Resin-Bonded Prosthesis in Posterior Area to Prevent Early Marginal Bone Resorption in Implants Placed at Tissue Level

Aim: To evaluate the effect of the resin-bonded prosthesis (Maryland bridge) on marginal bone remodeling of implants placed at the tissue level in the posterior region. Methods: Consecutive healthy patients (n = 46) were included in this clinical study. Flapless not-submerged implants were placed with cover screws exposed and positioned approximately 0.5 mm above tissue level. Patients received the implant and a temporary resin-bonded prosthesis (RBP) (n = 22) or only the implant (n = 24). The RBPs were kept in place for 3 months and removed before impressions. The implants received a custom-made abutment and provisional resin crowns followed by definitive cemented metal-ceramic crowns after 2-3 weeks. The marginal bone level (MBL) was evaluated in a single-blind condition on scanned periapical radiographs and assessed mesially and distally (MBL-M/MBL-D). The bone levels of adjacent teeth (CEJ-M/CEJ-D) and the modification of the area between the implant and the mesial/distal teeth (Area-M/Area-D) were measured. All measurements were made at 1, 3 (pre-loading time) and 12 months (post-loading time). Linear regression models were fitted to evaluate the existence of any significant difference. Results: A total of 44 patients (20 Female, 24 Male; Mean age: 53.9 +/- 10.3) completed the study. Two patients were excluded for fractured RBP or de-bonding. The drop-out was of 4.3%. After 12 months, all implants were free from complications. No peri-implantitis or mucositis were observed. The RBP group showed the most stable MBL at 12 months (-0.07 +/- 0.41), statistically different from the non-RBP group (-0.67 +/- 0.52). CEJ-M and CEJ-D were stable in both groups. Conclusion: The proposed approach of the use of RBP creates a more stable marginal bone level around implants placed at the tissue level, resulting in a reliable technique to protect bone tissue from mechanical and occlusal trauma during the healing period and osteointegration

The Use of Premixed Calcium Silicate Bioceramic Sealer with Warm Carrier-Based Technique: A 2-Year Study for Patients Treated in a Master Program

Background: Recently several calcium silicate flowable sealers have been introduced as endodontic materials for the root canal. This clinical study tested the use of a new premixed calcium silicate bioceramic sealer in association with the Thermafil warm carrier-based technique (TF). Epoxy-resin-based sealer with the warm carrier-based technique was the control group. Methodology: Healthy consecutive patients (n = 85) requiring 94 root canal treatments were enrolled in this study and assigned to one filling group (Ceraseal-TF n = 47, AH Plus-TF n = 47) in accordance with operator training and best clinical practice. Periapical X-rays were taken preoperatively, after root canal filling and after 6, 12 and 24 months. Two evaluators blindly assessed the periapical index (PAI) and sealer extrusion in the groups (k = 0.90). Healing rate and survival rate were also evaluated. Chi-square tests was used to analyze significant differences between the groups. Multilevel analysis was performed to evaluate the factors associated with healing status. Results: A total of 89 root canal treatments in 82 patients were analyzed at the end-line (24 months). The total drop-out was 3.6% (3 patients; 5 teeth). A total of 91.1% of healed teeth (PAI 1-2) was observed in Ceraseal-TF, with 88.6% in AH Plus-TF. No significant difference was observed on healing outcome and survival among the two filling groups (p > 0.05). Apical extrusion of the sealers occurred in 17 cases (19.0%). Of these, 6 occurred in Ceraseal-TF (13.3%) and 11 in AH Plus-TF (25.0%). Three Ceraseal extrusions were radiographically undetectable after 24 months. All the AH Plus extrusions did not change during the evaluation time. Conclusions: The combined use of the carrier-based technique and premixed CaSi-based bioceramic sealer showed clinical results comparable with carrier-based technique and epoxy-resin-based sealer. The radiographical disappearance of apically extruded Ceraseal is a possible event in the first 24 months

The Influence of the Matrix on the Apatite-Forming Ability of Calcium Containing Polydimethylsiloxane-Based Cements for Endodontics

