Clinical, microbiological and osteoimmunological findings in different peri-implant conditions - A cross-sectional study.

OBJECTIVES: The aim of this study was to assess the prevalence of certain microbiota and their potential correlation with clinical parameters, expression of proinflammatory cytokines, Notch signalling pathway molecules and bone remodelling mediators among different peri-implant conditions. MATERIALS AND METHODS: Included participants had at least one dental implant minimally 1 year in function. They were divided into peri-implantitis (PI), peri-implant mucositis (PM) and healthy implants (HIs) groups. Prevalence of P. ginigvalis, Fusobacterium spp., EBV and C. albicans was detected in participants' crevicular fluid (CF) using quantitative real-time polymerase chain reaction, different markers' expression, as well as clinical data, were correlated with the microbial presence. RESULTS: CF samples taken from one chosen implant from each of the 102 participants were analyzed. Significantly higher levels of P. gingivalis were found in PI compared with HI (p = .012) and PM (p = .026). Fusobacterium spp. was also more prevalent in PI (p = .041) and PM (0.008) than in HI. P. gingivalis was a predictor of PPDi (p = .011, R2 = 0.063) and CALi (p = .049, R2 = 0.038). A positive correlation was found in PI for the level of Fusobacterium spp. and TNFα expression (ρ = 0.419, p = .017) while in PM, P. gingivalis and Notch 2 expression were correlated (ρ = 0.316, p = .047). CONCLUSIONS: P. gingivalis appears to be involved in the osteolysis in patients with PI, while the positive correlation of its level with Notch 2 expression in patients with PM suggests a potential involvement of P. gingivalis in the progression of PM into PI.

Effect of Donor Site Selection for Fat Grafting on the Yield and Viability of the Stromal Vascular Fraction.

BACKGROUND: The efficacy of stromal vascular fraction (SVF) treatment, or stem cell treatment, directly depends on the SVF cell count and the cells' viability. The SVF cell count and viability are in direct correlation with the adipose tissue harvesting site that yields SVF cells, making this research a contribution to developing tissue guidance. OBJECTIVES: The aim of this study was to investigate the importance of harvesting subcutaneous adipose tissue-derived SVF cells on the concentration and viability of SVF. METHODS: Adipose tissue was collected by vibration-assisted liposuction from the regions of the upper and lower abdomen, lumbar region, and inner thigh region. With the semiautomatic UNISTATION 2nd Version system, the obtained fat was chemically processed (with collagenase enzyme) and a concentrate of SVF cells was obtained by centrifugation. These samples were then analyzed with the Luna-Stem Counter device to measure the number and viability of SVF cells. RESULTS: When comparing the regions of the upper abdomen, lower abdomen, lumbar region, and inner thigh, the highest concentration of SVF was found in the lumbar region, specifically at an average of 97,498.00 per 1.0 mL of concentrate. The lowest concentration was found in the upper abdominal region. When ranking the viability values, the highest cell viability of SVF was observed in the lumbar region, measuring 36.6200%. The lowest viability was found in the upper abdominal region, measuring 24.4967%. CONCLUSIONS: By comparing the upper and lower abdominal, lumbar, and inner thigh regions, the authors have come to the conclusion that, on average, the largest number of cells with the highest viability was obtained from the lumbar region.

Notch signalling cascade and proinflammatory mediators in peri-implant lesions with different RANKL/OPG ratios-An observational study.

