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Background: Carious/Non-carious cervical lesions with gingival recessions may require both dental and periodontal reconstructive therapy, where flaps/grafts may be placed in contact with a dental filling material. Human Gingival Fibroblasts (HGF-1) response during the early phase of healing could vary according to the procedures employed to cure the dental composite. Moreover, oxygen diffusion into dental composite inhibits the polymerization reaction, creating an oxygen-inhibited layer (OIL) that presents residual unreacted monomers. The aim of this study was to assess the effect of different polishing techniques and OIL on HGF-1. Methods: Composite discs polished with different techniques (diamond rubber, abrasive discs and tungsten carbide burr) were used. An additional not polished smooth group obtained with and without OIL was used as control. Samples were physically characterized through the analysis of their hydrophilicity and surface topography through contact angle measurement and SEM, respectively; afterwards the biologic response of HGF-1 when cultured on the different substrates was analyzed in terms of cytotoxicity and gene expression. Results: The finishing systems caused alterations to the wettability, even if without a proportional relation towards the results of the proliferation essay, from which emerges a greater proliferation on surfaces polished with one-step diamond rubber and with abrasive discs as well as a direct effect of the glycerin layer, confirming that surface roughness can heavily influence the biological response of HGF-1. Conclusions: Surfaces wettability as well as cellular behavior seem to be affected by the selection of the finishing system used to lastly shape the restoration. Especially, the presence of OIL act as a negative factor in the regards of human gingival fibroblasts. The present study may provide the first clinical instruction regarding the best polishing system of composite material when the restoration is placed directly in contact with soft tissue cells. Understanding HGF-1 behavior can help identifying the polishing treatment for direct restoration of carious/non-carious cervical lesions associated with gingival recessions. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review was to evaluate whether there are scientific evidence regarding the association between periodontitis and obstructive sleep apnea (OSA) in adults. An electronic search was performed on MEDLINE/PubMed for prospective and retrospective longitudinal studies, cohort studies, and case-control studies conducted in human adults affected by both OSA and periodontitis. Two reviewers extracted the data using a custom Excel spreadsheet. A methodological assessment of the quality of the studies was performed using the Newcastle-Ottawa Scale. Fourteen studies were included. All studies evaluated the association between periodontitis and OSA. None of the studies evaluated the cause-effect relationship. Eleven studies found a significant positive relationship between periodontitis and OSA, whereas three found no statistically significant association. Several study limitations were observed, such as lack of standardization of study groups, diagnosis of periodontitis and OSA, and differences in study design. Evidence of a plausible association between periodontitis and OSA was found. The possible relationship could be explained by systemic inflammation, oral breathing, and the comorbid relationship attributable to common risk factors. Observational and randomized controlled studies are needed to clarify the mechanism of interaction between the two conditions. [ABSTRACT FROM AUTHOR]

This article proposes a digital procedure to create the emergence profile of prosthetic crowns for teeth prepared with the Vertical Edgeless Preparation (VEP) technique. This technique extends the tooth preparation below the gingival margin on the root surface of teeth with reduced periodontal attachment. The tooth prepared according to this technique does not present a defined prosthetic margin or the relative finishing line. Still, it shows an edgeless axial wall that emerges from the gingival sulcus. The digital procedure for creating a prosthetic emergence profile, although representing a novelty in absolute terms, is based on traditional concepts, as they have been known and described in the literature for a long time. This article will explain and review the various clinical and laboratory steps necessary to produce, through an entirely digital procedure, a fixed partial denture composed of three zirconia elements, which are going to be subsequently veneered in a traditional way on the vestibular side to improve the esthetic appearance. [ABSTRACT FROM AUTHOR]

