-Sirius red staining, immunohistochemical (CD15), and immunofluorescence (citrullinated H3 and myeloperoxidase) techniques were performed to detect NET-related structures and the degree of connective tissue destruction, between the study groups. RESULTS: Sixty-four patients were included in the study: 28 peri-implantitis, 26 periodontitis, and 10 controls, with a total of 51 implants, 26 periodontal teeth, and 10 control teeth. Neutrophil release of nuclear content was observed in transmission electron microscopy. Immunohistochemical analysis showed a greater CD15 expression in both peri-implantitis and periodontitis compared to controls (p < 0.001), and peri-implantitis presented lower levels of connective tissue and collagen compared to both periodontitis (p = 0.044; p < 0.001) and controls (p < 0.001). Immunofluorescence showed greater citH3 expression in peri-implantitis than the one found in both periodontitis (p = 0.003) and controls (p = 0.048). CONCLUSIONS: A greater presence and involvement of neutrophils, as well as a greater connective tissue destruction were observed in cases of peri-implantitis. A higher expression of NET-related markers was found in mucosal samples of peri-implantitis compared to periodontitis and controls.

Analysis of the Association of IL-1A, IL-1B and IL-1RN Polymorphisms with Peri-implantitis in a Portuguese Population.

PURPOSE: The aim of this study was to investigate whether genetic variations in cytokine genes involved in the pathogenesis of peri-implantitis, could be associated with its occurrence, an issue that remains controversial and may vary according to the population evaluated. MATERIAL AND METHODS: A cross-sectional analytical study was carried out on 102 Portuguese Caucasian individuals divided into two groups: 43 individuals with peri-implantitis and 59 individuals with peri-implant health. Samples from the buccal mucosa were obtained and genetic analysis was performed using the real-time polymerase chain reaction (PCR) technique for IL-1A and IL-1B and using PCR and restriction fragment length polymorphism analysis for IL-1RN. RESULTS: The IL-1A -889 C/T polymorphism showed a higher prevalence of the less common allele (T allele) in cases of peri-implantitis than in healthy cases (27.9% vs 16.9%, respectively), but without statistical significance (p = 0.060). For the IL-1B +3954 C/T and IL-1RN (variable number of tandem repeats) polymorphisms, the analysis revealed that the allele and genotype frequencies did not differ significantly between groups. There was a significant association between a history of periodontitis and peri-implantitis (p = 0.020). CONCLUSIONS: The genetic polymorphisms evaluated had no influence on the occurrence of periimplantitis in the population studied. Further research into genetic variations in different populations is needed to elucidate the role of genetic factors in the onset and progression of periimplant disease.