Ozone therapy improves early stages of osseointegration in ovariectomized rats.

OBJECTIVE: the aim of this study was to analyze the influence of ozone therapy (OZN) on peri-implant bone repair in critical bones by installing osseointegrated implants in the tibia of ovariectomized rats. METHODOLOGY: ovariectomy was performed on 30 Wistar rats, aged six months (Rattus novergicus), and, after 90 days, osseointegrated implants were installed in each tibial metaphysis. The study groups were divided into the animals that received intraperitoneal ozone at a concentration of 700 mcg/kg - OZ Group (n=15) - and a control group that received an intraperitoneal saline solution and, for this reason, was named the SAL group (n=15). The applications for both groups occurred during the immediate post-operative period on the 2nd, 4th, 6th, 8th, 10th, and 12th day post-surgery. At various stages (14, 42, and 60 days), the animals were euthanized, and tests were performed on their tibiae. These tests include histomorphometric and immunohistochemical analyses, computerized microtomography, sampling in light-cured resin for calcified sections, and confocal microscopy. The obtained data were then analyzed using One-way ANOVA and the Shapiro-Wilk, Kruskal-Wallis, and student t-tests (P<0.05). RESULTS: our findings indicate that the OZ group (3.26±0.20 mm) showed better cellular organization and bone neoformation at 14 days (SAL group, 0.90±1.42 mm) (P=0.001). Immunohistochemistry revealed that osteocalcin labeling was moderate in the OZ group and mild in the SAL group at 14 and 42 days post-surgery. The data from the analysis of calcified tissues (microtomography, histometric, and bone dynamism analysis) at 60 days showed no statistically significant differences between the groups (P=0.32). CONCLUSION: it was concluded that ozone therapy anticipated the initial phases of the peri-implant bone repair process.

Evaluation of Porcine Collagen Membranes Used with Guided Bone Regeneration for Critical Defects: A Histological, Histomorphometric, Immunohistochemical, and Inflammatory Profile Analysis.

OBJECTIVE: The objective of this study was to compare the effectiveness of two porcine collagen membranes of different origin used for guided bone regeneration procedures. MATERIALS AND METHODS: Resorbable collagen membrane from porcine dermis (Bio-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) and resorbable collagen membrane from porcine pericardium (Jason, Institut Straumann AG, Peter Merian-Weg, Switzerland) were evaluated; histological, histometric, immunohistochemical, and inflammatory profile analyses were performed. The study was carried out on critical defects created in the calvaria of 72 rats (Rattus norvegicus albinus, Wistar variety) divided into three groups: coagulum group (Co), porcine pericardium group (JS), and porcine collagen group (BG). The defects were filled with clot, over which the membranes were placed. The animals were euthanized 7, 15, 30, and 60 days after surgery. STATISTICAL ANALYSIS: The Shapiro-Wilk test was used to assess data distribution. Analysis of variance (ANOVA) and the Bonferroni multiple comparison test were used to compare the differences across the mean values of the variables. Nonparametric tests, Mann-Whitney and Wilcoxon W, were used for the quantitative analysis of the inflammatory profile. A significance level of 5% (p < 0.05) was adopted with a confidence interval of 95%. SPSS software version 2.0 was used. RESULTS: A total of 1,008 analyses were performed on 288 histological slides. It was noted that both types of collagen membranes used in this study were effective for the guided bone regeneration procedure, with a greater proportion and thickness of bone formation among recipients of the BG (735 points, p = 0.021). This membrane also had greater permeability (62.25). The animals in the JS group, which received the porcine pericardial membrane, showed early and accelerated bone formation from early bone tissue, milder osteopontin and osteocalcin levels, and greater inflammatory reaction (86.4). CONCLUSION: The collagen membrane from porcine dermis demonstrated a more orderly and physiological repair process, while the porcine pericardial membrane presented a more accelerated repair process that did not remain constant over time.

