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The purpose of this preclinical study was to evaluate the influence of tamoxifen (TAM) on the peri-implant bone remodeling of osseointegrated titanium implants in ovariectomized female rats.Seventy-two female rats underwent bilateral ovariectomy 20 weeks before implants placement. One titanium implant was inserted in each tibia of the animals. Six weeks following the implant surgery, animals were randomly divided into two experimental groups (n = 36), which received either saline solution (SS) or tamoxifen citrate (TAM) via gavage until euthanasia. Euthanasia was performed at 30, 60, and 90 days after the first gavage. Assessments of bone to implant contact (BIC), bone ingrowth percentage (BIN), morphological description of cellular and tissue reactions, immunohistochemistry for the detection of bone morphogenetic protein 2/4 (BMP2/4), runt-related transcription factor 2 (RUNX-2), osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP), and bone chemical composition through scanning electron microscopy with energy-dispersive x-ray spectroscopy were performed.Tamoxifen group presented higher BIC, higher BIN, higher RUNX-2 and OCN, lower TRAP-positive cells/mmTamoxifen enhanced the remodeling of the bone surrounding titanium implants in ovariectomized rats.

Background Innovative customized computer-aided design/computer-assisted manufacture (CAD-CAM) titanium meshes have been proposed for guided alveolar bone regeneration. Histological confirmation on the quality of the regenerated bone is needed. Purpose of the study is to assess the integration capabilities of these innovative meshes and to evaluate the histological features of the regenerated alveolar bone. Materials and methods Twenty partially edentulous patients, with severe posterior mandibular atrophy, underwent a guided bone regeneration technique by means of customized CAD-CAM titanium mesh in association with a mixture of autologous bone in chips and deproteinized bovine bone (1:1). At 9 months of healing, titanium meshes and bone samples were collected and histomorphometrically analyzed. Results In all patients, implants were placed according to the original plan. At histologic analysis, mesh appeared well osseointegrated, except that in sites where membrane exposure occurred. In all sites, newly formed tissue resulted highly mineralized, well-organized, and formed by 35.88% of new lamellar bone, 16.42% of woven bone, 10.88% of osteoid matrix, 14.10% of grafted remnants, and 22.72% of medullary spaces. Blood vessels were the 4% of the tissue. Conclusions Data from this study support the use of customized CAD/CAM titanium mesh for regeneration of vital, well-structured, and vascularized alveolar bone.

Aim and objective The aim of this study is to provide preliminary retrospective evidence concerning the histologic and histomorphometric outcome of a novel freeze-dried equine-derived bone paste (EDEBEX) for ridge preservation of sockets following tooth extraction. Materials and methods This pilot retrospective case series describes the histologic and histomorphometric outcome of three patients who received the equine-derived bone paste in post-extractive sockets to allow the preservation of the alveolar ridge. Patients were later rehabilitated with monolithic-zirconia, implant-supported prostheses. Results All patients healed uneventfully. The collected biopsies showed a prevalence of bone formation at 4 months, compact lamellar bone, with well-defined lamellae surrounding Haversian and Volkmann's canals at 6 months, and an intermediate degree of maturation in active anabolic phase at 7 months after grafting. The amount of mineralized matrix was 63.3-70.7%, whereas medullar spaces were 26.0-30.7%. Conclusion Histologic examination showed that the bone paste was fully biocompatible. Bone regeneration occurred within the first 4 months from grafting, with 63.3-70.7% mineralized bone matrix. The residual biomaterial, when present, did not exceed, on average, 2%. Clinical significance Ridge preservation using bone substitutes as an alternative to autogenous bone is known to be effective. However, available clinical evidence still does not indicate the biomaterial, if any, that should be preferred to carry it out. The equine bone paste used in the present study appears to be a good candidate for further investigation because it is easy to handle in the clinical setting and it displays a good bone formation rate.

Background: No evidence has so far proven a significant role of schools in SARS-CoV-2 transmission, while the negative effects of their closure on children and adolescents are well documented. Surveillance, by means of frequent students and staff testing, has been advocated in order to implement school safety. Our aim was to report the results of a school surveillance program for the early detection of SARS-CoV-2 infection in pre- and asymptomatic subjects, by means of molecular salivary testing (MST). Methods: School surveillance in two schools in Milan, Italy, was carried out for six weeks. Each participant received a saliva collection kit, to be self-performed. Results: 401 students and 12 teachers were enrolled, and 5 positive children in 5 different classes were observed. All the cases were asymptomatic. Their nasopharyngeal swab was positive on the same day in four cases, while in one case it resulted negative on the same day and positive 3 days later. In one positive case, the whole family was set under surveillance. The positive child did not develop symptoms and no family member was infected. Conclusions: MST might represent an efficient way to actively survey communities in order to detect asymptomatic cases, thus limiting SARS-CoV-2 transmission.

