Diagnostic value of VEGF in peri-implantitis and its correlation with titanium particles: A controlled clinical study.

OBJECTIVES: VEGF is prototypic marker of neovascularization, repeatedly proposed as intrinsic characteristic of peri-implantitis. This study aimed to assess pattern of VEGF in peri-implantitis, its correlation with titanium particles (TPs) and capacity as respective biomarker. MATERIAL AND METHODS: Pathological specificity of VEGF was assessed in peri-implant granulations using immunohistochemistry, periodontal granulations represented Ti-free positive controls. VEGF was correlated to TPs, identified using scanning electron microscopy coupled with dispersive x-ray spectrometry. Diagnostic accuracy, sensitivity and specificity of VEGF were estimated in PICF specimens from peri-implantitis, peri-implant mucositis (PIM) and healthy peri-implant tissues (HI) using machine learning algorithms. RESULTS: Peri-implantitis exhibited rich neovascular network with expressed density in contact zones toward neutrophil infiltrates without specific pattern variations around TPs, identified in all peri-implantitis specimens (mean particle size 8.9 ± 24.8 µm2; Ti-mass (%) 0.380 ± 0.163). VEGF was significantly more expressed in peri-implantitis (47,065 ± 24.2) compared to periodontitis (31,14 ± 9.15), and positively correlated with its soluble concentrations in PICF (p = 0.01). VEGF was positively correlated to all clinical endpoints and significantly increased in peri-implantitis compared to both PIM and HI, but despite high specificity (96%), its overall diagnostic capacity was average. Two patient clusters were identified in peri-implantitis, one with 8-fold higher VEGF values compared to HI, and second with lower values comparable to PIM. SIGNIFICANCE: VEGF accurately reflects neovascularization in peri-implantitis that was expressed in contact zones toward implant surface without specific histopathological patter variation around TPs. VEGF answered requests for biomarker of peri-implantitis but further research is necessary to decrypt its exact underlying cause.

Effect of argon plasma abutment activation on soft tissue healing: RCT with histological assessment.

OBJECTIVE: To assess the peri-implant soft tissue profiles between argon plasma treatment (PT) and non-treated (NPT) healing abutments by comparing clinical and histological parameters 2 months following abutment placement. MATERIALS AND METHODS: Thirty participants were randomly assigned to argon-plasma treatment abutments group (PT) or non-treated abutments (NPT) group. Two months after healing abutment placement, soft peri-implant tissues and abutment were harvested, and histological and clinical parameters including plaque index, bleeding on probing, and keratinized mucosa diameter (KM) were assessed. Specialized stainings (hematoxylin-eosin and picrocirious red) coupled with immunohistochemistry (vimentin, collagen, and CK10) were performed to assess soft tissue inflammation and healing, and the collagen content keratinization. In addition to standard statistical methods, machine learning algorithms were applied for advanced soft tissue profiling between the test and control groups. RESULTS: PT group showed lower plaque accumulation and inflammation grade (6.71% vs. 13.25%, respectively; p-value 0.02), and more advanced connective tissue healing and integration compared to NPT (31.77% vs. 23.3%, respectively; p = 0.009). In the control group, more expressed keratinization was found compared to the PT group, showing significantly higher CK10 (>47.5%). No differences in KM were found between the groups. SIGNIFICANCE: PT seems to be a promising protocol for guided peri-implant soft tissue morphogenesis reducing plaque accumulation and inflammation, and stimulating collagen and soft tissue but without effects on epithelial tissues and keratinization.

Resolution of peri-implant mucositis following standard treatment: A prospective split-mouth study.