Objectives: The present study aimed to analyze the behaviors of three intraoral scanners (IOSs): evaluating the interdistance and axial inclination discrepancies in full-arch scans, predictable errors were searched. Materials and methods: Six edentulous sample models with variable numbers of dental implants were used; reference data were obtained with a coordinate-measuring machine (CMM). Each IOS (i.e., Primescan, CS3600, and Trios3) performed 10 scans per model (180 total scans). The origin of each scan body was used as a reference point to measure interdistance lengths and axial inclinations. Precision and trueness of interdistance measurements and axial inclinations were evaluated to address error predictability. Bland–Altman analysis, followed by linear regression analysis and Friedman's test (plus Dunn's post hoc correction), was performed to evaluate the precision and trueness. Results: Regarding interdistance, Primescan showed the best precision (mean ± SD: 0.047 ± 0.020 mm), while Trios3 underestimated the reference value more than the others (p < 0.001) and had the worst performance (mean ± SD: −0.079 ± 0.048 mm). Concerning the inclination angle, Primescan and Trios3 tended to overestimate angle values, while CS3600 underestimated them. Primescan had fewer inclination angle outliers, but it tended to add 0.4–0.6° to the measurements. Conclusions: IOSs showed predictable errors: they tended to overestimate or underestimate linear measurements and axial inclinations of scan bodies, one added 0.4–0.6° to the angle inclination values. In particular, they showed heteroscedasticity, a behavior probably related to the software or the device itself. Clinical significance: IOSs showed predictable errors that could affect clinical success. When performing a scan or choosing a scanner, clinicians should clearly know their behaviors. [ABSTRACT FROM AUTHOR]

This article aims to describe Vertical Edgeless Preparation (VEP), a full-crown vertical preparation technique initially introduced by the Porta Mascarella Group in the 1980s. The method is defined as "periodontally driven" because its main indication is teeth with a loss of periodontal attachment, and it aims to obtain healthier periodontal tissues. This work describes the step-by-step procedure for performing this prosthetic technique and its indications, contraindications, impression phases, temporary crown management, and its biological concept of periodontal dominance. [ABSTRACT FROM AUTHOR]

The aim of our study was to investigate how endodontics is taught in Italian universities. An online survey was conducted from August to December 2021. A comparison between courses led by full or associate professors (Group 1) versus courses led by other figures, such as researchers or temporary lecturers (Group 2), was made. A total of 28 out of 36 schools participated (78%). In most schools, endodontics is taught in the fifth year to 15–29 students. All schools planned pre-clinical endodontic training, and in 25/28 schools (89.3%), clinical endodontic training was also provided. The course programs varied among schools, and significantly more hours were allocated to teaching nonsurgical root canal treatment in Group 1 schools than in Group 2 schools. The average numbers of hours of preclinical and clinical training were 34.3 ± 23.6 and 84.1 ± 76.7, respectively. All schools used rotary NiTi files in their clinical training, and the vertical condensation of hot gutta-percha was the most frequently taught obturation technique. As expected, the scenario of endodontic education in Italian universities was variable and needs harmonization. Courses led by full or associate professors seem to be better structured. [ABSTRACT FROM AUTHOR]

The study of the intimate connection occurring at the interface between cells and titanium implant surfaces is a major challenge for dental materials scientists. Indeed, several imaging techniques have been developed and optimized in the last decades, but an optimal method has not been described yet. The combination of the scanning electron microscopy (SEM) with a focused ion beam (FIB), represents a pioneering and interesting tool to allow the investigation of the relationship occurring at the interface between cells and biomaterials, including titanium. However, major caveats concerning the nature of the biological structures, which are not conductive materials, and the physico-chemical properties of titanium (i.e. color, surface topography), require a fine and accurate preparation of the sample before its imaging. Hence, the aim of the present work is to provide a suitable protocol for cell-titanium sample preparation before imaging by SEM-FIB. The concepts presented in this paper are also transferrable to other fields of biomaterials research. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of the androgenic hormone testosterone enanthate (TE) on human MG-63 cells. MG-63 were cultured for 24 h in the presence of TE at increasing concentrations to assess its lethal dose. Therefore, the suitable concentration for a prolonged use of TE in vitro was assessed by viability assay over 9 days. Finally, MG-63 were exposed to TE for 14 days and assayed for differentiation by qPCR and Alizarin Red S staining. TE in the amount of 100 µM resulted as the maximum dose tolerated by MG-63 cells after 24 h. However, a prolonged exposure in culture TE in the amount of 100 µM showed a cytostatic effect on cell proliferation. On the contrary, TE 10 µM was tolerated by the cells and did not boost cell proliferation, but did enhance new bone formation, as revealed by COL1A1, ALPL, BGLAP, and IBSP gene expression after 3, 7, and 14 days, and calcium deposition by Alizarin Red S staining after 14 days. Based on the current study, 10 µM is the critical dose of TE that should be used in vitro to support bone differentiation of MG-63 cells. [ABSTRACT FROM AUTHOR]