Aims Genetic and environmental factors all interact in the risk of progression of valvular dysfunctions. Previous studies reported a relation between valve diseases and epicardial adipose tissue (EAT) thickness. The aim of this study was to verify the possible relationship between the molecular pattern of EAT related to IL-13 fibrogenic cytokine expression and valve dysfunction. Methods and results A valvular heart disease (VHD) population was stratified according to their median EAT thickness (7 mm). The molecular expression of IL-13 in EAT is directly related to the molecular expression of genes associated with extracellular matrix (ECM) turnover, macrophage infiltration and promotion of the formation of ectopic calcific nodules involved in aorta coarctation and calcification. Conclusion IL-13 gene expression in altered EAT is directly related to the expression of genes involved in ECM turnover and the formation of ectopic calcific nodules, suggesting measurements of EAT as a stratification risk factor for valve instability in the VHD patients.

Background and Objectives: Wound healing is a dynamic process that can be compromised in patients with chronic and metabolic conditions or unhealthy lifestyles. Numerous medical substances designed for topical use, charged with compounds that promote the healing process, have been developed to improve wound healing, especially in compromised subjects. The present study aimed to extend our understanding of the in vivo effects of a hyaluronic acid gel charged with amino acids (HAplus gel, Aminogam gel® Errekappa Euroterapici spa, Milan, Italy) and study the in vitro effects of the same gel charged with additional substances in an attempt to optimize its formulation. Materials and Methods: In a randomized controlled split-mouth clinical and histological trial, HAplus gel was tested on the gingival tissue of the lower third molar post-extraction socket. The gingiva was collected at the time of extraction (T0) and ten days after the extraction (T1) to be histologically analyzed. During the second stage of the study, culture media with HAplus gel and vitamin C and E at different concentrations (TEST) were tested on human gingival fibroblasts and compared to the HAplus-enriched medium (HA-Control). Results: Histological and immunohistochemical analysis of collected gingiva showed higher microvascular density and collagen fibers organized in closely packed and well-oriented bundles in sites treated with HAplus gel. In the in vitro study, all TEST groups showed an increased viability from 24 h to 48 h. After 24 h, the viability percentage in all experimental groups was below 100% of the HA-Control, demonstrating a mild toxicity. After 48 h from seeding, the TEST groups’ viability grew significantly compared to HA-Control. Conclusions: These encouraging preliminary results suggest that the use of HAplus gel enriched with vitamins C and E may be beneficial in patients with conditions that impair soft tissue healing.

Stainless steel implants are suitable candidates for bone replacement due to their cytocompatibility and mechanical resistance, but they suffer from lack of bioactivity and are prone to bacterial infections. Accordingly, to overcome those limitations, in this study we developed by electrophoretic deposition (EPD), an innovative surface coating made of (i) zein, a natural fibroblast-friendly polymer, (ii) bioactive glass, a pro-osteogenic inorganic material and (iii) copper containing bioactive glass, an antibacterial and pro-angiogenic material. FESEM images confirmed that porous, uniform and free of cracks coatings were obtained by EPD; moreover, coatings were resistant to mechanical stress as demonstrated by the tape test, resulting in a 4B classification of adhesion to the substrate. The coatings were cytocompatible as indicated by metabolism evaluation of human fibroblasts, endothelial cells and mature or progenitor osteoblasts cultivated in direct contact with the specimens. They also maintained pro-osteogenic properties towards undifferentiated progenitor cells that expressed osteogenic genes after 15 days of direct cultivation. Copper conferred antibacterial properties as biofilm formation of the joint pathogens Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli was significantly reduced in comparison with copper-free coatings (p, Graphical abstract Image 1, Highlights • Zein and copper doped bioactive glass combined in composite coating. • Coating was compatible with fibroblast, osteoblast progenitor and endothelial cells. • Copper was strongly antibacterial towards joint pathogens. • Copper promoted angiogenesis in vivo.

A large part of the Italian population doesn&rsquo, t receive adequate information and support on how to maintain oral health. In this observational, cross-sectional, pilot study, we investigated how some lifestyle-related variables affect oral diseases and oral health-related quality of life (OHRQoL) of children attending public-school summer services in Milan. A survey that included questions on children&rsquo, s oral disease, OHRQoL and lifestyle-related factors (feeding habits, oral hygiene protective behaviors, dental coaching and socio-economic and educational status), was administered to the children&rsquo, s caregivers. Data from 296 surveys were analyzed to assess the protective/negative effect of each variable on oral disease and OHRQoL. With respect to disease, the &ldquo, never&rdquo, consumption of fruit juice, the use of fluoride toothpaste, higher educational qualification and ISEE (equivalent family income) of those who filled out the form, resulted protective factors. Regarding OHRQoL, the &ldquo, assumption/use of tea bottle, sugared pacifier and fruit juice as well as the use of fluoride toothpaste, a higher educational qualification and ISEE of those who filled out the form, resulted to have protective effects. In conclusion, protective behaviors and socio-economic status affect oral disease and OHRQoL in children of Milan.