BACKGROUND: Peri-implant mucositis (PIM) is a pathological precursor of peri-implantitis, but its pattern of conversion to peri-implantitis is unclear and complicated to diagnose clinically, while none of the available protocols yield complete disease resolution. The aim of this study was the evaluation of PIM responsiveness to standard anti-infective mechanical treatment (AIMT) at clinical and biomarker levels, and estimation of the diagnostic capacity of bone markers as surrogate endpoints and predictors. METHODS: Systemically healthy outpatients presenting one implant exhibiting clinical signs of inflammation confined within the soft tissue (PIM) and one healthy control (HC) implant at a non-adjacent position were included. Clinical parameters and peri-implant crevicular fluid samples were collected baseline and 6 months following mechanical therapy, to assess the levels of RANKL, OPG, and IGFBP2. PIM clustering was performed using machine learning algorithms. RESULTS: Overall, 38 patients met the inclusion criteria. Therapy resulted in the reduction of all clinical and biological indicators, but respective values remained significantly higher compared to HC. Clinical examination noted 30% disease resolution at the 6-month follow-up, while 43% showed no active bone resorption. OPG showed positive prognostic value for treatment outcome, while the clustering based on active bone resorption did not differ in terms of therapeutic effectiveness. CONCLUSION: AIMT is effective in reducing the clinical and biological indicators of PIM, but complete clinical resolution was achieved in only 30% of the cases. Around one third of PIM patients exhibited active bone resorption bellow clinical detectability that was not associated with disease progression and poor treatment responsiveness.

Effect of argon plasma pre-treatment of healing abutments on peri-implant microbiome and soft tissue integration: a proof-of-concept randomized study.

PURPOSE: Biofilm-free implant surface is ultimate prerequisite for successful soft and bone tissue integration. Objective of the study was to estimate the effects of argon plasma healing abutment pre-treatment (PT) on peri-implant soft-tissue phenotype (PiSP), inflammation, plaque accumulation and the microbiome (PiM) between non-treated (NPT) and treated (PT) abutments following 3-months healing period. The hypothesis was that cell-conductive and antimicrobial properties of PT would yield optimal conditions for soft tissue integration. MATERIAL AND METHODS: Two months following second-phase surgery, microbiological and clinical parameters were assessed around thirty-six healing abutments with two types of microtopography, smooth surface (MACHINED) and ultrathin threaded microsurface (ROUGH). A two level randomization schema was used to achieve equal distribution and abutments were randomly divided into rough and machined groups, and then divided into PT and NPT groups. PiM was assessed using next-generation DNA sequencing. RESULTS: PiM bacterial composition was highly diverse already two months post-implantation, consisting of key-stone pathogens, early and late colonizers, while the mycobiome was less diverse. PT was associated with lower plaque accumulation and inflammation without significant impact on PiSP, while in NPT clinical parameters were increased and associated with periopathogens. NPT mostly harbored late colonizers, while PT exerted higher abundance of early colonizers suggesting less advanced plaque formation. Interaction analysis in PT demonstrated S. mitis co-occurrence with pro-healthy Rothia dentocariosa and co-exclusion with Parvimonas micra, Porphyromonas endodontalis and Prevotella oris. PiSP parameters were generally similar between the groups, but significant association between PiM and keratinized mucosa width was observed in both groups, with remarkably more expressed diversity in NPT compared to PT. PT resulted in significantly lower BOP and PI around rough and machined abutments, respectively, without specific effect on PiM and PiSP. CONCLUSIONS: PT contributed to significantly the less advanced biofilm accumulation and inflammation without specific effects on PiSP.

Study on the immunopathological effect of titanium particles in peri-implantitis granulation tissue: A case-control study.

OBJECTIVES: To identify titanium particles (TPs) in biopsy specimens harvested from peri-implantitis lesions and secondarily to study the histopathological characteristics in peri-implantitis compared to periodontitis, in order to evaluate whether the presence of TPs could alter respective inflammatory patterns. MATERIAL AND METHODS: Biopsies containing granulation tissue were harvested during routine surgical treatment in 39 peri-implantitis cases and 35 periodontitis controls. Serial sections were obtained using titanium-free microtome blades. The first and last sections of the peri-implantitis specimens were used for identification of TPs by scanning electron microscopy coupled with dispersive X-ray spectrometry. Intermediate sections and periodontitis specimens were processed for descriptive histological study using haematoxylin-eosin staining and for immunohistochemical analysis using CD68, IL-6, Nf-kB and VEGF markers. RESULTS: TPs were identified in all peri-implantitis specimens as free metal bodies interspersed within granulation tissue. However, presence of macrophages or multinucleated giant cells engulfing the TPs were not identified in any specimen. Peri-implantitis granulations were characterized by a chronic inflammatory infiltrate rich in neutrophils. About half of peri-implantitis patients exhibited a subacute infiltrate characterized with lymphocytes interweaved with neutrophils and eosinophils. When compared to periodontitis, peri-implantitis tissues showed higher proportions of macrophages and a more intense neovascularization, based on significantly higher expression of CD68 and VEGF respectively. CONCLUSION: TPs were identified in all peri-implantitis specimens, but without evidencing any foreign body reaction suggestive for direct pathological effects of TPs. The peri-implantitis granulation tissue was characterized by intense neovascularization and presence of a chronic inflammatory infiltrate dominated by plasma cells, neutrophils and macrophages.

