New insights on collagen structural organization and spatial distribution around dental implants: a comparison between machined and laser-treated surfaces.

BACKGROUND: One of the main factors for the osseointegration of dental implants is the development of an adequate soft tissue barrier, mainly composed by collagen, which protects the implant from bacterial development. The structural features of the peri-implant collagen are influenced by the implant components and, in particular, by the type of the surface. In the clinical practice, healing abutments are characterized by smooth surfaces, named machined. Recently, a new laser technique, Synthegra, has been developed to obtain a topography-controlled surface with micrometric regular pores that seems reducing the risk of peri-implantitis. Based on this background, this study aims investigating the structural organization and spatial distribution of collagen surrounding healing abutments characterized by laser-treated and machined surfaces. METHODS: Gingiva portions surrounding custom-made healing abutments (HA), characterized by alternated laser-treated and machined surfaces, were collected and analyzed by combining Fourier Transform InfraRed Imaging (FTIRI) spectroscopy, a non-invasive and high-resolution bidimensional analytical technique, with histological and multivariate analyses. RESULTS: Masson's trichrome staining, specific for collagen, highlighted a massive presence of collagen in all the analyzed samples, evidencing a surface-related spatial distribution. The nature of collagen, investigated by the FTIRI spectroscopy, appeared more abundant close to the laser-treated surface, with a perpendicular disposition of the bundles respect to the HA; conversely, a parallel distribution was observed around the machined surface. A different secondary structure was also found, with a higher amount of triple helices and a lower quantity of random coils in collagen close to the laser treated surfaces. CONCLUSIONS: FTIRI spectroscopy demonstrates that the use of a laser treated transmucosal surface can improve the morphological organization of the peri-implant collagen, which presents a distribution more similar to that of natural teeth. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT05754970). Registered 06/03/2023, retrospectively registered, https://clinicaltrials.gov/show/NCT05754970 .

Effect of temperature on presepsin pre-analytical stability in biological fluids of preterm and term newborns.

OBJECTIVES: Thermostability is one of the pre-requisites for the reliability of analytes in clinical practice and biomedical research. Although presepsin represents a promising new biomarker for the early diagnosis of sepsis in newborns, data on its stability under different storage conditions are lacking. We aimed to investigate presepsin thermostability in blood, urine and saliva samples after thawing at 4 predetermined monitoring time-points in a cohort of preterm and term infants. METHODS: We conducted an observational study, where each case served as its own control, in 24 preterm and term infants. Blood, urine and saliva samples were stored at -80 °C for 18 months, and presepsin measured in different biological fluids at thawing (T0), 24 (T1), 48 (T2) and at 72 (T3) hours after thawing. RESULTS: No significant differences (p>0.05, for all) in presepsin levels were observed at T0-T3 in the different biological fluids. Furthermore, no differences at T0-T3 were observed in presepsin levels between blood and saliva fluids, whilst urine levels were significantly higher (p<0.05, for all) than blood and saliva at T0-T3. CONCLUSIONS: Results on presepsin pre-analytical thermo-stability in different biological fluids after long-term refrigeration support the reliability of this biomarker in the diagnosis and monitoring of perinatal sepsis.

A systematic review on removal of osseointegrated implants: un update.

