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Tooth extractions can result in alveolar bone dimensional changes, necessitating additional bone grafting for implant placement. Alveolar ridge preservation (ARP) aims to counteract postextraction changes. This case series evaluates the bone regenerative properties of a freeze-dried bone allograft (FDBA) and the clinical outcomes of implants in grafted extraction sites. A total of 33 patients were enrolled, undergoing single/multiple tooth extractions followed by ARP. Biopsy samples were harvested during implant placement for histologic and histomorphometric analysis. Clinical outcomes included marginal bone loss and pink esthetic score (PES). Twenty-five patients completed the study. FDBA-augmented sockets exhibited new bone formation adjacent to graft particles. Implants (n = 25) showed 100% survival and success rates at 1 and 2 years. PES improved significantly over time (P < .001), while marginal bone loss did not significantly differ at 1 and 2 years (P = .096). Specimens showed trabecular bone, residual FDBA particles, and marrow spaces. High magnification revealed immature bone and woven bone bridges around graft particles. No inflammatory cells were observed. This case series provides valuable insights into ARP performed with FDBA (as implants were placed after 3 months of healing without any additional bone augmentation), the histologic outcomes were favorable, and implants were successful after a 2-year follow-up period. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the influence of immediate loading on the osseointegration and bone density of implants placed in a healed alveolar bone crest and supporting single crowns. Materials and Methods: Two solid titanium transmucosal mini-implants were placed in the distal regions of the mandible in 14 patients. One mini-implant was immediately functionally loaded, whereas the other was left unloaded. After 2 months of healing, biopsy samples were retrieved and the levels of new bone, old bone, and total bone (new + old) were assessed. Results: Histologic examination was performed on biopsies from 12 patients (n = 12). The new bone-to-implant contact percentage (BIC%) was 40.3% ± 16.8% and 55.1% ± 19.1% (P = .043) at the unloaded and loaded sites, respectively; in addition, the total BIC% was 44.9% ± 17.0% and 59.5% ± 18.8%, respectively (P = .034). The new bone density was 45.9% ± 11.6% for the unloaded implants and 45.9% ± 16.7% for the loaded implants (P = .622). Conclusions: Immediate loading had a positive effect on bone apposition at the implant surface, but no effect on bone density was observed after 2 months of healing. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to assess the histomorphometric outcomes of extraction sockets grafted with freeze-dried bone allograft (FDBA) and sealed with a collagen membrane after 3 months of healing in specific region of interest (ROI) areas. The secondary aims were to analyze the biomaterial resorption rate, the bone-to-biomaterial contact (BBC), and the area and perimeter of grafted particles compared with commercially available FDBA particles. Fifteen patients underwent tooth extractions and ridge preservation procedures performed with FDBA and a collagen membrane. Bone biopsy samples were harvested after 3 months at the time of implant placement for histologic and histomorphometric analysis. Two areas of concern (ROI1 and ROI2) with different histologic features were identified within the biopsy samples; ROI1, ROI2, and commercially available particles were analyzed and compared. The following parameters were analyzed: newly formed bone, marrow space, residual graft particles, perimeter and area of FDBA particles, and BBC. The histomorphometric analysis showed 35.22% ± 10.79% newly formed bone, 52.55% ± 16.06% marrow spaces, and 12.41% ± 7.87% residual graft particles. Moreover, the histologic data from ROI1 and ROI2 showed that (1) the mean percentage of BBC was 64.61% ± 27.14%; (2) the newly formed bone was significantly higher in ROI1 than in ROI2; (3) the marrow space was significantly lower in ROI1 than in ROI2; and (4) the FDBA particles in ROI1 sites showed significantly lower area and perimeter when compared to commercially available FDBA particles. This latter data led to the hypothesis that FDBA particles embedded in newly formed bone undergo a resorption/remodeling process. [ABSTRACT FROM AUTHOR]