The additive manufacturing techniques (AM) are able to realize three-dimensional trabecular structures that mimic the trabecular structure of the bone. An in vivo study in sheep was carried out with the aim of assessing the bone response and the trend of osteointegration of a randomized trabecular titanium structure produced by the AM technique. In 6 sheep were implanted 84 specimens with a trabecular titanium structure (4 implants in the femur distal epiphysis; 4 implants in the tibial plate; 6 implants in the tibial shaft). Sheep were sacrificed at 3 postoperative time-points: 6 weeks, 10 weeks, 14 weeks. Histomorphometric analysis was performed for the evaluation of Bone Implant Contact, and Bone Ingrowth. A standard push-out test was used to analyze the mechanical characteristics of the bone-implant interface. The histomorphometric data and biomechanical tests showed a fast osseointegration of the specimens both in the cancellous and in the cortical bone. The quantitative analysis of osseointegration data in cancellous bone showed the percentage of the surface of the implant in direct contact with the regenerated bone matrix significantly improved from 28% at 6 weeks to 54% at 14 weeks. An early osseointegration occurred in cortical bone showing that 75% of surface of implant was in direct contact with regenerated bone after 6 weeks; this value increased to 85% after 14 weeks. Mechanical tests revealed an early improvement of mean peak load of implants at 10 weeks (4486 N ± 528 N) compared to values at 6 weeks (2516 N ± 910 N) confirming the high rate of progression of osseointegration in the cortical bone. The non-mineralized matrix followed an increasing process of mineralization almost completely after 14 weeks. The results of this study have showed a rapid osseointegration and excellent biocompatibility for a randomized trabecular titanium structure that should be confirmed by clinical investigations.

Periodontal regeneration is still a challenge for periodontists and tissue engineers, as it requires the simultaneous restoration of different tissues-namely, cementum, gingiva, bone, and periodontal ligament (PDL). Here, we synthetized a chitosan (CH)-based trilayer porous scaffold to achieve periodontal regeneration driven by multitissue simultaneous healing. We produced 2 porous compartments for bone and gingiva regeneration by cross-linking with genipin either medium molecular weight (MMW) or low molecular weight (LMW) CH and freeze-drying the resulting scaffolds. We synthetized a third compartment for PDL regeneration by CH electrochemical deposition; this allowed us to produce highly oriented microchannels of about 450-µm diameter intended to drive PDL fiber growth toward the dental root. In vitro characterization showed rapid equilibrium water content for MMW-CH and LMW-CH compartments (equilibrium water content after 5 min >85%). The MMW-CH compartment degraded more slowly and provided significantly more resistance to compression (28% ± 1% of weight loss at 4 wk; compression modulus HA = 18 ± 6 kPa) than the LMW-CH compartment (34% ± 1%; 7.7 ± 0.8 kPa) as required to match the physiologic healing rates of bone and gingiva and their mechanical properties. More than 90% of all human primary periodontal cell populations tested on the corresponding compartment survived during cytocompatibility tests, showing active cell metabolism in the alkaline phosphatase and collagen deposition assays. In vivo tests showed high biocompatibility in wild-type mice, tissue ingrowth, and vascularization within the scaffold. Using the periodontal ectopic model in nude mice, we preseeded scaffold compartments with human gingival fibroblasts, osteoblasts, and PDL fibroblasts and found a dense mineralized matrix within the MMW-CH region, with weakly mineralized deposits at the dentin interface. Together, these results support this resorbable trilayer scaffold as a promising candidate for periodontal regeneration.

Objective (i) To validate a simple and efficient method for extracting high quality RNA from small samples of bone tissue, (ii) to test its application on limited amounts of grafted oral bone and (iii) to analyze the gene expression of the OPG/RANK/RANKL system and IL-6 in “spontaneous healing” and grafted tissue. Design 26 patients in need of extraction of one lower molar tooth were divided in 3 groups. In group A (8 patients) the alveolar socket was left for spontaneous healing, in group B (8 patients) it was filled with a hydroxyapatite scaffold while in group C (10 patients) it was filled with hydroxyapatite granules. A small amount of bone was scraped from the alveolar site and sent for analysis. Four months later a new bone specimen was harvested during implant bed preparation. Results IL-6 increased over time in all groups and in particular to the grafted groups. RANK, RANKL and OPG increased over time in all groups, except for RANK in group B. The RANKL/OPG ratio showed a negative value in group A and even more in group B, while it was positive in group C. Conclusions The alveolar site grafted with a granular biomaterial behaved similar to the physiological healing group but displayed a slow remodeling process. RANK, RANKL, OPG and the RANKL/OPG ratio might be able to distinguish among different biomaterials and represent different healing patterns according to different clinical conditions.