BACKGROUND: Today dental implants represent an effective therapy in case of partial or total edentulism, with an excellent success rate. Despite the results obtained, there may be biological or mechanical complications during the therapy, which lead to the loss of the implant. This systematic review aims to evaluate the current state of the art in the literature on techniques used for the removal of dental implants. Various aspects will be analyzed, such as the success of the technique, any complications, and the advantages and disadvantages of their use. METHODS: Two reviewers conducted a literature analysis (PubMed, Embase, Web of Science) of the last 20 years (2003-2023). The main criterion analyzed was the success of the technique, while secondary outcomes such as complications and risks of the technique were also analyzed. 258 articles were identified in the various search databases. 42 eligible articles were subsequently identified after an article screening. Only 18 full texts were subsequently included in the review. RESULTS: A total of 18 articles were selected and 1142 implants and 595 patients were included. The main techniques used were the Counter-Torque Ratchet Technique (CTRT), Piezoelectric bone surgery (PBS), trephine drills, carbide burs, Erbium, Chromium, Yttrium, Scandium, Gallium, Garnett (Er:Cr:YSGG) laser and carbon dioxide (CO2) laser. Combined uses of techniques have been identified such as: PBS and trephine burs or carbide burs, trephine burs with the use of a 3d-printed guide, CTRT and trephine burs. The technique with the highest success rate, less morbidity for the patient, and less removal of bone appears to be the CTRT. CONCLUSIONS: The use of conservative techniques, especially CTRT, in bone removal is useful to allow for immediate implant placement in the removal area. However, further studies with a high sample size are needed to be performed on all techniques, particularly new randomized controlled trials (RCTs) that allow for the analysis of the success of alternative techniques such as Laser and Piezosurgery, which appear to be very promising.

Impact on peri-implant connective tissue of laser treated versus traditional healing abutments: a human clinical trials.

BACKGROUND: Dental implant is the principal treatment for edentulism and the healthiness of the peri-implant tissue has a pivotal role for its longterm success. In addition, it has been shown that also the topography of the healing abutment can influence the outcome of the restoration. The objective of this human clinical trial was to assess the impact of a novel laser-treated healing abutment on peri-implant connective tissue and extracellular matrix proteins compared to the conventional machined surface, which served as the control group. METHODS: During second surgical stage a customized healing abutment were inserted on 30 single dental implants. Healing abutments were realized with two alternated different surface (two side laser-treated surfaces and two side machined surfaces) in order to be considered both as test and control on the same implant and reduce positioning bias. Following the soft tissue healing period (30 ± 7 days) a 5 mm circular biopsy was retrieved. Immuno-histochemical and quantitative real-time PCR (qPCR) analyses were performed on Collagen, Tenascin C, Fibrillin I, Metalloproteinases (MMPs) and their inhibitor (TIMPs). 15 were processed for qPCR, while the other 15 were processed for immunohistochemical analysis. Paired t-test between the two groups were performed. A value of p < 0.05 was considered statistically significant. RESULTS: Results revealed that the connective tissue facing the laser-treated surface expressed statistically significant lower amount of MMPs (p < 0.05) and higher level of TIMPs 3 (p < 0.05), compared to the tissue surrounding the machined implant, which, in turn expressed also altered level of extracellular matrix protein (Tenascin C, Fibrillin I (p < 0.05)) and Collagen V, that are known to be altered also in peri-implantitis. CONCLUSIONS: In conclusion, the laser-treated surface holds promise in positively influencing wound healing of peri-implant connective tissue. Results demonstrated that topographic nature of the healing abutments can positively influence mucosal wound healing and molecular expression. Previous studies have been demonstrated how laser treatment can rightly influence integrity and functionality of the gingiva epithelium and cell adhesion. Regarding connective tissue different molecular expression demonstrated a different inflammatory pattern between laser treated or machined surfaces where laser treated showed better response. Targeted interventions and preventive measures on peri- implant topography could effectively minimize the risk of peri-implant diseases contributing to the long-term success and durability of restoration. However, new studies are mandatory to better understand this phenomenon and the role of this surface in the peri-implantitis process.  TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT05754970 ). Registered 06/03/2023, retrospectively registered.

Assessment of the Vanillin Anti-Inflammatory and Regenerative Potentials in Inflamed Primary Human Gingival Fibroblast.

