Mechanical properties of platelet-rich fibrin from patients on warfarin.

Platelet-rich fibrin (PRF) has been used increasingly in oral and maxillofacial surgery in recent years. The aim of this experimental study was to perform a mechanical evaluation of PRF from patients on warfarin. PRF samples were obtained from 21 patients on warfarin (mean INR 2.30 ± 0.89) and 21 non-anticoagulated patients (control; mean INR 1.08 ± 0.07). For the patients on warfarin, two experimental groups were formed based on the PRF centrifugation time: group A, 10 min (21 samples); group B, 18 min (20 samples). Control group samples (21 samples) were centrifuged for 10 min. Mechanical properties were evaluated by axial tensile test and suture retention test with an Instron 3345 universal testing machine. Mechanical parameters were compared between the groups using the Kruskal-Wallis test and Dunn's post-hoc test. Axial tensile values were similar in all groups. In the suture retention test, significantly lower values of deformation at maximum force were observed in the experimental group: group A (107.07 ± 25.05%) and group B (104.81 ± 16.79%) versus control (118.01 ± 17.61%) (P = 0.033). Moreover, maximum force was significantly lower in group A (0.17 ± 0.05 N) than in the control group (0.20 ± 0.06 N), while it was significantly higher in group B (0.22 ± 0.07 N) than in group A (P = 0.026). In conclusion, for patients on warfarin, the centrifugation time should be increased to 18 min in order to obtain PRF with superior performance.

Cyanoacrylate glue in socket repair: a comparative study.

This study aimed to compare socket repair with Nylon 5-0 suture and closure using cyanoacrylate biological glue after tooth extraction. Twenty male Wistar rats, each weighing approximately 200 g were submitted to the extraction of the right and left first molar teeth. On the right side, the alveolus was closed with 2 ethyl-cyanoacrylate glue, whereas on the left side closure was with a single interrupted Nylon 5-0 suture (Ethilon). The animals were sacrificed after 3, 7, 15, and 30 postoperative days, and images of histological sections of the alveolus were captured for analysis. Histomorphometry was performed using Image J software to quantify bone neoformation in the alveolus. The results showed that on the seventh postoperative day the side treated with 2-ethyl-cyanoacrylate presented a delay in relation to the sutured side. However, on days 15 and 30, the difference in bone neoformation between gradually decreased until the thirtieth postoperative day, with no significant difference in bone neoformation in the last period of analysis. There was no difference between neoformation in the two sides (p = 0.902) after statistical analysis of the histomorphometric results. In conclusion, socket repair after alveolus closure with 2-ethyl-cyanoacrylate allows complete bone neoformation after tooth extraction, and there is no significant difference when compared with closure with Nylon 5-0.

Evaluation of bone texture imaging parameters on panoramic radiographs of patients with Sheehan's syndrome: a STROBE-compliant case-control study.

Sheehan's syndrome (SHS) is a rare condition related to the risk of osteoporosis and evaluation of bone texture imaging features on panoramic radiographs would be suitable for this condition, which was the aim of the present study. Fractal dimension, lacunarity, and trabecular morphologic aspects were significantly altered in these patients. INTRODUCTION: SHS is an important public health problem particularly in developing countries. It is characterized as postpartum hypopituitarism secondary to obstetric complications-related ischemic pituitary necrosis that shows significant systemic metabolic repercussions. Thus, this study aimed to evaluate bone texture parameters in digital panoramic radiographs of patients with SHS. METHODS: A case-control study was conducted with 30 SHS patients from an Endocrinology and Diabetology Service of reference in Brazil, and 30 age- and sex-matched healthy controls. A custom computer program measured fractal dimension, lacunarity, and some morphologic features in the following mandibular regions of interest (50 × 50 pixels): below the mental foramen (F1), between the first and second molars (M1), and at the center of the mandibular ramus (R1). RESULTS: The fractal analysis showed a statistically significant difference between the studied groups in all regions of interest. The fractal dimension in F1 (p = 0.016), M1 (p = 0.043), and R1 (p = 0.028) was significantly lower in SHS group, as well as lacunarity in R1 (p = 0.008). Additionally, several morphologic features were statistically significant in the SHS group (p < 0.05). CONCLUSION: Therefore, individuals with SHS showed altered imaging texture parameters on panoramic radiographs, which reflect a smaller spatial organization of the bone trabeculae and, possibly, a state of reduced mineral bone density.

