The effects of intro-oral parathyroid hormone on the healing of tooth extraction socket: an experimental study on hyperglycemic rats

Abstract Objective To investigate the effects of intro-oral injection of parathyroid hormone (PTH) on tooth extraction wound healing in hyperglycemic rats. Methodology 60 male Sprague-Dawley rats were randomly divided into the normal group (n=30) and DM group (n=30). Type 1 diabetes mellitus (DM) was induced by streptozotocin. After extracting the left first molar of all rats, each group was further divided into 3 subgroups (n=10 per subgroup), receiving the administration of intermittent PTH, continuous PTH and saline (control), respectively. The intermittent-PTH group received intra-oral injection of PTH three times per week for two weeks. A thermosensitive controlled-release hydrogel was synthesized for continuous-PTH administration. The serum chemistry was determined to evaluate the systemic condition. All animals were sacrificed after 14 days. Micro-computed tomography (Micro-CT) and histological analyses were used to evaluate the healing of extraction sockets. Results The level of serum glucose in the DM groups was significantly higher than that in the non-DM groups (p<0.05); the level of serum calcium was similar in all groups (p>0.05). Micro-CT analysis showed that the DM group had a significantly lower alveolar bone trabecular number (Tb.N) and higher trabecular separation (Tb.Sp) than the normal group (p<0.05). The histological analyses showed that no significant difference in the amount of new bone (hard tissue) formation was found between the PTH and non-PTH groups (p>0.05). Conclusions Bone formation in the extraction socket of the type 1 diabetic rats was reduced. PTH did not improve the healing of hard and soft tissues. The different PTH administration regimes (continuous vs. intermittent) had similar effect on tissue healing. These results demonstrated that the metabolic characteristics of the hyperglycemic rats produced a condition that was unable to respond to PTH treatment.

The effects of luteolin nanoparticles on the healing of extracted tooth socket in rabbits

Objective: To evaluate the effects of luteolin nanoparticles on the process tooth socket healing in rabbits. Design: This study comprised five rabbits randomly assigned to control animal and experimental animals. Immediately after the extraction of an upper maxillary incisor, the alveolar sockets of experimental animals were treated with topical luteolin while alveolar sockets of the control group remained without treatment. The animals were sacrificed by decapitation with deep anesthesia seven days post tooth extraction. The tooth sockets were sectioned and stained with hematoxylin and eosin stains. Results: Histological evaluation revealed that luteolin treatment induced earlier healing of extracted tooth sockets. Conclusion: These findings suggest that luteolin accelerates the healing process in tooth sockets of rabbits.

Alveolar bone repair with strontium- containing nanostructured carbonated hydroxyapatite

ABSTRACT Objective: This study aimed to evaluate bone repair in rat dental sockets after implanting nanostructured carbonated hydroxyapatite/sodium alginate (CHA) and nanostructured carbonated hydroxyapatite/sodium alginate containing 5% strontium microspheres (SrCHA) as bone substitute materials. Methods: Twenty male Wistar rats were randomly divided into two experimental groups: CHA and SrCHA (n=5/period/group). After one and 6 weeks of extraction of the right maxillary central incisor and biomaterial implantation, 5 μm bone blocks were obtained for histomorphometric evaluation. The parameters evaluated were remaining biomaterial, loose connective tissue and newly formed bone in a standard area. Statistical analysis was performed by Mann-Withney and and Wilcoxon tests at 95% level of significance. Results: The histomorphometric results showed that the microspheres showed similar fragmentation and bio-absorbation (p>0.05). We observed the formation of new bones in both groups during the same experimental periods; however, the new bone formation differed significantly between the weeks 1 and 6 (p=0.0039) in both groups. Conclusion: The CHA and SrCHA biomaterials were biocompatible, osteoconductive and bioabsorbable, indicating their great potential for clinical use as bone substitutes.

