The profile of patients with maxillofacial trauma due to interpersonal violence treated in a hospital emergency room.

AIM: This study evaluated records of patients with maxillofacial trauma due to interpersonal violence (IPV) being treated in the emergency room of a level I trauma center hospital in São Paulo, Brazil. MATERIAL AND METHODS: Data of patients with maxillofacial trauma due to IPV recorded between January 2019 and December 2019 were retrospectively examined. Personal data, days on which they experienced IPV, and the type of maxillofacial trauma sustained were extracted and statistically analyzed (p < .050). RESULTS: During the analysis, 1034 patients with maxillofacial trauma were identified; of these patients, 292 (28.2%) who experienced trauma due to IPV were included in this study. There was a mean age of 32.6 years and the most common type of trauma was soft tissue injuries (38.7%). Mandible and nose fractures were more prevalent in males and females, respectively. Our data, when compared with other studies on maxillofacial trauma due to IPV, showed a lower prevalence and male-to-female ratio, and a higher presence of dentoalveolar trauma. Additionally, our data when compared with studies on maxillofacial trauma due to other causes showed lower mean age and male-to-female ratios, and a higher occurrence of nose fractures differing from the predominance of mandibular fractures. CONCLUSION: Oral and maxillofacial surgeons must be able to suspect and identify cases due to IPV among their patients with trauma. With our results, although each case has its individuality, we can suggest that cases of maxillofacial trauma in young, female, and nasal fracture patients may be suspicious for IPV.

Effect of osteoblasts on osteoclast differentiation and activity induced by titanium with nanotopography.

Titanium with nanotopography (Ti Nano) favors osteoblast differentiation and attenuates the osteoclast inhibitory effects on osteoblasts. Because the interactions between nanotopography and osteoclasts are underexplored, the aims of this study were to evaluate the effects of Ti Nano on osteoclast differentiation and activity, and the influence of osteoblasts on osteoclast-Ti Nano interaction. The discs were conditioned with a mixture of 10 N H2SO4 and 30% aqueous H2O2 to create Ti Nano and non-conditioned Ti discs were used as control (Ti Control). Osteoclasts were cultured on Ti Control and Ti Nano in the presence of osteoblasts in an indirect co-culture system. Also, osteoclasts were cultured on polystyrene and calcium phosphate plates in conditioned media by osteoblasts grown on Ti Control and Ti Nano. While Ti Control exhibited an irregular and smooth surface, Ti Nano presented nanopores distributed throughout the whole surface. Additionally, anisotropy was higher on Ti Nano than Ti Control. Nanotopography favored the gene expression of osteoclast markers but inhibited osteoclast differentiation and activity, and the presence of osteoblasts enhanced the effects of Ti Nano on osteoclasts. Such findings were mimicked by conditioned medium of osteoblasts cultured on Ti Nano, which reduced the osteoclast differentiation and activity. In conclusion, our results indicated that nanotopography regulates osteoblast-osteoclast crosstalk and further investigations should focus the impact of these bone cell interactions on Ti osseointegration.

Mesenchymal Stem Cells Combined with a P(VDF-TrFE)/BaTiO3 Scaffold and Photobiomodulation Therapy Enhance Bone Repair in Rat Calvarial Defects.

BACKGROUND: Tissue engineering and cell therapy have been the focus of investigations on how to treat challenging bone defects. This study aimed to produce and characterize a P(VDF-TrFE)/BaTiO3 scaffold and evaluate the effect of mesenchymal stem cells (MSCs) combined with this scaffold and photobiomodulation (PBM) on bone repair. METHODS AND RESULTS: P(VDF-TrFE)/BaTiO3 was synthesized using an electrospinning technique and presented physical and chemical properties suitable for bone tissue engineering. This scaffold was implanted in rat calvarial defects (unilateral, 5 mm in diameter) and, 2 weeks post-implantation, MSCs were locally injected into these defects (n = 12/group). Photobiomodulation was then applied immediately, and again 48 and 96 h post-injection. The µCT and histological analyses showed an increment in bone formation, which exhibited a positive correlation with the treatments combined with the scaffold, with MSCs and PBM inducing more bone repair, followed by the scaffold combined with PBM, the scaffold combined with MSCs, and finally the scaffold alone (ANOVA, p ≤ 0.05). CONCLUSIONS: The P(VDF-TrFE)/BaTiO3 scaffold acted synergistically with MSCs and PBM to induce bone repair in rat calvarial defects. These findings emphasize the need to combine a range of techniques to regenerate large bone defects and provide avenues for further investigations on innovative tissue engineering approaches.