Many chemical and physical modifications of titanium surfaces were introduced, aiming at improving surface bioactivity, but few comparative evidence exists.To evaluate histologically in minipigs the osseointegration of implants made of commercially pure (CP) titanium or titanium alloy, treated by different roughening procedures.Three sandblasted acid-etched (SA) surfaces, 2 anodized (AN), and 1 double acid-etched (DAE) were compared. Surface microtopography was characterized with scanning electron microscope; surface element composition was also assessed. One implant per group was inserted in each proximal tibia of 2 minipigs. Three months after healing, block biopsies were taken for histomorphometric analysis. Implant stability quotient (ISQ) was measured at insertion and before harvesting.The highest amount of cortical bone-implant contact was observed around SA implants and showed positive correlation with surface roughness. The greatest increase in ISQ was observed in CP-AN implants. In the medullary region, SA implants showed the best osteogenic response, whereas inflammatory cells were found around DAE and alloy-AN implants.SA surfaces were more osteogenic than anodized or dual acid-etched ones, although not significantly. Surface roughness affected osseointegration.

The aim of the study was to show in vitro the greater inertness to the corrosion body fluid of TiNbN coating than the CoCrMo alloy substrate. The prosthetic component under study was a femoral component of total knee prosthesis in CoCrMo alloy coated in TiNbN with Physical Vapor Deposition technique immersed in static Hank's balanced salt solution (HBS) (pH=6) for at least 34months at a constant temperature of 37 degrees C. Another uncoated prosthetic component of CoCrMo alloy with the same type and size was left in static immersion in the same solution and for the same period of time. Scanning electron microscope (SEM) analysis was performed to investigate adhesion and proliferation at 24, 48, 72h after seeding of 10(4) sub-confluents osteoblast-like cells (SaOS-2) cells on scaffold. The results of the study showed a reduction in the concentration of the metal ions released from the TiNbN-coated femoral component surface compared to the uncoated surface in the HBS solution. The overall reduction of the ions for the TiNbN-coated femoral component compared to the uncoated one was 80.1 +/- 2%, 62.5%+/- 8% and 48%+/- 10% for Co, Cr, Mo, respectively (p

OBJECTIVES Closing commercial, recreational and educational activities is one of the most frequently adopted measures worldwide, to respond to the COVID-19 pandemic Beyond their positive effect, however, such measures present negative economic, educational, and psychological aspects on the population To reduce these disadvantages, together with vaccines and therapies, it is crucial to develop efficient tools for early diagnosis and to rapidly interrupt the infective chain especially in particularly susceptible communities This dossier aims to provide an overview of the currently available diagnostic tests for SARS-CoV-2, with an insight in salivary molecular tests MATERIALS AND METHODS The present dossier reviews the currently available diagnostic tests for SARS-CoV-2 with a focus on salivary molecular tests, used within an experimental protocol by the UNIMI SAL research group of University degli Studi of Milan The dossier includes an overview of COVID-19 a narrative review of the literature and a paradigmatic case report that highlights the characteristics and potential use of the different available tests RESULTS The diagnostic SARS-CoV-2 tests can be classified according to the target they aim to detect, that is viral RNA, antigens or antibodies The currently official diagnostic tool is the naso-pharyngeal molecular swab, due to its high sensibility (>98%) and specificity (>99%) A farther tool is the antigenic swab, that, despite the advantage of a rapid result, is less accurate and whose positive result needs therefore to be confirmed by a naso-pharyngeal molecular swab Serological tests find their optimal application in epidemiological screenings concerning the anti- body status of individuals but are not strictly diagnostic reason why a positive outcome requires to be followed by a naso-pharyngeal molecular swab Serological tests find their optimal application in epidemiological screenings concerning the anti- body status of individuals but are not strictly diagnostic reason why a positive outcome requires to be followed by a naso-pharyngeal molecular swab Salivary molecular tests is under validation It is a non-invasive tool that can be self-performed and shows a high concordance with naso-pharyngeal molecular swabs Salivary molecular tests will be described in the context of an experimental protocol by the UNIMI SAL research group of University degli Studi of Milan Saliva collected by means of a dental cotton roll, was obtained in different settings both from adults and children, and its analysis provided promising results thanks to its high concordance with naso-pharyngeal molecular swabs and its ability to early detect positive asymptomatic and pre-symptomatic CONCLUSIONS The COVID-19 pandemic has prompted an increased request for new diagnostic and therapeutic possibilities in short times To implement research towards new and innovative tools useful to overcome the difficulties connected to closures and stay-at-home measures, is crucial In this context, salivary molecular tests seem to provide the adequate characteristics for active surveillance and early detection of positive cases CLINICAL SIGNIFICANCE Knowledge of different diagnostic tests and their applicability is fundamental for all health workers The comprehension of the different available devices and methods on the market for rapid and not rapid detection of SARS-CoV-2, is useful in the management of their daily clinical activity

Background and Overview Pyoderma gangrenosum (PG) is a rare neutrophil-mediated autoinflammatory dermatosis that can involve the oral mucosa. Dental surgery is a potential triggering factor for the onset of PG lesions. The authors describe and discuss the dental management of a rare case of aggressive periodontitis in a patient with PG, from multiple tooth extractions to prosthetic rehabilitation, including administration of systemic steroid prophylaxis before surgery to prevent the potential onset of PG-related lesions. Case Description A 22-year-old man who had a diagnosis of PG and who had aggressive periodontal disease underwent dental extractions, gingivoplastic surgery, and prosthetic rehabilitation. The patient received 8 milligrams of betamethasone intramuscularly 20 minutes before the oral surgery. The tissues healed perfectly, and no adverse effects were reported. Conclusions and Practical Implications For minor oral surgery, prophylactic corticosteroids might help reduce the risk of developing PG-related lesions. The clinician should plan the prosthetic devices to be as atraumatic as possible.

