Differences between first- and second-generation autologous platelet concentrates.

Autologous platelet concentrates (APCs) applied alone or combined with other biomaterials are popular bioactive factors employed in regenerative medicine. The main biological rationale of using such products is to concentrate blood-derived growth factors and cells into the wound microenvironment to enhance the body's natural healing capacity. First-generation APC is represented by platelet-rich plasma (PRP). While different protocols have been documented for PRP preparation, they overall consist of two cycles of centrifugation and have important limitations related to the use of an anticoagulant first and an activator afterward, which may interfere with the natural healing process and the release of bioactive molecules. The second generation of platelet concentrates is represented by leukocyte and platelet-rich fibrin (L-PRF). L-PRF protocols involve a single centrifugation cycle and do not require the use of anticoagulants and activators, which makes the preparation more straight forward, less expensive, and eliminates potential risks associated with the use of activators. However, since no anticoagulant is employed, blood undergoes rapid clotting within the blood collection tube; hence, a timely management of L-PRF is crucial. This review provides an overview on the most documented protocols for APC preparations and critically discusses the main differences between first- and second-generation APCs in terms of cell content, protein release, and the formation of a 3D fibrin network. It appears evident that the inconsistency in reporting protocol parameters by most studies has contributed to conflicting conclusions regarding the efficacy of different APC formulations and has significantly limited the ability to interpret the results of individual clinical studies. In the future, the use of a standardized classification system, together with a detailed reporting on APC protocol parameters is warranted to make study outcomes comparable. This will also allow to clarify important aspects on the mechanism of action of APCs (like the role of leukocytes and centrifugation parameters) and to optimize the use of APCs in regenerative medicine.

Elucidating the molecular healing of intrabony defects following non-surgical periodontal therapy: A pilot study.

OBJECTIVE: To elucidate the molecular healing of intrabony defects following non-surgical periodontal therapy (NSPT) using gingival crevicular fluid (GCF). BACKGROUND DATA: Currently limited information is available regarding the GCF of intrabony defects and the change in biomarker levels in the GCF at early time points following treatment interventions. METHODS: Twenty-one patients (Periodontitis Stage III or IV) who have received NSPT, contributing one intrabony defect and one healthy site were included in this study. GCF sampling was performed at baseline, 1 day, 5 days and 3 months after NSPT. Multiplex bead immunoassays allowed the profiling of GCF for 27 markers, associated with inflammation and repair/regeneration. A mixed effects model with Bonferroni correction for multiple comparisons was employed to compare the changes in the levels of GCF markers over time. RESULTS: Following NSPT, changes were observed for several GCF markers, marked by significant increases 1 day post-intervention, before returning to baseline levels by 3 months. Specifically, GCF concentrations of IL-2, IL-4, IL-6, IL-8, MMP-1, MMP-3, TIMP-1 and FGFb significantly increased 1 day after NSPT. Signs of activation of cellular senescence were observed 1 day following treatment of intrabony defects, rapidly regressing by 5 days. CONCLUSION: Significant molecular changes are observed as early as 1 day following NSPT in intrabony defects, along with activation of cellular senescence.

All-cause and cause-specific mortality in US adults with periodontal diseases: A prospective cohort study.

AIM: This prospective cohort study investigated the association between periodontal diseases (PDs) and all-cause and cause-specific mortality. MATERIALS AND METHODS: We utilized adult participants recruited from six National Health and Nutrition Examination Survey cycles (1999-2014) and linked mortality data from the National Death Index up to December 2019. Baseline clinical periodontal examinations were performed by trained and calibrated examiners. All-cause and cause-specific mortality was modelled through multivariable Cox proportional hazards and Fine-Gray models to account for competing risks. All models were adjusted for demographic and lifestyle variables, clinical measurements and comorbidities. RESULTS: Overall, 15,030 participants were included, with a median length of follow-up of 9 years. Risk of all-cause mortality was 22% greater in people with PD than the control group (adjusted hazard ratio [HR]: 1.22, 95% confidence interval [CI]: 1.12-1.31). Risks of mortality by cardiovascular diseases (CVD), respiratory disease and diabetes were highest in participants with severe PD (CVD-sub-distribution HR [SHR]: 1.38, 95% CI: 1.16-1.64; respiratory-SHR: 1.62, 95% CI: 1.07-2.45; diabetes-SHR: 1.68, 95% CI: 1.12-2.53). CONCLUSIONS: Severe PD is associated with all-cause and cause-specific mortality among US adults after multivariable adjustment.