Ozone therapy improves early stages of osseointegration in ovariectomized rats

Abstract Objective the aim of this study was to analyze the influence of ozone therapy (OZN) on peri-implant bone repair in critical bones by installing osseointegrated implants in the tibia of ovariectomized rats. Methodology ovariectomy was performed on 30 Wistar rats, aged six months (Rattus novergicus), and, after 90 days, osseointegrated implants were installed in each tibial metaphysis. The study groups were divided into the animals that received intraperitoneal ozone at a concentration of 700 mcg/kg — OZ Group (n=15) — and a control group that received an intraperitoneal saline solution and, for this reason, was named the SAL group (n=15). The applications for both groups occurred during the immediate post-operative period on the 2nd, 4th, 6th, 8th, 10th, and 12th day post-surgery. At various stages (14, 42, and 60 days), the animals were euthanized, and tests were performed on their tibiae. These tests include histomorphometric and immunohistochemical analyses, computerized microtomography, sampling in light-cured resin for calcified sections, and confocal microscopy. The obtained data were then analyzed using One-way ANOVA and the Shapiro-Wilk, Kruskal-Wallis, and student t-tests (P<0.05). Results our findings indicate that the OZ group (3.26±0.20 mm) showed better cellular organization and bone neoformation at 14 days (SAL group, 0.90±1.42 mm) (P=0.001). Immunohistochemistry revealed that osteocalcin labeling was moderate in the OZ group and mild in the SAL group at 14 and 42 days post-surgery. The data from the analysis of calcified tissues (microtomography, histometric, and bone dynamism analysis) at 60 days showed no statistically significant differences between the groups (P=0.32). Conclusion it was concluded that ozone therapy anticipated the initial phases of the peri-implant bone repair process.

What are the Consequences of Incorrect Handling in the Treatment of Blunt-Cut Lip Injuries?

This study aimed report two cases of blunt-cut lip injury which occurred in postoperatory dehiscence. Patients were referred to the emergence attendance and the clinical examination revealed extensive laceration on the upper and lower lips of both patients, highly contaminated with asphalt residue. The affected regions were properly cleaned with saline and antiseptic solution, and, under local anesthesia, suturing was performed in layers in the muscle and oral mucosa region with 4-0 resorbable thread and in the skin region with 6-0 non-absorbable thread. Patients presented different levels of dehiscence on post-operatory evaluation. Thus, it was prescribed antibiotic and healing ointments for decontamination and improvement of the healing process. Third days post-operatory one of the patients presented a great healing of external lips and vermilion lip. However, the other patient presented aesthetic sequelae in the vermilion region of the lip, with a line of fibrosis and misalignment in the region, but not function sequelae. Thus, it was concluded that blunt injuries on the lip must strictly follow the established treatment protocols and must begin aiming for favorable results in the first intervention. Moreover, the postoperative care of the patient and the surgeon are as important as the procedure itself.

Calvaria Critical Size Defects Regeneration Using Collagen Membranes to Assess the Osteopromotive Principle: An Animal Study.

Guided bone regeneration (GBR) is a common practice in implantology, and it is necessary to use membranes in this process. The present study aimed to evaluate the osteopromotive principle of two porcine collagen membranes in critical-size defects at rats calvaria. Ninety-six Albinus Wistar rats were divided into BG (positive control), JS, CS, and CG (negative control) groups and were sacrificed at 7, 15, 30, and 60 days postoperatively. The samples were assessed by histological, histometric, immunohistochemical, and microtomographic analyses. More intense inflammatory profile was seen in the JS and CS groups (p < 0.05). At 60 days, the JS group showed a satisfactory osteopromotive behavior compared to BG (p = 0.193), while CS did not demonstrate the capacity to promote bone formation. At the immunohistochemical analysis, the CS showed mild labeling for osteocalcin (OC) and osteopontin (OP), the JS demonstrated mild to moderate for OC and OP and the BG demonstrated moderate to intense for OC and OP. The tridimensional analysis found the lowest average for the total volume of newly formed bone in the CS (84,901 mm2), compared to the BG (319,834 mm2) (p < 0.05). We conclude that the different thicknesses and treatment techniques of each membrane may interfere with its biological behavior.

Do the New Protocols of Platelet-Rich Fibrin Centrifugation Allow Better Control of Postoperative Complications and Healing After Surgery of Impacted Lower Third Molar? A Systematic Review and Meta-Analysis.