An important issue with digital impression techniques is the difficulty in replicating the subgingival zone, particularly when abutments are prepared with a vertical finish line. We propose a novel procedure, the reverse subgingival scan (RSS), to depict the subgingival area via digital impression without a retraction cord or the distortion of the sulcus. The software workflow, beginning with a digital dental impression, was performed using Exocad® (Align Technology) and Meshmixer® (Autodesk). The approach is based on the direct alignment of the surface of abutments, which is used as a reference point. The efficacy of the RSS approach was confirmed via fit tests, radiographic control assessments, and evaluations of the rate of tissue compression of the final prosthetic restoration, so long as the provisional had a perfect fit. RSS yields information on the transversal dimension and depth of the gingival sulcus. The procedure depends on the quality and characteristics of the provisional restoration, and is suitable only for cases in which the finish line of the final crown is at the same level or more coronal than that of the provisional. [ABSTRACT FROM AUTHOR]

Background: Three millimeter is considered as the minimum distance to obtain soft and bone tissue stability in case of adjacent implants. The possibility to preserve peri‐implant bone level using a platform switching connection has questioned this concept. Purpose The study evaluates soft tissue maintenance and marginal bone stability around implants, placed at 2 or 3 mm of distance. Materials and methods: Thirty patients received two immediately loaded implants either at 2‐mm (test) or at 3‐mm (control) of distance in the premolar area. Soft tissue esthetics (papilla height and fill, keratinized tissue, recession) and radiographic peri‐implant bone level changes were measured at 3, 6, and 12 months. Results: No significant differences between the two groups were detected neither for all soft tissue esthetic outcomes nor for bone level modifications up to 12 months. Conclusion: The results suggested that up to 12 months post‐loading, both 2‐ and 3‐mm inter‐distance platform‐switched implants in healed site, supported adequate esthetic outcomes and peri‐implant bone stability. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review was to evaluate whether there are scientific evidence regarding the association between periodontitis and obstructive sleep apnea (OSA) in adults. An electronic search was performed on MEDLINE/PubMed for prospective and retrospective longitudinal studies, cohort studies, and case–control studies conducted in human adults affected by both OSA and periodontitis. Two reviewers extracted the data using a custom Excel spreadsheet. A methodological assessment of the quality of the studies was performed using the Newcastle–Ottawa Scale. Fourteen studies were included. All studies evaluated the association between periodontitis and OSA. None of the studies evaluated the cause–effect relationship. Eleven studies found a significant positive relationship between periodontitis and OSA, whereas three found no statistically significant association. Several study limitations were observed, such as lack of standardization of study groups, diagnosis of periodontitis and OSA, and differences in study design. Evidence of a plausible association between periodontitis and OSA was found. The possible relationship could be explained by systemic inflammation, oral breathing, and the comorbid relationship attributable to common risk factors. Observational and randomized controlled studies are needed to clarify the mechanism of interaction between the two conditions. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this case report is to show an effective and minimally invasive way to treat dentition which suffered the effects of severe acid erosion. Case Report: The patient was a 51-year-old man who presented with complaints about the appearance of his teeth. The patient reported he had been suffering from gastroesophageal reflux disease for 7 years and that he had not undergone any dental treatment except for 3 direct restorations performed 15 years before. Clinical and radiographical examinations showed a severely worn dentition presenting the typical pattern of acid erosion and a concrete loss in vertical dimension of occlusion (VDO). All teeth responded positively to the dental pulp vitality test, so it was decided to perform minimally invasive full-mouth restorations with lithium disilicate veneers to restore form and function of the dentition. First, the increase of VDO was determined. Then the Digital Smile Design (DSD) protocol was used to create a preview of the new shape and dimension of the teeth, produce a wax-up of the restored dentition, and two silicon indexes to create the mock-up. Subsequently, the mock-up on the worn teeth was printed and phonetic tests were performed. Since the patient was satisfied with the esthetics and function of the new dentition, we proceeded with our therapy plan. We performed a mock-up--driven preparation technique which resulted in minimally invasive preparations, and took VPS impressions for lithium disilicate veneers that were cemented in different appointments starting from the posterior areas, and carefully following the adhesive cementation protocol. Results: The rehabilitation successfully restored form and function of the dentition. At the 6-month recall, the patient was satisfied and the veneers were perfectly integrated with the surrounding soft tissues. Conclusion: In case of severe acid erosion, the presented protocol represents a viable, predictable, and minimally invasive therapeutic option. [ABSTRACT FROM AUTHOR]