Photobiomodulation using 940-nm laser as an adjuvant therapy on orthognathic surgery: A randomized clinical trial.

This study aimed to evaluate the effectiveness of photobiomodulation (PBM) therapy using 940-nm laser in patients undergoing orthognathic surgery. Twenty individuals were randomly distributed into laser (n = 10) and control (n = 10) groups. The PBM was conducted immediately after surgery, after 24 h, 48 h, and weekly for up to 4 weeks. All participants were evaluated for pain, edema, trismus and paresthesia. Data were compared by Fisher's and Mann-Whitney or chi-square tests (5%). The pain decreased from 24 h to 4 weeks, with the laser group reaching any pain after 3 weeks (p < 0.001). A significant difference was noticed for trismus on days 14 and 30 (p = 0.002; p = 0.019), without difference in paresthesia (p = 0.198). Edema was lower on the laser group compared to control, without a significant difference for most measurements. Data indicate that 940-nm PBM therapy decreased the occurrence of postoperative pain and significantly improved trismus.

Oral mucocele exhibiting an extraoral swelling: a case report of an atypical presentation / Mucocele oral exibindo edema extraoral: relato de caso atípico

ABSTRACT Despite being common pathological entities found in the oral cavity, oral mucoceles can present distinct features, raising several diagnostic possibilities and treatments. In this study, we report the case of a 34-year-old man with an asymptomatic increased volume in the left periorbital region of more than a year, without remission or associated trauma. An aspiration biopsy was performed, followed by an excisional biopsy, and the specimen was sent for histopathological examination. Results led to the diagnosis of an oral mucocele. Surgical removal was performed in an excisional biopsy. Subsequently, the patient recovered promptly without further complications. Although oral mucoceles recur relatively often, its prognosis is good. This case emphasizes the importance of obtaining a detailed disease history, knowledge of its clinical features, and etiopathogenesis combined with complementary examinations to establish diagnostic hypotheses and converge on an adequate and individualized treatment plan

RESUMO Apesar de serem entidades patológicas comumente encontradas na cavidade oral, as mucoceles podem apresentar características distintas, o que pode sugerir diversas possibilidades diagnósticas e de tratamento. Paciente do gênero masculino, 34 anos, compareceu ao ambulatório com queixa de aumento de volume assintomático na região periorbitária esquerda há mais de um ano, sem remissão ou trauma associado. Foi realizada biópsia aspirativa seguida de biópsia excisional e a amostra encaminhada para exame histopatológico, que confirmou o diagnóstico de mucocele oral. O paciente evoluiu sem queixas e sem recidiva. Apesar da alta taxa de recorrência, mucoceles orais têm um bom prognóstico. Este relato de caso enfatiza a importância da obtenção de uma história detalhada da doença, do conhecimento de suas características clínicas e da etiopatogenia, para estabelecer hipóteses diagnósticas e convergir para um plano de tratamento adequado e individualizado.

Poly-ε-caprolactone/poly(rotaxane) seeded with human dental pulp stem cells or osteoblasts promotes angiogenesis: a chorioallantoic membrane assay.