PURPOSE: Platelet concentrate generation protocols have undergone several modifications in recent years; in light of these new developments, this study review aims to evaluate the effects of platelet-rich fibrin (PRF) and the new centrifugation protocols, advanced platelet-rich fibrin (A-PRF), and leukocyte platelet-rich fibrin (L-PRF), after extraction of impacted mandibular third molar. Specifically, we assessed pain control, edema, trismus, and soft tissue healing, and also measured the degree of periodontal regeneration adjacent to the second molar. METHODS: PubMed, MEDLINE, EMBASE, Web of Science, Virtual health library (BVS), and Cochrane Library were searched up to Julye 2021; randomized controlled studies were included. This report followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and PICO (population, intervention, comparison, outcome) questions. This review has been registered at the International Prospective Register of Ongoing Systematic Reviews (PROSPERO) under the number CRD42019136701. The risk of bias screening and data extraction was performed according to the guidelines recommended by Cochrane. The quantitative analysis was performed using RevMan version 5.4. RESULTS: Of 17 studies included in the systematic review, 11 were eligible for the meta-analysis. The use of L-PRF was not associated with better soft tissue healing at day 7. (standard mean difference = -0.70; 95% confidence interval, -3.50 to 2.10; Z = 0.49; P = .62; heterogeneity = 0.00001; I2 = 97%). With L-PRF, qualitative analysis revealed better pocket depth and insertion level, and also better pain control at 1 and 3 days. With A-PRF, a lower consumption of analgesics was observed than with L-PRF. With both A-PRF and L-PRF, better control of edema (but not trismus) was observed. CONCLUSIONS: The use of L-PRF and A-PRF allows better control of pain and edema compared with the use of standard PRF protocols, but neither has an effect on trismus. The PRF and L-PRF protocols improve soft tissue healing, although not to a statistically significant degree; however, they could improve probing depth at the third month after third molar surgery.

Mapping Bone Marrow Cell Response from Senile Female Rats on Ca-P-Doped Titanium Coating.

Chemical and topographical surface modifications on dental implants aim to increase the bone surface contact area of the implant and improve osseointegration. This study analyzed the cellular response of undifferentiated mesenchymal stem cells (MSC), derived from senile rats' femoral bone marrow, when cultured on a bioactive coating (by plasma electrolytic oxidation, PEO, with Ca2+ and P5+ ions), a sandblasting followed by acid-etching (SLA) surface, and a machined surface (MSU). A total of 102 Ti-6Al-4V discs were divided into three groups (n = 34). The surface chemistry was analyzed by energy dispersive spectroscopy (EDS). Cell viability assay, gene expression of osteoblastic markers, and mineralized matrix formation were investigated. The cell growth and viability results were higher for PEO vs. MSU surface (p = 0.001). An increase in cell proliferation from 3 to 7 days (p < 0.05) and from 7 to 10 days (p < 0.05) was noted for PEO and SLA surfaces. Gene expression for OSX, ALP, BSP, and OPN showed a statistical significance (p = 0.001) among groups. In addition, the PEO surface showed a higher mineralized matrix bone formation (p = 0.003). In conclusion, MSC from senile female rats cultured on SLA and PEO surfaces showed similar cellular responses and should be considered for future clinical investigations.

Single-Dose Ibuprofen-Arginine as a Preventive for Pain, Edema, and Trismus After Impacted Lower Third Molar Surgery: A Randomized Split-Mouth Clinical Trial.

OBJECTIVE: We examined if the association of ibuprofen with arginine has a better anti-inflammatory effect on pain, edema, and trismus after surgery of the impacted mandibular third molar than ibuprofen alone. MATERIALS AND METHODS: The study included 21 patients, 18 to 30 years of age, each with an impacted, and bilateral and symmetric third molar (total n = 21) that required transalveolar extraction. Patients were randomly assigned numbers from 1 to 21. Group A received ibuprofen-arginine as preoperative medication, while Group B received only ibuprofen. Both groups received the same postoperative medications: amoxicillin + acetaminophen. All patients were evaluated for pain at 6, 12, and 24 hours. They were evaluated for edema and trismus before surgery; immediately after surgery; and at 24, 48, and 72 hours postoperatively. Postoperative pain scores used the visual analog scale (BS-11). For facial edema and trismus, linear measurements used the method modified by Gabka and Matsumura. STATISTICAL ANALYSIS: For the evaluation of data between Group A and Group B, we used the statistical software SPSS version 22. The Shapiro-Wilk, analysis of variance, the Bonferroni comparisons, and the Wilcoxon test were used. All tests were based on a significance level of 0.05. RESULTS: The study results reveal that the facial edema scores of Group A and Group B presented statistically significant differences (p < 0.05), while for postoperative trismus, there was no statistically significant difference (p > 0.05) between the scores of Group A and Group B. CONCLUSION: As a conclusion, we can state that the use of ibuprofen-arginine allows for significantly better control of pain and edema, and shows a tendency toward better recovery from trismus, although without statistical significance. Based on this, we can assert that arginine improves the anti-inflammatory power of ibuprofen, thus generating better tissue healing after surgery of the impacted third molar.

