Elucidating the Benefit of Perforated vs Non-Perforated Membranes in Guided Bone Regeneration: An in Vivo Histologic Evaluation and Histomorphometric Analysis.

Background: Non-perforated Polytetrafluoroethylene (PTFE) membranes are effectively utilized in guided bone regeneration (GBR) but may hinder cell migration due to limited interaction with the periosteum. This study compared bone regeneration using occlusive or perforated membranes combined with acellular collagen sponge (ACS) and recombinant human bone morphogenic protein-2 (rhBMP-2) in a canine mandibular model. Material and Methods: Male beagle dogs (n=3) received two mandibular defects each to compare ACS/rhBMP-2 with experimental (perforated group) and control (non-perforated group) membranes (n=3 defects/group). Tissue healing was assessed histomorphologically, histomorphometrically and through volumetric reconstruction using microcomputed tomography. Results: The perforated group showed increased bone formation and reduced soft tissue formation compared to the non-perforated group. For the primary outcome, histomorphometric analysis revealed significantly greater total regenerated bone in the perforated group (67.08 ± 6.86%) relative to the nonperforated group (25.18 ± 22.44%) (p = 0.036). Perforated membranes had less soft tissue infiltration (32.91 ± 6.86%) compared to non-perforated membranes (74.82 ± 22.44%) (p = 0.036). Conclusion: The increased permeability of membranes in the perforated group potentially enabled periosteal precursor cells greater accessibility to rhBMP-2. The availability may have accelerated their differentiation into mature bone-forming cells, contributing to the stimulation of new bone production, relative to the non-perforated group.

Oral Health Status and Factors Related to Oral Health in Patients with Schizophrenia: A Matched Case-Control Observational Study.

Background: Schizophrenia (SCZ) patients have disproportionately poor oral health outcomes owing to a multidimensional set of factors, such as pathophysiology of the disease, drug-related adverse effects and lower utilization rate of dental healthcare services. The aim of the present observational study was to compare the indicators of dental and periodontal health in patients with SCZ to those of nonaffected healthy controls; furthermore, the influence of various anamnestic factors and lifestyle habits on oral health status were also assessed. Methods: A total of 50 SCZ patients-in remission-receiving treatment at the Department of Psychiatry, University of Szeged, were compared with 50 age- and gender-matched healthy controls attending the Faculty of Dentistry, University of Szeged. Participants' dental (decayed, missing and filled surfaces [DMF-S] and decayed, missing and filled teeth [DMF-T]) and periodontal (plaque index [%], bleeding on probing [BOP%], pocket depth [PD] and attachment loss [AL]) status was measured according to the World Health Organization (WHO) criteria. Results: In total, 74.0%, 80.0% and 78.0% of SCZ patients received second-generation antipsychotics, benzodiazepines and mood stabilizers, respectively. Patients with SCZ had significantly higher DMFs (81.30 ± 40.16 vs. 61.64 ± 40.56; p = 0.010), D (8.18 ± 7.73 vs. 4.18 ± 4.22; p < 0.001) and DMF-T (18.20 ± 8.36 vs. 14.42 ± 8.21; p = 0.024) scores but significantly lower F (1.84 ± 0.29 vs. 4.62 ± 3.98; p < 0.001) scores compared to the controls; male subjects had significantly lower DMFs (74.52 ± 39.72 vs. 90.67 ± 39.1; p = 0.020) and DMF-T (16.52 ± 8.12 vs. 20.52 ± 8.32; p = 0.031) scores. Additionally, SCZ patients had significantly higher plaque indices (56.96 ± 23.19 vs. 27.44 ± 17.53; p < 0.001), BOP% (58.96 ± 22.89 vs. 23.56 ± 17.53; p < 0.001), PD (2.84 ± 0.67 vs. 2.19 ± 0.49; p = 0.024) and AL (3.39 ± 1.72 vs. 2.49 ± 0.76; p < 0.001) values compared to controls. Smoking > 10 cigarettes/day was associated with worse dental and periodontal indices, while consuming ≥ 4 units/week of alcohol was associated with worse periodontal indices, respectively (p < 0.05 in all cases). In contrast, coffee consumption rates and vitamin supplementation status had no significant effect on oral health status indicators. Conclusions: Our study highlights the overall poor oral health status of individuals affected by SCZ and the need for targeted preventive interventions.