Preemptive analgesia-related gene and protein expression in third molar surgeries under non steroidal anti-inflammatory drug protocols: A PROSPERO-registered systematic review of clinical studies.

BACKGROUND: This study aimed to review trans lational studies focusing on third molar removal surgeries through a systematic analytical approach. MATERIAL AND METHODS: A PROSPERO-registered systematic review (CRD42017060455) was conducted following the PRISMA statement to summarize current knowledge on gene expression in third molar surgeries. A search was performed in PubMed's Medline and Scopus databases, without date or language restrictions, using the logical expression {[(Third molar) OR (preemptive) OR (cyclooxygenase inhibitors) OR (acute inflammation) AND (gene expression)]}. RESULTS: All studies included in the analysis evaluated gene expression in a third molar extraction model, using the preemptive analgesia methodology in seven investigations. The sample analyzed was obtained from gingival tissue biopsy (n=4), blood (n=1), transudate (n=1) and gingival tissue biopsy/transudate (n=1). There were differences with respect to evaluated genes, drug protocol, sample studied, and method for evaluating gene expression. CONCLUSIONS: Third molar surgeries were found to be associated with different COX-related gene expression patterns. Although inflammatory events following the surgical procedure are associated with COX isoforms, data from preemptive analgesia studies are scarce, especially from studies correlating gene expression and clinical parameters. In the future, from a clinical perspective, identifying the molecular targets of a drug based on individual gene expression may be helpful to delineate specific third molar, surgery-related, preemptive analgesia protocols.

Effect of pre-emptive analgesia on clinical parameters and tissue levels of TNF-α and IL-1ß in third molar surgery: a triple-blind, randomized, placebo-controlled study.

This study aimed to evaluate whether pre-emptive analgesia modifies the tissue expression of tumour necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1ß), and whether there is an association with postoperative surgical outcomes. A triple-blind, randomized, placebo-controlled study of patients undergoing mandibular third molar removal was performed. Volunteers were allocated randomly to receive etoricoxib 120 mg, ibuprofen 400 mg, or placebo 1h before surgery. Twenty-four surgical sites per group were required (95% confidence level and 80% statistical power). Pain scores differed significantly between groups (P<0.001). Etoricoxib and ibuprofen reduced pain scores compared to placebo (P<0.05). Pain scores peaked at 4h postoperative in the experimental groups, but at 2h postoperative in the placebo group (P<0.05). A significant reduction in TNF-α concentration from time 0' to time 30' was seen for ibuprofen (P=0.001) and etoricoxib (P=0.016). The ibuprofen group showed a significant reduction in IL-1ß levels from time 0' to time 30' (P=0.038). In conclusion, TNF-α and IL-1ß levels and the inflammatory events in third molar surgery were inversely associated with the degree of cyclooxygenase 2 selectivity of the non-steroidal anti-inflammatory drugs used pre-emptively. Patients given pre-emptive analgesia showed significant reductions in the clinical parameters pain, trismus, and oedema when compared to the placebo group.

Immune cell profile of dental pulp tissue treated with zoledronic acid.

AIM: To characterize the pulp immune cell profile in the teeth of rats treated with zoledronic acid (ZA). METHODOLOGY: Male Wistar rats (n = 6 per group) received four intravenous infusions of ZA at doses of 0.04, 0.20 or 1.00 mg kg-1 ZA or saline (control). On the 70th experimental day, they were euthanized. The first right molar was examined microscopically and submitted to toluidine blue reaction and immunohistochemical for CD68, tumour necrosis Factor (TNF)-α, interleukin (IL)-1ß, inducible nitric oxide synthase (iNOS), nuclear factor kappa B (NF-kB) and IL-18 binding protein (IL-18 bp). The presence of ectasic/dilated vessels and inflammatory cells was analysed, and mast cells and mononuclear CD68-positive cells were counted along with the intensity of immunostaining (0-3) for inflammatory markers in odontoblasts and nonodontoblasts pulp cells. The Kruskal-Wallis/Dunn's test (scores or quantitative data) and the chi-squared test (categorical data) were used (GraphPad Prism 5.0, P < 0.05). RESULTS: There was no differences in the number of animals exhibiting dilated/ectasic blood vessels (P = 0.242) and inflammatory cells (P = 0.489) or in the number of mast cells (P = 1.000). However, there was an increase in mononuclear CD68-positive cells (P = 0.026), immunostaining of TNF-α (P = 0.020), IL-1ß (P = 0.027) and iNOS (P = 0.001) in odontoblasts, and IL-1ß (P = 0.013) in nonodontoblast pulp cells dose-dependently. NFkB (nucleus and cytoplasm) and IL-18 bp did not differ between groups. CONCLUSION: ZA modified the immune cell profile in the dental pulp, increasing the number of macrophages and expression of pro-inflammatory markers independent of NFkB.