Background Tooth extraction generally results in an alveolar bone loss and structural changes in the overlying soft tissue. The amount of this relocation might jeopardize prosthetically driven implant placement. Thus, there is a high interest in techniques, materials and timing to minimizing tissue resorption, using postextraction ridge preservation procedures. Purpose To assess by histological techniques, the outcomes of a socket preservation technique at 4 or 12 months after treatment with a magnesium-enriched hydroxyapatite (Mg-e HA). Materials and Methods Postextraction site in 20 patients underwent ridge preservation procedure. Mg-e HA granules were mixed with blood and grafted into the socket. A bone specimen was collected from each site before implant placement after 4 or 12 months randomly. Each biopsy was processed for undecalcified histological analysis. All ground sections were observed under light and polarized microscope. A semi-quantitative analysis by mean of stereological method was performed to evaluate the average volume fractions of bone, biomaterial and medullary spaces, and the percentage of blood vessels for both timepoints. Nonparametric Mann–Whitney U test for unpaired data was used to detect eventual statistical differences between groups. Results Histologically, the biomaterial appeared surrounded by newly formed bone in both groups without inflammatory infiltrate. At 4 months, the remodeling process of collagen matrix was starting from the apical portion toward coronal direction and was more active around grafted particles. At 12 months, the alveolar socket was completely regenerated and filled with mineralized and well-organized bone tissue around the residual biomaterial particles. In both groups, vessels were present to supply tissues around the graft (at 4 months: 4.95% ± 2.49; at 12 months: 7.45% ± 2.57). Tissue fractions at 4 versus 12 months were respectively: 31.85% ± 6.99 versus 41.32% ± 9.37 for bone (p = .021), 40.82% ± 6.71 versus 26.28% ± 11.49 for residual Mg-e HA (p = .009), and 27.33% ± 7.72 versus 32.40% ± 9.87 for medullary spaces. Conclusion Data from the present study show that Mg-e HA allows the complete healing of the tissue. Additionally, graft material demonstrated to undergo significant resorption during the experimental time frame.

To evaluate the clinical and radiographic outcomes of a one-stage crestal sinus elevation procedure using a self-tapping endosseous implant system (iRaise, Maxillent, Herzliya, Israel) developed for sinus augmentation, 1 year after loading.Patients needing restoration in the posterior maxilla with a residual alveolar crest of 3 to 8 mm in height and 5 mm in width distal to the canine as measured on CBCT scan were treated using the iRaise sinus lift system. Outcome measures were: implant and prosthetic failures, any complications, increased bone height (iBH), marginal bone loss (MBL), implant stability quotient (ISQ), radiographic tissue remodelling patterns using the sinus grafting remodelling index (SGRI), volumetric measurements of sinus graft, patient self-reported post-surgical swelling, consumption of pain medication and histological analysis.A total of 30 consecutive participants with a mean age of 54.2 ± 9.4 years underwent a transcrestal elevation of the sinus membrane, insertion of bone graft, and implant placement. A total of 50 implants were placed (30 iRaise system implants and 20 adjunctive iSure implants, Maxillent). The mean follow-up was 15.8 ± 2.1 months after implant loading. One patient dropped out at the 1-year after loading follow-up examination. No implants and no prostheses failed during the entire follow-up. One patient experienced a small membrane tear. Before implant insertion, the mean residual alveolar ridge height was 4.64 ± 0.86 mm (range: 3.4-6.4 mm; 95% CI: 4.39-5.01 mm). One year after loading, the bone height was 16.86 ± 3.13 mm (95% CI 15.83-18.07 mm). At the 1-year after loading follow-up, the mean MBL was 0.19 ± 1.05 mm (95% CI 0.02-0.78 mm). The mean ISQ at implant placement was 65.2 ± 5.4 (95% CI 63.6-67.4) and increased during the healing period reaching the mean value of 73.6 ± 3.7 (95% CI 73.1-75.9; range 62-79). The difference was statistically significant (8.4 ± 5.3; 95% CI 5.9-39.7; P = 0.0000). One year after loading, SGRI score was evaluated in 23 implants. Overall, the mean SGRI value was 2.29 ± 2.41 mm (95% CI 1.22-2.98 mm). Bone volume at implant placement was 2.41 ± 0.25 CC (95% CI 2.22-2.48 CC). During the 6-month, submerged healing period, a slight bone contraction of 11.3% were observed. (2.13 ± 0.24 CC;95% CI 2.02-2.26; difference = 0.27 ± 0.25 CC; 95% CI 0.10-0.36; P = 0.0011). At the first year post-loading period, the bone graft remained stable (2.11 ± 0.22 CC; 95% CI 2.02-2.24). The difference was not statistically significant (0.02 ± 0.07 CC; 95% CI 0.01-0.04; P = 0.2166). From the patient's point of view, the mean pain value was 0.52 ± 0.74 (range 0-3); mean swelling value was 0.27 ± 0.52 (range 0-2); and the mean consumption of analgesic was 0.87 ± 4.94 tablets (range 0-4) 3 days after surgery. Morphological and histomorphometric analyses showed that all the samples had a normal structure without inflammatory infiltrate, six months after healing. The following fractions (%) were found: bone (immature bone + mature bone): 44.07 ± 4.91; residual biomaterial: 23.98 ± 2.64; medullary spaces: 31.95 ± 3.16.Sinus floor augmentation can be successfully accomplished with a transcrestal approach using a dedicated implant system. A physiologic contraction of 11.3% of the original volume of the bone graft was experienced during the first 6 months of healing; afterwards, no additional graft volume reduction was observed. Long-term clinical studies are needed to confirm these preliminary results.