Is alveolar ridge preservation an overtreatment?

The morphology and dimensions of the postextraction alveolar ridge are important for the surgical and restorative phases of implant treatment. Adequate new bone formation and preservation of alveolar ridge dimensions following extraction will facilitate installation of the implant in a restorative position, while preservation of soft tissue contour and volume is essential for an aesthetic and implant-supported restoration with healthy peri-implant tissues. Alveolar ridge preservation (ARP) refers to any procedure that aims to: (i) limit dimensional changes in the alveolar ridge after extraction facilitating implant placement without additional extensive bone and soft tissue augmentation procedures (ii) promote new bone formation in the healing alveolus, and (iii) promote soft tissue healing at the entrance of the alveolus and preserve the alveolar ridge contour. Although ARP is a clinically validated and safe approach, in certain clinical scenarios, the additional clinical benefit of ARP over unassisted socket healing has been debated and it appears that for some clinicians may represent an overtreatment. The aim of this critical review was to discuss the evidence pertaining to the four key objectives of ARP and to determine where ARP can lead to favorable outcomes when compared to unassisted socket healing.

Bone regeneration in implant dentistry: Which are the factors affecting the clinical outcome?

The key factors that are needed for bone regeneration to take place include cells (osteoprogenitor and immune-inflammatory cells), a scaffold (blood clot) that facilitates the deposition of the bone matrix, signaling molecules, blood supply, and mechanical stability. However, even when these principles are met, the overall amount of regenerated bone, its stability over time and the incidence of complications may significantly vary. This manuscript provides a critical review on the main local and systemic factors that may have an impact on bone regeneration, trying to focus, whenever possible, on bone regeneration simultaneous to implant placement to treat bone dehiscence/fenestration defects or for bone contouring. In the future, it is likely that bone tissue engineering will change our approach to bone regeneration in implant dentistry by replacing the current biomaterials with osteoinductive scaffolds combined with cells and mechanical/soluble factors and by employing immunomodulatory materials that can both modulate the immune response and control other bone regeneration processes such as osteogenesis, osteoclastogenesis, or inflammation. However, there are currently important knowledge gaps on the biology of osseous formation and on the factors that can influence it that require further investigation. It is recommended that future studies should combine traditional clinical and radiographic assessments with non-invasive imaging and with patient-reported outcome measures. We also envisage that the integration of multi-omics approaches will help uncover the mechanisms responsible for the variability in regenerative outcomes observed in clinical practice.

Efficacy of biomaterials for lateral bone augmentation performed with guided bone regeneration. A network meta-analysis.

Bone regeneration is often required concomitant with implant placement to treat a bone fenestration, a dehiscence, and for contouring. This systematic review assessed the impact of different biomaterials employed for guided bone regeneration (GBR) simultaneous to implant placement on the stability of radiographic peri-implant bone levels at ≥12 months of follow-up (focused question 1), as well as on bone defect dimension (width/height) changes at re-assessment after ≥4 months (focused question 2). Only randomized controlled trials (RCTs) and controlled clinical trials (CCTs) that compared different biomaterials for GBR were considered. A Bayesian network meta-analysis (NMA) was performed using a random-effects model. A ranking probability between treatments was obtained, as well as an estimation of the surface under the cumulative ranking value (SUCRA). Overall, whenever the biological principle of GBR was followed, regeneration occurred in a predictable way, irrespective of the type of biomaterial used. A lower efficacy of GBR treatments was suggested for initially large defects, despite the trend did not reach statistical significance. Regardless of the biomaterial employed, a certain resorption of the augmented bone was observed overtime. While GBR was shown to be a safe and predictable treatment, several complications (including exposure, infection, and soft tissue dehiscence) were reported, which tend to be higher when using cross-linked collagen membranes.

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVES: Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence. MATERIALS AND METHODS: Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control. RESULTS: Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence. CONCLUSION: Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

Clinical efficacy of hand and power-driven instruments for subgingival instrumentation during periodontal surgical therapy: a systematic review.