Objectives: This retrospective study compared the outcomes of implants placed in alveolar ridge preservation (ARP) treated sites with those in spontaneously healed (SH) sites. Materials and Methods: The study included patients presenting with one implant placed in an ARP‐treated socket and one in an SH site. The primary outcome was the comparison of Marginal Bone Level Changes (MBLC). Statistical analysis was performed to identify factors influencing MBLC, including age, gender, smoking, parafunctional habits, and prosthetic emergence angle. Results: Of these, 28 patients (23 females, 82.1%) were included in this analysis. Sockets in the SH group were classified as type I, whereas type II sockets were more common in the ARP group. The SH group exhibited significantly higher MBLC than the ARP group (p = 0.032), with values, respectively, of 1.00 [0.25; 1.62] and 0.40 [0.00; 1.00] mm. Among all evaluated parameters, the performance of ARP was the only factor significantly affecting MBLC (β = −0.72, SE: 0.32, p = 0.026). Age, gender, smoking, parafunctional habits, and prosthetic emergence angle did not significantly affect MBLC. Conclusions: The study shows the potential role of ARP in maintaining stable marginal bone levels around implants. In our sample, ARP significantly reduced MBLC compared with spontaneous healing, highlighting its possible impact in clinical practice for better peri‐implant bone stability. [ABSTRACT FROM AUTHOR]

Objectives: This systematic review aimed to analyse the published evidence for the use of non-invasive methods for the early detection of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). Methods: The literature was systematically searched through several databases: PubMed, Cochrane Library, and Web of Science. Additional exploration was performed through cross-checks on the bibliographies of selected reviews. The inclusion criteria involved studies assessing the application of non-invasive tests on humans in the screening, diagnosis, or surveillance of OSCC or OPMDs and reporting sensitivity (SE) and specificity (SP). The Newcastle–Ottawa scale (NOS) was applied to assess the quality of the studies included. Results: The search strategy resulted in 8012 preliminary records. After a duplicate check, 116 titles remained. After abstract analysis, 70 papers remained. After full text analysis, only 54 of the 70 papers fit the inclusion criteria (28 were original articles and 26 were reviews). Those 26 reviews were used to manually search for further original articles. From this last search, 33 original articles were found. Thus, a total of 61 original studies were included and investigated. Findings from this systematic review indicate useful information, such as a description of the mechanisms, ease of use, limitations, and SE and SP values, to drive the choice of the optimal minimally invasive method to be utilized as an adjunctive tool to examine the suspicious lesions. Conclusions: Each of the analysed tools can be improved or implemented, considering their high SE and low SP. Despite advancements, incisional biopsy continues to be the gold standard for the definitive diagnosis of oral cancer and precancerous lesions. Further research and development are essential to improving the sensitivity, specificity, and reliability of non-invasive tools for widespread clinical application. [ABSTRACT FROM AUTHOR]

The interaction between oral bacteria and dental implant surfaces is a critical factor in the success and longevity of dental implants. With advancements in additive manufacturing technologies, selective laser melting (SLM) has emerged as a prominent method for producing titanium implants with highly controlled microstructures and porosities. These 3D printed titanium surfaces offer significant benefits, such as enhanced osseointegration and improved mechanical properties. However, the same surface features that promote bone cell attachment and proliferation may also provide favorable conditions for bacterial adhesion and biofilm formation. Understanding the dynamics of these interactions is essential for developing implant surfaces that can effectively resist bacterial colonization while promoting tissue integration. This narrative review explores the complex interplay between oral bacteria and SLM-produced titanium porous surfaces, examining current research findings and potential strategies for optimizing implant design to mitigate the risks of infection and ensure successful clinical outcomes. [ABSTRACT FROM AUTHOR]