Fracture strength of screw-retained zirconia crowns assembled on zirconia and titanium implants.

PURPOSE: This in vitro study evaluated the fracture strength of screw-retained zirconia crowns connected to zirconia (Zr) and titanium (Ti) implants after undergoing a simulation of 5 years of clinical use. MATERIALS AND METHODS: Forty-eight screw-retained zirconia crowns were fabricated and assembled on four implant systems, with 12 in each group: (1) Zr implant (pure ceramic; Straumann AG) (PZr); (2) Zr implant (NobelPearl; Nobel Biocare) (NPZr); (3) Ti-Zr implant (Bone Level Roxolid; Straumann AG) (RSTiZr); (4) Ti implant (Conical Connection PMC; Nobel Biocare) (NRTi). Crowns were luted to their associated abutments using resin cement and then torqued to their assigned implants at the recommended torque value. Specimens were subjected to dynamic loading for 1,200,000 loading cycles. Fracture strength, measured in Newtons (N), was tested under static compression load using a universal testing machine at an angle of 30°. One-way ANOVA and Tukey's multiple comparisons post hoc test were used to compare the mean fracture values between the groups at a significance level of 0.05. RESULTS: The average fracture strengths for the RSTiZr and NRTi groups were 1207 ± 202 and 1073 ± 217 N, respectively, which was significantly (p < 0.0001) higher than the PZr and NPZr groups (712 ± 76 and 571.6 ± 167 N, respectively). However, no significant difference was found between the fracture strength value of RSTiZr and NRTi (p = 0.260) or PZr and NPZr (p = 0.256) groups. CONCLUSIONS: Zirconia crowns connected to Zr implants have the potential to withstand the average physiological occlusal forces which occur in the anterior and premolar regions.

Accuracy of intraoral optical scan versus stereophotogrammetry for complete-arch digital implant impression: An in vitro study.

PURPOSE: To assess and compare the accuracies of intraoral scanners (IOS) and stereophotogrammetry (SPG) devices for complete-arch digital implant impressions. METHODS: A 4-analog model was digitized using a desk scanner to obtain a reference file. Thirty test scans were conducted using the investigated IOS device, while an additional 30 scans were performed using the SPG device. Using the best-fit algorithm, the resulting 60 test files were aligned with the reference file. Linear (ΔX, ΔY, and ΔZ-axis) and angular deviations (ΔANGLE) were evaluated. Three-dimensional (3D) deviation was calculated based on the Euclidean distance (ΔEUC). The analysis was stratified according to the scanning device and implant position. Fisher's F and t-tests were used to compare the variances and expected values of the two scanning systems. RESULTS: IOS expressed a higher 3D (ΔEUC) mean deviation than SPG (52.8 µm vs. 33.4 µm, P < 0.0001), with extreme measurements up to 181.9 µm. A significantly higher standard deviation (SD) was associated with IOS (37.1 µm vs. 17.7 µm, P < 0.0001). Considering angular deviations, the IOS showed slightly higher angular mean deviations (ΔANGLE) than the SPG (0.28° vs. 0.24°, P = 0.0022), with extreme measurements of up to 0.73°. The SPG SD values were significantly lower than the IOS SD values (0.14° vs. 0.04°, P < 0.0001). CONCLUSIONS: The SPG showed significantly higher 3D and angular accuracies for complete arch implant impressions, with consistent repeatability. IOS scanning revealed significantly higher extreme deviations exceeding the acceptable threshold value. Despite study limitations, SPG appears more feasible than IOS for complete-arch digital implant impressions.