BACKGROUND: Inflammatory responses have been associated with delayed oral mucosal wound healing and the pathogenesis of the periodontal disease. The invasion of microbes into the tissues and the establishment of a chronic infection may be due to impaired healing. The protracted inflammatory phase may delay wound healing and probably support tissue fibrosis and reduce tissue regeneration. Vanillin is a well-known natural compound with potential anti-inflammatory capacity. Hence, we hypothesized that Vanillin could accelerate wound healing reducing inflammation and especially cytokine production making the oral tissue repair process easier. METHODS: Our hypothesis was tested using primary human gingival fibroblast (HGF) cell pretreated with Vanillin and primed with IL-1ß, as inductor of proinflammatory environment. After 24 hours of treatments, the gene expression and production of IL-6, TNF-α, IL-8, COX-2, iNOS, and nitric oxide (NO) generation and the wound healing rate were determined. RESULTS: In IL-1ß-primed cells, preincubation with Vanillin reduced IL-6, IL-8, COX-2, and iNOS expression and NO release, compared to IL-1ß-primed cells. Moreover, Vanillin determines the increased gene expression of nAChRα7, leading us to hypothesize a role of Vanillin in the activation of the cholinergic anti-inflammatory pathway. Furthermore, in presence of mechanical injury, the Vanillin preincubation, wound closure may be reducing the expression and release of IL-6 and TNF-α and upregulation of COX-2 and IL-8. CONCLUSION: Together, the results of this study highlight the anti-inflammatory and tissue repair ability of Vanillin in IL-1ß-primed HGF. Therefore, Vanillin shows a potential therapeutic interest as an inflammatory modulator molecule with novel application in periodontal regeneration and oral health.

Collagen Fibres Orientation in the Bone Matrix around Dental Implants: Does the Implant's Thread Design Play a Role?

The aim of this study was to analyse the influence of different thread shapes of titanium dental implant on the bone collagen fibre orientation (BCFO) around loaded implants. Twenty titanium dental implants, divided for thread shapes in six groups (A-F) were analysed in the present study. All implants were immediately loaded and left in function for 6 months before retrieval. The parameters evaluated under scanning electron microscope were the thread width, thread depth, top radius of curvature, flank angle, and the inter-thread straight section. Two undecalcified histological sections were prepared from each implant. Birefringence analysis using circularly polarized light microscopy was used to quantitively measure BCFO. For groups A-F, respectively, transverse BCFO was 32.7%, 24.1%, 22.3%, 18.2%, 32.4%, and 21.2%, longitudinal BCFO was 28.2%, 14.5%, 44.9%, 33.1%, 37.7%, and 40.2%. The percentage differences between transverse and longitudinal orientation were 4.50% (A), 9.60% (B), -22.60% (C), -14.90% (D), -5.30% (E), and -19.00% (F). Following loading, the amount of transverse and longitudinal BCFO were significantly influenced by the thread shape. The greater flank angles and narrower inter-thread sections of the "V" shaped and "concave" shaped implant threads of groups A and B, respectively, promoted the predominance of transverse BCFO, compared to groups C-F (p < 0.05). A narrow inter-thread straight section promotes transverse BCFO, as do "V" shaped and "concave" shaped threads, which can thus be considered desirable design for implant threads.

Evaluation of Salivary Cytokines and Vitamin D Levels in Periodontopathic Patients.

Periodontal disease (PD) is an inflammatory condition of the tissues supporting the teeth, which is widespread among the adult population. Evidence shows a relationship between PD and vitamin D levels, which is involved in the regulation of bone metabolism, mineral homeostasis, and inflammatory response. This study aimed to perform a simultaneous evaluation of inflammatory mediators and vitamin D levels in saliva in periodontopathic patients to better understand their role in periodontal disease. In this observational study, clinical periodontal parameter examination was performed for each patient. Moreover, the saliva levels of 25(OH)D3, TGFß, IL-35, IL-17A, and MMP9 were evaluated using an ELISA assay. An increase in TGFß, IL-35, MMP9, and IL-17A salivary levels and a reduction in 25(OH)D3 levels were observed in periodontopathic patients with respect to the healthy controls. The present study revealed significant positive correlation between cytokines and highly negative correlation between 25(OH)D3 and salivary cytokine levels. Further studies are needed to better understand if salivary cytokines and vitamin D evaluation may represent a new approach for detection and prevention of progressive diseases, such as PD.

Gingival Response to Dental Implant: Comparison Study on the Effects of New Nanopored Laser-Treated vs. Traditional Healing Abutments.