Underdiagnosis in Background of Emerging Public Health Challenges Related to Peri-Implant Diseases: An Interventional Split-Mouth Study.

Peri-implant diseases are an emerging public health problem, and it's considered that limitations of standard diagnostics play the role herein. The study objective was the estimation of pathological bone resorption at clinical and biological level in patients with peri-implant mucositis (PIM) and peri-implantitis (PI) before and 6 months after standard treatment and to compare them with healthy controls (HC). The split-mouth interventional study included 60 patients affected with PIM or PI. Patients that also presented at least one more HC were enrolled in the study and underwent standard non-surgical and surgical treatment, respectively. Standard clinical parameters and soluble levels of RANKL were measured in peri-implant crevicular fluid baseline and 6 months following treatment. Clinical parameters and RANKL significantly decreased following treatment in PIM and PI. However, bleeding on probing and probing depth remained significantly increased when compared to HC. RANKL answered requests for biomarker of peri-implant diseases, its baseline levels were significantly increased in PIM and PI, they decreased following treatment and reached HC in peri-implantitis, while in PIM RANKL remained significantly increased. Presence of pathological bone resorption in patients lacked its clinical signs, and respective persistence following treatment suggest the need for biomarker-supported diagnosis for timely diagnosis of peri-implantitis and appropriate orientation of respective management strategies.

Diagnostic Accuracy of Cone Beam Computed Tomography in Identifying Peri-implantitis-Like Bone Defects Ex Vivo.

This pilot study aimed to assess the diagnostic accuracy of CBCT in identifying peri-implantitis-like bone defects in cadavers. Three cadaver dental arches treated with the Thiel embalming method were used. Three different types of peri-implant bone defects (buccal dehiscence, two- to three-wall defects, and circumferential defects) were prepared on 15 implants. Defect depths and lengths were identified clinically using a periodontal probe, radiologically by means of CBCT images, and histologically with a micrometer using an optic microscope. Peri-implant bone defect morphology evaluated using CBCT images matched the clinical defect configuration (100% accuracy). CBCT assessment demonstrated lower values in defect depth and defect length when compared with the clinical evaluation. A statistically significant difference in defect depth (0.35 ± 0.45 mm; P = .037) was recorded between the clinical and CBCT data. Regarding defect length, a statistically significant mean difference of 0.81 ± 0.83 mm (P = .003) was noted between the clinical and CBCT data. Similarly, a mean difference of 1.09 ± 1.52 mm was recorded between the defect length assessed histologically and the CBCT data (P = .031). No statistically significant differences were observed between the other evaluated variables. CBCT is a reliable tool for peri-implantitis diagnosis and treatment planning, though the underestimation of defect severity may affect the prognosis and clinical decision-making. Clinicians need to be flexible in establishing prognoses and treatment based on CBCT assessment.

Estimating the Effects of Dental Caries and Its Restorative Treatment on Periodontal Inflammatory and Oxidative Status: A Short Controlled Longitudinal Study.