OBJECTIVE: This systematic review aims to assess the available literature on the clinical efficacy of hand versus power-driven instruments for subgingival instrumentation during surgical periodontal therapy (ST). MATERIALS AND METHODS: A search of the literature was carried out on MEDLINE via Ovid, Embase, Web of Science, the Cochrane Database, LILACS, and Scopus. RCTs comparing the use of powered instruments (test) to hand scalers (control) for subgingival instrumentation in terms of changes in probing pocket depth (PPD) after surgical periodontal treatment were included and screened in duplicate. Descriptive synthesis of the data and risk of bias assessment were undertaken. RESULTS: Four RCTs met the inclusion criteria and were included in this systematic review. ST in all studies was performed by means of open flap debridement. Gracey curettes were the most commonly used hand instruments, while sonic and ultrasonic devices were used in the test group. Sites with initial PPD ≥ 6 mm had pocket reduction ranging from 2.93 to 4.89 mm in the control group and from 2.77 to 3.86 mm in the test group. All studies found no significant difference between the different types of instruments/devices in terms of PPD reduction. CONCLUSIONS: Despite the limited number of studies, both manual and power-driven instruments appear to be effective in reducing PPD after surgical treatment of periodontitis. CLINICAL RELEVANCE: Based on the findings of this systematic review, the clinician may make a decision whether to use manual or powered instruments during ST on a case-by-case basis and considering other factors, such as the risk of creating high concentrations of aerosols.

The influence of implant position and of prosthetic characteristics on the occurrence of peri-implantitis: a retrospective study on periapical radiographs.

OBJECTIVE: The present retrospective study aimed to investigate the influence of malposition on the occurrence of peri-implantitis. MATERIALS AND METHODS: The study included clinical records of systemically healthy patients with single and partial implant-supported rehabilitations and at least 1-year post-loading follow-up. The parameters collected included implant-related factors, patient-related factors, site-related factors, and prosthesis-related factors. The radiographic measurements were taken by using a dedicated software and the diagnosis of peri-implantitis was made based on all the available clinical and radiographic data. Descriptive statistics were provided for all variables. Following an exploratory approach, an implant-level analysis of factors influencing the occurrence of peri-implantitis was done through a multilevel multivariate logistic regression (mixed). RESULTS: A total of 180 implants belonging to 90 subjects were randomly selected. Malposition showed no statistically significant association with the occurrence of peri-implantitis. According to the multi-level analysis, the parameters that were significantly associated with peri-implantitis included presence / history of periodontitis (OR = 5.945, 95% CI: 1.093 - 32.334, P = 0.039) and presence of an emergence profile angle ≥ 45° (OR = 9.094, 95% CI: 2.017 - 40.995, P = 0.005). CONCLUSIONS: Implant malposition, as defined following Buser's criteria (2004), did not influence the occurrence of peri-implantitis in the selected cohort. Conversely, history of periodontitis and presence of a prosthetic emergence profile with an angle ≥ 45° were correlated to an increased risk of peri-implantitis.

Associations between Host Genetic Variants and Subgingival Microbiota in Patients with the Metabolic Syndrome.

Host genetic variants may affect oral biofilms, playing a role in the periodontitis-systemic disease axis. This is the first study to assess the associations between host genetic variants and subgingival microbiota in patients with metabolic syndrome (MetS); 103 patients with MetS underwent medical and periodontal examinations and had blood and subgingival plaque samples taken. DNA was extracted and processed, assessing a panel of selected single nucleotide polymorphisms (SNPs) first (hypothesis testing) and then expanding to a discovery phase. The subgingival plaque microbiome from these patients was profiled. Analysis of associations between host genetic and microbial factors was performed and stratified for periodontal diagnosis. Specific SNPs within RUNX2, CAMTA1 and VDR genes were associated with diversity metrics with no genome-wide associations detected for periodontitis severity or Mets components at p < 10-7. Severe periodontitis was associated with pathogenic genera and species. Some SNPs correlated with specific bacterial genera as well as with microbial taxa, notably VDR (rs12717991) with Streptococcus mutans and RUNX2 (rs3749863) with Porphyromonas gingivalis. In conclusion, variation in host genotypes may play a role in the dysregulated immune responses characterizing periodontitis and thus the oral microbiome, suggesting that systemic health-associated host traits further interact with oral health and the microbiome.

The efficacy of adjunctive periodontal therapies during supportive periodontal care in patients with residual pockets. A systematic review and meta-analysis.