The health of peri-implant soft tissues is important for the long-term success rate of dental implants and the surface topography is pivotal in influencing it. Thus, the aim of this study was to evaluate, in human patients, the inflammatory mucosal microenvironment in the tissue surrounding a new, nanoscale, laser-treated healing abutment characterized by engineered nanopores versus a standard machined-surface. Analyses of anti- and pro-inflammatory markers, cytokeratins, desmosomal proteins and scanning electron microscopy were performed in 30 soft-tissue biopsies retrieved during second-stage surgery. The results demonstrate that the soft tissue surrounding the laser-treated surface was characterized by a lower grade of inflammation than the one facing the machined-surface, which, in turn, showed a disrupted epithelium and altered desmosomes. Moreover, higher adhesion of the epithelial cells on the laser-treated surface was detected compared to the machined one. In conclusion, the laser-treated surface topography seems to play an important role not only in cell adhesion, but also on the inflammatory makers' expression of the soft tissue microenvironment. Thus, from a clinical point of view, the use of this kind of topography may be of crucial importance not only on healing abutments but also on prosthetic ones.

AEDG Peptide (Epitalon) Stimulates Gene Expression and Protein Synthesis during Neurogenesis: Possible Epigenetic Mechanism.

It was shown that AEDG peptide (Ala-Glu-Asp-Gly, Epitalon) regulates the function of the pineal gland, the retina, and the brain. AEDG peptide increases longevity in animals and decreases experimental cancerogenesis. AEDG peptide induces neuronal cell differentiation in retinal and human periodontal ligament stem cells. The aim of the study was to investigate the influence of AEDG peptide on neurogenic differentiation gene expression and protein synthesis in human gingival mesenchymal stem cells, and to suggest the basis for the epigenetic mechanism of this process. AEDG peptide increased the synthesis of neurogenic differentiation markers: Nestin, GAP43, ß Tubulin III, Doublecortin in hGMSCs. AEDG peptide increased Nestin, GAP43, ß Tubulin III and Doublecortin mRNA expression by 1.6-1.8 times in hGMSCs. Molecular modelling method showed, that AEDG peptide preferably binds with H1/6 and H1/3 histones in His-Pro-Ser-Tyr-Met-Ala-His-Pro-Ala-Arg-Lys and Tyr-Arg-Lys-Thr-Gln sites, which interact with DNA. These results correspond to previous experimental data. AEDG peptide and histones H1/3, H1/6 binding may be one of the mechanisms which provides an increase of Nestin, GAP43, ß Tubulin III, and Doublecortin neuronal differentiation gene transcription. AEDG peptide can epigenetically regulate neuronal differentiation gene expression and protein synthesis in human stem cells.

The Relationship Between Time of Retightening and Preload Loss of Abutment Screws for Two Different Implant Designs: An In Vitro Study.

The loosening of an abutment screw is one of the most frequent complications in implant-prosthetic rehabilitation, especially for single-crown cemented prostheses. This complication is due to several mechanical factors including type of connection, abutment-screw geometry, settling effects, and cyclical load. The purpose of the present in vitro study was to compare and associate different times of retightening with reductions in preload losses. We evaluated 40 internal hexagon dental implants and 40 external hexagon dental implants, with their related abutment screws. The implants were embedded in acrylic resin in cylindrical polyvinyl chloride tubes (26 mm diameter, 20 mm height). The abutments were fixed to the implants with screws to an initial torque of 35 Ncm using a digital torque meter with decimal precision. Two different types of connection were randomly divided in 4 subgroups of 10 samples each. One subgroup was used as control. The test groups underwent retightening to the same initial torque at increasing times from initial torque application for tightening of the abutment screws, to their retightening at 2 minutes, 5 minutes, and 10 minutes. The retightening time of 2 minutes shows significantly reduced preload loss. Randomized clinical trials are strongly required to provide clinicians with a beneficial standardized protocol of retightening that can be applied in routine clinical practice.

Human Gingival Fibroblasts Exposed to Extremely Low-Frequency Electromagnetic Fields: In Vitro Model of Wound-Healing Improvement.