This study aimed to characterize the chemical properties and bioactivity of an endodontic sealer (GuttaFlow Bioseal) based on polydimethylsiloxane (PDMS) and containing a calcium bioglass as a doping agent. Commercial PDMS-based cement free from calcium bioglass (GuttaFlow 2 and RoekoSeal) were characterized for comparison as well as GuttaFlow 2 doped with dicalcium phosphate dihydrate, hydroxyapatite, or a tricalcium silicate-based cement. IR and Raman analyses were performed on fresh materials as well as after aging tests in Hank's Balanced Salt Solution (28 d, 37 degrees C). Under these conditions, the strengthening of the 970 cm(-1) Raman band and the appearance of the IR components at 1455-1414, 1015, 868, and 600-559 cm(-1) revealed the deposition of B-type carbonated apatite. The Raman I-970/I-638 and IR A(1010)/A(1258) ratios (markers of apatite-forming ability) showed that bioactivity decreased along with the series: GuttaFlow Bioseal > GuttaFlow 2 > RoekoSeal. The PDMS matrix played a relevant role in bioactivity; in GuttaFlow 2, the crosslinking degree was favorable for Ca2+ adsorption/complexation and the formation of a thin calcium phosphate layer. In the less crosslinked RoekoSeal, such processes did not occur. The doped cements showed bioactivity higher than GuttaFlow 2, suggesting that the particles of the mineralizing agents are spontaneously exposed on the cement surface, although the hydrophobicity of the PDMS matrix slowed down apatite deposition. Relevant properties in the endodontic practice (i.e., setting time, radiopacity, apatite-forming ability) were related to material composition and the crosslinking degree

Reciprocating System for Secondary Root Canal Treatment of Oval Canals: CBCT, X-rays for Remnant Detection and Their Identification with ESEM and EDX

Aim of the study: to evaluate root filling remnants after secondary root canal treatments (SRCTs) of oval-shaped canals with X-rays and cone beam computed tomography (CBCT). The SRCTs were performed using reciprocating NiTi instruments. Methods: Single-rooted teeth (N = 64) were randomly treated with Reciproc Blue (RB) and filled with AH Plus/single cone (SC group) or AH Plus/Guttafusion (GF group). After seven days of storage in HBSS (Hanks balanced salt solution), Gates Glidden burs #2/3 and RB #25 and #40 were used for the SRCTs. The time to complete the procedure was measured. X-rays and CBCT were used to calculate, respectively, the area and the volume occupied by the remnants in the coronal, middle, and apical thirds of each canal. Environmental scanning electron microscopy (ESEM) and energy dispersive X-ray spectroscopy (EDX) were used for qualitative evaluation and morphology composition of the remnants in sectioned roots. A statistical analysis was performed using Sigma Plot (version 13, IBM, Armonk, NY, USA). The study was designed according to PRILE guidelines. Results: After the SRCTs, the middle thirds of the root canals showed the presence of remnants in both groups, as demonstrated by X-rays and CBCT. The GF group showed a statistically significant higher volume of remnants than the SC Group only in the middle third. The ESEM supported by the EDX revealed the remnant composition by the detection of trace elements of sealer and gutta-percha in all root canals. Conclusion: The study demonstrated that the middle third of root canals is a critical region where remnants were packed and spread in the buccal-lingual sides of canals. ESEM-EDX detected a fine layer of filling remnants in all root thirds, suggesting a larger canal contamination than the X-rays and CBCT examinations revealed

The use of ESEM-EDX as an innovative tool to analyze the mineral structure of peri-implant human bone

This study aimed to investigate the mineralization and chemical composition of the bone-implant interface and peri-implant tissues on human histological samples using an environmental scanning electron microscope as well as energy-dispersive x-ray spectroscopy (ESEM-EDX) as an innovative method. Eight unloaded implants with marginal bone tissue were retrieved after four months from eight patients and were histologically processed and analyzed. Histological samples were observed under optical microscopy (OM) to identify the microarchitecture of the sample and bone morphology. Then, all samples were observed under ESEM-EDX from the coronal to the most apical portion of the implant at 500x magnification. A region of interest with bone tissue of size 750 7 500 microns was selected to correspond to the first coronal and the last apical thread (ROI). EDX microanalysis was used to assess the elemental composition of the bone tissue along the thread interface and the ROI. Atomic percentages of Ca, P, N, and Ti, and the Ca/N, P/N and Ca/P ratios were measured in the ROI. Four major bone mineralization areas were identified based on the different chemical composition and ratios of the ROI. Area 1: A well-defined area with low Ca/N, P/N, and Ca/P was identified as low-density bone. Area 2: A defined area with higher Ca/N, P/N, and Ca/P, identified as new bone tissue, or bone remodeling areas. Area 3: A well-defined area with high Ca/N, /P/N, and Ca/P ratios, identified as bone tissue or bone chips. Area 4: An area with high Ca/N, P/N, and Ca/P ratios, which was identified as mature old cortical bone. Bone Area 2 was the most represented area along the bone-implant interface, while Bone Area 4 was identified only at sites approximately 1.5 mm from the interface. All areas were identified around implant biopsies, creating a mosaic-shaped distribution with well-defined borders. ESEM-EDX in combination with OM allowed to perform a microchemical analysis and offered new important information on the organic and inorganic content of the bone tissue around implants

Mineral-doped poly(L-lactide) acid scaffolds enriched with exosomes improve osteogenic commitment of human adipose-derived mesenchymal stem cells