UPLC-ESI-QTOF-MS assisted targeted metabolomics to study the enrichment of vinca alkaloids and related metabolites in Catharanthus roseus plants grown under controlled LED environment.

Enrichment of pharmaceutically important vinca alkaloids, vinblastine and vincristine, in the leaves of Madagascar periwinkle (Catharanthus roseus) plants through different pre- or postharvest treatments or cultivation conditions, e.g., exposing the plants to UV-irradiation, has been in focus for decades. Controlled LED environment in the visible light range offers the possibility of monitoring the changes in the concentration of metabolites in the vinca alkaloid-related pathway without involving UV-related abiotic stress. In the frame of our targeted metabolomics approach, 64 vinca alkaloids and metabolites were screened with the help of a UPLC-ESI-QTOF-MS instrumental setup from the leaf extracts of C. roseus plants grown in chambers under control (medium light), low light, and high blue / high red/ high far-red conditions. Out of the 14 metabolites that could be assigned either unambiguously with authentic standards or tentatively with high resolution mass spectrometry-based methods, all three dimer vinca alkaloids, that is, 3',4'-anhydrovinblastine, vinblastine and vincristine showed an at least nine-fold enrichment under high blue irradiation when compared with the control conditions: final concentrations of 961 mg kg-1 dry weight, 33.8 mg kg-1 dry weight, and 11.7 mg kg-1 dry weight could be achieved, respectively. As supported by multivariate statistical analysis, the key metabolites of the vinca alkaloid pathway were highly represented among the metabolites that were specifically stimulated by high blue light application.

Accuracy of complete-arch digital implant impression with intraoral optical scanning and stereophotogrammetry: An in vivo prospective comparative study.

OBJECTIVES: To assess accuracy of intraoral optical scanning (IOS) and stereophotogrammetry (SPG), complete-arch digital implant impressions in vivo. MATERIALS AND METHODS: Consecutive patients needing implant-supported screw-retained zirconia complete-arch fixed-dental prostheses (ISZ-FDP) were recruited. For each patient, three impressions were taken: IOS, SPG (tests), and open-tray plaster (reference). Linear (ΔX, ΔY, and ΔZ), three-dimensional (ΔEUC), and angular deviations (ΔANGLE) were evaluated and stratified according to scanning technology for each implant. Potential effects of impression device (IOS and SPG), arch (maxilla and mandible), and implant number (4 and 6) were evaluated through multivariable analysis. Significance level was set at .05. RESULTS: A total of 11 complete arches (5 maxillae, 6 mandibles) in 11 patients were rehabilitated with ISZ-FDPs supported by 4 (n = 8) and 6 implants (n = 3). A total of 50 implants and 100 implant positions were captured by two investigated devices and compared to respective reference (mean ΔEUC IOS 137.2, SPG 87.6 µm; mean ΔANGLE 0.79, 0.38°). Differences between measurements (SPG-IOS) were computed for each implant, with negative values indicating better SPG accuracy. Significant mean ΔEUC difference of -49.60 µm (p = .0143; SD 138.15) and mean ΔANGLE difference of -0.40° (p < .0001; SD 0.65) were observed in favor of SPG. Multivariable analysis showed significant effect on ΔEUC (p = .0162) and ΔANGLE (p = .0001) only for impression devices, with SPG performing better. CONCLUSIONS: SPG experienced significantly higher linear and angular accuracy. No effect of type of arch or implant number was detected. Higher extreme deviations were experienced for IOS. SPG can be feasible for complete-arch digital impressions with caution, and rigid prototype try-in is recommended before screw-retained prosthesis manufacturing.

Histological evaluation following treatment of recession-type defects with coronally advanced flap and a novel human recombinant amelogenin.