BACKGROUND & OBJECTIVE: Notch signaling pathway has been linked to bone loss in periodontitis and peri-implantitis. This research aimed to determine the Notch signaling molecules expression levels (Notch1, Notch2, Jagged1, Hes1, and Hey1), along with bone remodeling mediators (RANKL and OPG) and proinflammatory cytokines (TNF-α, IL-17, IL-1ß, and IL-6) in patients with peri-implant diseases. The aforementioned markers' expression was evaluated in patients with different RANKL/OPG ratios. METHODS: Fifty patients with peri-implantitis (PI group) and 45 patients with peri-implant mucositis (PM group) were enrolled. Relative gene expression levels of investigated molecules were determined by reverse transcriptase-real-time polymerase chain reaction. On the basis of RANKL/OPG ratio, all peri-implant lesions were divided into subgroups: RANKL-predominant (RANKL > OPG) and OPG-predominant (RANKL < OPG). Clinical periodontal parameters (probing depth-PD, bleeding on probing-BOP, clinical attachment level-CAL and plaque index-PLI), were recorded for each patient around every tooth, and around placed implants (PDi, BOPi, CALi, PLIi). RESULTS: RANKL-predominant PM patients exhibited higher expression levels of Notch2 (p = .044) and Hey1 (p = .005) compared to OPG-predominant lesions. In all RANKL-predominant cases, Hey1 (p = .001), IL-1ß (p = .005), IL-6 (p = .002) were overexpressed in PI comparing to PM, accompanied with significantly higher PDi, CALi and PLIi in PI than PM (p = .001, p = .001 and p = .009). CONCLUSIONS: Notch2 upregulation in RANKL-predominant PM lesions could be an important contributor to alveolar bone resorption and represent a predictor of PM to PI transition. Similarly, the overexpression of IL-1ß and IL-6 might provide an osteoclastogenic environment in PI RANKL-predominant lesions.

Notch down-regulation and inflammatory cytokines and RANKL overexpression involvement in peri-implant mucositis and peri-implantitis: A cross-sectional study.

OBJECTIVES: Notch signaling pathway, known to influence bone resorption in several oral diseases, has not been analyzed in peri-implantitis yet. Therefore, the aims of the present study were to determine the levels of Notch cascade, bone remodeling mediators, and pro-inflammatory cytokines, in conjunction with clinical parameters, in subjects with peri-implant mucositis and peri-implantitis. MATERIAL AND METHODS: Clinical parameters: peri-implant probing depth, bleeding on probing, suppuration on probing, and plaque index (PI) were recorded. Samples were collected from 130 participants, divided into peri-implantitis (PI), peri-implant mucositis (PM), and healthy implants (HI) group. Relative expression levels (REL) of Notch 1, Notch 2, Jagged 1, Hes 1, Hey 1, TNF-α, IL-17, IL-1ß, IL-6, RANKL, and OPG mRNA were determined by reverse transcriptase-real-time polymerase chain reaction. Quantitation of Notch 1, Il-17, and IL-6 proteins was performed using ELISA assays. RESULTS: All clinical parameters were significantly higher in PI compared to HI. Significant decrease of Notch 1, and higher REL of Hey 1, IL-1ß, IL-6, and RANKL were found in PI compared to HI. PM showed significant increase of IL-1ß REL in comparison with HI. In PI versus PM, significantly higher REL was found for Hey 1, TNF-α, IL-17, IL-1ß, IL-6, and RANKL. Additionally, higher protein concentrations of IL-6 and IL-17 were detected in PI versus PM and versus HI group. CONCLUSION: The combined effect of Notch 1 down-regulation and elevated expression of some key inflammation modulators might result in osteoclast activity increase and subsequent osteolysis in peri-implantitis.

Anatomy of septocutaneous blood vessels of the anterior forearm.

Aim To measure a calibre of radial and ulnar septocutaneous perforators at the anterior forearm, and to count its number in proximal, middle and distal thirds. Methods The study was conducted on 50 fresh amputated forearms (trauma, tumours) in the period between January 2012 and December 2021. Forearms were collected from several hospitals in Belgrade, and analysed at the Institute of Anatomy, Medical School, University of Belgrade, Serbia. Injection of ink-gelatin and fine dissection of autopsy material was performed on 30 forearms, and corrosion method with injecting methyl methacrylate for 3D analysis on the other 20 forearms. Results A mean calibre of septocutaneous perforators on the radial artery was 0.53±0.46 mm (0.2-0.85). Averagely, there were 8.1 radial artery septocutaneous perforators - two perforators on the proximal third, 3.7 on the middle third, and 2.7 on the distal third. The mean calibre of ulnar artery perforators was 0.65±0.35 mm (0.18-1.8). The average number of septocutaneous perforators of the ulnar artery was 5.6; 1.2 on the proximal third, two on the middle third, and 2.2 on distal third. Conclusion Determination of the origin, calibre and spreading directions of the arterial septocutaneous perforators on the anterior forearm provide quantification of data about arborisation of radial and ulnar septocutaneous perforators at the anterior forearm. Clinical relevance of those anatomical data is in defining of safe locations and dimensions of forearm fasciocutaneous flaps in plastic surgery.