Application of Tissue Engineering in Manufacturing Absorbable Membranes to Improve the Osteopromoting Potential of Collagen.

The membranes are an important biomaterial that contribute to osteopromotion. This study aimed to evaluate the osteopromotive potential of collagen membranes associated with Hydroxyapatite (HA) in critical size calvaria rat's defects. Ninety-six Albinus Wistar rats were divided into four groups: (CG) negative control: clot only (CG); positive control: porcine collagen membrane (BG); fish collagen membrane associated with HA (CP); bovine collagen membrane associated with HA (CB), analyzed at 7, 15, 30, and 60 postoperative days. At 30 days, membrane integrity was observed in the CB and fragments in the CP and BG groups were dispersed in the center of the defect. At 60 days, BG demonstrated better results with no statistical difference for the CP group (p = 0.199) and a statistically significant difference for the CB group (p = 0.013). The inflammatory profiles of the BG and CP groups were similar. Immunohistochemistry demonstrated at 60 days moderate osteopontin staining for the BG and CP groups, light staining for the CB, and intense osteocalcin staining for the BG, while the CB and CP groups demonstrated moderate staining. Microtomography revealed the highest mean bone volume (14.247 mm3) in the BG, followed by the CB (11.850 mm3), and CP (9.560 mm3) group. The collagen membranes associated with HA demonstrated an osteopromotive potential.

A triple-blind randomized clinical trial of different associations between dexamethasone and non-steroids anti-inflammatories for preemptive action in third molar extractions.

The aim of this study is to evaluate the preemptive analgesic effects of dexamethasone (DEX) alone or combined with non-steroidal anti-inflammatory drugs (NSAIDs) in third molar surgeries. The subjects were divided into five groups (n = 20 teeth/group); subjects received only 8 mg of dexamethasone 1 h before the surgical procedure (DEX group), or in combination with etodolac (DEX + ETO), ketorolac (DEX + KET), ibuprofen (DEX + IBU), loxoprofen (DEX + LOX). Paracetamol 750 mg was provided as the number of rescue analgesics (NRA). Salivary PGE2 expression was measured preoperatively and at 48 h. Edema and Maximum mouth opening (MMO) were measured postoperatively at 48 h and 7 days. A visual analog scale (VAS) was performed postoperatively at 6, 12, 24, 48, 72 h, and 7 days. Salivary expression of PGE2 showed a decrease only for the DEX group. Edema and MMO and NRA consumption showed no significant differences among the groups (P > 0.05). The VAS showed a significantly lower pain perception at 6 h after the surgery for the DEX + ETO and DEX + KET groups (P < 0.05). The combination of DEX and NSAIDS should be considered for preemptive acute postsurgical pain management in third molar surgery. In some drug associations such as dexamethasone 8 mg + NSAIDS (ETO and KET) in the pre-operative time, only a few rescue analgesics are necessary.

Evaluation of Guided Bone Regeneration in Critical Defects Using Bovine and Porcine Collagen Membranes: Histomorphometric and Immunohistochemical Analyses.

Guided bone regeneration (GBR) is a technique used to facilitate bone regeneration, which uses a biocompatible membrane acting as a physical barrier to prevent the adjacent connective tissue from invading the bone defect. The aim of this study was to evaluate and compare the effectiveness of bovine and porcine collagenous membranes as barriers to connective tissue invasion during the repair of critical bone defects in rat calvaria, using histological, histometric, and immunohistochemical analyses. For this study, 72 rats were divided into three groups: clot group (CG), bovine collagen group (BCG), and porcine collagen group (PCG). Analyses were performed on days 7, 15, 30, and 60. The histological results showed that the PCG exhibited bone neoformation starting from day 7, and after 30 days of repair, the surgical defect was completely filled in some animals. For the BCG, there was little bone neoformation activity in the initial periods, and from day 30 onwards, there was an increase in bone neoformation, with a greater increase on day 60. The data obtained in the histometric analysis reveal that, on day 30, the neoformed bone area did not vary greatly between the PCG and the BCG, though both varied from the CG. By day 60, the PCG presented a greater area of neoformation than the BCG. These results were corroborated by the immunohistochemistry results. In view of the results obtained, it can be concluded that all membranes studied in this research promoted GBR.

