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Aim: To evaluate the effect of systemic administration of propranolol on the severity of apical periodontitis (AP) in chronically stressed rats. Methodology: Twenty‐four 70‐day‐old male Wistar rats (Rattus norvegicus, albinus) were distributed into three groups (n = 8): rats with AP without stressful conditions (AP‐Control), rats with AP and submitted to a chronic unpredictable stress (CUS) protocol (AP + S) and rats with AP and submitted to a CUS protocol treated with propranolol (AP + S + PRO). Stress procedures were applied daily until the end of the experiment. After 3 weeks of CUS, AP was induced in all groups by exposing the pulpal tissue of mandibular and maxillary first molars to the oral environment. Propranolol treatment was administered orally once a day for the entire period of the experiment. Rats were sacrificed at 42 days, and the blood was collected for stress biomarkers serum dosage by multiplex assay. Mandibles were removed and submitted to microtomography and histopathological analyses. Periapical tissue surrounding the upper first molar was homogenized and subjected to RT‐PCR analysis to evaluate the mRNA expression of RANKL, TRAP and OPG. Parametric data were assessed using one‐way ANOVA followed by Tukey's test while the nonparametric data were analysed by the Kruskal–Wallis followed by Dunn's test. Significance level was set at 5% (p <.05) for all assessed parameters. Results: Micro‐CT revealed statistically significant differences in bone resorption which was greater in the AP + S group (p <.05), but no differences were observed between the Control and AP + S + PRO groups (p >.05). The AP + S + PRO group had a lower intensity and extent of inflammatory infiltrate compared to the AP + S group with smaller areas of bone loss (p < 0.05). The gene expression of RANKL and TRAP was significantly higher in the stressed group AP + S compared to the control group (p <.05), and a significantly higher OPG expression was observed in AP + S + PRO compared to the AP + S group (p <.05). Conclusions: Oral administration of propranolol had a significant effect on the AP severity in stressed rats, suggesting an anti‐inflammatory effect and a protective role on bone resorption of AP in stressed animals. Further research is necessary to fully comprehend the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Dental Science is the property of Brazilian Dental Science Journal-ICT-UNESP and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of nanoscale biomaterials associated with polymers has been growing over the years, due to their important structural characteristics for applications in biological systems. The present study aimed to produce and test polymeric scaffolds composed of polylactic acid (PLA) fibers associated with a 58S bioglass doped with therapeutic ions for use in tissue engineering. Three 58S Bioglass was obtained by the sol–gel route, pure and doped with 5% strontium and cobalt ions. Solutions of 7% PLA was used as control and added the three different bioglass, 4% of 58S bioglass (PLA‐BG), 4% bioglass‐doped strontium (PLA‐BGSr) and 4% bioglass‐doped cobalt (PLA‐BGCo). Scaffolds were produced through electrospinning process, and was characterized chemical and morphologically. The in vitro tests were performed using mesenchymal cells cultures from femurs of nine rats, grown in osteogenic supplemented total culture medium. After osteoblastic differentiation induction cell viability, alkaline phosphatase activity, total protein content quantification, and visualization of mineralization nodule tests were performed. Analysis of normal distribution used the Shapiro–Wilk test (nanofibers diameter and biological assay). Data were compared using the Kruskal–Wallis nonparametric test (p = 0.05). The bioglasses produced proved to be free of nitrate, chlorinated and nano‐sized, with effective incorporation of therapeutic ions in their structure. All materials showed cell viability (>70%), total protein production, and alkaline phosphatase activity. It was possible to develop polylactic acid scaffolds associated with 58S bioglass doped with therapeutic ions without cytotoxicity. Scaffolds characteristics appear to sustain its application in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Purpose: Diabetes mellitus (DM) affects the processes of repair, wound healing, and bone remodeling. This study was conducted to evaluate autologous bone graft integration, either with or without guided bone regeneration, through analyzing the expression of bone reabsorption markers and neovascularization in rats suffering from DM. Materials and Methods: Thirty adult Wistar rats were divided into two groups: The DM group received an injection