Supernumerary teeth are teeth that exceed the normal dental formula. Their prevalence in the permanent dentition is 1–14% and they occur more frequently in maxilla with a sex ratio of 2 : 1 in favor of males. They are often associated with syndromes but there are examples of nonsyndromic multiple supernumerary teeth reported in the literature. CBCT is usually the best exam for radiographic diagnosis and treatment planning, because it provides 3D information about location and morphology of supernumerary teeth. This paper reports a rare case of four supernumerary teeth in a nonsyndromic 9-year-old boy. The peculiarity of this case is that two more exceeding teeth were found during surgical procedure. After extraction, all the teeth underwent a histological undecalcified processing for light microscopical examination. The two “ghost” supernumerary teeth seemed to be primordial dental germs, possibly resulting from an altered odontogenic process. After supernumerary teeth extraction, X-rays and exfoliation monitoring are recommended, since permanent retained teeth often erupt naturally or, at least, improve their condition. Radiographic follow-up is also useful in order to assess the formation of further teeth due to the hyperactivity of the dental lamina.

This study reports on the histologic characteristics of the early phases of implant osseointegration, focusing on osteopontin concentrations in the coronal area of implants placed with marginal defects and in control sites without defect preparation. In the mandibular right area of 12 dogs, two recipient sites were prepared and the margins were widened to obtain a gap of 0.5 mm at one site (small defect) and 1.25 mm at another site (large defect). Implants were placed and allowed a fully submerged healing. The procedure was subsequently performed in the left side in such a way as to obtain healing times of 5, 10, 20, and 30 days. Paraffin sections were stained with osteopontin antibodies and analyzed. At control implants, scarcely organized collagen fibers were observed in the space between the pristine bone and implant and were quickly replaced by mineralized tissue. In the small and large defects, the collagen fibers were organized in a layer that ran parallel to the implant at day 10 and became denser and thicker with time. Osteopontin was evenly distributed in the peri-implant tissue at control implants, while it was mainly located in the collagen bundle section around the implants placed in the defects.

Riassunto Obiettivi Descrivere i principali fattori di crescita e di differenziazione che intervengono nei processi di guarigione alveolare e analizzare le dinamiche biologiche che sono alla base dell’integrazione di un sostituto osseo. Il dossier prevede inoltre una sezione clinica esplicativa, nella quale vengono esaminati due diversi modelli di sperimentazione clinica nell’intento di documentare, in vivo, l’influenza dei materiali d’innesto sul pattern di rimodellamento osseo in un sito post-estrattivo. Materiali e metodi Per reperire materiale sull’argomento sono stati consultati testi di odontoiatria e chirurgia odontostomatologica, e banche dati scientifiche. Risultati e conclusioni Negli ultimi anni, le metodiche di preservazione alveolare basate sull’impiego di differenti innesti ossei “bone graft”, tra cui i biomateriali sintetici “alloplast”, hanno riscosso ampio successo in chirurgia odontoiatrica. I materiali riempitivi sintetici, infatti, grazie alla loro biocompatibilita e alla loro azione osteoconduttiva, trovano applicazione al fine di favorire la guarigione alveolare e preservare il volume, l’ampiezza e l’altezza della cresta edentula. Se da un lato appare chiaro il pattern di rimodellamento fisiologico a carico dell’alveolo in seguito alla perdita di un dente, dall’altro risulta poco comprensibile l’influenza di tali biomateriali a carico dei meccanismi di segnale coinvolti nel processo di rimodellamento nel sito d’innesto. La metodica immunoistochimica si rivela uno strumento molto utile nella valutazione, in vivo, degli effetti che diversi biomateriali determinano sul rimodellamento alveolare.