Oxidative stress and high levels of reactive oxygen species (ROS) are linked to various age-related diseases and chronic conditions, including damage to oral tissues. Dexamethasone (DEX), a widely used glucocorticoid in dentistry, can have side effects like increased ROS production and delayed wound healing. Resveratrol (RSV) is known for its antioxidant properties, but its limited bioavailability hinders its clinical use. This study investigated the potential of two RSV derivatives (1d and 1h) to address these limitations. The antioxidant abilities of 1d and 1h (5 μM) against DEX-induced oxidative stress (200 μM) were evaluated in human gingival fibroblasts (hGFs) and osteoblasts (hOBs). The effects of these compounds on cell viability, morphology, ROS levels, SOD activity, gene expression, and collagen production were evaluated. RSV derivatives, under DEX-induced oxidative stress condition, improved cell growth at 72 h (191.70 ± 10.92% for 1d+DEX and 184.80 ± 13.87% for 1h+DEX), morphology, and SOD activity (77.33 ± 3.35 OD for 1d+DEX; 76.87 ± 3.59 OD for 1h+DEX at 1 h), while reducing ROS levels (2417.33 ± 345.49 RFU for 1d+DEX and 1843.00 ± 98.53 RFU at 4 h), especially in hOBs. The co-treatment of RSV or derivatives with DEX restored the expression of genes that were downregulated by DEX, such as HO-1 (1.76 ± 0.05 for 1d+DEX and 1.79 ± 0.01 for 1h+DEX), CAT (0.97 ± 0.06 for 1d+DEX and 0.99 ± 0.03 for 1h+DEX), NRF2 (1.62 ± 0.04 for 1d+DEX and 1.91 ± 0.05 for 1h+DEX), SOD1 (1.63 ± 0.15 for 1d+DEX and 1.69 ± 0.04 for 1h+DEX). In addition, 1d and 1h preserved collagen production (111.79 ± 1.56 for 1d+DEX and 122.27 ± 1.56 for 1h+DEX). In conclusion, this study suggests that the RSV derivatives 1d and 1h hold promise as potential antioxidant agents to counteract DEX-induced oxidative stress. These findings contribute to the development of novel therapeutic strategies for managing oxidative stress-related oral conditions. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the ability of photodynamic therapy, based on the use of a gel containing 5% delta aminolaevulinic acid (ALAD) for 45′ followed by irradiation with 630 nm LED (PDT) for 7′, to eradicate Candida albicans strains without damaging the gingiva. C. albicans oral strains and gingival fibroblasts (hGFs) were used to achieve these goals. The potential antifungal effects on a clinical resistant C. albicans S5 strain were evaluated in terms of biofilm biomass, colony forming units (CFU/mL) count, cell viability by live/dead analysis, and fluidity membrane changes. Concerning the hGFs, viability assays, morphological analysis (optical, scanning electronic (SEM), and confocal laser scanning (CLSM) microscopes), and assays for reactive oxygen species (ROS) and collagen production were performed. ALAD-mediated aPDT (ALAD-aPDT) treatment showed significant anti-biofilm activity against C. albicans S5, as confirmed by a reduction in both the biofilm biomass and CFUs/mL. The cell viability was strongly affected by the treatment, while on the contrary, the fluidity of the membrane remained unchanged. The results for the hGFs showed an absence of cytotoxicity and no morphological differences in cells subjected to ALAD-aPDT expected for CLSM results that exhibited an increase in the thickening of actin filaments. ROS production was augmented only at 0 h and 3 h, while the collagen appeared enhanced 7 days after the treatment. [ABSTRACT FROM AUTHOR]

Organs-on-a-chip (OoCs) are microfluidic devices constituted by PDMS or hydrogel in which different layers of cells are separated by a semipermeable membrane. This technology can set many parameters, like fluid shear stress, chemical concentration gradient, tissue–organ interface, and cell interaction. The use of these devices in medical research permits the investigation of cell patterning, tissue–material interface, and organ–organ interaction, mimicking the complex structures and microenvironment of human and animal bodies. This technology allows us to reconstitute in vitro complex conditions that recapitulate in vivo environments. One of the main advantages of these systems is that they represent a very realistic model that, in many cases, can replace animal experimentation, eliminating costs and related ethical issues. Organ-on-a-chip can also contain bacteria or cancer cells. This technology could be beneficial in dentistry for testing novel antibacterial substances and biomaterials, performing studies on inflammatory disease, or planning preclinical studies. A significant number of publications and reviews have been published on this topic. Still, to our knowledge, they mainly focus on the materials used for fabrication and the different patterns of the chip applied to the experimentations. This review presents the most recent applications of organ-on-a-chip models in dentistry, starting from the reconstituted dental tissues to their clinical applications and future perspectives. [ABSTRACT FROM AUTHOR]