Dental caries and periodontitis are among the most common health conditions that are currently recognized as growing socio-economic problems relating to their increasing prevalence, negative socio-economic impact, and harmful effects on systemic health. So far, the exact effects of caries and standard restorative materials on periodontal inflammatory and oxidative status are not established. The present study aimed to investigate the effect of caries and its restoration using standard temporary and permanent filling materials on a panel of 16 inflammatory and oxidative markers in gingival crevicular fluid (GCF) of periodontally healthy individuals, 7 (D7) and 30 (D30) days post-restoration, while the intact teeth represented the control. One hundred ninety systemically and periodontally healthy patients with occlusal caries underwent standard cavity preparation and restorations with one of six standard temporary or permanent restorative material according to indication and randomization scheme. Interleukin (IL)-2, IFN- γ, IL-12, IL-17A, IL-13, IL-9, IL-10, IL-6, IL-5, IL-4, IL-22, TNF-α, IL1- ß, thiobarbituric acid reactive substances, superoxide dismutase, and reduced form of glutathione were measured in GCF samples by flowcytometry and spectrophotometry in aid of commercial diagnostic assays. Caries affected teeth exhibited significantly increased IL-1 ß, IL-17, IL-22, and TBARS and decreased IL-9 concentrations compared to healthy controls. Treatment generally resulted in an increased antioxidant capacity with exception of zinc-polycarboxylate cement showing distinctive inflammatory pattern. Comparison of inflammatory and oxidative profiles in temporary and permanent restorations showed material-specific patterning which was particularly expressed in temporary materials plausibly related to greater caries extension. Caries affected teeth exhibited a balanced inflammatory pattern in GCF, with a general tendency of homeostatic re-establishment following treatment. Restorative materials did not provide specific pathological effects, although some material groups did exhibit significantly elevated levels of inflammatory and oxidative markers compared to healthy controls, while the material-specific patterning was observed as well.

A Roadmap towards Precision Periodontics.

Periodontitis is among the most common health conditions and represents a major public health issue related to increasing prevalence and seriously negative socioeconomic impacts. Periodontitis-associated low-grade systemic inflammation and its pathological interplay with systemic conditions additionally raises awareness on the necessity for highly performant strategies for the prevention and management of periodontitis. Periodontal diagnosis is the backbone of a successful periodontal strategy, since prevention and treatment plans depend on the accuracy and precision of the respective diagnostics. Periodontal diagnostics is still founded on clinical and radiological parameters that provide limited therapeutic guidance due to the multifactorial complexity of periodontal pathology, which is why biomarkers have been introduced for the first time in the new classification of periodontal and peri-implant conditions as a first step towards precision periodontics. Since the driving forces of precision medicine are represented by biomarkers and machine learning algorithms, with the lack of periodontal markers validated for diagnostic use, the implementation of a precision medicine approach in periodontology remains in the very initial stage. This narrative review elaborates the unmet diagnostic needs in periodontal diagnostics, the concept of precision periodontics, periodontal biomarkers, and a roadmap toward the implementation of a precision medicine approach in periodontal practice.

Titanium abutment surface modifications and peri-implant tissue behavior: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the effect of various titanium abutment modifications on the behaviour of peri-implant soft tissue healing, inflammation and maintenance. MATERIAL AND METHODS: An electronic database research until 30 April 2019 was performed. A meta-analysis (MA) for each outcome parameter was performed by using the random-effects models with the DerSimonian-Laird estimator. RESULTS: Ten studies were included in the present review. Four studies with a long follow-up (5-6 years) reported the outcomes in a heterogeneous way and were suitable for MA. Six studies (4 RCT, 2 CCT) including 118 patients and 182 implants dealing with a modified healing abutment surface and short follow-up were selected for MA. The MA for PI and BoP as outcome showed no significant differences between surfaces (PI: P = 0.091; BoP: P = 0.099). The MA for PD as outcome showed no significant differences between surfaces (P = 0.488). No statistical significance was found by evaluating each mixed-effects model for potential moderators (type of study, study design, number of implants, follow-up length). The other four studies with a longer follow-up (5-6 years) reported contradictory results depending on the surface treatment investigated. CONCLUSIONS: Within their limits, the present findings suggest that peri-implant soft tissue may not be affected by the surface treatment of titanium abutments on the short term. Contrasting results are reported in longer follow-up periods depending on the technique used to modify the abutment. CLINICAL RELEVANCE: Clinicians should carefully evaluate the use of a modified titanium surface in their practice. Even if no differences in terms of inflammation are present at short term, these findings need to be validated in long-term studies.