AIM: The first aim of the present experiment was to compare bone healing at implants installed in recipient sites prepared with conventional drills or a piezoelectric device. The second aim was to compare implant osseointegration onto surfaces with and without dendrimers coatings. MATERIAL AND METHODS: Six Beagles dogs were used in this study. Five implants with two different surfaces, three with a ZirTi(®) surface (zirconia sand blasted, acid etched), and two with a ZirTi(®)-modified surface with dendrimers of phosphoserine and polylysine were installed in the right side of the mandible. In the most anterior region (P2, P3), two recipient sites were prepared with drills, and one implant ZirTi(®) surface and one coated with dendrimers implants were installed at random. In the posterior region (P4 and M1), three recipient sites were randomly prepared: two sites with a Piezosurgery(®) instrument and one site with drill and two ZirTi(®) surface and one coated with dendrimers implants installed. Three months after the surgery, the animals were sacrificed for histological analysis. RESULTS: No complications occurred during the healing period. Three implants were found not integrated and were excluded from analysis. However, n = 6 was obtained. The distance IS-B at the buccal aspect was 2.2 ± 0.8 and 1.8 ± 0.5 mm, while IS-C was 1.5 ± 0.9 and 1.4 ± 0.6 mm at the Piezosurgery(®) and drill groups, respectively. Similar values were obtained between the dendrimers-coated and ZirTi(®) surface implants. The BIC% values were higher at the drill (72%) compared to the Piezosurgery(®) (67%) sites. The BIC% were also found to be higher at the ZirTi(®) (74%) compared to the dendrimers-coated (65%) implants, the difference being statistically significant. CONCLUSION: This study has revealed that oral implants may osseointegrate equally well irrespective of whether their bed was prepared utilizing conventional drills with abundant cooling or Piezosurgery(®). Moreover, the surface coating of implants with dendrimers phosphoserine and polylysine did not improve osseointegration.

The aim of this work was to compare histologically bone biopsies obtained during dental implant placement in atrophic jaws reconstructed with fresh-frozen bone (FFB) or autologous bone blocks.Twenty partially or totally edentulous patients were treated either with iliac crest FFB grafts (14 patients; group A) or with iliac crest autografts (6 patients; group B). Seven to 9 months later, dental implants were placed in the reconstructed jaws and bone biopsies were harvested.The reconstructive procedure was uneventful in 9 patients of group A and in all patients of group B. Samples from both groups did not show relevant differences concerning the proportion of lamellar bone, newly formed bone, and bone marrow. In group A, the decreasing proportion of blood vessels from the apical to the coronal portion, the larger amount of lacunae in the apical portion, and the fewer vessels in the coronal portion than in group B evoke an effort of the host bone to "integrate" the graft from the apical portion.FFB cannot be considered as successful and safe in alveolar bone reconstruction as autogenous bone grafting.

In the study, we assess a rapid prototyped scaffold composed of 30/70 hydroxyapatite (HA) and beta-tricalcium-phosphate (β-TCP) loaded with human adipose-derived stem cells (hASCs) to determine cell proliferation, differentiation toward osteogenic lineage, adhesion and penetration on/into the scaffold.In this in vitro study, hASCs isolated from fat tissue discarded after plastic surgery were expanded, characterized, and then loaded onto the scaffold. Cells were tested for: viability assay (Alamar Blue at days 3, 7 and Live/Dead at day 32), differentiation index (alkaline phosphatase activity at day 14), scaffold adhesion (standard error of the mean analysis at days 5 and 18), and penetration (ground sections at day 32).All the hASC populations displayed stemness markers and the ability to differentiate toward adipogenic and osteogenic lineages.Cellular vitality increased between 3 and 7 days, and no inhibitory effect by HA/β-TCP was observed. Under osteogenic stimuli, scaffold increased alkaline phosphatase activity of +243% compared with undifferentiated samples. Human adipose-derived stem cells adhered on HA/β-TCP surface through citoplasmatic extensions that occupied the macropores and built networks among them. Human adipose derived stem cells were observed in the core of HA/β-TCP. The current combination of hASCs and HA/β-TCP scaffold provided encouraging results. If authors' data will be confirmed in preclinical models, the present engineering approach could represent an interesting tool in treating large bone defects.

The most frequently-used histological parameters to define dental implant osseointegration include bone-to-implant contact and quantitative and qualitative assessments of the surrounding tissue (rate of mineralized/non-mineralized tissue and proportion of lamellar and woven bone compared to soft tissue or bone marrow). The aim of this paper was to present the histological features of the bone tissue surrounding three well-functioning Straumann SLA and SLActive implants placed in two patients after 12 and 60 months of loading. The percentage of osseointegration ranged from 66.4% and 71.9% for SLA surfaces, to 88.3% for the SLActive implant. Such results confirm that osseointegration occurs with high rates of bone-to-implant contact in humans, and that implants can be similarly clinically successful, although they show different bone-to-implant contact values.