Bone blocks are proposed in oral bone regeneration for their biocompatibility and osteoconductivity. Human dental pulp stem cells (hDPSCs) have been used with bone substitutes as a biocomplex. Melatonin, produced by the pineal gland, has specific functions in the oral cavity in bone remodeling and enhancing the dual actions on osteoblasts and osteoclasts, the genic expression of bone markers. This study evaluated the osteogenic differentiation of hDPSCs, stimulated by melatonin on equine bone blocks. hDPSCs were cultured in growth medium (GM) or differentiation medium (DM) with or without the presence of equine bone blocks and 100 µm melatonin. After 7, 14, and 21 days of culture, expression of miRNAs (miR-133a, miR-133b, miR-135a, miR-29b, miR-206, and miR- let-7b) and genes (RUNX2, SMAD5, HDAC4, COL4a2, and COL5a3), osteocalcin levels and histolgic analyses were evaluated. Melatonin and equine blocks increased the osteogenic potential of hDPSCs even in GM, regulated miRNA and gene expression related to osteogenesis, and increased osteocalcin. hDPSCs cultured in DM showed a significantly higher osteogenic potential compared to GM. This study suggests that equine bone blocks and melatonin enhanced osteogenesis, stimulating early stages of cell differentiation. hDPSCs/equine bone block and melatonin represent a promising, useful biocomplex in bone regeneration with a potential for a possible clinical application. Int [ABSTRACT FROM AUTHOR]

Objectives: Alveolar ridge preservation (ARP) is a procedure with the aim to reduce bone resorption that occurs after tooth extraction, facilitating the following implant placement. The aim of this cross‐sectional study was to evaluate the prevalence of mucositis and peri‐implantitis around implants inserted in sites treated with ARP and to investigate possible risk factors. Materials and methods: Patients who received at least one dental implant inserted in a grafted socket were considered eligible for this study. Patients were recalled for a follow‐up visit; medical history, clinical and demographic data were collected. Univariate logistic regression analyses have been performed for both implant‐level and patient‐level variables. Indeed, moderation analysis was used to investigate the indirect relationship between age and marginal bone level. Results: Fifty‐one patients who received 61 implants were enrolled in this cross‐sectional study. Thirty‐three implants were classified as "healthy" (54.1%), 23 implants showed signs of peri‐implant mucositis (37.7%), and 5 implants were diagnosed with peri‐implantitis (8.2%). Data analyzed at the patient level showed that 49% of the patients were healthy, 45.1% of the patients had mucositis and 5.9% of the patients were affected by peri‐implantitis. Mandibular sites and type III grafted sockets showed a significant association with peri‐implantitis; in addition, a history of periodontitis and an increase in age showed higher risks of developing mucositis or peri‐implantitis. Conclusions: Implants inserted in grafted sockets showed favorable rates of healthy implants in the long term. Clinical relevance: The ridge preservation procedures do not seem to increase the risk of developing mucositis or peri‐implantitis. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present human observational study is to provide morphologic and morphometric analysis of peri‐implant connective tissue next to abutments with divergent or convergent macro‐geometry and different surface micro‐characteristics. Materials and Methods: Thirty patients were rehabilitated with single implants in the posterior area and one out of three different healing abutments with a one‐stage technique: machined divergent abutment (DIV‐MAC), machined convergent abutment (CONV‐MAC) or convergent abutment with ultrathin threaded surface (CONV‐UTM). At 3 months postimplant insertion, peri‐implant soft tissue was harvested; the following outcomes were investigated: histomorphometry (vertical width of connective and epithelial components) as detected by histology and polarized light; and connective tissue vertical width and 3D organization as detected by synchrotron‐based high‐resolution phase‐contrast‐based tomography (PhC‐μCT). Results: Significant differences in connective tissue vertical dimension (aJE‐AM) were found between DIV‐MAC and both CONV‐MAC and CONV‐UTM, both by histology and PhC‐μCT, with significantly higher values for the last two groups. Moreover, 2D histological analysis did not find significant differences in the junctional epithelium vertical dimension (PM‐aJE). Importantly, PhC‐μCT analysis revealed, at 3D level, significant greater amount and density of collagen bundles for CONV‐UTM compared with the other two groups. Conclusions: Convergent abutment profiles, regardless of their surface micro‐geometry, seem to favor axial development of peri‐implant connective tissue. Moreover, ultrathin threaded surfaces seem associated with denser and greater connective tissue organization, which might improve peri‐implant soft tissue seal. [ABSTRACT FROM AUTHOR]