Impact of Notch signalling molecules and bone resorption regulators on clinical parameters in periodontitis.

BACKGROUND AND OBJECTIVE: Notch signalling cascade has recently been connected to alveolar bone resorption in periodontitis. Hence, the present cross-sectional study aimed to analyze the expression of Notch signalling pathway (Notch 1, Notch 2, Jagged 1, Hes 1, Hey 1) and periodontitis-related (tumor necrosis factor alpha- TNF-α, interleukin 17-IL-17, receptor activator of nuclear factor-kappa B ligand-RANKL, osteoprotegerin-OPG) molecules and correlate it with clinical parameters in aggressive (AP) and chronic (CP) periodontitis. Additionally, the aforementioned markers' expression was evaluated in periodontitis patients with different RANKL/OPG ratios. MATERIAL AND METHODS: Eighty patients were enrolled either in AP or CP group. Clinical attachment level (CAL), bleeding on probing (BOP), periodontal probing depth (PPD) and plaque index (PI) were recorded for each patient. Total RNA was extracted from gingival crevicular fluid samples. Relative gene expression of investigated markers was determined by reverse transcriptase-real-time polymerase chain reaction. RESULTS: Significantly higher values of PPD were observed in AP compared to CP (P = .010). Negative correlations between OPG and CAL, and OPG and PI, were found in AP (P = .045, P = .006, respectively), while Hey 1 and PI had a positive correlation (P = .049). In multivariate linear regression analysis, OPG and Notch 2 were predictors of CAL in AP group. TNF-α and IL-17 were higher in RANKL predominant than in OPG predominant cases (P = .007, P = .001, respectively). In RANKL predominant lesions Notch 1 and Jagged 1 were down-regulated in AP compared to CP patients (P = .010, P = .025, respectively). CONCLUSION: The present study demonstrated that changes in Notch 2 expression affected CAL in AP cases hence this molecule could be considered as a contributor to alveolar bone loss. In RANKL-activated settings, the down-regulation of Notch 1 might participate in more severe bone resorption in AP.

The use of collagen porcine dermal matrix and connective tissue graft with modified coronally advanced tunnel technique in the treatment of multiple adjacent type I gingival recessions: A randomized, controlled clinical trial.

OBJECTIVE: To assess the clinical efficacy and esthetic outcome of porcine-derived dermal collagen matrix in comparison with connective tissue graft in the treatment of multiple adjacent gingival recessions (MAGR), 6 and 12 months after the surgery. MATERIALS AND METHODS: Twenty patients with bilateral type I MAGR were treated randomly with porcine-derived dermal collagen matrix (test site) or connective tissue graft (control site) in combination with a modified coronally advanced tunnel technique. The primary objectives were to evaluate the mean and complete root coverage. The secondary objectives were to assess keratinized tissue width, gingival thickness gain, and root coverage esthetic score. RESULTS: Six and 12 months postoperatively, both groups achieved significant improvements in all clinical parameters compared to baseline, with no statistically significant differences between the groups. Mean root coverage change (Δ12m - 6 m) was statistically significant between the groups in favor of connective tissue graft, and twice as many patients exhibited a complete coverage of all recessions in the control group than the test group. CONCLUSION: The porcine-derived dermal collagen matrix combined with a modified coronally advanced tunnel technique resulted in satisfactory clinical and esthetic outcomes, which were similar to connective tissue graft. CLINICAL SIGNIFICANCE: Porcine-derived dermal collagen matrix (XDM) may be proposed as a substitute for connective tissue graft in multiple adjacent recession treatment due to successful root coverage, a significant increase of gingival thickness, and high esthetic outcomes. The clinical benefits for the use of XDM could be: (a) second surgical wound avoidance, (b) patient discomfort decrease, and (c) lower complications' rate.