The efficacy of etodolac and ibuprofen, regarding gender, on pain, edema and trismus after impacted lower third molar surgery: A randomized prospective clinical split-mouth study / La eficacia del etodolaco y del ibuprofeno, según el sexo, sobre el dolor, el edema y trismo después de la cirugía del tercer molar inferior impactado: un estudio prospectivo aleatorizado estudio clínico de boca dividida

Background: This study aimed to conduct a randomized prospective study about the efficacy of etodolac andibuprofen on trismus, pain and edema regarding gender of patients submitted to impacted lower third molar teethextraction.Material and Methods: Thirty patients aging between 16 and 35 year-old were submitted to the exodontia of im-pacted lower third molars. During the postoperative period, patients received nine ibuprofen (600 mg) or etodolac(300 mg) pills via oral administration immediately after surgery and repeated doses every eight hours during threedays. Patients were evaluated regarding pain, trismus and edema.Results: Sixteen men and fourteen women participated of the study. No statistical difference was establishedregarding gender according to the evaluated parameters. However, etodolac use showed better results regardingpain, trismus and edema.Conclusions: Pain, edema and trismus after impacted third molars extraction were not influenced by gender.(AU)

Bone Regeneration Assessment of Polycaprolactone Membrane on Critical-Size Defects in Rat Calvaria.

Biomaterials for use in guided bone regeneration (GBR) are constantly being investigated and developed to improve clinical outcomes. The present study aimed to comparatively evaluate the biological performance of different membranes during the bone healing process of 8 mm critical defects in rat calvaria in order to assess their influence on the quality of the newly formed bone. Seventy-two adult male rats were divided into three experimental groups (n = 24) based on the membranes used: the CG-membrane-free control group (only blood clot, negative control), BG-porcine collagen membrane group (Bio-Guide®, positive control), and the PCL-polycaprolactone (enriched with 5% hydroxyapatite) membrane group (experimental group). Histological and histometric analyses were performed at 7, 15, 30, and 60 days postoperatively. The quantitative data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). At 7 and 15 days, the inflammatory responses in the BG and PCL groups were significantly different (p < 0.05). The PCL group, at 15 days, showed a large area of newly formed bone. At 30 and 60 days postoperatively, the PCL and BG groups exhibited similar bone healing, including some specimens showing complete closure of the critical defect (p = 0.799). Thus, the PCL membrane was biocompatible, and has the potential to help with GBR procedures.

Combination of etodolac and dexamethasone improves preemptive analgesia in third molar surgery: a randomized study.

OBJECTIVE: This randomized, controlled, triple-blind, crossover clinical trial aimed to investigate the use of dexamethasone (DEX) and etodolac (ETO) as preemptive analgesia before mandibular third molar extraction. METHODS: Patients were divided into three groups (n = 20 teeth each) based on the drug administered: DEX 8 mg (DEX); DEX 8 mg plus ETO 300 mg (DEX + ETO), and ETO 300 mg (ETO). Paracetamol (750 mg) tablets were administered as rescue analgesics. Pain was evaluated using the visual analog scale (VAS) at 6, 12, 24, 48, and 72 h and 7 days postoperatively. Edema and trismus were assessed 48 and 72 h postoperatively. All data were subjected to statistical analysis, where a P value < .05 indicated statistical significance. RESULTS: VAS scores and the number of rescue analgesics taken were lower in the DEX + ETO group than in the other groups (P < .001 and P = .014, respectively). At 48 h, trismus was similar among all groups; however, the ETO group showed the highest trismus 7 days postoperatively (P < .05). Edema was similar among all groups at all time points (P > .05). CONCLUSION: The combined use of the anti-inflammatory drugs, DEX and ETO, resulted in better pain control and the need for fewer rescue analgesics than the use of either drug alone, which indicated their effectiveness in mandibular third molar extractions preoperatively. CLINICAL RELEVANCE: This drug combination can lead to less pain, edema, and trismus and reduce the use of rescue analgesics in the postoperative period.

Gene expression, immunohistochemical and microarchitectural evaluation of bone formation around two implant surfaces placed in bone defects filled or not with bone substitute material.