OBJECTIVES: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects. MATERIALS AND METHODS: A total of 17 gingival recession-type defects were surgically created in the maxilla of three minipigs. The defects were randomly treated with a coronally advanced flap (CAF) and either rAmelX (test), or a CAF and placebo (control). At three months following reconstructive surgery, the animals were euthanized, and the healing outcomes histologically evaluated. RESULTS: The test group yielded statistically significantly (p = 0.047) greater formation of cementum with inserting collagen fibers compared with the control group (i.e., 4.38 mm ± 0.36 mm vs. 3.48 mm ± 1.13 mm). Bone formation measured 2.15 mm ± 0.8 mm in the test group and 2.24 mm ± 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94). CONCLUSIONS: The present data have provided for the first-time evidence for the potential of rAmelX to promote regeneration of periodontal ligament and root cementum in recession-type defects, thus warranting further preclinical and clinical testing. CLINICAL RELEVANCE: The present results set the basis for the potential clinical application of rAmelX in reconstructive periodontal surgery.

Healing of intrabony defects using a novel human recombinant amelogenin: a preclinical study.

OBJECTIVE: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects. METHOD AND MATERIALS: Intrabony defects were surgically created in the mandible of three minipigs. Twelve defects were randomly treated with either rAmelX and carrier (test group) or with the carrier only (control group). At 3 months following reconstructive surgery, the animals were euthanized, and the tissues histologically processed. Thereafter, descriptive histology, histometry, and statistical analyses were performed. RESULTS: Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (eg, suppuration, abscess formation, unusual inflammatory reaction) were observed with a good biocompatibility of the tested products. The test group yielded higher values for new cementum formation (4.81 ± 1.17 mm) compared to the control group (4.39 ± 1.71 mm) without reaching statistical significance (P = .937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, P = .309). CONCLUSIONS: The present results provided for the first-time histologic evidence for periodontal regeneration following the use of rAmelX in intrabony defects, thus pointing to the potential of this novel recombinant amelogenin as a possible alternative to regenerative materials from animal origins.

Effects of Health Anxiety, Social Support, and Coping on Dissociation with Mediating Role of Perceived Stress during the COVID-19 Pandemic.

BACKGROUND: Our study aimed to examine whether health anxiety, social support, and ways of coping relate to dissociation directly or only through the mediation of perceived stress, moderated by the time of measurement (lockdown). We investigated the effect of perceived stress on different forms (sub-scales) of dissociation. METHODS: A cross-sectional survey was conducted by an online form at two points in time: the beginning and the later stage of the COVID-19 pandemic. RESULTS: We received a total of 1711 responses. Perceived stress moderately correlated with dissociation in both international and Hungarian samples. Health anxiety showed a strong direct and indirect correlation with dissociation. Regarding social support, the support of family significantly decreased the dissociative experiences in the Hungarian sample mediated by perceived and direct stress. In the international sample, goal-oriented coping strategies strongly decreased all dissociation scales in the first measurement, through the mediation of perceived stress. As for the Hungarian sample, positive thinking was found to decrease dissociation by decreasing perceived stress. CONCLUSION: health anxiety, coping, and social support appeared to influence dissociation directly and through the mediation of perceived stress. Social support, mainly support of the family and problem-focused coping strategies may decrease the level of stress, this way decreasing dissociative behavior.

Context-Dependent Role of Glucocorticoid Receptor Alpha and Beta in Breast Cancer Cell Behaviour.