The research in the field of biomaterials has largely focused on the development of methods to enhance their bioactivity. Adopted strategies include chemical-physical approaches, but mainly the use of monoclonal antibodies, which confer the system target specificity. However, antibodies are marred by numerous issues, such as low physical-chemical stability or the risk of inducing immunological responses in the host, which often make their use difficult. Aptamers - a new class of molecules discovered in the early nineties - are small oligonucleotides, or in some cases peptides, and have been proposed to rival antibodies in biomedicine, countering at least some of the antibody-related drawbacks. The aim of this review is to provide a background to nucleic acid aptamers and to explore their novel applications. In addition to providing brief overview of their therapeutics applications, here we have assessed the methods that employ aptamers to improve the bioactivity of biomaterials, in particular, those that enhance targeting properties of drug delivery systems for chemotherapy, and those ameliorating scaffold biocompatibility for tissue engineering approaches. [ABSTRACT FROM AUTHOR]

Background: Rough surface topography enhances the activation of Wnt canonical signaling, a pathway required for osteoblast differentiation. The present study investigated the effects of the modulation of prostaglandin E2 (PGE2) signaling on osteoblastic differentiation on titanium surfaces for endosseous implants with different topographies. Methods: C2C12 cells were plated on polished or acid-etched/sand-blasted (SLA) titanium discs and stimulated with 1 µM PGE2 or 100 nM cyclooxygenase inhibitor indomethacin. Activation of Wnt canonical signaling was measured with a reporter system. Gene expression was measured in the same cell system by real-time polymerase chain reaction (RT-PCR). Osteoblastic MC3T3 cells were then plated on polished or SLA titanium discs with or without indomethacin, and their proliferation and the expression of osteoblast-specific genes was assessed by RT-PCR. Cell morphology was furthermore studied on SEM, and cell adhesion was assessed by fluorescent labeling of focal adhesion. Results: PGE2 decreased Wnt signaling stimulation in cells growing on polished or SLA surfaces, while indomethacin increased the expression of Wnt target genes in C2C12 and MC3T3 cells, by reporter assay. Moreover, indomethacin increased the expression of early differentiation marker alkaline phosphatase in MC3T3 cells on polished discs and of late marker osteocalcin in cells on SLA titanium. Conclusions: Prostaglandin signaling affects the activation of Wnt canonical pathway in osteoblastic and mesenchymal cells on microstructured surfaces. [ABSTRACT FROM AUTHOR]