of alloxan monohydrate (150 mg/kg), and the control group received an injection of sterile saline. Fifteen days afterward, an autologous bone grafting was performed in each of their arches, with the insertion of a membrane into the left arch. Euthanasia occurred in 7, 21, or 60 days after the surgery. Bone samples were processed for histomorphometric and immunohistochemical analyses. Results: After a statistical analysis of the data, the presence of DM did not interfere negatively in the bone autograft repair. The collagen membrane favored the graft integration into the recipient bed and the bone neoformation around the graft. Greater vascularization was observed between 21 and 60 days after the surgery, which increased bone formation and resulted in the graft integration. Only the RANK marker showed a significant difference in the glycemic groups. Transglutaminase 2 was significant for the membrane presence and experimental time. Conclusion: It is hence concluded that diabetes mellitus does not interfere with bone reabsorption via the RANK/RANKL/OPG. The graft integration was similar between the groups; however, the results of hyperglycemia with the collagen membrane indicate greater bone growth after graft placement. [ABSTRACT FROM AUTHOR]

Background/aim: In addition to their anti-inflammatory and anti-osteoclastogenesis properties, adrenergic blockers may also have promising anti-resorptive effects that can prevent root resorption when teeth are replanted because of avulsion. The aim of this study was to investigate the effects of phentolamine (Ph) and propranolol (Pr) in gels on the repair process of late replanted rat incisors. A further aim was to evaluate the biocompatibility of both drugs to human periodontal ligament fibroblasts (HPDLFs).Materials and Methods: Forty-eight maxillary right incisors were extracted from male Wistar rats, stored in paper napkins for 60 minutes, and randomly allocated to one of eight groups (n = 6). The root canal, root surface, and alveolus were treated with 0.75 µg/mL Ph gel (Ph0.75), 10 µg/mL Ph gel (Ph10), 100 µg/mL Ph gel (Ph100), 2.5 µg/mL Pr gel (Pr2.5), 10 µg/mL Pr gel (Pr10), 100 µg/mL Pr gel (Pr100), or sodium carboxymethylcellulose gel (CMC) before replantation. In the control group (CH), only the root canal was treated with calcium hydroxide paste. Thirty days following surgery, the animals were euthanized, and the right hemimaxilla was removed to perform micro-CT and histomorphometric analysis to determine osteoclastic activity. Ethanolic solutions of Ph10 and Pr10 were selected based on the in vivo study, and the viability of HPDLFs stimulated with lipopolysaccharide was determined by MTT assays.Results: The micro-CT and histomorphometric analysis revealed no significant differences among the treatments (P > .05). The presence of active osteoclasts was significantly decreased in the Ph10 and Pr10 groups (P < .05). Ph10 and Pr10 produced statistically similar cell survival rates compared to the control group (P > .05).Conclusions: Ph10 and Pr10 significantly decreased osteoclastogenesis in delayed replanted rat teeth and were not cytotoxic toward HPDLFs. [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a widely studied polymer and it has been found that porous PHBV materials are suitable for substrates for cell cultures. A crucial factor for scaffolds designed for tissue engineering is the water uptake. This property influences the transport of water and nutrients into the scaffold, which promotes cell growth. PHBV has significant hydrophobicity, which can harm the production of cells. Thus, the addition of α-wollastonite (WOL) can modify the PHBV scaffold's water uptake. To our knowledge, a kinetics study of water uptake of α-wollastonite phase powder and the PHBV matrix has not been reported. In this work, PHBV and WOL, (PHBV/WOL) films were produced with 0, 5, 10, and 20 wt % of WOL. Films were characterized, and the best concentrations were chosen to produce PHBV/WOL scaffolds. The addition of WOL in concentrations up to 10 wt % increased the cell viability of the films. MTT analysis showed that PHBV/5%WOL and PHBV/10%WOL obtained cell viability of 80% and 98%, respectively. Therefore, scaffolds with 0, 5 and 10 wt % of WOL were fabricated by thermally induced phase separation (TIPS). Scaffolds were characterized with respect to morphology and water uptake in assay for 65 days. The scaffold with 10 wt % of WOL absorbed 44.1% more water than neat PHBV scaffold, and also presented a different kinetic mechanism when compared to other samples. Accordingly, PHBV/WOL scaffolds were shown to be potential candidates for biological applications. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum: Health Sciences is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Stomatologica Croatica is the property of Acta Stomatologica Croatica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Universidade Estadual Paulista. Revista de Odontologia is the property of Universidade Estadual Paulista. Revista de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to evaluate the resorption process during the repair of autogenous bone grafts with or without coverage by an expanded polytetrafluoroethylene (e-PTFE) membrane in female rats with estrogen deficiency using the immunohistochemical technique. Eighty female rats were randomly divided into two groups (OVX and SHAM). The 40 female rats in the OVX group were subjected to ovariectomy, and the 40 female rats in the SHAM group were subjected to simulated ovariectomy. The two groups were further divided in subgroup E, which was subjected to surgery for placement of autogenous bone graft (ABG), and subgroup ME, in which the ABG was covered with an e-PTFE membrane. The animals were killed at 0, 7, 21, 45 and 60 days. The specimens were analyzed using immunohistochemistry for the bone resorption markers RANK, RANK-L and Osteoprotegerin (OPG). A higher remodeling rate was observed at 7 and 21 days after the autogenous bone grafts, when the markers were more intensely expressed. At the final time point, the specimens presented similar characteristics to those observed at the initial time point. The expression of immunohistochemical markers was not altered by the estrogen deficiency. The presence of the e-PTFE membrane delayed the bone resorption process, influencing the immunohistochemical expression of markers. [ABSTRACT FROM AUTHOR]

Lichen planus (LP) is a mucocutaneous disease with well-established clinical and microscopic features. The oral mucosa and skin may present clinical and microscopic alterations similar to those observed in LP, called lichenoid reactions (LRs), which are triggered by systemic or topical etiological agents. The difficulties faced to establish the differential diagnosis between the two pathologies were investigated in the literature. It was observed that the etiology of LP is still under discussion, with a tendency to self-immunity, while the etiology of LRs is related to the contact with specific agents, such as metallic restorative materials, resins, and drugs, allowing the establishment of a cause-effect relationship. In this case, the disease is caused by the antigen fixation in the epithelial cells, which are destructed by the immune system. Based on these data, protocols are suggested for this differentiation. The important role played by the integration between the clinician and the oral pathologist in the diagnostic process is highlighted. The treatment of LP comprises mainly the utilization of corticosteroids and the LR is treated by removal of the causal factor. Differentiation between the two diseases allows an effective and correct therapeutic approach. [ABSTRACT FROM AUTHOR]

Background. New surface treatments have been proposed to expand the clinical indications of zirconia prostheses. This study aimed to evaluate the effect of silica and fluorine nanofilms on zirconia ceramic on the resin cement bond strength. Methods. Zirconia blocks and discs underwent different surface treatments: untreated zirconia (CON), sandblasted, silica-coated alumina particles (30 µm) (SC), silica nanofilm (SN), and fluorine nanofilm (FN). Nanofilm deposition was performed through plasma enhanced chemical vapor deposition (PECVD). Zirconia surfaces were characterized on disks by morphology (atomic force microscopy, AFM), chemical analysis (x-ray photoelectron spectroscopy, XPS), and contact angle analysis. A silane coupling agent was applied on each treated surface, and a cylinder of resin cement was built up. Half of the specimens in each group were submitted to 6000 thermal cycles (TC). Bond strength was analyzed using the shear test, and the fractographic analysis was performed with stereomicroscopy and SEM/EDS. Statistical analysis was performed through one-way ANOVA and Tukey test in the non-aged and aged specimens. Results. Nanofilms modified the zirconia surface, which became more hydrophilic and chemically reactive. Chemical bonding between Si-O was found in SN, and FN promoted a fluorination process on the ceramic surface, converting zirconia into zirconium oxyfluoride. Specimens of the SN (TC) group failed on pre-testing. FN (TC) bond strength (3.8 MPa) was lower than SC (TC) and CON (TC) after shearing. Adhesive failure predominated in the experimental groups. Silica nanofilm failure occurred after aging. Conclusion. Silica and fluorine nanofilms deposited by PECVD did not promote effective bonding between zirconia and resin cement., (©2022 The Author(s).)