Background. The dual role of GCs has been observed in breast cancer; however, due to many concomitant factors, GR action in cancer biology is still ambiguous. In this study, we aimed to unravel the context-dependent action of GR in breast cancer. Methods. GR expression was characterized in multiple cohorts: (1) 24,256 breast cancer specimens on the RNA level, 220 samples on the protein level and correlated with clinicopathological data; (2) oestrogen receptor (ER)-positive and -negative cell lines were used to test for the presence of ER and ligand, and the effect of the GRß isoform following GRα and GRß overexpression on GR action, by in vitro functional assays. Results. We found that GR expression was higher in ER- breast cancer cells compared to ER+ ones, and GR-transactivated genes were implicated mainly in cell migration. Immunohistochemistry showed mostly cytoplasmic but heterogenous staining irrespective of ER status. GRα increased cell proliferation, viability, and the migration of ER- cells. GRß had a similar effect on breast cancer cell viability, proliferation, and migration. However, the GRß isoform had the opposite effect depending on the presence of ER: an increased dead cell ratio was found in ER+ breast cancer cells compared to ER- ones. Interestingly, GRα and GRß action did not depend on the presence of the ligand, suggesting the role of the "intrinsic", ligand-independent action of GR in breast cancer. Conclusions. Staining differences using different GR antibodies may be the reason behind controversial findings in the literature regarding the expression of GR protein and clinicopathological data. Therefore, caution in the interpretation of immunohistochemistry should be applied. By dissecting the effects of GRα and GRß, we found that the presence of the GR in the context of ER had a different effect on cancer cell behaviour, but independently of ligand availability. Additionally, GR-transactivated genes are mostly involved in cell migration, which raises GR's importance in disease progression.

The root submergence technique at single tooth sites to short-span edentulous sites: A step-by-step partial extraction therapy protocol.

Submerging roots for ridge preservation was the earliest partial extraction therapy and has been described since the 1970s. Despite the approximately 47 animal and human studies published since, an updated and contemporary step-by-step protocol has not yet been provided. This technique report describes in detail how to manage submerged roots at single tooth sites and at short-span edentulous areas.

Root submergence technique as a partial extraction therapy to preserve the alveolar ridge tissues: A systematic review and appraisal of the literature.

STATEMENT OF PROBLEM: As socket grafting with commercially available biomaterials has become popular, reports of the root submergence technique for ridge preservation have decreased. A systematic review of this partial extraction therapy is lacking. PURPOSE: The purpose of this systematic review was to review the root submergence technique as well as critically appraise the available data. MATERIAL AND METHODS: A review was carried out that observed the Participant, Intervention, Comparison, Outcomes (PICO) strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The focused question was "What are the outcomes of the different methods to submerge tooth roots for ridge preservation?" Medical subject headings (MeSH) terms that related to the root submergence technique were searched in PubMed/MEDLINE, Scopus, and the Cochrane Library databases. RESULTS: A total of 7709 abstracts and study titles were individually screened from the initial search results. After reviewing the full-text articles and applying the selection criteria, the final included search results totaled 47 full-text articles for in-depth review. In 10 animal studies, 258 roots were studied in 34 dogs and 7 monkeys. Histological data confirmed that coronal bridging (bone or cementum growth over the cut root) was a common outcome. Of the vital roots submerged, the majority maintained their vitality. In 37 human studies, 475 roots were submerged and reported on. Subjective ridge preservation was often reported. Among the adverse healing outcomes, exposure of the root through the mucosa was the most common. Nonetheless, in animals, 86.8% of roots remained submerged; in humans, 74.7%. CONCLUSIONS: Root submergence is an established technique for ridge preservation. Exposure is a common complication, and correct technique may be key to its prevention. Further research of this partial extraction therapy is encouraged.

Effects of Hydroxypropyl-Beta-Cyclodextrin on Cultured Brain Endothelial Cells.

The application of 2-hydroxypropyl-beta-cyclodextrin (HPBCD) in the treatment of the rare cholesterol and lipid storage disorder Niemann-Pick disease type C opened new perspectives in the development of an efficient therapy. Even if the systemic administration of HPBCD was found to be effective, its low permeability across the blood-brain barrier (BBB) limited the positive neurological effects. Nevertheless, the cellular interactions of HPBCD with brain capillary endothelial cells have not been investigated in detail. In this study, the cytotoxicity, permeability, and cellular internalization of HPBCD on primary rat and immortalized human (hCMEC/D3) brain capillary endothelial cells were investigated. HPBCD shows no cytotoxicity on endothelial cells up to 100 µM, measured by impedance kinetics. Using a fluorescent derivative of HPBCD (FITC-HPBCD) the permeability measurements reveal that on an in vitro triple co-culture BBB model, FITC-HPBCD has low permeability, 0.50 × 10-6 cm/s, while on hCMEC/D3 cell layers, the permeability is higher, 1.86 × 10-5 cm/s. FITC-HPBCD enters brain capillary endothelial cells, is detected in cytoplasmic vesicles and rarely localized in lysosomes. The cellular internalization of HPBCD at the BBB can help to develop new strategies for improved HPBCD effects after systemic administration.