The use of biomaterial for tissue repair involves the interaction between materials and cells, and the coagulum formation represents the first step of tissue healing. This process is particularly critical in the oral cavity, where the wounds are immediately subjected to the masticatory mechanical stress, saliva invasion, and bacterial attack. Therefore, the present study aimed to explore the structural features and the biological activities of a hemostatic collagen sponge on human gingival fibroblasts (HGFs) and human oral osteoblasts (HOBs). The microstructure of the collagen sponge was characterized by a scanning electron microscope (SEM) and histological analysis. The porosity was also calculated. To investigate biological activities, HGFs and HOBs were cultured on the collagen sponges, and their adhesion was observed at SEM on the third day, while cell viability was investigated at the third and seventh days by Tetrazolium (MTT) assay. For osteoblasts seeded on collagen sponge the mineralization ability was also evaluated by alkaline phosphatase (ALP) assay at the seventh day, and by Alizarin red staining on the 14th. Furthermore, the gene expression of ALP and osteocalcin (OCN) was investigated after 3, 7 and 14 days. SEM images of the sponge without cells showed a highly porous 3D structure, confirmed by the measurement of porosity that was more than 90%. The samples cultured were characterized by cells uniformly distributed and adhered to the sponge surface. Proliferation ended up being promoted, as well as the mineralization ability of the osteoblasts, mainly at the mature stage. In conclusion, this collagen sponge could have a potential use for tissue healing. [ABSTRACT FROM AUTHOR]

The study of the organizational kinetics in the area surrounding the transmucosal part of dental implants promises to ensure an accurate diagnosis of the healing process, in terms of osseointegration and long-term implant success. In this demonstrative work, the morphological, qualitative and quantitative characteristics of 3D images of collagen bundles obtained by synchrotron-based high-resolution X-ray tomography were analyzed. Data analysis was performed using deep learning algorithms, neural networks that were applied on multiple volumes extracted from connective portions of different patients. The neural network was trained with mutually consistent examples from different patients; in particular, we used a neural network model, U-Net, well established when applying deep learning to datasets of images. It was trained not only to distinguish the collagen fibers from the background, but also to subdivide the collagen bundles based on the orientation of the fibers. In fact, differently from conventional thresholding methods, deep learning semantic segmentation assigns a label to each pixel, not only relying on grey level distribution but also on the image morphometric (shape or direction) characteristics. With the exception of Pt2 biopsies that, as confirmed by the polarized light investigation, were shown to present an immature tissue condition, the quantity, the anisotropy degree and the connectivity density of transverse bundles were always demonstrated to be higher than for longitudinal ones. These are interesting and new data; indeed, as collagen bundles are organized in an intertwining pattern, these morphometric and 3D complexity parameters, distinguished in transversal and longitudinal directions, give precise indications on the amount and distribution of connective tissue forces exerted during the healing process. [ABSTRACT FROM AUTHOR]