Trial Design. This analysis compared the outcome of fresh-frozen versus autologous bone block grafts for horizontal ridge augmentation in patients with Cawood and Howell class IV atrophies. Methods. Seventeen patients received autologous grafts and 21 patients received fresh-frozen bone grafts. Patients underwent CT scans 1 week and 6 months after surgery for graft volume and density analysis. Results. Two autologous and 3 fresh-frozen grafts failed. Autologous and fresh-frozen grafts lost, respectively, 28% and 46% of their initial volume (P = 0.028). It is noteworthy that less dense fresh-frozen blocks lost more volume than denser grafts (61% versus 16%). Conclusions. According to these 6-month results, only denser fresh-frozen bone graft may be an acceptable alternative to autologous bone for horizontal ridge augmentation. Further studies are needed to investigate its behaviour at longer time points. [ABSTRACT FROM AUTHOR]

Objectives. The goal of this study was to evaluate bone changes around endosseous implants in partially edentulous patients. Materials and Methods. A total of 632 two-stage implants were placed in 252 patients. The implants had straight emergence profile, ZirTi surface, 3.3 to 5mm diameter, and 8.5 to 13mm length. Bone levels were assessed on orthopantomography immediately after surgery and after 36 months and marginal bone loss (MBL) was calculated from their difference. Results. Cumulative survival rate was 98.73%. Overall MBL was 0.8mm ± 0.03 (mean ± SEM). Higher MBL was observed around implants in the maxilla than in the mandible (P; < 0.007). A relation between implant diameter and MBL (P; < 0.0001) was observed in male and, more limitedly, female patients. Older patients had higher MBL in the maxilla, but not in the mandible (P; < 0.0001). MBL progressively increased with age in male patients, but reached a peak already in the 50-60 years age group in the female subset (P; < 0.001). Conclusions. The overall MBL is consistent with the available literature. Site difference and patient age and gender appear to significantly affect MBL, representing important factors to be considered during implant placement. [ABSTRACT FROM AUTHOR]

The host-material interface is a crucial relationship dictating the possibility of successful osseointegration in implant dentistry. The aim of the present study was to characterize the effects of plasma proteins pre-adsorption on the adhesion capacity of osteoblasts, which occurs immediately after implant insertion in vivo. After having pre-adsorbed human plasma proteins on a machined and microrough titanium surface, MC3T3-E1 osteoblasts adhesion was evaluated through crystal violet cell adhesion assay, immunofluorescence staining for cytoskeleton, focal adhesions and cell nuclei, and scanning electron microscopy. The pre-adsorbed protein layer markedly affected the adhesion rate of cells, as well as their morphology and the expression of focal contacts. Moreover, protein adsorption to the underlying titanium surface was found to be correlated to surface pre-wetting. Thus, the early adsorption of serum proteins to the interface of dental implants impacts cell adhesion in terms of strength and of focal adhesions expression. [ABSTRACT FROM AUTHOR]

A decisive step in cell-biomaterial interaction is represented by the adsorption of proteins at the interface, whose fine control may be useful to trigger proper cell response. To this purpose, we can selectively control protein adsorption on biomaterials by means of aptamers. Aptamers selected to recognize fibronectin dramatically enhance chitosan ability to promote cell proliferation and adhesion, but the underlying biological mechanism remains unknown. We supposed that aptamers contributed to ameliorate the adsorption of fibronectin in an advantageous geometrical conformation for cells, thus regulating their morphology by the proper activation of the integrin-mediated pathway. We investigated this possibility by culturing epithelial cells on chitosan enriched with increasing doses of aptamers in the presence or in the absence of cytoskeleton pharmacological inhibitors. Our results showed that aptamers control cell morphology in a dose dependent manner (p < 0.0001). Simultaneously, when the inhibition of actin polymerization was induced, the control of cell morphology was attenuated (p < 0.0001), while no differences were detected when cells contractility was challenged (p > 0.05). Altogether, our data provide evidence that aptamers contribute to control fibronectin adsorption on biomaterials by preserving its conformation and thus function. Furthermore, our work provides a new insight into a new way to accurately tailor material surface bioactivity. [ABSTRACT FROM AUTHOR]