Hyaluronic acid accelerates bone repair in human dental sockets: a randomized triple-blind clinical trial

Abstract This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.

Uso de la crema Vimang® en la cicatrización alveolar después de la extracción dentaria en un paciente con diabetes mellitus / Use of the Vimang® cream in the alveolar healing after dental extraction in a patient with diabetes mellitus

Se presenta el caso clínico de un anciano de 75 años de edad, con antecedentes de hipertensión arterial y diabetes mellitus, quien acudió a consulta estomatológica para que le extrajeran el segundo molar inferior izquierdo por presentar gran destrucción debido a caries dental. Después de concluir el proceder se le aplicó la crema Vimang® directamente en el alveolo para acelerar los procesos de cicatrización y evitar cualquier complicación inmediata o mediata; luego se indicó 4 veces al día después de cepillarse. El paciente logró la curación a los 15 días y no se detectó ninguna reacción adversa

The case report of a 75 years old man with history of hypertension and diabetes mellitus is presented. He went to the stomatological service to have the second left lower molar extracted, because it had a great destruction due to dental decay. After concluding the procedure the Vimang® cream was directly applied in the alveolus to accelerate the healing processes and avoid any immediate or mediate complication; then it was indicated 4 times a day after brushing his teeth. The patient achieved healing after 15 days and no adverse reaction was detected

Collagen sponge and rhBMP-2 improve socket healing in rats treated with zoledronic acid

Abstract The aim of the present study was to evaluate the possible use of a commercial absorbed collagen sponge and bone morphogenetic protein (BMP) for the prevention of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in rats. Twenty rats received intraperitoneal injections of 0.1-mg/kg of zoledronic acid three times a week for eight weeks before the extraction of both maxillary first molars after eight weeks. A collagen sponge (experimental group 1) and a collagen sponge with recombinant human BMP-2 (experimental group 2) were applied to the right extraction sockets of ten rats each. The 20 left extraction sockets (control groups 1 and 2) were left unprotected. After eight weeks, all rats were euthanized. Macroscopic analysis, micro-computed tomography (CT) analysis, and histological analysis were performed. There was a significant difference in the bone density between the control and experimental groups on micro-CT analysis. Impaired healing of the extraction sockets, indicating BRONJ, was observed in 80% of control group 1, 90% of control group 2, 30% of experimental group 1, and 20% of experimental group 2. The collagen sponge with/without BMP used for protecting the extraction socket had the potential for a positive effect in reducing the incidence of bisphosphonate-related osteonecrosis of the jaw in rats.

Experimental osteonecrosis: development of a model in rodents administered alendronate

Abstract The main objective of this study was to cause bisphosphonate-related osteonecrosis of the jaws to develop in a rodent model. Adult male Holtzman rats were assigned to one of two experimental groups to receive alendronate (AL; 1 mg/kg/week; n = 6) or saline solution (CTL; n = 6). After 60 days of drug therapy, all animals were subjected to first lower molar extraction, and 28 days later, animals were euthanized. All rats treated with alendronate developed osteonecrosis, presenting as ulcers and necrotic bone, associated with a significant infection process, especially at the inter-alveolar septum area and crestal regions. The degree of vascularization, the levels of C-telopeptide cross-linked collagen type I and bone-specific alkaline phosphatase, as well as the bone volume were significantly reduced in these animals. Furthermore, on radiographic analysis, animals treated with alendronate presented evident sclerosis of the lamina dura of the lower first molar alveolar socket associated with decreased radiographic density in this area. These findings indicate that the protocol developed in the present study opens new perspectives and could be a good starting model for future property design.

Cytocompatibility and biocompatibility of nanostructured carbonated hydroxyapatite spheres for bone repair

ABSTRACT Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p<0.05) indicating greater biosorption. An increase in the RANKL/OPG ratio was observed in the CHA group on the 7th day. Conclusion CHA spheres were osteoconductive and presented earlier biosorption, inducing early increases in the levels of proteins involved in resorption.