Ocular metastasis as initial presentation in breast cancer.

Two patients presented to their ophthalmologists with vision disturbances. On ocular examination, retinopathic lesions were observed. On subsequent examination, these lesions were diagnosed as metastases of breast cancer. Neither patient had a history of breast cancer. In patients with breast cancer and multiple metastases, ocular metastases are well described. However, the latter is uncommon as a presenting complaint.

Efficiency of photodynamic therapy in the treatment of peri-implantitis ­ A three-month randomized controlled clinical trial.

Introduction: Peri-implantitis is an inflammatory lesion of peri-implant tissues. Eradication of the causative bacteria and decontamination of the implant surface is essential in achieving predictable and stabile clinical results. Photodynamic therapy (PDT) is non-invasive adjuvant therapeutic method to surgery in the treatment of bacterial infection. Objective: The aim of this study was to evaluate early clinical and microbiological outcomes of periimplantitis after surgical therapy with adjuvant PDT. Methods: Fifty-two diagnosed peri-implantitis sites were divided into two groups. PDT was used for decontamination of implant surface in the study group; in the control group, chlorhexidine gel (CHX) followed by saline irrigation was applied. Several clinical parameters were recorded before the treatment (baseline values) and three months after surgical treatment. Samples for microbiological identification were collected before therapy, during the surgical therapy (before and after decontamination of implant surface), and three months thereafter, and analyzed with identification systems using biochemical analysis. Results: The use of PDT resulted in significant decrease of bleeding on probing in comparison to CHX (p < 0.001). It showed significant decontamination of implant surfaces with complete elimination of anaerobic bacteria immediately after surgical procedure and three months later. Conclusion: The results indicate that PDT can be used as an adjuvant therapy to surgery for decontamination of implant surface and surrounding peri-implant tissues within the treatment of peri-implantitis.

The Association Between Periodontal Inflammation and Labor Triggers (Elevated Cytokine Levels) in Preterm Birth: A Cross-Sectional Study.

BACKGROUND: Periodontitis is considered to be a risk factor for preterm birth. Mechanisms have been proposed for this pathologic relation, but the exact pathologic pattern remains unclear. Therefore, the objective of the present study is to evaluate levels of four major labor triggers, prostaglandin E2 (PGE2), interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α, in gingival crevicular fluid (GCF) and serum samples between women with preterm birth (PTB) and full-term birth (FTB) and correlate them with periodontal parameters. METHODS: PGE2, IL-1ß, IL-6, and TNF-α levels were estimated using enzyme-linked immunosorbent assays in GCF and serum samples collected 24 to 48 hours after labor from 120 women (60 FTB, 60 PTB). RESULTS: Women with PTB exhibited significantly more periodontitis, worse periodontal parameters, and increased GCF levels of IL-6 and PGE2 compared with the FTB group; there were no significant differences in serum levels of measured markers. GCF levels of IL-1ß, IL-6, and PGE2 and serum levels of TNF-α and PGE2 were significantly higher in women with periodontitis compared with periodontally healthy women. Serum levels of PGE2 were positively correlated with probing depth (PD) and clinical attachment level (CAL) as well as with GCF levels of TNF-α in women with PTB. CONCLUSIONS: Women with PTB demonstrated worse periodontal parameters and significantly increased GCF levels of IL-6 and PGE2 compared with those with FTB. Based on significant correlations among serum PGE2 and PD, CAL, and GCF TNF-α in PTB, periodontitis may cause an overall increase of labor triggers and hence contribute to preterm labor onset.

[Utilization of two different surgical techniques in gingival recession treatment: a comparative study].