Biomaterials used for tissue regeneration should ideally provide a favorable environment for cell proliferation and differentiation. Angiogenesis is crucial for supplying oxygen and nutrients necessary for cellular survival at implantation sites. The aim of this study was to evaluate the overall angiogenesis response of a poly ε-caprolactone/poly (rotaxane) blend (poly-blend) carried by human dental pulp stem cells (hDPSCs) or osteoblasts (OB) seeded in the chorioallantoic membranes (CAM) of fertilized chicken eggs on embryonic day 7. They were classified into the following intervention groups: (a) poly(polymeric blend disks free of cells); (b) hDPSC seeded onto CAM; (c) poly/hDPSC (where hDPSCs were seeded onto poly-blend); (d) poly/OB (where osteoblasts were seeded onto poly); (e) OB (where hDPSCs differentiated into osteoblasts were seeded onto CAM); and (f) a negative control when a sterilized silicone ring free of cells or polymer was inserted into CAM. On embryonic day 14, the quantitative and qualitative characteristics of the blood vessels in the CAMs were analyzed macroscopically and microscopically. Macroscopic examination showed that the Poly/hDPSC samples exhibited an increased medium vessel density. Additionally, microscopic observations showed that the Poly/hDPSC group and poly alone resulted in a large lumen area of vascularization. Thus, poly ε-caprolactone/poly (rotaxane) did not impair angiogenesis. Furthermore, poly-blend carried by stem cells of dental pulp origin shows a better vasculogenic potential, which is essential for regenerative therapies.

Superparamagnetic and highly bioactive SPIONS/bioactive glass nanocomposite and its potential application in magnetic hyperthermia.

Magnetic bioactive glass-ceramics are biomaterials applied for magnetic hyperthermia in bone cancer treatment, thereby treating the bone tumor besides regenerating the damaged bone. However, combining high bioactivity and high saturation magnetization remains a challenge since the thermal treatment step employed to grow magnetic phases is also related to loss of bioactivity. Here, we propose a new nanocomposite made of superparamagnetic iron oxide nanoparticles (SPIONs) dispersed in a sol-gel-derived bioactive glass matrix, which does not need any thermal treatment for crystallization of magnetic phases. The scanning and transmission electron microscopies, X-ray diffraction, and dynamic light scattering results confirm that the SPIONs are actually embedded in a nanosized glass matrix, thus forming a nanocomposite. Magnetic and calorimetric characterizations evidence their proper behavior for hyperthermia applications, besides evidencing inter-magnetic nanoparticle interactions within the nanocomposite. Bioactivity and in vitro characterizations show that such nanocomposites exhibit apatite-forming properties similar to the highly bioactive parent glass, besides being osteoinductive. This methodology is a new alternative to produce magnetic bioactive materials to which the magnetic properties only rely on the quality of the SPIONs used in the synthesis. Thereby, these nanocomposites can be recognized as a new class of bioactive materials for applications in bone cancer treatment by hyperthermia.

Photobiomodulation treatments drive osteogenic versus adipocytic fate of bone marrow mesenchymal stem cells reversing the effects of hyperglycemia in diabetes.

Diabetes mellitus (DM) is a chronic metabolic disease that affects bone metabolism, which can be related to a reduced osteogenic potential of bone marrow mesenchymal stem cells (BM-MSCs). MSCs from diabetic rats (dBM-MSC) have shown a tendency to differentiate towards adipocytes (AD) instead of osteoblasts (OB). Since photobiomodulation (PBM) therapy is a non-invasive treatment capable of recovering the osteogenic potential of dBM-MSCs, we aimed to evaluate whether PBM can modulate MSC's differentiation under hyperglycemic conditions. BM-MSCs of healthy and diabetic rats were isolated and differentiated into osteoblasts (OB and dOB) and adipocytes (AD and dAD). dOB and dAD were treated with PBM every 3 days (660 nm; 5 J/cm2; 0.14 J; 20 mW; 0.714 W/cm2) for 17 days. Cell morphology and viability were evaluated, and cell differentiation was confirmed by gene expression (RT-PCR) of bone (Runx2, Alp, and Opn) and adipocyte markers (Pparγ, C/Ebpα, and C/Ebpß), production of extracellular mineralized matrix (Alizarin Red), and lipid accumulation (Oil Red). Despite no differences on cell morphology, the effect of DM on cells was confirmed by a decreased gene expression of bone markers and matrix production of dOB, and an increased expression of adipocyte and lipid accumulation of dAD, compared to heatlhy cells. On the other hand, PBM reversed the effects of dOB and dAD. The negative effect of DM on cells was confirmed, and PBM improved OB differentiation while decreasing AD differentiation, driving the fate of dBM-MSCs. These results may contribute to optimizing bone regeneration in diabetic patients.