Automatic bone segmentation for oral surgical planning / Automatikus csontszegmentáció szájsebészeti mutéti tervezés támogatására

Introduction: Evolvement of digital technology encouraged the use of virtual dental and dental surgical planning and navigated surgery. The variety of cases is significant, therefore even for an expert, it is challanging to recover a traumatic case, or to design and apply implants with high anatomical precision. Objective: High-quality image acquisition and processing are essential to the process. CT (computer tomography) or CBCT (cone-beam computer tomography) images having bad initial quality greatly decrease the performance of the processing algorithms and affect the quality of the reconstructed 3D models. 3D reconstruction using manual segmentation takes several hours of work and expertise, which significantly increases the overall cost and time of 3D CAD/CAM (computer-aided design/computer-aided manufacturing) based surgical planning and production processes. Material and method: In this paper, we introduce a bone segmentation algorithm specifically designed for surgical planning, and evaluate its benefits for the aforementioned goal. The approach relies on edge detection, mathematical morphology and basic image-processing operations. Results: Performance has been evaluated on 40 series of manual segmentation. Results (precision 90%) show that the algorithm is fast and accurate so it is applicable for surgical planning. Conclusion: Our algorithm significantly reduces the execution time of segmentation and surgical planning, therefore increases the efficiency of the overall procedure.

Cellular Effects of Cyclodextrins: Studies on HeLa Cells.

Cyclodextrins are high molecular weight, hydrophilic, cyclic, non-reducing oligosaccharides, applied as excipients for the improvement of the solubility and permeability of insoluble active pharmaceutical ingredients. On the other hand, beta-cyclodextrins are used as cholesterol sequestering agents in life sciences. Recently, we demonstrated the cellular internalization and intracellular effects of cyclodextrins on Caco-2 cells. In this study, we aimed to further investigate the endocytosis of (2-hydroxylpropyl)-beta-(HPBCD) and random methylated-beta-cyclodextrin (RAMEB) to test their cytotoxicity, NF-kappa B pathway induction, autophagy, and lysosome formation on HeLa cells. These derivatives were able to enter the cells; however, major differences were revealed in the inhibition of their endocytosis compared to Caco-2 cells. NF-kappa B p65 translocation was not detected in the cell nuclei after HPBCD or RAMEB pre-treatment and cyclodextrin treatment did not enhance the formation of autophagosomes. These cyclodextrin derivates were partially localized in lysosomes after internalization.

Discrepancies between clinical and autopsy findings in patients who had an acute stroke.

OBJECTIVES: According to international observations, the incidence of clinical autopsies is declining worldwide, plummeting below 5% in the USA and many European countries. It is an unfavourable trend as, in 7%-12% of cases, recent clinicopathological studies found discrepancies that might have changed the therapy or the outcome if known premortem. As previous large-scale observations have examined varied patient populations, we aimed to focus on the differences between the clinical and pathological diagnostic findings in only patients who had a stroke. MATERIAL AND METHODS: We assessed the postmortem non-neuropathological and neuropathological findings of 534 consecutive patients who had a stroke who passed away. Systemic neoplasms, pneumonias, thromboembolisms and haemorrhagic transformations revealed only by autopsy were considered severe abnormalities; in addition, benign abnormalities important from an educational or scientific point of view were also recorded. RESULTS: In 26 of the 534 cases (4.9%), the presence of systemic neoplasms had already been confirmed in the clinical stage; however, 8 (1.5%) malignant tumours were only detected during autopsy. Also, 80 (15%) thromboembolic events, 73 (13.6%) pneumonias and 66 (18%) haemorrhagic transformations were only diagnosed at autopsy. Longer hospital stay (from admission to death) resulted in fewer discrepancies between clinical and autopsy diagnosis of thromboembolic events and pneumonias (p<0.01). In 169 cases, benign findings were detected. CONCLUSIONS: While the type of acute stroke is reliably diagnosed with imaging techniques, postmortem autopsies are also important in patients who had a stroke as autopsies may reveal clinically silent diseases (eg, tumour), and contribute to knowing the actual incidence of stroke-related thromboembolic and pneumonia complications.