Effects of Coffee Intake and Intraperitoneal Caffeine on Bone Repair Process - A Histologic and Histometric Study

Studies have suggested that caffeine acts on bone promoting an increase of calcium excretion, inhibition of osteoblast proliferation and delay in tissue repair process, raising the risk of fractures, osteoporosis, periodontal disease and affecting the success of bone reconstructive procedures. The aim of this study was to analyze histomorphometrically the process of alveolar bone healing after tooth extraction in rats subjected to daily intake of boiled coffee or intraperitoneal administration of caffeine. Forty-five male rats were divided according to the treatment in Control group (C); Coffee group (CO) - treated with coffee since birth; and Caffeine (CAF) - intraperitoneal injection of aqueous solution of caffeine 1.5% (0.2 mL/100g body weight) for 30 days. When weighing between 250-300 g they were anesthetized, subjected to extraction of the maxillary right incisor, and euthanized 7, 21 and 42 days after surgery for histological assessments of bone volume and the quality of formed bone in the dental socket. The qualitative results demonstrated larger amounts of blood clot and immature bone in animals under treatment of pure caffeine compared to coffee and control. Histometric analysis revealed that coffee treatment led to a 40% drop in bone formation, and caffeine a 60% drop in comparison to control animals (ANOVA p≤0.01). It was concluded that both the daily ingestion of coffee and the intraperitoneal administration of caffeine in rats delayed the alveolar bone reparative process after tooth extraction, and this effect was more aggressive when pure caffeine was used.

Estudos têm sugerido que a cafeína age sobre o osso promovendo um aumento da excreção de cálcio, inibição da proliferação dos osteoblastos e retardo no processo de reparação tecidual, aumentando o risco de fraturas, osteoporose, doença periodontal, bem como afetando o sucesso de procedimentos de reconstrução óssea. O objetivo deste estudo foi analisar histomorfometricamente o processo de reparação óssea alveolar após extração dentária em ratos submetidos à ingestão diária de café fervido ou a administração intraperitoneal de cafeína. 45 ratos machos foram divididos de acordo com o tratamento, em controle (C); café (CO), tratados com café desde o nascimento; e cafeína (CAF), injeção intraperitoneal de solução aquosa de cafeína de 1,5 % (0,2 mL/100 g de peso corporal) durante 30 dias. Quando pesavam entre 250-300 g os animais foram anestesiados, submetidos à extração do incisivo superior direito, e sacrificados em 7, 21 e 42 dias após a cirurgia para análises histológicas quanto ao volume e à qualidade do osso formado no alvéolo dental. Os resultados qualitativos demonstraram grandes quantidades de coágulo sanguíneo e osso imaturo nos animais tratados com cafeína pura, em relação aos grupos café e controle. A avaliação histométrica mostrou que o tratamento com o café levou a uma queda na formação óssea de 40%, e com a cafeína de 60% em comparação ao grupo controle (ANOVA p≤0,01). Concluiu-se que tanto a ingestão diária de café quanto a administração intraperitoneal de cafeína em ratos retardou o processo de reparação do osso alveolar após extração dentária, e este efeito é mais agressivo quando do uso da cafeína pura.

Antiperoxidative properties of oil mixes of high ratio Omega-9:Omega-6 and low ratio Omega-6:Omega-3 after molar extraction in rats