While it is well-established that patients that develop signs of relapsing periodontitis in supportive periodontal care (SPC) will need to repeat subgingival instrumentation of the residual pockets, less certainty is available in terms of which protocol should be followed and whether the use of adjunctive therapies or physical agents might provide additional benefits to repeated instrumentation alone. The aim of this systematic review was therefore to assess whether repeating subgingival instrumentation in combination with adjunctive therapies (other than antimicrobials) might provide a significant benefit in terms of pocket closure, probing pocket depth (PPD) reduction or clinical attachment level (CAL) gain in patients during SPC with residual/relapsing pockets. Four databases were searched to identify randomized controlled trials (RCTs) and controlled clinical trials (CCTs) with a minimum follow-up of 3 months that investigated the use of adjunctive therapies (other than antimicrobials) in case of residual/relapsing pockets in patients in SPC since at least 3 months. Data extraction and risk of bias assessment were performed in the studies meeting the inclusion criteria and meta-analysis was performed when ≥3 studies assessing the same adjunctive therapy were identified. 12 studies (2 CCTs and 10 RCTs) were included for qualitative analysis. Meta-analysis was performed only for 3 studies on the adjunctive use of photodynamic therapy (PDT) and it indicated a nonsignificant benefit compared to the placebo in terms of PPD reduction and CAL gain at 3 months (weighted mean difference 0.07 and -0.03, respectively) and at 6 months of follow-up (weighted mean difference -0.09 and -0.18, respectively). While antiseptics did not provide significant benefits, one study on probiotics and one on the use of vitamin D and calcium supplementation showed significant improvements in periodontal parameters. There is currently insufficient/poor evidence to determine the efficacy of adjunctive strategies (other than antimicrobials) to improve the outcomes of SPC in case of residual/relapsing pockets.

Molecular profiling of intrabony defects' gingival crevicular fluid.

AIM: To profile, for the first time, the gingival crevicular fluid (GCF) of intrabony defects against a wide array of inflammatory and regenerative markers. MATERIALS AND METHODS: Twenty-one patients contributed one intrabony defect and one periodontally healthy site. Clinical and radiographic measures were obtained. GCF samples were analyzed with multiplex bead immunoassays over 27 markers previously identified by our group. Comparisons were performed using Wilcoxon matched-pairs signed-ranks tests, using a Bonferroni corrected α = 0.05/27 = 0.0019. RESULTS: Intrabony defect sites presented significantly increased GCF volume and disease-associated clinical and radiographic characteristics (p < .05). Intrabony defect sites presented significantly increased IL-1α, IL-1ß, IL-6, IFN-γ, and MMP-8 levels compared with periodontally healthy sites (p < .0019). For regeneration markers, significantly higher FGF basic and VEGF levels were observed (p < .0019). Notably, traits of cell senescence were identified for the first time in the GCF. CONCLUSIONS: The differentiation of intrabony defects from periodontally healthy control sites can be based on clinical and radiographic measures and on a differentiated GCF profile that is site-specific. Alongside catabolic processes, through significant up-regulation of inflammation and connective tissue remodeling, unique molecular characteristics of intrabony defects may render them a microenvironment amenable to regeneration. Traits of the senescence-associated secretory phenotype may suggest the existence of senescent cells during periodontal inflammation in intrabony defects.

Efficacy of tooth-supported compared to implant-supported full-arch removable prostheses in patients with terminal dentition. A systematic review.

AIMS: To compare tooth- (TSRP) and implant-supported (ISRP) removable prostheses in terms of abutment and prosthesis survival (PICO 1) and estimated cumulative survival of teeth/implants and prostheses (PICO 2) at ≥12-month post-prosthesis delivery in patients with stage IV periodontitis. MATERIALS AND METHODS: Five databases were searched to identify RCTs, CCTs, single arms, prospective cohort studies, case series and retrospective studies. Duplicate screening was performed, and ranges for abutment and prosthesis survival were calculated. RESULTS: Twenty-six studies were included in the qualitative assessment. Only one study with critical risk of bias comparing the two treatment modalities reported similar survival rates at 2 years. Overall, prospective studies on ISRPs indicated an implant survival rate ranging from 96.4% to 100% and a prosthesis survival rate of 100% with a follow-up from 12 to 54 months. Prospective studies on TSRPs indicated a tooth survival ranging from 85.71% to 100% at 1- to 10-years follow-up. CONCLUSIONS: The available evidence is of poor quality, and it does not allow to make robust conclusions on the efficacy of these rehabilitations in stage IV periodontitis patients. Particularly for TSRPs, careful patient selection is crucial and a certain number of biological and prosthetic complications should be expected.