Several clinical studies have suggested the impact of sinusoidal and pulsed electromagnetic fields in quickening wound repair processes and tissue regeneration. The clinical use of extremely low-frequency electromagnetic fields could represent a novel frontier in tissue repair and oral health, with an interesting clinical perspective. The present study aimed to evaluate the effect of an extremely low-frequency sinusoidal electromagnetic field (SEMF) and an extremely low-frequency pulsed electromagnetic field (PEMF) with flux densities of 1 mT on a model of oral healing process using gingival fibroblasts. An in vitro mechanical injury was produced to evaluate wound healing, migration, viability, metabolism, and the expression of selected cytokines and protease genes in fibroblasts exposed to or not exposed to the SEMF and the PEMF. Interleukin 6 (IL-6), transforming growth factor beta 1 (TGF-ß), metalloproteinase 2 (MMP-2), monocyte chemoattractant protein 1 (MCP-1), inducible nitric oxide synthase (iNOS), and heme oxygenase 1 (HO-1) are involved in wound healing and tissue regeneration, favoring fibroblast proliferation, chemotaxis, and activation. Our results show that the exposure to each type of electromagnetic field increases the early expression of IL-6, TGF-ß, and iNOS, driving a shift from an inflammatory to a proliferative phase of wound repair. Additionally, a later induction of MMP-2, MCP-1, and HO-1 was observed after electromagnetic field exposure, which quickened the wound-healing process. Moreover, electromagnetic field exposure influenced the proliferation, migration, and metabolism of human gingival fibroblasts compared to sham-exposed cells. This study suggests that exposure to SEMF and PEMF could be an interesting new non-invasive treatment option for wound healing. However, additional studies are needed to elucidate the best exposure conditions to provide the desired in vivo treatment efficacy.

Endothelial committed oral stem cells as modelling in the relationship between periodontal and cardiovascular disease.

In the present study we have mimicked, in vitro, an inflammatory process using Lipopolysaccharide derived from Porphyromonas Gingivalis (LPS-G) and human Periodontal Ligament Stem Cells induced to endothelial differentiation (e-hPDLSCs). The research project has been organized into the three following steps: i) induction of hPDLSCs toward endothelial differentiation; ii) evaluation of the molecular signaling pathway involved in the response to the LPS-G, and iii) functional response evaluation of the living construct constituted by porcine decellularized valve/e-hPDLSCs treated with LPS-G. Obtained results showed that 5 µg/ml LPS-G stimulus provokes: a slowdown of cell growth starting from 24 hr and the release of IL6, IL8, and MCP1 molecules. Signaling network analyzed showed the activation of TLR4/ NFkB/ERK1/2/p-ERK1/2 signaling mediated by MyD88 in LPS-G stimulated e-hPDLSCs, moreover a time course put in evidence a nuclear traslocation of ERK1/2 and p-ERK1/2 in differentiated samples. Following, the ability of e-hPDLSCs to expand and colonize the decellularized porcine heart valves was appraised at ultrastructural level. Considering that, the Reactive Oxygen Species (ROS) play an important role in the progression and development of cardiovascular disease (CVD), in LPS-G living construct model e-hPDLSCs/decellularized porcine heart valves (dPHV), ROS production was assessed. Time lapse experiments evidenced that LPS-G provokes in e-hPDLSCs a rapid and sustained increase in ROS generation, negligible on undifferentiated cells. From obtained data, by multiparametric analyses, a reasonable conclusion may be that the inflammation process activated by LPS-G can affect endothelial cells and could represent in vivo a possible pathological and predictor state of CVD.

Evaluation of Fibrin Clot Attachment on Titanium Laser-Conditioned Surface Using Scanning Electron Microscopy.