PURPOSE: To evaluate the antioxidant and antiperoxidative effects of oil mixes of high ratio Omega-9:Omega-6 and low ratio Omega-6:Omega-3 in the third day after tooth extraction in rats. METHODS: Thirty-two male Wistar rats (270-310g) were randomly distributed in two groups: Control (n=24) and Test (n=8). Control group was divided into three subgroups (n=8): G1: Sham-Saline; G2: Saline; G3: Isolipid. G1 and G2 animals received NaCl 0.9% while G3 rats were treated with an isolipid mixture (alpha-linolenic acid - ALA) containing -6/-3 oils (8:1 ratio) and-9/-6 (0.4:1 ratio). Test group animals (G4) received oily mixtures (alpha-linolenic acid - ALA, docosahexaenoic acid - DHA, eicosapentaenoic acid - EPA) of -6/-3 (1.4:1 ratio) and -9/-6 (3.4:1 ratio). Saline and oils were administered by gavage during four days before and three days after first mandibular molar extraction. Following, samples (arterial blood and alveolar mucosa) were collected for glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) assays. RESULTS: Oil mixes induced a significant decrease in GSH and TBARS tissue and plasma concentrations in the third day post-surgery. CONCLUSION: Gavage administration of oil mixes of high ratio Omega-9:Omega-6 and low ratio Omega-6:Omega-3 after molar extraction in rats induces a significant decrease in lipid peroxidation. .

Cigarette smoke inhalation influences bone healing of post-extraction tooth socket: a histometric study in rats

The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7th day, CSI affected negatively (p<0.05) bone formation with respect to NMT and RA (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, for the control and test groups, respectively). In contrast, no statistically significant differences (p>0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.

O objetivo do estudo foi avaliar a influência da inalação da fumaça de cigarros (IFC) sobre os períodos iniciais de reparo ósseo alveolar. Quarenta ratos Wistar foram aleatoriamente divididos em teste: animais expostos à IFC, que se iniciou 3 dias antes das extrações mantendo-se até o sacrifício (n=20)e controle (animais que não foram expostos à IFC; n=20). Os animais tiveram seus segundos molares inferiores extraídos bilateralmente (n=5/grupo/período) e foram sacrificados nos dias 3, 7, 10 e 14 dias após a cirurgia. Imagens digitalizadas foram analisadas de acordo com os seguintes parâmetros histométricos: tecido osteóide (OT), área remanescente (RA), tecido mineralizado (MT) e tecido não mineralizado (NMT) em cada alvéolo. Análise intergrupo mostrou que não houve diferença estatisticamente significante aos 3 dias (p>0,05) para todos os parâmetros. Aos 7 dias, a IFC influenciou negativamente (p?0,05) o preenchimento ósseo mostrando diferença estatisticamente significante para os parâmetros tecido não mineralizado e defeito remanescente (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, para controle e teste, respectivamente). No entanto, não houve diferença estatisticamente significante (p>0,05) aos 10 e 14 dias. Conclui-se que a IFC pode afetar o reparo ósseo alveolar inicial, o que pode ser crítico para a quantidade e qualidade da nova formação óssea em fumantes.

Cola beverage consumption delays alveolar bone healing: a histometric study in rats

Epidemiological studies have suggested that cola beverage consumption may affect bone metabolism and increase bone fracture risk. Experimental evidence linking cola beverage consumption to deleterious effects on bone is lacking. Herein, we investigated whether cola beverage consumption from weaning to early puberty delays the rate of reparative bone formation inside the socket of an extracted tooth in rats. Twenty male Wistar rats received cola beverage (cola group) or tap water (control group) ad libitum from the age of 23 days until tooth extraction at 42 days and euthanasia 2 and 3 weeks later. The neoformed bone volume inside the alveolar socket was estimated in semi-serial longitudinal sections using a quantitative differential point-counting method. Histological examination suggested a decrease in the osteogenic process within the tooth sockets of rats from both cola groups, which had thinner and sparser new bone trabeculae. Histometric data confirmed that alveolar bone healing was significantly delayed in cola-fed rats at three weeks after tooth extraction (ANOVA, p = 0.0006, followed by Tukey's test, p < 0.01). Although the results of studies in rats cannot be extrapolated directly to human clinical dentistry, the present study provides evidence that cola beverage consumption negatively affect maxillary bone formation.