OBJECTIVE: The aim of this study is to evaluate through gene expression, immunohistochemical and microtomographic (micro-CT) analysis the response of peri-implant bone tissue around titanium implants with different surface treatments, placed in bone defects filled or not with bone substitute materials. In addition, to investigate the hypothesis that porous-hydrophilic surface induces a faster bone formation. MATERIALS AND METHODS: Twenty-six animals were divided into two groups according to implant surface treatment. In each tibia, a bone defect was created followed by the placement of one implant. On the left tibia, the defect was filled with blood clot (BC), and on the right tibia, the defect was filled with biphasic hydroxyapatite/ß-tricalcium-phosphate (HA/TCP) generating four subgroups: BC-N: bone defect filled with blood clot and porous surface titanium implant installed; BC-A: bone defect filled with blood clot and porous-hydrophilic surface titanium implant installed; HA/TCP-N: bone defect filled with bone substitute material and porous surface titanium implant installed; and HA/TCP-A: bone defect filled with bone substitute material and porous-hydrophilic surface titanium implant installed. The animals were submitted to euthanasia at 15, 30, and 60 days after implant installation. The expression of two genes was evaluated: RUNX2 and BSP. Immunohistochemical analyses were performed for detection of RUNX2, OPN, OCN, OPG, and RANKL antibodies and bone matrix proteins. Finally, four parameters were chosen for micro-CT analysis: trabecular number, separation and thickness, and connectivity density. RESULTS: Descriptive analysis showed similar findings among the experimental groups. Moreover, porous-hydrophilic surfaces presented a higher expression of RUNX2, which is probably an indicative of better osteogenesis; although the data from this study may be considered an insufficient support for a concrete statement. CONCLUSION: Porous hydrophilic surface can improve and accelerate protein expression and bone formation.

Evaluation of Osteoconduction of a Synthetic Hydroxyapatite/ß-Tricalcium Phosphate Block Fixed in Rabbit Mandibles.

(1) Background: This study aimed to evaluate the incorporation of hydroxyapatite/ß-tricalcium phosphate blocks grafted in rabbit mandibles. (2) Methods: Topographic characterization of biomaterial was performed through scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX). Ten rabbits randomly received autogenous bone graft harvested from the tibia (Autogenous Group-AG) or synthetic biomaterial manufactured in ß-tricalcium phosphate (Biomaterial Group-BG) at their right and left mandibular angles. Euthanasia was performed at 30 and 60 postoperative days; (3) Results: SEM-EDX showed a surface with the formation of crystals clusters. Histological analyses in BG at 30 days showed a slower process of incorporation than AG. At 60 days, BG showed remnants of biomaterial enveloped by bone tissue in the anabolic modeling phase. Histometric analysis showed that mean values of newly formed bone-like tissue in the AG (6.56%/9.70%) were statistically higher compared to BG (3.14%/6.43%) in both periods, respectively. Immunohistochemical analysis demonstrated early bone formation and maturation in the AG with more intense osteopontin and osteocalcin staining. (4) Conclusions: The biomaterial proved to be a possible bone substitute, being incorporated into the receiving bed; however, it showed delayed bone incorporation compared to autogenous bone.

Is the Bacterial Cellulose Membrane Feasible for Osteopromotive Property?

Guided bone regeneration was studied to establish protocols and develop new biomaterials that revealed satisfactory results. The present study aimed to comparatively evaluate the efficiency of the bacterial cellulose membrane (Nanoskin®) and collagen membrane Bio-Gide® in the bone repair of 8-mm critical size defects in rat calvaria. Seventy-two adult male rats were divided into three experimental groups (n = 24): the CG-membrane-free control group (only blood clot, negative control), BG-porcine collagen membrane group (Bio-Guide®, positive control), and BC-bacterial cellulose membrane group (experimental group). The comparison periods were 7, 15, 30, and 60 days postoperatively. Histological, histometric, and immunohistochemical analyses were performed. The quantitative data were subjected to 2-way ANOVA and Tukey's post-test, and p < 0.05 was considered significant. At 30 and 60 days postoperatively, the BG group showed more healing of the surgical wound than the other groups, with a high amount of newly formed bone (p < 0.001), while the BC group showed mature connective tissue filling the defect. The inflammatory cell count at postoperative days 7 and 15 was higher in the BC group than in the BG group (Tukey's test, p = 0.006). At postoperative days 30 and 60, the area of new bone formed was greater in the BG group than in the other groups (p < 0.001). Immunohistochemical analysis showed moderate and intense immunolabeling of osteocalcin and osteopontin at postoperative day 60 in the BG and BC groups. Thus, despite the promising application of the BC membrane in soft-tissue repair, it did not induce bone repair in rat calvaria.