OBJECTIVES: The study aimed to evaluate the effects of different titanium surface treatments on blood clot extension (bce). METHODS: A total of 54 titanium disks with machined surface (M), laser-conditioned surface (L), and grit-blasted surface (S) were used in the present study. The surface characteristics such as contact angles and the microroughness were determined on each group (n = 4). To evaluate the bce, 0.1 mL of human blood was dropped onto the surface of each specimen and left for 7 minutes at room temperature. After fixation, dehydration, and gold sputtering treatments, the specimens were observed under scanning electron microscope. The bce values were expressed as percentage of specimen surface covered by blood clot. RESULTS: The surface roughness (Ra ±â€Šstandard deviation [SD]) was 0.75 ±â€Š0.02 µm for M, 0.25 ±â€Š0.02 µm for L, and 1.30 ±â€Š0.03 µm for S. The contact angles measured in static conditions (WCA ±â€ŠSD) were 71 ±â€Š5.4° for M, 107 ±â€Š6.6° for L, and 91 ±â€Š7.2° for S. Regarding the bce (bce ±â€ŠSD) of M samples (65.5 ±â€Š4.3%) was statistically lower compared with both L (83.4 ±â€Š5.1%) and S samples (72.4 ±â€Š4.7%) (P < 0.05). Meanwhile, the L group showed the higher bce value. CONCLUSION: The present results suggest that the laser-conditioned surface may increase the wettability and bce.

Cone beam computed tomography for dental and maxillofacial imaging: technique improvement and low-dose protocols.

OBJECTIVE: The aim of this study was to evaluate images quality and radiation doses of Cone Beam Computed Tomography (CBCT) for dental and maxillofacial imaging testing five different acquisition protocols. METHODS: Dose measurements of different acquisition protocols were calculated for Pax Zenith three-dimensional (3D) Cone Beam (Vatech, Korea) and for conventional orthopantomography (OPT) and cephalometric skull imaging Ortophos (Sirona Dental Systems, Bernsheim, Germany). The absorbed organ doses were measured using an anthropomorphic phantom loaded with thermoluminescent dosimeters at 58 sites related to sensitive organs. Five different CBCT protocols were evaluated for image quality and radiation doses. They differed in FOV, image resolution, kVp, mA, acquisition time in seconds and radiation dose. Measurements were then carried out with the orthopantomograph. Equivalent and effective doses were calculated. RESULTS: The reference protocol with large FOV, high resolution quality images, 95 kVp, 5 mA and acquisition time of 24 s resulted in a DAP value of 1556 mGy cm2 instead the protocol with reduced kVp from 95 to 80 kVp translated into a value of DAP inferior to 35% (from 1556 to 1013 mGy cm2). Going from a high resolution to a normal resolution, there was a reduction of the acquisition time to 15 s which allowed further dose reduction of approximately 40% (628 mGy cm2); this protocol resulted in a value of effective dose of 35 microSievert (µSv). Moreover, the effect of changing FOV has been evaluated, considering two scans with a reduced FOV (160 × 140  and 120 × 90 mm, respectively). CONCLUSIONS: CBCT low-dose protocol with large FOV, normal resolution quality images, 80 kVp, 5 mA and acquisition time of 15 s resulted in a value of effective dose of 35 microSievert (µSv). This protocol allows the study of maxillofacial region with high quality of images and a very low radiation dose and, therefore, could be proposed in selected case where a complete assessment of dental and maxillofacial region is useful for treatment planning.

Impact of Second Stage Surgery on Bone Remodeling Around New Hybrid Titanium Implants: A Prospective Clinical Study in Humans.

OBJECTIVE: The present prospective study aimed to more precisely identify the time points of bone changes around hybrid titanium implants up to 30 months of follow-up. MATERIALS AND METHODS: Twelve hybrid T3 implants (Biomet 3i) were placed in 9 healthy patients with the 2-stage surgical approach. Standardized digital Rx were taken at implant insertion (T0); healing-abutment connection after 3.1 ± 0.2 weeks (TX); loading stage after 7.5 ± 0.6 weeks (T1); after 12 months (T2); and after 30 months (T3) of functional loading. The marginal bone loss was digitally measured. RESULTS: The mean marginal bone loss was 0.76 ± 0.37 mm after 30 months. More than 60% (0.42 ± 0.29 mm) of the bone loss took place at healing-abutment connection (TX-T1). No statistically significant bone loss was found between T1-T2 and T2-T3, after 12 and 30 months, respectively. Approximately 40% of bone loss (0.34 mm) was noted between T1 and T3 (P < 0.05), which corresponds to the loading period. CONCLUSIONS: The implant-oral environment connection represents a critical step point in crestal bone loss. The amount of marginal bone loss, measured after 30 months of loading (T1-T3), was much less than that reported in the literature, showing that correct loading has a minor impact on the periimplant bone remodeling as compared to surgical implant reopening.