Evaluation of subcutaneous and alveolar implantation surgical sites in the study of the biological properties of root-end filling endodontic materials

OBJECTIVE: The aim of this study was to compare two methodologies used in the evaluation of tissue response to root-end filling materials in rats. MATERIAL AND METHODS: Forty rats were divided into 4 groups: in Groups I and II (control groups), empty polyethylene tubes were implanted in the extraction site and in the subcutaneous tissue, respectively; in Groups III and IV, polyethylene tubes filled with ProRoot MTA were implanted in the extraction site and in the subcutaneous tissue, respectively. The animals were killed 7 and 30 days after tube implantation, and the hemi-maxillas and the capsular subcutaneous tissue, both with the tubes, were removed. Specimens were processed and evaluated histomorphologicaly under light microscopy. The scores obtained were analyzed statistically by the Kruskal-Wallis test (p<0.05). RESULTS: There were no statistically significant differences between the implantation methods (p=0.78033, p=0.72039). It was observed that the 30-day groups presented a more mature healing process due to smaller number of inflammatory cells. CONCLUSIONS: The present study showed no differences in tissue responses as far as the implantation site and the studied period were concerned. Alveolar socket implantation methodology represents an interesting method in the study of the biological properties of root-end filling endodontic materials due to the opportunity to evaluate bone tissue response.

Bone quality associated with daily intake of coffee: a biochemical, radiographic and histometric study

Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-µm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg percent) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 percent) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.

A cafeína induz perda de cálcio e influencia no desenvolvimento ósseo normal. Este estudo investiga os efeitos do café sobre o metabolismo ósseo em ratos através de avaliações bioquímicas do cálcio, densitometria e histometria óssea. Ratos machos, nascidos de fêmeas tratadas diariamente com café, e com ingestão de café desde o nascimento, foram anestesiados, submetidos à extração do incisivo superior direito e sacrificados 7, 21 e 42 dias após a cirurgia. Amostras de sangue e urina foram colhidas, suas maxilas radiografadas e processadas para se obter cortes semi seriados (5 µm) e corados pela hematoxilina-eosina. Através de um programa de análise de imagens, o volume e a qualidade do osso foram avaliados. Os resultados demonstraram maior quantidade de cálcio no sangue (9,40 ± 1,73 versus 9,80 ± 2,05 mg por cento) e urina (1,00 ± 0,50 versus 1,25 ± 0,70 mg/24 h) e menor no osso (90,0 ± 1,94 versus 86,0 ± 2,12 mg/mg osso), densidade mineral óssea menor (1,05 ± 0,11 versus 0,65 ± 0,15 mmAL), e menor quantidade de osso (76,19 ± 1,6 versus 53,41 ± 2,1 por cento) estatisticamente significante (ANOVA p≤0,01) nos animais tratados com café sacrificados após 42 dias. Conclui-se que a ingestão de café/cafeína causou sérios efeitos adversos no metabolismo de cálcio em ratos, incluindo aumento dos níveis de cálcio na urina e no plasma, diminuição da densidade mineral óssea e menor volume de osso atrasando o processo de reparo ósseo.

Influence of local tetracycline on the microbiota of alveolar osteitis in rats

The aim of the present study was to evaluate the effects of local tetracycline on the occurrence of alveolar osteitis in rats, and on the microbiota associated to this infection. Forty Wistar rats were randomly assigned to 4 groups (n=10): I - the rats had the maxillary right incisor extracted and the alveolar wound did not receive any treatment; II - adrenaline and Ringer-PRAS were introduced into the alveolar wound; III - the alveolar wound was irrigated with sterile saline; and IV - the alveolar wound was irrigated with an aqueous solution of tetracycline. Microbial samples from the alveolar wounds were collected 2 days after surgery and inoculated on blood agar (with and without 8 µg/mL of tetracycline) and other selective media, and were incubated in either aerobiosis or anaerobiosis at 37ºC, for 2 to 14 days. It was verified that tetracycline reduced the occurrence of alveolar osteitis in the rats and caused significant changes in the microbiota of the surgical sites, decreasing the number of anaerobes and increasing the participation of tetracycline-resistant and multi-resistant microorganisms.