Osteopromotion Capacity of Bovine Cortical Membranes in Critical Defects of Rat Calvaria: Histological and Immunohistochemical Analysis.

Membranes that aid the guided bone regeneration (GBR) process have been the subject of studies of compatible biomaterials that contribute to this repair process. The present study compared different membranes used in critical-size defects of rat calvaria by assessing GBR as well as histological, histomorphometric, and immunohistochemical reactions. Forty-eight male albino Wistar rats were randomly allocated into four groups (n = 12 each), namely, C: membrane-free control group (only blood clot, negative control group); BG: porcine collagen membrane group (Bio-Gide®, positive control group); GD: bovine cortical membrane group (first experimental group); and GDF: thicker bovine cortical membrane group (second experimental group). Rats were euthanized at 30 and 60 days postoperatively. Quantitative data from the histometric analysis were submitted to two-way ANOVA and Tukey's posttest when p < 0.05. Histomorphometric results of the thicker bovine cortical membrane at 30 and 60 days were promising, showing improved new bone formation values (p < 0.05), and the CD group presented similar results in both analysis periods, being surpassed only by the GDF group (p < 0.05). The immunohistochemical results were associated with the histomorphometric data. A less-thick membrane also assisted in GBR. All membranes promoted GBR, especially the positive control and experimental groups.

The Effectiveness of the Low-Level Laser, Antibiotic and Surgical Therapy in the Treatment of Medication-Related Osteonecrosis of the Jaws: A Case Report.

Introduction: Bisphosphonates consist of a range of drugs used in the treatment of osteopathy or some osteotropic malignancies. Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse consequence of their use. Conventional treatment is not always effective, so it is necessary to resort to the use of adjuvant therapies. This study aimed to evaluate the effectiveness of the association of surgery, antibiotic therapy and low-level laser (LLL) therapy as a treatment strategy for MRONJ through the presentation of a clinical case. Case Presentation: A 49-year-old female patient presented for the diagnosis and treatment of bone lesions in the maxillae. The patient reported that she had used zoledronate for 1 year. Five years later there were 2 painless bone lesions on both sides of the maxilla, following the extraction of the first upper molars. Clinical, tomographic and histopathologic examination established the diagnosis of MRONJ. The treatment consisted of the curettage of the necrotic bone, antibiotic and thirteen LLL therapy sessions. Integral mucosal healing was observed after a two-month follow-up and no symptoms were detected. The patient was evaluated at 6 and 12 postoperative months without complications. Conclusion: The combination of surgery, antibiotic therapy, and LLL therapy has shown to be effective in the treatment of MRONJ.

Bone formation around two titanium implant surfaces placed in bone defects with and without a bone substitute material: A histological, histomorphometric, and micro-computed tomography evaluation.

OBJECTIVE: To evaluate the histological and microtomographic response of peri-implant bone tissue around titanium implants with different surface treatments, placed in bone defects filled or not filled with bone substitute materials. MATERIALS AND METHODS: Thirty rabbits were divided into two groups according to the implant surface treatment. A bone defect was created in both tibias of all the rabbits, followed by the placement of one implant in each of these defects. On the left tibia, the defect was filled with a blood clot (BC), and on the right tibia, the defect was filled with biphasic hydroxyapatite/ß-tricalcium-phosphate (HA/TCP); thus, there were four groups in total: BC-N: bone defect filled with a BC and porous surface titanium implant (control group); BC-A: bone defect filled with a BC and porous-hydrophilic surface titanium implant; HA/TCP-N: bone defect filled with a bone substitute material and porous surface titanium implant; HA/TCP-A: bone defect filled with a bone substitute material and porous-hydrophilic surface titanium implant. The animals were submitted for euthanasia at three distinct periods: 15, 30, and 60 days after implant installation. The samples were evaluated histologically and histometrically, to assess the quantity and quality of cells and the remaining bone substitute material in the grafted areas. The bone quantity was assessed by micro-computed tomography (CT). RESULTS: For both surface types, the presence of a bone substitute material led to higher values in all evaluated micro-CT parameters, except in the bone surface/volume ratio parameter. No significant statistical difference was found for new bone formation between the four groups (P < .05; CI 95%). At all periods, the HA/TCP-A group had a higher percentage of new bone formation. CONCLUSION: These results suggest that a porous hydrophilic surface in the presence of bone substitute material can accelerate peri-implant bone tissue formation.