A mandibular buccal bifurcation cyst is an inflammatory cyst that usually occurs on the buccal aspect of the permanent mandibular first molar of children. This lesion is diagnosed by an association of radiographic, clinical, and histological features. We report a bilateral case of mandibular buccal bifurcation cyst and discuss the main findings of this entity. A 7-year-old girl presented pain and delayed dental eruption in the posterior mandibular region. A cone beam computed tomography was performed and revealed hypodense lesions involving the crown and root of the mandibular first molars, with expansion of the buccal cortical and lingual tilting of the molar roots. A biopsy was carried out, and the common features of an inflammatory odontogenic cyst were histologically observed. The final diagnosis was bilateral mandibular buccal bifurcation cyst. Clinicians need to be aware of this diagnostic possibility in cases of mandibular cysts in children-especially when bilateral-to perform the correct treatment, which should not involve the extraction of the affected tooth., Competing Interests: Conflict of Interest: None

The torus palatinus is a unilocular or multilocular exostosis that occurs in the midline of the hard palate. It is considered a common clinical finding. Magnetic resonance imaging (MRI) is not commonly used in dentistry and descriptions of the torus by this imaging method are therefore rare in the literature. This case study reports on a female patient referred to the dentist to elucidate a bone enlargement detected by MRI, which was requested by the physician who accompanied the patient for migraine treatment. Additional routine dental imaging exams were performed for the planning of different treatments. Here is a description of the torus palatinus along with MRI in order to provide a complete representation of the clinical finding.

Purpose: To analyze and compare bone apposition at the interface of commercially available rough-surfaced, threaded implants with porous-surfaced, cylindrical implants after several healing periods in a rabbit model. In addition, the study aimed to elucidate the influence of the implant surface configuration on Streptococcus mutans adherence., Materials and Methods: Using a powder metallurgy technique, a new method was developed to produce titanium implants with a dense core and porous surface to increase bone-implant contact (BIC). Sixty implants were placed in 15 rabbits. In each rabbit, two experimental and two control implants were placed in the right or left tibia. The experimental implants were inserted under pressure into the surgical cavity, while the control implants were self-threaded. The rabbits were euthanized at 4, 8, and 12 weeks postinsertion for undecalcified histologic processing and morphometric evaluation of BIC. Additionally, 16 implants, eight experimental and eight control, were incubated with S. mutans to evaluate adherence for each type of implant. Analysis of variance with repeated measures and the Student t test were applied, respectively., Results: Histology showed intimate bone-implant interfaces without soft tissue intervention in both groups. Porous-surfaced cylindrical implants showed a higher BIC (72.41% ± 9.47%) than the rough-surfaced screw implants (61.23% ± 14.12%) (P = .013), while no significant difference in S. mutans adherence occurred (P = .351). The implant type effect was more pronounced in the 4-week healing period groups (P = .029). The percentage of BIC was similar throughout the healing periods (P = .333), but gradually increased over time., Conclusion: Within the limitations of this study, the results suggest that the new implant design increased BIC without provoking greater S. mutans adherence.