Porphyromonas gingivalis biofilm formation in different titanium surfaces, an in vitro study.

OBJECTIVE: The aim of this work was to evaluate the biofilm formation of Porphyromonas gingivalis on disks of titanium (Ti) grade 4 (G4) and Ti-6Al-4V alloy grade 5 (G5) with different surface topographies. MATERIALS AND METHODS: Porphyromonas gingivalis ATCC 33277 was used to develop an in vitro mature biofilm on a total of 96 disk-shaped specimens of laser-treated (L), sandblasted (S), and machined (M) surfaces of Ti G4 and Ti G5. Surface roughness (Ra) and the wettability contact angle (WCA) were measured to characterize the surface of the specimens. The bacterial biofilm was evaluated by biomass quantification, bacterial viability, visualization of the biofilm extracellular matrix, and bacterial cell count. Data were analyzed using one-way ANOVA and Holm-Sidak tests and expressed as mean ± standard deviation. RESULTS: The Ra for the L group was 0.10 (±0.07) µm inside the craters and 0.40 (±0.08) µm in the area surrounding the craters resulting the smoothest (P < 0.05) in respect to the S group (1.30 ± 0.61 µm) and the M group (0.75 ± 0.23 µm). The L group showed a higher WCA than S and M groups for both G4 (109.9° ± 6.6) and G5 (104.2° ± 5.9) materials (P < 0.05). The L group displayed both the less P. gingivalis bacterial biomass (0.38 ± 0.01 for G4; 0.62 ± 0.02 for G5) that was significant in respect to G4-S (P < 0.001), G4-M (P < 0.001), and G5-M (P = 0.001) and the less total cell number (215 ± 18 for G4 and 244 ± 9 for G5) than S and M groups for both G4 and G5 materials (P < 0.01). CONCLUSION: Within the limits of the present study, the results showed that G4-L appears to be significantly efficient in the reduction of the P. gingivalis biofilm formation.

The Effects of High Insertion Torque Versus Low Insertion Torque on Marginal Bone Resorption and Implant Failure Rates: A Systematic Review With Meta-Analyses.

OBJECTIVES: The aim was to analyze the data about the effects on marginal bone resorption and implant failure rates between implants inserted with high or low insertion torque values. MATERIALS AND METHODS: A systematic literature search until July 2015 was conducted. Data were summarized qualitatively in descriptive tables and quantitatively by performing random effects meta-analyses of effect sizes (ESs) for bone resorption and bone-to-implant contact (BIC) and relative risks (RRs) for implant failures. Risk of bias assessments were performed using the Cochrane tool for human studies and the SYRCLE's tool for animal studies. RESULTS: Four studies in humans and 6 quasirandomized animal studies were included. A total of 591 implants were evaluated qualitatively: 348 installed with high insertion torque (>25 Ncm, up to 176 Ncm) and 243 implants inserted with low torque values (<30-35 Ncm). No significant differences were detected for bone resorption (ES, 0.13; 95% confidence interval [CI], -0.12 to 0.38 in human studies; ES predictive interval from 35.03 to 34.50 in animal studies), implant failure (RR, 0.39; 95% CI, 0.01-20.77 in human studies; RR, 2.05; 95% CI, 0.19-21.71 in animal studies), or BIC (ES predictive interval from -3.84 to 5.13 in animal studies). CONCLUSION: The current review indicated that there is no significant difference in marginal bone resorption and implant failure rate between implants inserted with high or low insertion torque values.

Age estimation from canine volumes.