Exosomes derived from mesenchymal stem cells are extracellular vesicles released to facilitate cell communication and function. Recently, polylactic acid (PLA), calcium silicates (CaSi), and dicalcium phosphate dihydrate (DCPD) have been used to produce bioresorbable functional mineral-doped porous scaffolds-through thermally induced phase separation technique, as materials for bone regeneration. The aim of this study was to investigate the effect of mineral-doped PLA-based porous scaffolds enriched with exosome vesicles (EVs) on osteogenic commitment of human adipose mesenchymal stem cells (hAD-MSCs). Two different mineral-doped scaffolds were produced: PLA-10CaSi-10DCPD and PLA-5CaSi-5DCPD. Scaffolds surface micromorphology was investigated by ESEM-EDX before and after 28 days immersion in simulated body fluid (HBSS). Exosomes were deposited on the surface of the scaffolds and the effect of exosome-enriched scaffolds on osteogenic commitment of hAD-MSCs cultured in proximity of the scaffolds has been evaluated by real time PCR. In addition, the biocompatibility was evaluated by direct-contact seeding hAD-MSCs on scaffolds surface-using MTT viability test. In both formulations, ESEM showed pores similar in shape (circular and elliptic) and size (from 10\u201330 \ub5m diameter). The porosity of the scaffolds decreased after 28 days immersion in simulated body fluid. Mineral-doped scaffolds showed a dynamic surface and created a suitable bone-forming microenvironment. The presence of the mineral fillers increased the osteogenic commitment of hAD-MSCs. Exosomes were easily entrapped on the surface of the scaffolds and their presence improved gene expression of major markers of osteogenesis such as collagen type I, osteopontin, osteonectin, osteocalcin. The experimental scaffolds enriched with exosomes, in particular PLA-10CaSi-10DCPD, increased the osteogenic commitment of MSCs. In conclusion, the enrichment of bioresorbable functional scaffolds with exosomes is confirmed as a potential strategy to improve bone regeneration procedures

COVID-19 Vaccine Hesitancy in Italy: Predictors of Acceptance, Fence Sitting and Refusal of the COVID-19 Vaccination

Background: The hesitancy in taking the COVID-19 vaccine is a global challenge. The need to identify predictors of COVID-19 vaccine reluctance is critical. Our objectives were to evaluate sociodemographic, psychological, and behavioral factors, as well as attitudes and beliefs that influence COVID-19 vaccination hesitancy in the general population of Italy. Methods: A total of 2,015 people were assessed in two waves (March, April and May, 2021). Participants were divided into three groups: (1) individuals who accepted the vaccination (“accepters”); (2) individuals who refused the vaccination (“rejecters”); and (3) individuals who were uncertain about their attitudes toward the vaccination (“fence sitters”). Group comparisons were performed using ANOVA, the Kruskal-Wallis test and chi-square tests. The strength of the association between the groups and the participants' characteristics was analyzed using a series of multinomial logistic regression models with bootstrap internal validation (one for each factor). Results: The “fence sitters” group, when compared to the others, included individuals of younger age, lower educational level, and worsening economic situation in the previous 3 months. After controlling for sociodemographic factors, the following features emerged as the main risk factors for being “fence sitters” (compared with vaccine “accepters”): reporting lower levels of protective behaviors, trust in institutions and informational sources, frequency of use of informational sources, agreement with restrictions and higher conspirative mentality. Higher levels of COVID-19 perceived risk, trust in institutions and informational sources, frequency of use of informational sources, agreement with restrictions and protective behaviors were associated with a higher likelihood of becoming “fence sitters” rather than vaccine “rejecters.” Conclusions: The “fence sitters” profile revealed by this study is intriguing and should be the focus of public programmes aimed at improving adherence to the COVID-19 vaccination campaign

Oral Versus Standard Antimicrobial Treatment for Pyogenic Native Vertebral Osteomyelitis: A Single-Center, Retrospective, Propensity Score-Balanced Analysis