Evaluation of the p-AKT, p-JNK and FoxO3a function in oral epithelial dysplasia.

OBJECTIVES: To evaluate the expression of p-AKT, p-JNK, FoxO3a, and Ki-67 in samples of oral squamous cell carcinoma (OSCC) and oral epithelial dysplasias (OEDs) to understand their possible involvement in the malignant transformation process of oral lesions. MATERIALS AND METHODS: Tissue samples of 20 cases of OSCCs, 20 OEDs, and normal oral mucosa were subjected to immunohistochemistry reactions for anti-p-AKT, anti-p-JNK, anti-FoxO3a, and anti-Ki-67 antibodies. It was analyzed using quantitative (number of immunostained cells) and qualitative (immunostaining intensity) parameters in different cell immunostaining sublocations. RESULTS: Nuclear p-AKT was observed significantly greater immunostaining in OSCC (21.2 ± 19.0) than in dysplasias (7.9 ± 8.1) and controls (1.8 ± 4.7) (P = 0.002). Immunostaining of strong nuclear p-JNK was greater in controls (48.3 ± 13.7) than in OEDs (11.0 ± 10.3) and OSCCs (1.1 ± 1.3) (P < 0.001). Strong nuclear immunostaining of FoxO3a proved to be absent in OSCCs (0.0 ± 0.1) with little staining on dysplasias (3.2 ± 5.4) and increased expression in controls (13.5 ± 4.8) (P < 0.001). Immunostaining of strong nuclear Ki-67 was grater in OSCCs (48.1 ± 49.6) than in OED (11.8 ± 10.6) and controls (1.9 ± 2.0) (P < 0.001). CONCLUSIONS: Malignant process of OEDs in this research may involve the same mechanisms of established malignant lesions.

Immune cellular profile of bisphosphonate-related osteonecrosis of the jaw.

OBJECTIVES: Characterize the cell profile and immunostaining of proinflammatory markers in an experimental model of bisphosphonate-related osteonecrosis of the jaw (BRONJ). MATERIALS AND METHODS: Male Wistar rats (n = 6-7) were treated chronically with saline solution or zoledronic acid (ZA) at 0.04, 0.20, and 1.00 mg kg(-1) (1.4 × 10(-7) , 6.9 × 10(-6) , and 3.4 × 10(-5)  mol kg(-1) ), and subsequently, the first left inferior molar was extracted. Were performed counting of viable and empty osteocyte lacunae, viable and apoptotic osteoclasts, polymorphonuclear neutrophil, mast cells (toluidine blue), and the positive presence cells for CD68, tumor necrosis factor-alpha (TNF-α), IL (interleukin)-1ß, inducible nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-kB) and IL-18 binding protein (IL-18 bp). RESULTS: BRONJ was showed in ZA treated with 0.20 and 1.00 mg kg(-1) . There is a dose dependent increase in percentage of empty osteocyte lacunae (P < 0.001) and apoptotic osteoclasts (P < 0.001), counting of total osteoclasts (P = 0.003), polymorphonuclear neutrophil cells (P = 0.009), cytoplasmic-positive cells of CD68 (P < 0.001), TNF-α (P = 0.001), IL-1ß (P = 0.001), iNOS (P < 0.001), NF-kB (P = 0.006), and nuclear-positive cells of NF-kB (P = 0.011). Consequently, there is no difference in mast cells (P = 0.957), and IL-18 bp immunostaining decreases dose dependently (P = 0.005). CONCLUSIONS: BRONJ is characterized by increases in immunostaining for proinflammatory markers and NF-kB and inversely associated with cells exhibiting IL-18 bp.