Effects of argon plasma treatment on the osteoconductivity of bone grafting materials.

BACKGROUND: The osteoconductive properties of bone grafting materials represent one area of research for the management of bony defects found in the fields of periodontology and oral surgery. From a physico-chemical aspect, the wettability of the graft has been demonstrated to be one of the most important factors for new bone formation. It is also well-known that argon plasma treatment (PAT) and ultraviolet irradiation (UV) may increase the surface wettability and, consequently, improve the regenerative potential of the bone grafts. Therefore, the aim of the present in vitro study was to evaluate the effect of PAT and UV treatment on the osteoconductive potential of various bone grafts. MATERIALS AND METHODS: The following four frequently used bone grafts were selected for this study: synthetic hydroxyapatite (Mg-HA), biphasic calcium phosphate (BCP), cancellous and cortical xenogenic bone matrices (CaBM, CoBM). Sixty-six serially numbered disks 10 mm in diameter were used for each graft material and randomly assigned to the following three groups: test 1 (PAT), test 2 (UV), and control (no treatment). Six samples underwent topographic analysis using SEM pre- and post-treatments to evaluate changes in surface topography/characteristics. Additionally, cell adhesion and cell proliferation were evaluated at 2 and 72 h respectively following incubation in a three-dimensional culture system utilizing a bioreactor. Furthermore, the effects of PAT and UV on immune cells were assessed by measuring the viability of human macrophages at 24 h. RESULTS: The topographic analysis showed different initial morphologies of the commercial biomaterials (e.g., Mg-HA and BCP showed flat morphology; BM samples were extremely porous with high roughness). The surface analysis following experimental treatments did not demonstrate topographical difference when compared with controls. Investigation of cells demonstrated that PAT treatment significantly increased cell adhesion of all 4 evaluated bone substitutes, whereas UV failed to show any statistically significant differences. The viability test revealed no differences in terms of macrophage adhesion on any of the tested surfaces. CONCLUSION: Within their limitations, the present results suggest that treatment of various bone grafting materials with PAT appears to enhance the osteoconductivity of bone substitutes in the early stage by improving osteoblast adhesion without concomitantly affecting macrophage viability. CLINICAL RELEVANCE: Treatment of bone grafts with PAT appears to result in faster osseointegration of the bone grafting materials and may thus favorably influence bone regeneration.

Effect of dental caries on periodontal inflammatory status: A split-mouth study.

OBJECTIVE: This controlled split-mouth study aimed to estimate the effect of caries and related treatment on concentrations of interleukin (IL)-2, interferon (IFN)-γ, IL-12, IL-17A, IL-13, IL-10, IL-6, IL-5, IL-4, IL-22, tumor necrosis factor (TNF)-α, and IL1-ß in gingival crevicular fluid (GCF) of caries affected teeth before (B), 7 (7D) and 30 (30D) days post-treatment and to compare them with concentrations from healthy teeth. DESIGN: Study population included 81 systemically and periodontally healthy non-smokers exhibiting at least one shallow occlusal/ inter-proximal caries and one healthy tooth from the same morphologic group at the contralateral position. Following clinical exam, the GCF samples were collected baseline as well as 7D and 30D, while the biomarker measurement was performed using multiplex flowcytometry. RESULTS: Caries affected teeth exhibited significantly higher levels of IFN-γ, IL-1ß, IL-2, IL-4 and IL-6 when compared to healthy teeth. Post-treatment cytokines levels showed general trend of increase when compared to baseline, that was significant for IL-22 and IL-17 at 7D, while IFN-γ was significantly increased at 7D compared to the healthy teeth. At 30D, IFN-γ, TNF-α, IL-17 and IL-4 levels were significantly increased when compared to healthy teeth, while IL-2 levels were significantly higher than baseline levels. CONCLUSION: Considering significantly increased periodontal levels of inflammatory markers in caries affected teeth and in response to performed treatment, it seems that dental caries and related restorative treatment might contribute to periodontal inflammation via additive effects already in early-stage caries.

Is the personalized approach the key to improve clinical diagnosis of peri-implant conditions? The role of bone markers.