O objetivo do presente estudo foi avaliar os efeitos do uso tópico de tetraciclina sobre a ocorrência de alveolite em ratos e sobre a microbiota a ela associada. Quarenta ratos foram divididos, ao acaso, em 4 grupos (n=10): grupo I, realizou-se somente a extração do incisivo superior direito e a ferida alveolar não recebeu nenhum tratamento; grupo II, além da extração dental, soluções de adrenalina e Ringer-PRAS foram introduzidas no interior do alvéolo; grupo III, a ferida alveolar foi irrigada com solução salina estéril; grupo IV, a ferida alveolar foi irrigada com solução aquosa de cloridrato de tetraciclina a 10 por cento. As amostras dos alvéolos para processamento microbiológico foram coletadas dois dias após a realização das cirurgias e foram inoculadas em ágar sangue com ou sem 8 µg/mL de tetraciclina e em outros meios de cultura seletivos, incubadas em aerobiose ou anaerobiose, a 37ºC, de 2 a 14 dias. Verificou-se que a tetraciclina reduziu a ocorrência de alveolite e provocou uma modificação significativa na microbiota do sítio cirúrgico, levando a uma redução nas proporções ocupadas pelos microrganismos anaeróbios e uma elevação da participação de microrganismos resistentes à tetraciclina e outros antimicrobianos.

Densitometric analysis of the autogenous demineralized dentin matrix on the dental socket wound healing process in humans

The aim of this study was to evaluate the effects of the autogenous demineralized dentin matrix (ADDM) on the third molar socket wound healing process in humans, using the guided bone regeneration technique and a polytetrafluoroethylene barrier (PTFE). Twenty-seven dental sockets were divided into three groups: dental socket (Control), dental socket with PTFE barrier (PTFE), and dental socket with ADDM slices associated to PTFE barrier (ADDM + PTFE). The dental sockets were submitted to radiographic bone densitometry analysis and statistical analysis on the 15th, 30th, 60th and 90th days using analysis of variance (ANOVA) and Tukey's test (p £ 0.05). The radiographic analysis of the ADDM + PTFE group showed greater homogeneity of bone radiopacity than the Control group and the PTFE group, during all the observation times. The dentin matrix gradually disappeared from the dental socket during the course of the repair process, suggesting its resorption during the bone remodeling process. It was concluded that the radiographic bone density of the dental sockets treated with ADDM was similar to that of the surrounding normal bone on the 90th day. The ADDM was biocompatible with the bone tissue of the surgical wounds of human dental sockets. The radiographic analysis revealed that the repair process was discreetly faster in the ADDM + PTFE group than in the Control and PTFE groups, although the difference was not statistically significant. In addition, the radiographic image of the ADDM + PTFE group suggested that its bone architecture was better than that of the Control and PFTE groups.