Background: The down‐regulation of Connexin 43 (CX43) hemichannels (HCs) function in soft tissue cells promotes the up‐regulation of numerous pro‐healing genes, as the down‐regulation of pro‐fibrotic ones, leading to its identification as a potential target for the modulation of wound healing. On the other hand, titanium is commonly used as a transmucosal material, both for dental implants and abutments, and its surface micro‐topography is known to affect cell responses. Aim/Hypothesis: To investigate whether threaded titanium surfaces with different groove characteristics modulate CX43 expression and its organization in HCs rather than in gap junction (GJs) in an immortalized mouse myoblast cell line. In addition, to verify if the growth pattern and arrangement of cells on the grooves. Material and Methods: Murine myoblasts C2C12 were seeded on discs with grooved titanium surfaces with different patterns‐ UTM (Ultrathin Threaded Microsurface) and XA microgrooved surface. A machined surface was used as control (MA). Titanium surface specimens were kindly provided by Sweden & Martina (Padova, Italy). Cells were cultured up to 7 days and daily monitored for viability through chemiluminescence (cell proliferation). Gene expression analysis for CX43, alkaline phosphatase (ALP) and collagen 1 (COL1a) was performed+ after 3 days of culture total RNA was purified, retro‐transcribed to cDNA and amplified through quantitative RT‐PCR. To localize the expression of CX43 and thus to identify its organization as HCs or as GJs, cells were observed under fluorescence after actin, CX43 and nuclei labeling. Differences among the groups were evaluated through Two‐Way ANOVA statistical test. Results: Very weak signal for CX43 was observed on UTM surface (mRNA 6.12‐fold less than XA and 2.58‐fold less than MA). CX43 expression was extremely up‐regulated on XA surface after 3 days, when compared to UTM and MA surface (_I_P_i_ < 0.0001). Conversely, cell proliferation was significantly reduced (_I_P_i_ < 0.0001). On the XA surface, CX43 expression was labelled in the peri‐nuclear area, indicating its organization in HCs. MA showed a slightly enhanced level of CX43 (2.37‐fold less than XA) and, where cells were confluent, CX43 signal was marked around cell nuclei (HCs) and at the edges of cell profile, indicating GJs with other cells. Noteworthy, the disposition of cells on XA and UTM surfaces followed the grid of the grooved surface topography, with cells laying on the grid hollows and elongated to colonize the surface. Furthermore, gene expression analysis revealed that MA control surface induced a commitment of C2C12 towards an osteoblastic phenotype, showing greater levels of ALP and COL1a. Conclusions and Clinical Implications: The microgrooved titanium surfaces showed a modulatory role on myoblasts, promoting an evident cell arrangement along the surface grooves on UTM and XA surfaces. This may lead in vivo to the deposition of an oriented extracellular matrix. Additionally, UTM surface caused CX43 down‐regulation, leading to the hypothesis of a more favorable in vivo soft tissues wound healing. [ABSTRACT FROM AUTHOR]

Tissue engineering (TE) is a multidisciplinary science, which including principles from material science, biology and medicine aims to develop biological substitutes to restore damaged tissues and organs. A major challenge in TE is the choice of suitable biomaterial to fabricate a scaffold that mimics native extracellular matrix guiding resident stem cells to regenerate the functional tissue. Ideally, the biomaterial should be tailored in order that the final scaffold would be (i) biodegradable to be gradually replaced by regenerating new tissue, (ii) mechanically similar to the tissue to regenerate, (iii) porous to allow cell growth as nutrient, oxygen and waste transport and (iv) bioactive to promote cell adhesion and differentiation. With this perspective, this review discusses the options and challenges facing biomaterial selection when a scaffold has to be designed. We highlight the possibilities in the final mold the materials should assume and the most effective techniques for its fabrication depending on the target tissue, including the alternatives to ameliorate its bioactivity. Furthermore, particular attention has been given to the influence that all these aspects have on resident cells considering the frontiers of materiobiology. In addition, a focus on chitosan as a versatile biomaterial for TE scaffold fabrication has been done, highlighting its latest advances in the literature on bone, skin, cartilage and cornea TE. [ABSTRACT FROM AUTHOR]