BACKGROUND: Study objectives were 1) to estimate diagnostic capacity of clinical parameters, receptor activator of nuclear factor kappa-B (RANKL) and osteoprotegerin (OPG) to diagnose healthy peri-implant condition (HI), peri-implant mucositis (PIM) and peri-implantitis (PIMP) by assessing respective diagnostic accuracy, sensitivity, specificity and diagnostic ranges 2) to develop personalized diagnostic model (PDM) for implant monitoring. METHODS: Split-mouth study included 126 patients and 252 implants (HI = 126, PIM = 57, and PIMP = 69). RANKL and OPG concentrations were estimated in peri-implant crevicular fluid using enzyme-linked immunosorbent assay method and assessed with clinical parameters using routine statistics, while the diagnostic capacity of individual parameters and overall clinical diagnosis were estimated using classifying algorithms. PDM was developed using decision trees. RESULTS: Bleeding on probing (BOP), plaque index, and probing depth (PD) were confirmed reliable discriminants between peri-implant health and disease, while increase in PD (PD > 4 mm) and suppuration were good discriminants amongst PIM/PIMP. Bone turnover markers (BTMs) demonstrated presence of bone resorption in PIM; between comparable diagnostic ranges PIM/PIMP, PIMP was clinically distinguished from PIM in about 60% of patients while 40% remained diagnosed as false negatives. PDM demonstrated highest diagnostic capacity (accuracy: 96.27%, sensitivity: 95.00%, specificity: 100%) and defined HI: BOP ≤0.25%; PIM: BOP >0.25%, PD ≤4.5 mm; PIMP: BOP >0.25%, PD >4.5 mm and RANKL ≤19.9 pg/site; PIM: BOP >0.25%, PD >4.5 mm, and RANKL >19.9 pg/site. CONCLUSIONS: BTMs demonstrated capacity to substantially improve clinical diagnosis of peri-implant conditions. Considering lack of difference in BTMs between PIM/PIMP and cluster of PIM with exceeding BTMs, a more refined definition of peri-implant conditions according to biological characteristics is required for further BTMs validation and appropriate PIMP management.

Periodontal regenerative medicine using mesenchymal stem cells and biomaterials: A systematic review of pre-clinical studies.

The aim of the systematic review was to analyze the use of mesenchymal stem cells (MSC) and biomaterial for periodontal regeneration from preclinical animal models and human. Electronic databases were searched and additional hand-search in leading journals was performed. The research strategy was achieved according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The including criteria were as follows: MSC, biomaterial, in vivo studies, with histologic and radiologic analysis and written in English. The risk of bias was assessed for individual studies. A total of 50 articles were selected and investigated in the systematic review. These results indicate that MSC and scaffold provide beneficial effects on periodontal regeneration, with no adverse effects of such interventions. Future studies need to identify the suitable association of MSC and biomaterial and to characterize the type of new cementum and the organization of the periodontal ligament fiber regeneration.

Estimation of the diagnostic accuracy of clinical parameters for monitoring peri-implantitis progression: An experimental canine study.

BACKGROUND: Lack of consensus on the clinical parameters of peri-implantitis may complicate accurate diagnosis of the disorder. Furthermore, the lack of reliable estimates of the diagnostic capacity of the clinical endpoints precludes the definition of an effective treatment protocol for peri-implantitis. The present canine study assesses the diagnostic accuracy of the clinical parameters for monitoring the peri-implant tissues in a controlled ligature-induced peri-implantitis model followed by a spontaneous progression phase. METHODS: Six beagle dogs were followed-up on during three episodes of ligature-induced peri-implantitis and a further episode of spontaneous progression. Probing depth (PD), bleeding on probing (BOP), mucosal recession (MR), and suppuration (SUP) were recorded at four sites per implant and at four study timepoints. Moreover, the implant mucosal index (IMI) was calculated at implant level. Marginal bone loss (MBL) was determined using computed tomography at four sites per implant. A linear regression model was used to estimate clinical and radiological parameters during peri-implantitis progression. RESULTS: Progressive peri-implant bone loss is characterized by an increase in PD, more profuse BOP, MR, and SUP in advanced cases (p < 0.001). However, even in the presence of severe bone loss, SUP was not a common finding, with an incidence of approximately 10% at the last timepoint. These clinical parameters were significantly correlated to MBL at most of the timepoints. The IMI, in turn, showed a positive correlation to MBL and the peri-implant inflammatory signs (r = 0.39; p < 0.001), with a tendency to exhibit higher scores during ligature-induced peri-implantitis, followed by a slight decrease during the spontaneous progression period. CONCLUSION: The clinical features of peri-implantitis and spontaneous progression of the disorder may facilitate an accurate monitoring of peri-implant pathologic bone loss.