Techniques for estimation of biological age are constantly evolving and are finding daily application in the forensic radiology field in cases concerning the estimation of the chronological age of a corpse in order to reconstruct the biological profile, or of a living subject, for example in cases of immigration of people without identity papers from a civil registry. The deposition of teeth secondary dentine and consequent decrease of pulp chamber in size are well known as aging phenomena, and they have been applied to the forensic context by the development of age estimation procedures, such as Kvaal-Solheim and Cameriere methods. The present study takes into consideration canines pulp chamber volume related to the entire teeth volume, with the aim of proposing new regression formulae for age estimation using 91 cone beam computerized scans and a freeware open-source software, in order to permit affordable reproducibility of volumes calculation.

Evaluation of defects in surface detail for monophase, 2-phase, and 3-phase impression techniques: an in vitro study.

STATEMENT OF THE PROBLEM: Polyvinyl siloxane materials of various consistencies have been tested to reduce defects commonly associated with different definitive impression techniques. PURPOSE: The purpose of this in vitro study was to compare the number of visible defects within the surface of a new 3-phase, 2-step impression injection technique with the number found in the monophase and in the conventional 2-phase, 1-step and 2-phase, 2-step impression techniques. MATERIAL AND METHODS: Two complete crown abutment preparations were impressed 10 times for each of these 4 techniques, which gave 20 abutment impressions for each group. The 3-phase, 2-step impression--injection technique included extra-light--body impression material added for the impression and injected after reinsertion. After the removal of all of these impressions, an examiner counted the number of open voids and bubble-like enclosed voids visible to the naked eye at a working distance of approximately 150 mm. Only the defects in the area of the prepared abutments were included in the assessment. RESULTS: The frequency of defects ranged from 100% of the impressions in the monophase group to 5% with the new 3-phase, 2-step impression injection technique. No statistical differences were seen between the two 2-phase (1-step and 2-step) impression techniques, although there were numerically fewer impressions with defects with 2 steps (45%) than with 1 step (55%). The 3-phase, 2-step impression injection technique had the greatest accuracy, with fewer specimens with defects (5%) than with either of the 2-phase techniques, although these differences did not reach statistical significance. CONCLUSIONS: The 3-phase, 2-step impression injection technique provides improved defect-free reproduction of detail, showing fewer defects than other impression techniques.

Expression of P2X7 ATP receptor mediating the IL8 and CCL20 release in human periodontal ligament stem cells.

ATP is released by human periodontal ligament cells (hPDLCs) and has been shown to regulate PDL regeneration and responses to mechanical stress through activation of P2Y receptors. This nucleotide, however, has also been reported to trigger the pro-inflammatory cascade by inducing the maturation and/or release of chemokines/cytokines from various cell types mainly via P2X7 receptors. Much less is known on the possible role of ATP in stem cells deriving from PDL (hPDLSCs) which are considered to be a promising tool for cell-based therapy to restore lesions. Given the role played by P2X7 in pathophysiological conditions, in this study we investigated the expression of P2X7 ATP receptors in hPDLSCs. The results obtained showed that hPDLSCs express P2X7 receptors evaluated by means of cytofluorimetric, immunohistochemistry, reverse transcriptase-PCR, and Western blot analyses. P2X7 ligation by 2',3'-(benzoyl-4-benzoyl)-ATP (BzATP), a specific receptor agonist, was followed by an increase in intracellular Ca2+ and in the uptake of ethidium bromide. These effects were dramatically reduced by oxidized ATP (oATP), the P2X7 irreversible inhibitor, suggesting that the P2X7 is the functional receptor involved. At 24 h treatment of hPDLSCs with BzATP it enhanced the release of the pro-inflammatory agents IL8 and CCL20, without influencing cell viability. These effects were counteracted by pre-treating the cells with oATP or with A-740003, a selective and potent P2X7 competitive antagonist. Collectively, these results indicated that extracellular ATP mediate a pro-inflammatory response via P2X7 receptors in hPDLSCs opening a further approach to control hPDLSCs behavior in their possible application as therapeutic tool.