O objetivo desta pesquisa foi avaliar a reparação óssea em alvéolos dentários após exodontia dos terceiros molares inferiores em humanos, com implantação de matriz dentinária desmineralizada autógena (MDDA) na cavidade e cobertura desta com barreira de politetrafluoretileno (PTFE). Foram selecionados 27 dentes, os quais foram divididos em três grupos: alvéolo dentário (Controle), alvéolo dentário com barreira de PTFE (PTFE) e alvéolo dentário com fatias de MDDA associada à barreira de PTFE (MDDA + PTFE). O alvéolo dentário foi submetido à análise de densitometria radiográfica e à análise estatística no 15°, 30°, 60° e 90° dias, utilizando-se a análise de variância (ANOVA) e teste de Tukey (p < 0,05). A análise radiográfica do grupo MDDA + PTFE mostrou maior homogeneidade na radiopacidade do trabeculado ósseo do que no grupo controle e grupo PTFE, durante todos os períodos de observação. A matriz dentinária foi desaparecendo do alvéolo dentário durante a evolução do processo de reparo, sugerindo sua reabsorção durante o processo de remodelação óssea. Concluiu-se que a densidade óssea radiográfica do alvéolo dentário tratado com MDDA foi similar à do osso normal circunjacente no 90° dia. A MDDA foi biocompatível com o tecido ósseo, quando implantada nos alvéolos dentários cruentos de humanos. Na análise radiográfica, pode-se verificar que o processo de reparo foi discretamente mais rápido no grupo MDDA + PTFE do que no grupo Controle e no grupo PTFE, porém não houve diferença estatística significante. Além disso, a imagem radiográfica sugeriu que a arquitetura óssea do grupo MDDA + PTFE foi melhor do que a arquitetura óssea do grupo controle e grupo PTFE.

Effects of Tissucol™ and epsilon aminocaproic acid in the healing process following dental extraction in dehydrated rats

Foi estudada histologicamente a reparação do alvéolo dental de ratos desidratados, após o implante de adesivo fibrínico (TISSUCOL®) associado à irrigação prévia da ferida com solução a 5% de ácido épsilon-aminocapróico. Foram empregados 72 ratos, divididos em três grupos, que receberam diferentes tratamentos após o procedimento cirúrgico. No Grupo I, após a extração do incisivo superior direito, a mucosa gengival foi suturada. Nos Grupos II e III foi provocada a desidratação crônica pela privação de ingestão de líquidos durante 09 dias (3 dias no pré-operatório e 6 dias no pós-operatório), sendo que, no Grupo II, após a extração dental, a mucosa gengival foi suturada de forma semelhante à do Grupo I; no Grupo III, logo após a exodontia, o alvéolo foi irrigado com a solução de ácido épsilon-aminocapróico a 5%, seguida de implante de adesivo fibrínico (TISSUCOL®) e foi feita sutura da mucosa de forma semelhante à dos demais grupos. Decorridos 3, 7, 15 e 21 dias após o ato operatório, os animais foram sacrificados em número de 6 para cada grupo. A seguir, as peças contendo o alvéolo dental foram removidas e fixadas em formalina a 10% e descalcificadas em solução de ácido fórmico e citrato de sódio em partes iguais. Após processamento laboratorial de rotina, foram incluídas em parafina para microtomia. Foram obtidos cortes semi-seriados com 6 micrômetros de espessura, seguidos de coloração em hematoxilina e eosina para estudo microscópico. Os resultados obtidos mostram que a hidroprivação no pré e pós-operatório ocasiona profundo retardo no processo de reparo em feridas de extração dental. O emprego de adesivo fibrínico (TISSUCOL®) melhora o quadro fibrinolítico provocado pela desidratação.

Histologic study of use of microfibrillar collagen hemostat in rat dental sockets

The aim of this paper was to evaluate if the placement of microfibrillar collagen hemostat (MCH) into a dental socket interfered with healing. General anesthesia was administered to 30 adult male Albinus Wistar rats and the maxillary right central incisor was extracted. In the control group after each tooth was extracted, the socket was sutured. In the MCH group after each tooth was extracted, MCH was placed into the socket before suturing. Postoperatively, 5 animals were sacrificed from each group at 7, 21 and 28 days. The right maxilla was removed from each animal and histologic slides were stained with Masson's trichromic and hematoxylin and eosin. Quantitative and qualitative analyses were done. The percentage of bone area in the dental socket was quantified using the Image Lab 98 image analysis system. The bone area formation for the control and MCH groups was: 8.1 percent and 3.3 percent at 7 days, 34.4 percent and 33 percent at 21 days and 41 percent and 41.3 percent at 28 days, respectively. We concluded that MCH interferes with the beginning of dental socket healing but does not interfere with the final healing of the dental socket