INTRODUCTION: Gingival recession is a displacement of gingival margin apically to cement-enamel junction. OBJECTIVE: The aim of this study was to compare the results achieved with two different surgical procedures used in gingival recession treatment. METHODS: Ten patients with bilateral buccal recession on maxillary canines or premolars were included in the study. Professional teeth cleaning was performed before surgery. Recession on the experimental side was treated with connective tissue graft in combination with coronally advanced, split thickness flap (tunnel technique). Control side recession was treated with connective tissue graft in combination with trapezoidal coronally advanced, full thickness flap. Coin toss was used for side decision. The following parameters were evaluated before surgery and 6 months post-op: Vertical Recession Dimension, Clinical Attachment Level, Apico-coronal width of the keratinized tissue, Healing index (Laundry), RES index, and Patient evaluation of esthetic results. Student's t-test was used for statistical analysis. RESULTS: Six months after surgery, mean root coverage was 91.5 +/- 14.1% and 90.1 +/- 14.6% on the experimental and on the control side, respectively. RES index, Healing index (Laundry) and Patient Subjective evaluation of esthetic results showed significantly better results (p < 0.05). CONCLUSION: Both surgical procedures produce highly successful clinical results based on evaluated parameters, but this tunnel technique provides significantly better esthetic results.

Receptor activator of nuclear factor kappa B (RANK) as a determinant of peri-implantitis.

BACKGROUND/AIM: Peri-implantitis presents inflammatory process that affects soft and hard supporting tissues of osseointegrated implant based on inflammatory osteoclastogenesis. The aim of this study was to investigate whether receptor activator of nuclear factor kappa B (RANK) concentrations in peri-implant crevicular fluid could be associated with clinical parameters that reflect inflammatory nature of peri-implantitis. METHODS: The study included 67 patients, 22 with diagnosed peri-implantitis, 22 persons with healthy peri-implant tissues and 23 patients with periodontitis. Clinical parameters from each patient were recorded and samples of peri-implant/gingival crevicular fluid were collected for the enzyme-linked immunosorbent assay (ELISA) analysis. RESULTS: RANK concentration was significantly increased in samples from the patients with peri-implantitis when compared to healthy implants (p < 0.0001), where the average levels were 9 times higher. At the same time RANK concentration was significantly higher in peri-implantitis than in periodontitis sites (p < 0.0001). In implant patients pocket depths and bleeding on probing values were positively associated with high RANK concentrations (p < 0.0001). CONCLUSION: These results revealed association of increased RANK concentration in samples of peri-implant/gingival crevicular fluid with peri-implant inflammation and suggests that RANK could be a pathologic determinant of peri-implantitis, thereby a potential parameter in assessment of peri-implant tissue inflammation and a potential target in designing treatment strategies.

Impact of interleukin 1 gene polymorphism and smoking on long-term stability following gingival recession treatment.

Risk factors such as smoking, genetic factors, and tissue biotype play an important role in the etiology, predictability, and long-term stability of gingival recession treatment. This study was designed to evaluate the influence of interleukin 1 (IL-1) polymorphism and smoking on the stability of gingival recession treatment after 1 and 3 years. All patients (n = 55) were treated for type I and II recession defects using a connective tissue graft. Clinical evaluations were performed, which included assessment of vertical recession depth, gingival inflammation, and clinical attachment level. A fingerstick blood sample was collected using specially provided DNA filter paper and mailed for processing in a laboratory using polymerase chain reaction-based methodology. The results indicated that 19 subjects were genotype positive (34.5%). Treatment of the localized recessions was effective and provided a similar amount of coverage in genotype-positive and genotype-negative subjects within smoking and nonsmoking groups after 1 year. In a 3-year period, nonsmoking patients with positive IL-1 genotype lost approximately 20% of the root coverage gained at 1 year and were almost four times more inferior compared with genotype-negative patients. Patients who smoked and had a positive IL-1 genotype lost approximately 35% of the gained root coverage. IL-1 polymorphism and smoking habit did not affect gingival recession treatment at 1 year but had a great impact on long-term stability.

[The use of platelet-rich fibrin membrane in gingival recession treatment].