Bioactive glass-ceramic for bone tissue engineering: an in vitro and in vivo study focusing on osteoclasts.

Despite the crucial role of osteoclasts in the physiological process of bone repair, most bone tissue engineering strategies have focused on osteoblast-biomaterial interactions. Although Biosilicate® with two crystalline phases (BioS-2P) exhibits osteogenic properties and significant bone formation, its effects on osteoclasts are unknown. This study aimed to investigate the in vitro and in vivo effects of BioS-2P on osteoclast differentiation and activity. RAW 264.7 cells were cultured in osteoclastogenic medium (OCM) or OCM conditioned with BioS-2P (OCM-BioS-2P), and the cell morphology, viability, and osteoclast differentiation were evaluated. BioS-2P scaffolds were implanted into rat calvarial defects, and the bone tissue was evaluated using tartrate-resistant acid phosphatase (TRAP) staining and RT-polymerase chain reaction (PCR) after 2 and 4 weeks to determine the gene expressions of osteoclast markers and compare them with those of the bone grown in empty defects (Control). OCM-BioS-2P favored osteoclast viability and activity, as evidenced by an increase in the TRAP-positive cells and matrix resorption. The bone tissue grown on BioS-2P scaffolds exhibited higher expression of the osteoclast marker genes (Ctsk, Mmp 9, Rank) after 2 and 4 weeks and the RankL/Opg ratio after 2 weeks. Trap gene expression was lower at 2 weeks, and a higher number of TRAP-stained areas were observed in the newly formed bone on BioS-2P scaffolds at both 2 and 4 weeks compared to the Controls. These results enhanced our understanding of the role of bioactive glass-ceramics in bone repair, and highlighted their role in the modulation of osteoclastic activities and promotion of interactions between bone tissues and biomaterials.

Do the stages of orthodontic-surgical treatment affect patients' quality of life and self-esteem?

The orthodontic-surgical treatment comprises different stages from diagnosis to final soft tissue accommodation, but there are no data regarding the patient's perception during these phases. This study aimed to investigate the impact of these stages on quality of life and self-esteem of patients with dentofacial deformity. Patients were divided into 4 groups according to the treatment stage: initial orthodontic pre-treatment (1), one week before surgery (2), three months after surgery (3), and after the removal of the orthodontic appliance (4) (n = 20 / group). They filled the following questionnaires: Oral Health Impact Profile (OHIP-14), Orthognathic Quality of Life Questionnaire (OQLQ) and Rosenberg Self-Esteem Scale (RSES). Data were evaluated by Kruskal-Wallis test. Differences among groups were noticed in all evaluated scales (p = 0.001 for all). No statistically significant differences between patients in groups 1 and 2 (OHIP, OQLQ, and RSES, p >0.05 for all), while patients at group 4 presented different scores in all questionnaires compared to 1, 2, and 3 (p < 0.05 for all), irrespective of the type of dentofacial deformity (p > 0.05). The results indicate that dental decompensation stage did not negatively affect patient's confidence and well-being. Despite the improvement noticed few months after the orthognathic surgery, the main impact on patient's quality of life and self-esteem was evidenced after the removal of the orthodontic appliance. We highlight the important role of counselling patients to discuss all the treatment stages to clarify patients' subjective expectations before any intervention is carried out.