Evaluation of a hydrogel membrane on bone regeneration in furcation periodontal defects in dogs.

The aim of the study was to evaluate bone regeneration using a canine model with surgically created periodontal defects filled for 12 weeks using a stratified biomaterial consisting in a biphasic calcium phosphate (BCP) covered with a crosslinking hydrogel acting as polymer membrane of silated hydroxypropyl methylcellulose (Si-HPMC) as the tested new concept. Bilateral, critical-sized, defects were surgically created at the mandibular premolar teeth of six adult beagle dogs. The defects were randomly allocated and: (i) left empty for spontaneous healing or filled with: (ii) BCP and a collagen membrane; (iii) BCP and hydrogel Si-HPMC membrane. At 12 weeks, the experimental conditions resulted in significantly enhanced bone regeneration in the test BCP/Si-HPMC group. Within the limits of this study, we suggest that the hydrogel Si-HPMC may act as an occlusive barrier to protect bone area from soft connective tissue invasion and then effectively contribute to enhance bone regeneration.

Diagnostic accuracy of clinical parameters to monitor peri-implant conditions: A matched case-control study.

BACKGROUND: The aim of this case-control study was to estimate the diagnostic accuracy of the standard clinical parameters in diagnosing healthy peri-implant tissues, peri-implant mucositis, and peri-implantitis. METHODS: A case-control study was designed to compare the clinical parameters used in the diagnosis of peri-implant diseases such as: probingdepth (PD), bleeding on probing (BOP), mucosal redness (MR), suppuration (SUP), and plaque index (PI). Furthermore, the influence of patient- (sex, age) and implant-related variables (implant neck configuration, time in function after loading) were evaluated to investigate the association with the clinical findings. The inferential analysis consisted of estimation by generalized estimating equations (GEE) of multilevel logistic regression models. RESULTS: In total, 1,572 sites were evaluated around 262 implants from 141 patients. Sites with implant mucositis showed significant levels of BOP (OR = 3.56), MR (OR = 7.66) and PD (OR = 1.48) compared to healthy sites. The specificity was 90.3% while the sensitivity was only 43.6%. Likewise, sites exhibiting peri-implantitis showed significant levels of BOP (OR = 2.32), MR (OR = 7.21), PD (OR = 2.43) and SUP (OR = 6.81) compared to healthy sites. Again, the multiple logistic regressions showed high specificity (92.1%) but modest sensitivity (52.5%). PD was the only diagnostic marker displaying significance comparing peri-implant mucositis and peri-implantitis sites (OR = 1.76). Moreover, tissue-level compared to bone-level implants were less associated with SUP+ (OR = 0.20), and PI (OR = 0.36) and demonstrated statistical significance. In addition, age, sex, and function time significantly influenced the tested clinical parameters. CONCLUSIONS: The diagnosis of peri-implant diseases cannot rely solely upon individual clinical parameters but rather require a combination of criteria. The clinical parameters, particularly probing depth, might accurately discern between diagnoses among peri-implant conditions. Nevertheless, the specificity of the clinical parameters surpasses the sensitivity in the detection of peri-implant diseases, validating its potential use as a diagnostic tool.

What is the Impact of Epstein-Barr Virus in Peri-implant Infection?