Revealing Distress and Perceived Stress among Dentists at the Outset of the COVID-19 Pandemic: A Cross-Sectional Factor Analytic Study.

Dentists' perceptions about the stressfulness of clinical practice are well-documented, but literature on perceived stress and psychological distress experienced during the COVID-19 pandemic is scarce. This study aims to explore the emotions and attitudes, and the socio-demographic, dental, and COVID-related factors that are associated with the emergence of perceived stress and psychological distress that have been experienced by dentists during the COVID-19 pandemic. General demographic and dental-related data, and specific questions measuring the potential factors regarding dental professionals' concerns and opinions about their professional circumstances during the pandemic, were electronically collected from 182 dental practitioners. Exploratory and confirmatory factor analyses were used to assess whether dentists' emotions and attitudes during the pandemic measure the same construct: psychological distress, while linear regression models were built on the exploration of the effects of COVID-related factors on perceived stress and psychological distress. Facets of impulsiveness, lack of interest in social connections, emotional disengagement, mood swings, and acknowledgment of emotional exhaustion due to the pandemic, were measurements of the same construct and manifested in a singular factor: psychological distress. Two aspects, the fear of aerosol propagation and insecurities of financial status, increased the likelihood of the emergence of heightened levels of perceived stress and distress, while years spent in dental practice and age seemed to be protective factors against perceived stress and distress.

3D Considerations and Outcomes of Immediate Single Implant Insertion and Provisionalization at the Maxillary Esthetic Zone: A Long-Term Retrospective Follow-Up Study of Up to 18 Years.

AIM: Long-term studies addressing the outcomes of single immediate implantation and provisionalization at the maxillary esthetic zone are needed. The current study aimed to assess such outcomes along a follow-up period of up to 18 years. MATERIALS AND METHODS: The current study is a continuation follow-up of our previously published up to 6-year follow-up study, dated between the years 2002-2008, performed in a private clinical practice in Tel-Aviv, Israel. A total of 15 patients (23 implants) who had been treated for single-tooth replacement at the maxillary esthetic zone since 2002, underwent clinical and radiographic follow-up evaluations. Primary outcomes included mean Marginal Bone Levels (MBL), with Bleeding on Probing (BOP), implant success rate, prosthetic and esthetic complications evaluated as secondary outcomes. RESULTS: The implant success rate was at 100%. Bone remodeling processes were observed over the follow-up period, with 0.9 mm mean marginal bone loss observed during the first 6 years of observation, followed by -0.13 ± 0.06 mm mean loss after 6 to 18 years. The last finding suggests bone deposition, as reported by other studies (Donati et al., 2012). At the final radiographic evaluation, a mean MBL of 1.35 mm ± 0.16 was demonstrated. No differences with respect to implant type or site were found. A generalized absence of BOP and esthetic complications occurred in two cases as a result of continuous adjacent teeth eruption versus obvious implant ankylosis. CONCLUSIONS: Adhering to careful clinical protocols and 3D bone to implant considerations while immediately placing an anterior implant, this treatment approach offers both stable and esthetically acceptable results for the replacement of missing teeth at the maxillary esthetic zone.

Trueness and precision of 3D-printed versus milled monolithic zirconia crowns: An in vitro study.