Alveolar ridge preservation with guided bone regeneration or socket seal technique. A randomised, single-blind controlled clinical trial.

OBJECTIVES: To compare radiographic bone changes, following alveolar ridge preservation (ARP) using Guided Bone Regeneration (GBR), a Socket Seal (SS) technique or unassisted socket healing (Control). MATERIAL AND METHODS: Patients requiring a single rooted tooth extraction in the anterior maxilla, were randomly allocated into: GBR, SS and Control groups (n= 14/). Cone Beam Computed Tomography (CBCT) images were recorded post-extraction and at 4 months, the mid-buccal and mid-palatal alveolar ridge heights (BARH/PARH) were measured. The alveolar ridge width, cross-sectional socket and alveolar-process area changes, implant placement feasibility, requirement for bone augmentation and post-surgical complications were also recorded. RESULTS: BARH and PARH was found to increase with the SS (0.65 mm ± 1.1/0.65 mm ± 1.42) techniques, stabilise with GBR (0.07 mm ± 0.83/0.86 mm ±1.37) and decrease in the Control (-0.52 mm ± 0.8/-0.43 mm ± 0.83). Statistically significance was found when comparing the GBR and SS BARH (p = .04/.005) and GBR PARH (p = .02) against the Control. GBR recorded the smallest reduction in alveolar ridge width (-2.17 mm ± 0.84), when compared to the Control (-2.3 mm ± 1.11) (p = .89). A mid-socket cross-sectional area reduction of 4% (-2.27 mm2  ± 11.89), 1% (-0.88 mm2  ± 15.48) and 13% (-6.93 mm2  ± 8.22) was found with GBR, SS and Control groups (GBR vs. Control p = .01). The equivalent alveolar process area reduction was 8% (-7.36 mm2  ± 10.45), 6% (-7 mm2  ± 18.97) and 11% (-11.32 mm2  ± 10.92). All groups supported implant placement, with bone dehiscence noted in 57% (n = 4), 64%(n = 7) and 85%(n = 12) of GBR, SS and Control cases (GBR vs. Control p = .03). GBR had a higher risk of swelling and mucosal colour change, with SS associated with graft sequestration and matrix breakdown. CONCLUSION: GBR ARP was found to be more effective at reducing radiographic bone dimensional changes following tooth extraction.

Systematic review on the association between genetic polymorphisms and dental implant-related biological complications.

OBJECTIVES: The aim of this systematic review was to evaluate the association between specific genetic polymorphisms and dental implant-related biological complications in patients having a follow-up period of at least 12-months post-loading. MATERIAL AND METHODS: A sensitive search strategy was developed to identify implant-related genetic-association studies. This was performed by searching five databases. A three-stage screening (titles, abstract, full text) was carried out in duplicate and independently by two reviewers. Assessment was carried out according to the suggested scale for quality assessment of periodontal genetic-association studies and adapted to genetic analyses of implant-related studies leading to an overall final score 0-20 based on the summation of positive answers. RESULTS: The initial search resulted in 1838 articles. Sixty-seven full-text articles were assessed for eligibility and four studies met the defined inclusion criteria. IL-6 G174C, TNF-α -308, IL-1A-889 and IL-1B+3954 and CD14-159 C/T polymorphisms were evaluated. The quality assessment scores ranged from 6 to 11 positive answers from out of a maximum score of 20. The great heterogeneity among the studies did not allow a meta-analysis. CONCLUSIONS: The published evidence on genetic predisposition and implant biologic complications is limited. The small number of identified studies evaluating the association between genetic polymorphisms and peri-implant disease presented methodological and reporting inadequacies. Thus, the potential link between genetic polymorphisms and biological complications should be further investigated and clarified through well-designed clinical studies on adequately powered and appropriately included study populations.

Treatment of intrabony periodontal defects in controlled diabetic patients with an enamel matrix derivative: a split-mouth randomized clinical trial.