Bioactive glass-ceramic for bone tissue engineering: an in vitro and in vivo study focusing on osteoclasts

Abstract: Despite the crucial role of osteoclasts in the physiological process of bone repair, most bone tissue engineering strategies have focused on osteoblast-biomaterial interactions. Although Biosilicate® with two crystalline phases (BioS-2P) exhibits osteogenic properties and significant bone formation, its effects on osteoclasts are unknown. This study aimed to investigate the in vitro and in vivo effects of BioS-2P on osteoclast differentiation and activity. RAW 264.7 cells were cultured in osteoclastogenic medium (OCM) or OCM conditioned with BioS-2P (OCM-BioS-2P), and the cell morphology, viability, and osteoclast differentiation were evaluated. BioS-2P scaffolds were implanted into rat calvarial defects, and the bone tissue was evaluated using tartrate-resistant acid phosphatase (TRAP) staining and RT-polymerase chain reaction (PCR) after 2 and 4 weeks to determine the gene expressions of osteoclast markers and compare them with those of the bone grown in empty defects (Control). OCM-BioS-2P favored osteoclast viability and activity, as evidenced by an increase in the TRAP-positive cells and matrix resorption. The bone tissue grown on BioS-2P scaffolds exhibited higher expression of the osteoclast marker genes (Ctsk, Mmp 9, Rank) after 2 and 4 weeks and the RankL/Opg ratio after 2 weeks. Trap gene expression was lower at 2 weeks, and a higher number of TRAP-stained areas were observed in the newly formed bone on BioS-2P scaffolds at both 2 and 4 weeks compared to the Controls. These results enhanced our understanding of the role of bioactive glass-ceramics in bone repair, and highlighted their role in the modulation of osteoclastic activities and promotion of interactions between bone tissues and biomaterials.

Recovering the osteoblastic differentiation potential of mesenchymal stem cells derived from diabetic rats by photobiomodulation therapy.

Autologous cell-based therapy for bone regeneration might be impaired by diabetes mellitus (DM) due to the negative effects on mesenchymal stem cells (MSCs) differentiation. Strategies to recover their osteogenic potential could optimize the results. We aimed to evaluate the effect of photobiomodulation (PBM) therapy on osteoblast differentiation of rats with induced DM. Bone marrow MSCs of healthy and diabetic rats were isolated and differentiated into osteoblasts (OB and dOB, respectively). dOB were treated with PBM therapy every 72 hour (660 nm; 0.14 J; 20 mW; 0.714 W/cm2 , and 5 J/cm2 ). Cell morphology, viability, gene and protein expression of osteoblastic markers, alkaline phosphatase (ALP) activity, and the mineralized matrix production of dOB-PBM were compared to dOB. PBM therapy improved viability of dOB, increased the gene and protein expression of bone markers, the ALP activity and the mineralized matrix production. PBM therapy represents an innovative therapeutic approach to optimize the treatment of bone defects in diabetic patients.

Can diagnostic changes caused by cone beam computed tomography alter the clinical decision in impacted lower third molar treatment plan?

OBJECTIVES: This study observed whether changes in diagnosis caused by analysis of three-dimensional images can lead to alterations in the treatment plans of impacted lower third molars (ILTMs). METHODS: Sets of panoramic (PAN) - cone beam computed tomography (CBCT) of 218 patients were assessed for ILTM classification, contact with mandibular canal, contact and resorption of the lower second molar (LSM), intraoperative planning and post-operative expectations. RESULTS: Percentage agreement and McNemar test compared PAN vs CBCT assessments. Logistic regression analyzed the dependency of change in surgical planning considering the changes in diagnostic features; descriptive statistics was used to observe the expectation of post-operative complications and paresthesia. Differences were found between PAN vs CBCT for classification of impaction and positioning, LSM relationship, choice for crown and root sectioning and expectation of post-operative complications (all with p < 0.001). Logistic regression indicated that the change in diagnosis caused by CBCT examination did not change the clinical decision to extract ILTM but altered the planning of intraoperative steps such as osteotomy, crown sectioning and relaxing incision. The expectation of post-operative complications decreased when professionals planned the ILTM removal using tri-dimensional images. CONCLUSIONS: We concluded that changes in the diagnosis after CBCT examination can lead to alterations in the treatment plan of impacted lower third molar.