Background: Interest in shorter antimicrobial regimens and oral treatment for osteoarticular infections is growing. The aim of this study is to assess whether there is an association between the administration of an entirely oral antibiotic therapy (OT) and the clinical outcome of native vertebral osteomyelitis (NVOs). Methods: We conducted a single-center, retrospective, observational study on consecutive patients with pyogenic NVOs over a 10-year period (2008-2018). We performed multivariate logistic regression analysis to identify risk factors for clinical failure, both in the whole population and in subgroups. The impact of OT versus standard treatment (intravenous induction followed by oral treatment whenever possible) was assessed in patients with a non-multidrug-resistant microorganism (MDRO) etiology, and the impact of a rifampin-containing regimen was assessed in patients affected by NVOs caused by staphylococci or of unknown etiology. Results: The study population included 249 patients, and 33 (13.3%) experienced clinical failure; the OT group consisted of 54 patients (21.7%). Multivariate regression analysis of the whole population selected Charlson comorbidity index (adjusted odds ratio [aOR], 1.291; 95% confidence interval [CI], 1.114-1.497; P =. 001) and MDRO etiology (aOR, 3.301; 95% CI, 1.368-7.964; P =. 008) as independent factors for clinical failure. Among patients affected by a non-MDRO NVO, OT was not associated with an increased risk of clinical failure (aOR, 0.487; 95% CI,. 133-1.782; P =. 271), even after adjustment for the propensity score of receiving OT. In the subgroup of patients with staphylococcal or unknown etiology, NVO rifampin was independently associated with favorable outcome (aOR, 0.315; 95% CI,. 105-.949; P =. 040). Conclusions: An entirely oral, highly bioavailable treatment, including rifampin, may be as effective as parenteral treatment in selected patients with NVOs

PLA-based mineral-doped scaffolds seeded with human periapical cyst-derived MSCs: A promising tool for regenerative healing in dentistry

Human periapical cyst mesenchymal stem cells (hPCy-MSCs) are a newly discovered cell population innovatively collected from inflammatory periapical cysts. The use of this biological waste guarantees a source of stem cells without any impact on the surrounding healthy tissues, presenting a valuable potential in tissue engineering and regenerative medicine applications. In the present study, hPCy-MSCs were collected, isolated, and seeded on three experimental mineral-doped porous scaffolds produced by the thermally-induced phase-separation (TIPS) technique. Mineral-doped scaffolds, composed of polylactic acid (PLA), dicalcium phosphate dihydrate (DCPD), and/or hydraulic calcium silicate (CaSi), were produced by TIPS (PLA-10CaSi, PLA-5CaSi-5DCPD, PLA-10CaSi-10DCPD). Micro-CT analysis evaluated scaffolds micromorphology. Collected hPCy-MSCs, characterized by cytofluorimetry, were seeded on the scaffolds and tested for cell proliferation, cells viability, and gene expression for osteogenic and odontogenic differentiation (DMP-1, OSC, RUNX-2, HPRT). Micro-CT revealed an interconnected highly porous structure for all the scaffolds, similar total porosity with 99% open pores. Pore wall thickness increased with the percentage of CaSi and DCPD. Cells seeded on mineral-doped scaffolds showed a superior proliferation compared to pure PLA scaffolds (control), particularly on PLA-10CaSi-10DCPD at day 12. A higher number of non-viable (red stained) cells was observable on PLA scaffolds at days 14 and 21. DMP-1 expression increased in hPCy-MSCs cultured on all mineral-doped scaffolds, in particular on PLA-5CaSi-5DCPD and PLA-10CaSi-10DCPD. In conclusion, the innovative combination of experimental scaffolds colonized with autologous stem cells from periapical cyst represent a promising strategy for regenerative healing of periapical and alveolar bone

Assessment of DXA derived bone quality indexes and bone geometry parameters in early breast cancer patients: A single center cross-sectional study

Background: Bone mineral density (BMD) lacks sensitivity in individual fracture risk assessment in early breast cancer (EBC) patients treated with aromatase inhibitors (AIs). New dual-energy X-ray absorptiometry (DXA) based risk factors are needed. Methods: Trabecular bone score (TBS), bone strain index (BSI) and DXA parameters of bone geometry were evaluated in postmenopausal women diagnosed with EBC. The aim was to explore their association with morphometric vertebral fractures (VFs). Subjects were categorized in 3 groups in order to evaluate the impact of AIs and denosumab on bone geometry: AI-naive, AI-treated minus (AIDen-) or plus (AIDen+) denosumab. Results: A total of 610 EBC patients entered the study: 305 were AI-naive, 187 AIDen-, and 118 AIDen+. In the AI-naive group, the presence of VFs was associated with lower total hip BMD and T-score and higher femoral BSI. As regards as bone geometry parameters, AI-naive fractured patients reported a significant increase in femoral narrow neck (NN) endocortical width, femoral NN subperiosteal width, intertrochanteric buckling ratio (BR), intertrochanteric endocortical width, femoral shaft (FS) BR and endocortical width, as compared to non-fractured patients. Intertrochanteric BR and intertrochanteric cortical thickness significantly increased in the presence of VFs in AIDen- patients, not in AIDen+ ones. An increase in cross-sectional area and cross-sectional moment of inertia, both intertrochanteric and at FS, significantly correlated with VFs only in AIDen+. No association with VFs was found for either lumbar BSI or TBS in all groups. Conclusions: Bone geometry parameters are variably associated with VFs in EBC patients, either AI-naive or AI treated in combination with denosumab. These data suggest a tailored choice of fracture risk parameters in the 3 subgroups of EBC patients