OBJECTIVE: This split-mouth randomized controlled trial aimed to evaluate the effect of enamel matrix derivative (EMD) associated with a simplified papilla preservation flap (SPPF) compared to SPPF alone in the surgical treatment of intrabony defects (ID) in type 2 diabetic mellitus (T2DM) patients. MATERIAL AND METHODS: Thirteen patients with controlled T2DM presenting with ID in at least two quadrants were included. In each patient, the test site (TS) was treated with SPPF plus EMD, whereas the control site (CS) was treated only with SPPF. Prior to surgery and at 6 months after intervention, the following parameters were evaluated: clinical attachment level (CAL), probing pocket depth (PPD), and gingival recession (GR). RESULTS: The TS and CS demonstrated a mean CAL gain of 3.31 ± 0.96 mm and 1.61 ± 1.12 mm, and a PPD reduction from 8.15 ± 0.98 to 3.00 ± 0.57 mm and 7.53 ± 0.96 to 4.69 ± 0.63 mm after 6 months, respectively. In both sites, the mean CAL gain and PPD reduction improved significantly after 6 months compared to baseline; however, the improvement was higher in the TS (p < 0.001). CONCLUSIONS: Both surgical procedures presented with clinical improvements in controlled T2DM patients. However, the additional use of EMD showed enhanced clinical results after 6 months with regard to CAL gain and PPD reduction. CLINICAL RELEVANCE: This study showed a better PPD reduction and CAL gain when an EMD was applied in addition to SPPF. Therefore, EMD may be used to enhance clinical outcomes in periodontal ID of controlled T2DM patients.

Molecular Biomarkers in Peri-Implant Health and Disease: A Cross-Sectional Pilot Study.

BACKGROUND: The aim of this feasibility study was to investigate the concentration level of CCL-20/MIP-3α, BAFF/BLyS, IL-23, RANKL, and Osteoprotegerin in the Peri-Implant Crevicular Fluid (PICF), from patients diagnosed with peri-implant mucositis and peri-implantitis, and to compare them with PICF from patients with healthy implants. METHODS: Participants with at least one dental implant with healthy peri-implant tissues, peri-implant mucositis, or peri-implantitis were included. PICF was collected using paper strips from healthy and diseased peri-implant sites (n = 19). Biomarker levels were analyzed using a custom Multiplex ELISA Assay Kit. RESULTS: In comparison to peri-implant health, the peri-implant mucositis group showed an increased concentration of CCL-20 MIP-3α, BAFF/BLyS, IL-23, RANKL, and Osteoprotegerin. The peri-implantitis group had the lowest median concentration of Osteoprotegerin (1963 ng/mL); this group had a similar concentration of RANKL (640.84 ng/mL) when compared to the peri-implant health group. BAFF/BLyS (17.06 ng/mL) showed the highest concentration in the peri-implantitis group. CONCLUSIONS: This feasibility study suggests that IL-23 and RANKL may help to elucidate the pathogenesis during the conversion from peri-implant health to peri-implantitis. Further research is required in BAFF/BLyS for the early diagnosis of peri-implantitis.

The Effect of Microcosm Biofilm Decontamination on Surface Topography, Chemistry, and Biocompatibility Dynamics of Implant Titanium Surfaces.

Since the inception of dental implants, a steadily increasing prevalence of peri-implantitis has been documented. Irrespective of the treatment protocol applied for the management of peri-implantitis, this biofilm-associated pathology, continues to be a clinical challenge yielding unpredictable and variable levels of resolution, and in some cases resulting in implant loss. This paper investigated the effect of microcosm biofilm in vitro decontamination on surface topography, wettability, chemistry, and biocompatibility, following decontamination protocols applied to previously infected implant titanium (Ti) surfaces, both micro-rough -Sandblasted, Large-grit, Acid-etched (SLA)-and smooth surfaces -Machined (M). Microcosm biofilms were grown on SLA and M Ti discs. These were treated with TiBrushes (TiB), combination of TiB and photodynamic therapy (PDT), combination of TiB and 0.2%CHX/1%NaClO, plus or minus Ultraviolet-C (UV-C) radiation. Surface topography was evaluated by Scanning Electron Microscopy (SEM) and Laser Surface Profilometry. Surface function was analysed through wettability analysis. Surface chemistry evaluation of the discs was performed under SEM/Energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Biocompatibility was tested with the cytocompatibility assay using human osteoblast-like osteosarcoma cell line (MG-63) cells. Elemental analysis of the discs disclosed chemical surface alterations resulting from the different treatment modalities. Titanium, carbon, oxygen, sodium, aluminium, silver, were identified by EDX as the main components of all the discs. Based on the data drawn from this study, we have shown that following the decontamination of Ti surfaces the biomaterial surface chemistry and topography was altered. The type of treatment and Ti surface had a significant effect on cytocompatibility (p = 0.0001). Although, no treatment modality hindered the titanium surface biocompatibility, parameters such as the use of chemical agents and micro-rough surfaces had a higher cytotoxic effect in MG-63 cells. The use of smooth surfaces, and photofunctionalisation of the TiO2 layer had a beneficial effect on cytocompatibility following decontamination.