Photobiomodulation as adjunctive therapy for guided bone regeneration. A microCT study in osteoporotic rat model.

Regeneration of diseased bone is challenging. Guided bone regeneration (GBR) has been applied to favor the bone repair. Photobiomodulation (PBM) is also a recognized therapy able to improve bone repair in healthy and diseased individuals. Thus, with the hypothesis that PBM therapy could improve the GBR of diseased bone, this study evaluated the effect of PBM as adjunctive therapy to GBR in osteoporotic rats. Osteoporosis was induced in rats using the oophorectomy model. Then, 5-mm calvaria bone defects were created and treated according to the experimental groups, as follows: with no further treatment (Control); conventional GBR (Membrane), GBR and PBM applied with 3 s, 4 J/cm2 and 0.12 J per point (PBM-1) and GBR and PBM applied with 10s, 14 J/cm2, 0.4 J per point (PBM-2). PBM therapy (808 nm, 40 mW, 1.42 W/cm2) was applied immediately, 48 and 96 h postoperatively. Four and eight weeks later, the samples were harvested and processed for micro-computerized tomography (Micro CT). Data were statistically compared (p < 0.05). From 4 to 8 weeks mostly significant changes were observed in the PBM groups. The bone volume fraction and number of trabeculae of the PBM groups, especially the PBM-1, were significantly higher than those of Control (p < 0.0001). The values of thickness and separation of the trabeculae and structural model index of the PBM groups were significantly smaller than Control (p < 0.0001). The connectivity density was significantly higher on Membrane and PBM groups than Control (p < 0.0004). The application of PBM as adjunctive therapy to GBR results in enhanced bone formation and maturation in comparison to the conventional GBR in the regeneration of lesions of osteoporotic bone in rats. Overviewing the challenges that face bone regeneration in patients with osteoporosis, our findings open new perspectives on the treatment of bone defects under osteoporotic conditions.

Role of embryonic origin on osteogenic potential and bone repair capacity of rat calvarial osteoblasts.

INTRODUCTION: The aim of this study was to evaluate the in vitro osteogenic potential of osteoblasts from neural crest-derived frontal bone (OB-NC) and mesoderm-derived parietal bone (OB-MS) and the bone formation induced by them when injected into calvarial defects. MATERIALS AND METHODS: Calvarial bones were collected from newborn Wistar rats (3-day old) and characterized as frontal and parietal prior to OB-NC and OB-MS harvesting. The cells were cultured, and several parameters of osteoblast differentiation were evaluated. These cells, or PBS without cells (control), were locally injected into 5-mm rat calvarial defects (5 × 106 cells/defect) and after 4 weeks bone formation was evaluated by morphometric and histological analyses. RESULTS: The characterization of frontal and parietal bones assured the different embryonic origin of both cell populations, OB-NC and OB-MS. The OB-NC presented higher proliferation while the OB-MS presented higher alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of runt-related transcription factor 2, Alp, bone sialoprotein and osteocalcin revealing their high osteogenic potential. µCT analysis indicated that there was higher amount of bone formation in defects injected with both OB-NC and OB-MS compared to the control. Moreover, the bone tissue formed by both cells displayed the same histological characteristics. CONCLUSIONS: Despite the distinct in vitro osteogenic potential, OB-NC and OB-MS induced similar bone repair in a rat calvarial defect model. Thus, osteoblasts, irrespective of their in vitro osteogenic potential linked to embryonic origins, seem to be suitable for cell-based therapies aiming to repair bone defects.

Photobiomodulation as an adjunctive therapy for alveolar socket preservation: a preliminary study in humans.