Tooth extraction generally results in an alveolar bone loss and structural changes in the overlying soft tissue. The amount of this relocation might jeopardize prosthetically driven implant placement. Thus, there is a high interest in techniques, materials and timing to minimizing tissue resorption, using postextraction ridge preservation procedures.To assess by histological techniques, the outcomes of a socket preservation technique at 4 or 12 months after treatment with a magnesium-enriched hydroxyapatite (Mg-e HA).Postextraction site in 20 patients underwent ridge preservation procedure. Mg-e HA granules were mixed with blood and grafted into the socket. A bone specimen was collected from each site before implant placement after 4 or 12 months randomly. Each biopsy was processed for undecalcified histological analysis. All ground sections were observed under light and polarized microscope. A semi-quantitative analysis by mean of stereological method was performed to evaluate the average volume fractions of bone, biomaterial and medullary spaces, and the percentage of blood vessels for both timepoints. Nonparametric Mann-Whitney U test for unpaired data was used to detect eventual statistical differences between groups.Histologically, the biomaterial appeared surrounded by newly formed bone in both groups without inflammatory infiltrate. At 4 months, the remodeling process of collagen matrix was starting from the apical portion toward coronal direction and was more active around grafted particles. At 12 months, the alveolar socket was completely regenerated and filled with mineralized and well-organized bone tissue around the residual biomaterial particles. In both groups, vessels were present to supply tissues around the graft (at 4 months: 4.95% ± 2.49; at 12 months: 7.45% ± 2.57). Tissue fractions at 4 versus 12 months were respectively: 31.85% ± 6.99 versus 41.32% ± 9.37 for bone (p = .021), 40.82% ± 6.71 versus 26.28% ± 11.49 for residual Mg-e HA (p = .009), and 27.33% ± 7.72 versus 32.40% ± 9.87 for medullary spaces.Data from the present study show that Mg-e HA allows the complete healing of the tissue. Additionally, graft material demonstrated to undergo significant resorption during the experimental time frame.

Purpose: The aims of this study were to investigate the best two of five common methods of collecting autologous bone (preliminary study [PS]) and to test clinically the effects of autografts harvested using a trephine bur or bone scraper for sinus augmentation surgery (main study [MS]). Materials and Methods: In the PS, five autograft samples from five patients (n = 25) were harvested with a bone scraper, round bur, piezoelectric device, implant bur, and trephine bur and were processed for histomorphometric analysis. In the MS, sinus augmentation was performed on 20 patients using bovine-derived bone substitute and autograft collected with a trephine bur (group A, n = 10) or collected with a bone scraper (group B, n = 10). Narrow implants were also placed. At 6 months, changes in graft volume were evaluated with cone beam computed tomography. The amounts of regenerated bone, residual graft, and osseointegration of the implants were assessed histologically. Results: In the PS, the trephine bur and bone scraper harvested bone chips that were medium to large and more vital than those obtained with the other tools. In the MS, no significant differences were seen between groups in terms of the amount of residual biomaterial, regenerated bone, change in graft volume, and osseointegration. Conclusion: Biologic differences between these two bone particulates may not influence regeneration and implant osseointegration in sinus augmentation when mixed with xenograft bone.

The most frequently-used histological parameters to define dental implant osseointegration include bone-to-implant contact and quantitative and qualitative assessments of the surrounding tissue (rate of mineralized/non-mineralized tissue and proportion of lamellar and woven bone compared to soft tissue or bone marrow). The aim of this paper was to present the histological features of the bone tissue surrounding three well-functioning Straumann SLA and SLActive implants placed in two patients after 12 and 60 months of loading. The percentage of osseointegration ranged from 66.4% and 71.9% for SLA surfaces, to 88.3% for the SLActive implant. Such results confirm that osseointegration occurs with high rates of bone-to-implant contact in humans, and that implants can be similarly clinically successful, although they show different bone-to-implant contact values.

There is a lack of evidence in the literature on the correlation between histomorphometric findings and gene/protein expression markers for bone metabolism.Evaluation of the histological features, changes in protein expression and gene activation for specific markers of bone metabolism following application of the alveolar ridge preservation technique with magnesium-enriched hydroxyapatite (MgHA).For each patient (n=15), bone samples were harvested after tooth extraction and processed for immunohistochemical and gene expression analysis (T0). Then, all alveolar sockets were grafted with MgHA. After 4 months (T1), bone samples were harvested for histomorphometrical, immunohistochemical and gene expression analysis. Gene expression and protein expression were evaluated for: RANK, RANKL, OPG, IL-6, TNF-α.For all markers, gene expression increased, but not significantly, from T0 to T1. The mean RANKL/OPG ratio was 1.88±1.24. Protein expression increased significantly (p0.05) for TNF-α, IL-6, RANK and RANKL. Histomorphometrical features at T1 were not significantly related to protein expression at T0.After ridge preservation with MgHA, markers for bone catabolism were activated. No significant correlation was found between histomorphometrical features of the regenerated tissue and protein expression at baseline.