The role of strontium ranelate and guided bone regeneration in osteoporotic and healthy conditions.

BACKGROUND/ OBJECTIVES: SR is a chemical agent developed for the treatment of osteoporosis. In vitro, SR enhanced replication of osteoprogenitor cells and bone formation. In vivo, in ovariectomized rats SR prevented the biomechanical deterioration of bone while in non-ovariectomized rats, enhanced bone architecture and increased trabecular and cortical bone mass. The aim of this study was to evaluate the effect of SR on bone healing of calvarial critical size defects treated with a deproteinized bovine bone mineral (DBBM) and a collagen barrier (CM), in healthy and osteoporotic rats. MATERIAL AND METHODS: Sixty-four, 4-month-old Wistar female rats were used. Osteoporosis was induced by ovariectomy and calcium-deficient diet in half of them. Sixteen ovariectomized (OSR) and 16 healthy (HSR) rats were treated with SR while no medication was administered in the remaining 16 healthy (H) and 16 ovariectomized (O) rats. At 6 weeks after ovariectomy, a 5mm defect was created in each parietal bone of every animal. One defect was treated with DBBM and CM, while the contralateral was left untreated. Qualitative and quantitative histological analysis was performed at 30 and 60 days of healing. A generalized estimating equations test was performed to evaluate the effect of SR and osteoporosis, on new bone formation (NB). RESULTS: After 30 days of healing, NB in the untreated defects was 3.4%±1.7%, 4.3%±6.2%, 3.2±4.5%, 15.9±23.5% in O, OSR, H and HSR groups, respectively; after 60 days, NB was 4.7%±4.3%, 11.3%±7%, 7.1%±13.2, 12.1%±13.5%, respectively. In the GBR-treated defects, after 30 days, NB was 2.6%±1.4%, 2.4%±1.6%, 4.5%±4.1%, 10.3%±14.4% in O, OSR, H and HSR groups, respectively; after 60 days, NB was 2.2%±1.6%, 4.3%±4.2%, 7%±5.1%, 10.8%±17.4%, respectively. Osteoporosis (p=0.008) and the absence of strontium ranelate treatment (p=0.01) had a negative impact on NB. CONCLUSION: SR may promote bone formation in calvarial defects in healthy and osteoporotic rats, albeit in a moderate extent.

The effect of a behavioural management tool in adults with mild to moderate periodontitis. A single-blind, randomized controlled trial.

OBJECTIVE: To compare a behavioural management program (test) to a standard communication approach (control) to reduce plaque, improve clinical outcomes and patient's compliance with oral self-care. BACKGROUND: Since psychological factors affect oral health-related behaviours, approaches directed at changing behaviours and improving compliance might improve the effect of oral health education. MATERIALS AND METHODS: This was a randomized, single-blind, parallel-design trial involving 71 patients with mild to moderate periodontitis. During a run-in period, all participants began using a power toothbrush. Two sessions of non-surgical periodontal therapy were performed post-baseline, along with one of the two oral healthcare communication approaches. Plaque and bleeding scores, probing pocket depth (PPD) and clinical attachment level (CAL) were recorded at the screening visit, baseline visit and at 8 and 14 weeks post-baseline. Patients were asked to fill in oral self-care diaries. Experience questionnaires were administered to both clinicians and patients to assess subjective experience of the clinician-patient interactions during the visits. RESULTS: In both groups, a significant reduction in plaque and bleeding scores was observed from baseline to 8 weeks after baseline, which then remained stable at week 14, but no differences between the groups were noted. An improvement in CAL and PPD was recorded at week 8 post-baseline in the test compared to the control group. No inter-group differences in the clinician's and subject's experience questionnaires were observed. CONCLUSION: Both approaches significantly promoted periodontal health. However, changing lifestyle requires repeated communication/engagement over time and a behavioural management program based upon two visits did not provide additional benefit compared to a standard approach.