Bone remodeling results in loss of alveolar bone height and thickness. Photobiomodulation (PBM) based on photochemical stimulation by low-intensity lasers emerges as an adjunctive therapy for alveolar socket preservation. Our study aimed to evaluate the effects of PBM therapy on alveolar bone repair. Twenty healthy patients in need of bilateral extraction of lower molars were enrolled in this split-mouth randomized and blind clinical trial. The extraction sites were randomly selected to receive either the PBM therapy with a CW GaAIAs diode laser (808 nm; 0.028 mm2; 0.1 W; 3.6 W/cm2; 89 J/cm2; 2.5 J/point) or no treatment (Control). Bone biopsies were harvested 45 days after the dental extraction and evaluated using micro-computerized tomography (µCT), morphometric, and histological analysis. Data were compared using the paired t test, and the level of significance was set at 5%. Bone surface (p = 0.029), bone surface/total volume (p = 0.028), trabecular number (p = 0.025), and connectivity density (p = 0.029) were higher at the PBM group compared with Control. The histological observations confirmed the µCT findings. PBM samples exhibited higher number of organized and connected bone trabeculae along with higher density of blood vessels than Control. Control samples displayed a dense and highly cellular connective tissue at the central area accompanied by the presence of immature bone trabeculae at the periphery. Our results indicated that the PBM therapy improved the newly bone trabeculae formation and their connectivity which increased bone surface, indicating the positive effect of the laser on alveolar human socket repair.

Anterior lingual mandibular bone cavity: a case report / Cavidade óssea mandibular lingual anterior: um relato de caso

Stafne's bone cavity (SBC) is an asymptomatic lingual bone cavity situated near the angle of the mandible. The anterior variant of SBC, which shows a radiolucent unilateral ovoid lingual bone concavity in the canine-premolar mandibular region, is uncommon. A 73-year-old man was referred for assessment of loss of mandibular bone. Panoramic radiographs and computerized tomography scans showed a well-defined lingual bony defect in the anterior mandible. Analysis of imaginological documentation, made 14 years ago, revealed a progressive increase in mesiodistal diameter and intraosseous bony defect. The soft tissue obtained within the bony defect, microscopically revealed fibrous stroma containing blood vessels of varied caliber. The current anterior lingual mandibular bone defect case is probably caused by the salivary gland entrapped or pressure resorption, which can explain the SBC pathogenesis (AU)

A cavidade óssea de Stafne (COS) é uma cavidade assintomática, localizada próximo ao ângulo da mandíbula, por lingual. A variante anterior da COS, a qual apresenta uma concavidade óssea lingual radiolúcida, ovoide e unilateral na região do caninopré-molar mandibular, é incomum. Um homem de 73 anos foi encaminhado para avaliação da perda óssea mandibular. A radiografia panorâmica e a tomografia computadorizada mostraram um defeito ósseo lingual bem definido na região anterior da mandibula. A análise da documentação imaginológica, realizada há 14 anos, revelou um aumento progressivo do diâmetro mesiodistal e defeito ósseo intraósseo. A biópsia do tecido mole obtido do defeito ósseo revelou microscópicamente estroma fibroso contendo vasos sanguíneos de calibre variado. O presente caso de defeito ósseo mandibular na região lingual anterior é provavelmente causado por glândula salivar aprisionada ou reabsorção por pressão, o que pode explicar a patogênese da COS. (AU)

Effect of cell therapy with allogeneic osteoblasts on bone repair of rat calvaria defects.