PURPOSE: To compare the qualitative and quantitative profile of Epstein-Barr virus (EBV) at external and internal implant surfaces between participants with peri-implantitis and healthy peri-implant tissues and to quantitatively assess the relation between EBV and periopathogens inside the microbiologic profile associated with peri-implantitis. MATERIALS AND METHODS: Microbiologic specimens were retrieved from 84 patients wearing 190 implants to estimate the levels of EBV and 10 periopathogens in the peri-implant pocket and internal-implant connection using quantitative polymerase chain reaction. RESULTS: The study sample consisted of 113 healthy and 77 peri-implantitis-affected implants. Statistical significance was not reached in EBV prevalence between peri-implantitis and healthy controls. EBV-positive participants demonstrated higher levels of Prevotella intermedia (Pi) and Campylobacter rectus (Cr) compared with EBV-negative participants. A positive correlation was demonstrated among EBV and Tannerella forsythia (Tf), Parvimonas micra (Pm), Fusobacterium nucleatum (Fn), and Cr levels in peri-implantitis-affected implants, while healthy controls demonstrated a positive correlation between EBV and Aggregatibacter actinomycetemcomitans (Aa), Pi, and Pm. CONCLUSION: EBV cannot be considered as a microbiologic marker of peri-implantitis. However, EBV could be considered as a risk factor and a peri-implantitis enhancer based on its positive correlations with pathogens associated with peri-implantitis.

How frequent does peri-implantitis occur? A systematic review and meta-analysis.

OBJECTIVES: The objective of this study is to estimate the overall prevalence of peri-implantitis (PI) and the effect of different study designs, function times, and implant surfaces on prevalence rate reported by the studies adhering to the case definition of Sanz & Chapple 2012. MATERIAL AND METHODS: Following electronic and manual searches of the literature published up to February 2016, data were extracted from the studies fitting the study criteria. Meta-analysis was performed for estimation of overall prevalence of PI while the effects of the study design, function time, and implant surface type on prevalence rate were investigated using meta-regression method. RESULTS: Twenty-nine articles were included in this study. The prevalence rate in all subset meta-analyses was always higher at patient level when compared to the prevalence rate at the implant level. Prevalence of PI was 18.5% at the patient level and 12.8% at the implant level. Meta-regression analysis did not identify any association for different study designs and function times while it was demonstrated the significant association between moderately rough surfaces with lower prevalence rate of PI (p = 0.011). CONCLUSIONS: The prevalence rate of PI remains highly variable even following restriction to the clinical case definition and it seems to be affected by local factors such as implant surface characteristics. The identification of adjuvant diagnostic markers seems necessary for more accurate disease classification. CLINICAL RELEVANCE: The occurrence of PI is affected by local factors such as implant surface characteristics hence the careful assessment of the local factors should be performed within treatment planning.

The predictive value of microbiological findings on teeth, internal and external implant portions in clinical decision making.

AIM: The primary aim of this study was to evaluate 23 pathogens associated with peri-implantitis at inner part of implant connections, in peri-implant and periodontal pockets between patients suffering peri-implantitis and participants with healthy peri-implant tissues; the secondary aim was to estimate the predictive value of microbiological profile in patients wearing dental implants using data mining methods. MATERIAL AND METHODS: Fifty participants included in the present case─control study were scheduled for collection of plaque samples from the peri-implant pockets, internal connection, and periodontal pocket. Real-time polymerase chain reaction was performed to quantify 23 pathogens. Three predictive models were developed using C4.5 decision trees to estimate the predictive value of microbiological profile between three experimental sites. RESULTS: The final sample included 47 patients (22 healthy controls and 25 diseased cases), 90 implants (43 with healthy peri-implant tissues and 47 affected by peri-implantitis). Total and mean pathogen counts at inner portions of the implant connection, in peri-implant and periodontal pockets were generally increased in peri-implantitis patients when compared to healthy controls. The inner portion of the implant connection, the periodontal pocket and peri-implant pocket, respectively, presented a predictive value of microbiologic profile of 82.78%, 94.31%, and 97.5% of accuracy. CONCLUSION: This study showed that microbiological profile at all three experimental sites is differently characterized between patients suffering peri-implantitis and healthy controls. Data mining analysis identified Parvimonas micra as a highly accurate predictor of peri-implantitis when present in peri-implant pocket while this method generally seems to be promising for diagnosis of such complex infections.