INTRODUCTION: Fibrin, fibronectin, platelet derived growth factor, and transforming growth factors from platelet concetrate are crucial for tissue reparation and regeneration. OBJECTIVE: This study was designed to evaluate clinical effectiveness of activated platelet-rich fibrin (PRF) membrane in treatment of gingival recession. METHODS: 19 gingival recessions Miller class I or II were treated with a coronally advanced flap and the PRF membrane (PRF group). Following the elevation of the flap, bone and root surfaces were covered with the PRF membrane. After suturing, the PRF membrane was covered with a coronally advanced flap. In the same patients, 19 other gingival recessions were treated with CTG in combination with the coronally advanced flap (the CTG group). Clinical recordings were made of vertical recession depth (VRD), probing depth (PD), clinical attachment level (CAL) and keratinized tissue width (KTW) before and 12 months after mucogingival surgical treatment. Clinical evaluation of healing events was estimated with recordings of the healing index (HI). Recordings of HI were performed in the 1st, 2nd and 3rd week post-surgically. RESULTS: Mean root coverage was significant in both groups (the PRF group 79.94% and the CTG group 88.56% %; p < 0.01). The difference between the two tested groups was not statistically significant. Results of the keratinized tissue width showed significant increase (p < 0.05) 12 months after the surgery in both, the PRF and CTG groups. Results of KTW showed statistical significance of recorded differences obtained in the two evaluated groups (p < 0.05). There was no statistical significance in reduction of PD and CAL recorded in the PRF and CTG groups. The values of HI recorded in the 1st and 2nd week postoperatively were significantly enhanced in the PRF group (p < 0.05). CONCLUSION: Results of this study confirm both procedures as effective with equivalence of clinical results in solving gingival recession problems. The utilization of the PRF resulted in a decreased postoperative discomfort and advanced tissue healing.

Implementation of contact definitions calculated by FEA to describe the healing process of basal implants.

AIMS: Bone structure around basal implants shows a dual healing mode: direct contact areas manifest primary osteonal remodeling, in the void osteotomy-induced spaces, the repair begins with woven bone formation. This woven bone is later converted into osteonal bone. The purpose of this study was to develop a model to accurately represent the interface between bone and basal implant throughout the healing process. The model was applied to the biological scenario of changing load distribution in a basal implant system over time. METHODS: Computations were made through finite element analysis using multiple models with changing boneimplant contact definitions which reflected the dynamic nature of the interface throughout the bony healing process. Five stages of bony healing were calculated taking into account the changes in mineral content of bone in the vicinity of the load transmitting implant surfaces. RESULTS: As the bony integration of basal implants proceeds during healing, peak stresses within the metal structure shift geographically. While bony repair may still weaken osteonal bone, woven bone has already matured. This leads to changes in the load distribution between and within the direct contact areas, and bone areas which make later contact with implant. CONCLUSIONS: This study shows that basal implants undergo an intrinsic shift of maximum stress regions during osseointegration. Fatigue testing methods in the case of basal implants must therefore take into account this gradual shift from early healing phase until full osseointegration is achieved.

The use of finite element analysis to model bone-implant contact with basal implants.

OBJECTIVE: The purpose of this study was to develop a model that accurately represents the interface between bone and basal implants throughout the healing process. STUDY DESIGN: The model was applied to the biological scenario of changing load distribution in a basal implant system over time. We did this through finite element analysis (FEA, or finite element method [FEM]), using multiple models with changing bone-implant contact definitions, which reflected the dynamic nature of the interface throughout the bony healing process. RESULTS: In the simple models, peak von Mises stresses decreased as the bone-implant-contact definition was changed from extremely soft contact (i.e., immature bone during early loading) to hard contact (i.e., mature bone). In upgraded models, which more closely approximate the biological scenario with basal dental implant, peak von Mises stresses decreased at the implant interface; however, they increased at the bone interface as a harder contact definition was modeled. Further, we found a shift in peak stress location within the implants during different contact definitions (i.e., different stages of bony healing). In the case of hard contact, the peak stress occurs above the contact surface, whereas in soft contact, the stress peak occurs in the upper part of the contact area between bone and the vertical shaft of the implant. Only in the extreme soft contact definitions were the peak stresses found near the base plate of the implant. CONCLUSION: Future FEM studies evaluating the functional role of dental implants should consider a similar model that takes into account bone tissue adaptations over time.