BACKGROUND AIMS: Regenerative medicine strategies based on cell therapy are considered a promising approach to repair bone defects. The aims of this study were to evaluate the effect of subculturing on the osteogenic potential of osteoblasts derived from newborn rat calvaria and the effect of these osteoblasts on bone repair of rat calvaria defects. METHODS: Cells were obtained from 50 newborn rat calvaria, and primary osteoblasts (OB) were compared with first passage (OB-P1) in terms of osteogenic potential by assaying cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of the osteoblastic markers RUNX2, ALP, osteocalcin and bone sialoprotein. Then, 5-mm calvaria defects were created in 24 Wistar rats, and after 2 weeks, they were locally injected with 50 µL of phosphate-buffered saline containing either 5 × 106 osteoblasts (OB-P1, n = 12) or no cells (control, n = 12). Four weeks post-injection, the bone formation was evaluated by micro-computed tomography and histological analyses. Data were compared by analysis of variance, followed by the Student-Newman-Keuls's test or Student's t-test (P ≤ 0.05). RESULTS: OB-P1 showed high proliferation and ALP activity, and despite the reduced gene expression of osteoblastic markers and extracellular matrix mineralization compared with OB, they displayed osteogenic potential, being a good choice for injection into calvaria defects. The micro-tomographic and histological data showed that defects treated with OB-P1 presented higher bone formation compared with control defects. DISCUSSION: Our results indicate that cells derived from newborn rat calvaria retain osteoblastic characteristics after subculturing and that these osteoblasts stimulate bone repair in a rat calvaria defect model.

Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible Augmentation.

Fresh frozen bone allografts (FFB) have become an alternative for bone augmentation in the past decades, especially because of the absence of recent reports of disease transmission or immunologic reactions when it is used. The aim of this prospective controlled study is to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible. Twenty consecutive patients presenting for reconstruction of posterior mandibular alveolar bone ridge width ≤6.0 mm and/or height ≤6.0 who met all inclusion and exclusion criteria were included. FFB blocks were used. The main outcome variable investigated was bone volume dynamics. Vertical, horizontal, and 3-dimensional bone gain data were measured from computerized tomography scans. The main predictor variable was time evaluated at 3 points: immediately after surgery (T1), at implant placement (T2), and 1 year after functional loading (T3). Secondary outcome parameters evaluated were implant survival, histologic findings, and microtomographic morphometry. The study included 28 hemi-mandibles, 50 FFB bone blocks, and 15 female and 5 male patients (mean age, 51.8 years). Block and implant survival rates were 100% and 96%, respectively, after 31.75 months of follow-up. Vertical and horizontal bone gain at T2 was 5.15 and 6.42 mm, respectively. Volumetric resorption was 31% at T2, followed by an additional 10% reduction at T3. Histologic evaluation showed newly formed vital bone in intimate contact with the remaining FFB. Microtomography revealed 31.8% newly formed bone, 14.5% remaining grafted bone, and 53.7% connective tissue and bone marrow. Thus, FFB blocks may lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implant-supported rehabilitation with high success rates.

Changes in actin and tubulin expression in osteogenic cells cultured on bioactive glass-based surfaces.

The present study evaluated whether the changes in the labeling pattern of cytoskeletal proteins in osteogenic cells cultured on bioactive glass-based materials are due to altered mRNA and protein levels. Primary rat-derived osteogenic cells were plated on Bioglass® 45S5, Biosilicate®, and borosilicate (bioinert control). The following parameters were assayed: (i) qualitative epifluorescence analysis of actin and tubulin; (ii) quantitative mRNA and protein expression for actin and tubulin by real-time PCR and ELISA, respectively, and (iii) qualitative analysis of cell morphology by scanning electron microscopy (SEM). At days 3 and 7, the cells grown on borosilicate showed typical actin and tubulin labeling patterns, whereas those on the bioactive materials showed roundish areas devoid of fluorescence signals. The cultures grown on bioactive materials showed significant changes in actin and tubulin mRNA expression that were not reflected in the corresponding protein levels. A positive correlation between the mRNA and protein as well as an association between epifluorescence imaging and quantitative data were only detected for the borosilicate. SEM imaging of the cultures on the bioactive surfaces revealed cells partly or totally coated with material aggregates, whose characteristics resembled the substrate topography. The culturing of osteogenic cells on Bioglass® 45S5 and Biosilicate® affect actin and tubulin mRNA expression but not the corresponding protein levels. Changes in the labeling pattern of these proteins should then be attributed, at least in part, to the presence of a physical barrier on the cell surface as a result of the material surface reactions, thus limiting fluorescence signals.