PURPOSE: To compare the trueness and precision of 3D-printed versus milled monolithic zirconia crowns (MZCs). METHODS: A model of a maxilla with a prepared premolar was scanned with an industrial scanner (ATOSQ®, Gom) and an MZC was designed in computer-assisted-design (CAD) software (DentalCad®, Exocad). From that standard tessellation language (STL) file, 10 MZCs (test) were 3D-printed with a Lithography-based Ceramic Manufacturing (LCM) printer (CerafabS65®, Lithoz) and 10 MZCs (control) were milled using a 5-axis machine (DWX-52D®, DGShape). All MZCs were sintered and scanned with the aforementioned scanner. The surface data of each sample (overall crown, marginal area, occlusal surface) were superimposed to the original CAD file (ControlX®, Geomagic) to evaluate trueness: (90-10)/2, absolute average (ABS AVG) and root mean square (RMS) values were obtained for test and control groups (MathLab®, Mathworks) and used for analysis. Finally, the clinical precision (marginal adaptation, interproximal contacts) of test and control MZCs was investigated on a split-cast model printed (Solflex350®, Voco) from the CAD project, and compared. RESULTS: The milled MZCs had a significantly higher trueness than the 3D-printed ones, overall [(90-10)/2 printed 37.8 µm vs milled 21.2 µm; ABS AVG printed 27.2 µm vs milled 15.1 µm; RMS printed 33.2 µm vs milled 20.5 µm; p = 0.000005], at the margins [(90-10)/2 printed 25.6 µm vs milled 12.4 µm; ABS AVG printed 17.8 µm vs milled 9.4 µm; RMS printed 22.8 µm vs milled 15.6 µm; p= 0.000011] and at the occlusal level [(90-10)/2 printed 50.4 µm vs milled 21.9 µm; ABS AVG printed 29.6 µm vs milled 14.7 µm; RMS printed 38.9 µm vs milled 22.5 µm; p = 0.000005]. However, with regard to precision, both test and control groups scored highly, with no significant difference either in the quality of interproximal contact points (p = 0.355) or marginal closure (p = 0.355). CONCLUSIONS: Milled MZCs had a statistically higher trueness than 3D-printed ones; all crowns, however, showed high precision, compatible with the clinical use. CLINICAL SIGNIFICANCE: Although milled MZCs remain more accurate than 3D-printed ones, the LCM technique seems able to guarantee the production of clinically precise zirconia crowns.

Non-invasive smooth muscle electromyography (SMEMG) as a novel monitoring technology of the gastrointestinal tract of awake, free-moving pigs-A pilot study.

There are several mathematical models and measurements to determine the efficiency of the digestibility of different feedstuffs. However, there is lack of information regarding the direct methods or measurement techniques used to analyse the physical response of the different parts of the gastrointestinal tract (GIT) of growing pigs to different diets. Smooth muscle electromyography (SMEMG) is a non-invasive method for the measurement of gastrointestinal myoelectrical activity. In the present study, SMEMG methodology has been adapted from laboratory rats to pigs, and the effects of feedstuffs with control (CTR) or experimentally increased (EXP) amounts of fibre were investigated on gastrointestinal tract motility. Nine barrow pigs ((Danish Landrace × Danish Yorkshire) × Danish Duroc) were used (30 ± 3 kg), and their CTR and EXP feedstuffs contained 29 and 49 g/kg crude fibre (CF), respectively. Myoelectric activities of the stomach, ileum and caecum were detected in the awake pigs by a pair of electrodes. The recorded myoelectric signals were analysed with fast Fourier transformation (FFT), and the spectra were expressed in GIT section-specific cycles per minutes (cpm) values and the maximum power spectrum density (PsDmax). A significant increase (P < 0.001) was observed in the value of the PsDmax of the small intestine (20-25 cpm) as a consequence of the EXP diet. The PsDmax values of the stomach (3-5 cpm) and large intestine (1-3 cpm) did not show any significant change in pigs fed the EXP diet. As a direct and non-invasive method, SMEMG is suitable for the rapid evaluation of the effects of diets with different fibre contents on the GIT of non-anaesthetised, free-moving pigs.