This in vitro study aims to evaluate the bacterial microleakage of three conometric connections. Sixty dental implants (3P implafavourite Scalenghe) were divided in groups (n = 20): Cone–Morse with passing screw (Group 1); Cone–Morse with solid abutment (Group 2); and Conometric connection with esthetic abutment (Group 3). The implants were fixed in resin bases. Then, 1.0 µL of Streptococcus oralis (SO) was inoculated in the internal platform in 10 fixtures for each group, and another 10 were inoculated with Pseudomonas aeruginosa (PA). The abutments were then screwed, and five implants from each subgroup were randomly selected for SEM inspection to ensure that the abutments were installed correctly. Data were submitted to statistical analysis, ANOVA and Fisher's Least Significant Difference (p ≤ 0.05). The turbidity of the broth was monitored for 14 days of follow-up in order to determine the penetration of the bacterial suspension into the surrounding solution, but the observation of the samples lasted until the 90th day, in which there was no difference between the two. Microbial contamination was found in 30%, 20%, and 50% of Group 1, Group 2, and Group 3, respectively, but there were no statistically significant differences between the groups, and PA showed greater infiltration than SO. Although no statistically significant differences were found, cone morse connections showed lower infiltration percentages, respective to the conometric connection with 18° angle. [ABSTRACT FROM AUTHOR]

Recently, there has been an increasing interest in finding new approaches to manage oral wound healing. Although resveratrol (RSV) exhibited many biological properties, such as antioxidant and anti-inflammatory activities, its use as a drug is limited by unfavorable bioavailability. This study aimed to investigate a series of RSV derivatives (1a–j) with better pharmacokinetic profiles. At first, their cytocompatibility at different concentrations was tested on gingival fibroblasts (HGFs). Among them, derivatives 1d and 1h significantly increased cell viability compared to the reference compound RSV. Thus, 1d and 1h were investigated for cytotoxicity, proliferation, and gene expression in HGFs, endothelial cells (HUVECs), and oral osteoblasts (HOBs), which are the main cells involved in oral wound healing. For HUVECs and HGFs, the morphology was also evaluated, while for HOBs ALP and mineralization were observed. The results showed that both 1d and 1h did not exert negative effects on cell viability, and at a lower concentration (5 µM) both even significantly enhanced the proliferative rate, compared to RSV. The morphology observations pointed out that the density of HUVECs and HGFs was promoted by 1d and 1h (5 µM) and mineralization was promoted in HOBs. Moreover, 1d and 1h (5 µM) induced a higher eNOS mRNA level in HUVECs, higher COL1 mRNA in HGFs, and higher OCN in HOBs, compared to RSV. The appreciable physicochemical properties and good enzymatic and chemical stability of 1d and 1h, along with their promising biological properties, provide the scientific basis for further studies leading to the development of RSV-based agents useful in oral tissue repair. [ABSTRACT FROM AUTHOR]

The present study aims to discuss the main factors involving the use of 5-aminolevulinic acid together with red LED light and its application in endodontic treatment through a narrative review and a case report. Persistence of microorganisms remaining on chemical-mechanical preparation or intracanal dressing is reported as the leading cause of failure in endodontics. Photodynamic therapy has become a promising antimicrobial strategy as an aid to endodontic treatment. Being easy and quick to apply, it can be used both in a single session and in several sessions, as well as not allowing forms of microbial resistance. 5-aminolevulinic acid in combination with red LED light has recently been studied in many branches of medicine, with good results against numerous types of bacteria including Enterococuss faecalis. The case report showed how bacterial count of CFU decreased by half (210 CFU/mL), after 45 min of irrigation with a gel containing 5% of 5-aminolevulinic acid compared to the sample before irrigation (420 CFU/mL). The subsequent irradiation of red LED light for 7 min, the bacterial count was equal to 0. Thus, it is concluded that the use of 5-aminolevulinic acid together with red LED light is effective in endodontic treatment. [ABSTRACT FROM AUTHOR]