RESUMO
AIM: To evaluate the relationship between systemic administration of probiotics and inflammation/resorption processes associated with apical periodontitis (AP) in a rat model. METHODOLOGY: Twenty-four male Wistar rats were used. AP was induced in the mandibular left/right first molars. The animals were arranged into three groups: Control, Lactobacillus rhamnosus and L. acidophilus. Probiotics were orally administered via gavage (109 colony-forming units (CFU) diluted in 5 mL of water) for 30 days during the development of AP. On the 30th day, blood was collected to analyse the calcium, phosphorus and alkaline phosphatase concentrations in plasma. Then, the animals were euthanized and the jaws removed for micro-computed tomography and immune-histopathological analysis for receptor activator of NF-κB ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP). After the Shapiro-Wilk test of normality, the Kruskal-Wallis followed by Dunn's test was performed for nonparametric data, and analysis of variance followed by the Tukey test was performed for parametric data (P < 0.05). RESULTS: There was no significant difference in the calcium and phosphorus levels in plasma amongst the groups (P > 0.05). The level of alkaline phosphatase was significantly higher in the groups that consumed probiotics (P < 0.05). A significantly lower volume of bone resorption was observed in groups that consumed probiotics (P < 0.05). The inflammatory infiltrates and the immunolabelling for RANKL and TRAP were significantly lower in probiotic groups when compared to the control (P < 0.05). Also, the OPG was significantly more immunolabelled in the L. acidophilus group than in the L. rhamnosus and control groups (P < 0.05). CONCLUSION: Probiotic supplementation through gavage (L. rhamnosus and L. acidophilus) had a significant effect on the reduction of inflammation and bone resorption in apical periodontitis development in rats.
Assuntos
Reabsorção Óssea , Periodontite Periapical , Probióticos , Animais , Inflamação , Masculino , Osteoprotegerina , Ligante RANK , Ratos , Ratos Wistar , Microtomografia por Raio-XRESUMO
AIM: To analyse the influence of H2 O2 on pulp repair through osteocalcin and osteopontin immunolabelling and in cellular defence by using the antireactive oxygen species (ROS) antibody. METHODOLOGY: The maxillary molars of 50 rats were treated with 35% H2 O2 (Ble groups) or placebo gel (control groups). At 0 h and 2, 7, 15 and 30 days (n = 10 hemimaxillae), the rats were killed and pulp tissue was evaluated using inflammation and immunolabelling scores (osteocalcin/osteopontin); ROS-positive cells were counted. Paired t-test and Wilcoxon signed-rank test were used (P < 0.05). RESULTS: The Ble group had necrosis in the coronal pulp at 0 h and in the occlusal third of the coronal pulp at 2 days; at 7, 15 and 30 days, no inflammation was noted similar to the controls (P > 0.05). Osteocalcin was absent in the Ble at 0 h, moderate at 2 days and increased thereafter, differing from the controls at all two periods (P < 0.05). Osteopontin was higher principally at 7 and 15 days in Ble groups, but differing with control groups from 2 days after bleaching (P < 0.05). The Ble group had more ROS-positive cells in the pulp at 7 and 15 days (P < 0.05). Tertiary dentine was observed at 7 days, increasing thereafter (P < 0.05). CONCLUSIONS: Post-bleaching pulp repair was associated with increased osteocalcin over time. Osteopontin also participated in this process, and anti-ROS was involved in cellular defence against H2 O2 .
Assuntos
Osteopontina , Clareadores Dentários , Animais , Polpa Dentária , Peróxido de Hidrogênio , Osteocalcina , Ratos , Ratos WistarRESUMO
AIM: To evaluate the inflammatory response and ability to induce mineral deposition through histological and immunohistochemical analysis for osteocalcin (OCN), osteopontin (OPN) and bone sialoprotein (BSP) of a new calcium silicate-based cement, Bio-C Pulpo (Angelus), compared to white mineral trioxide aggregate (White MTA-Ang) (Angelus). METHODOLOGY: Polyethylene tubes containing Bio-C Pulpo and White MTA-Ang as well as empty tubes were implanted into the dorsal connective tissue of 30 Wistar rats, which were arranged in five groups according to the period of analysis: 7, 15, 30, 60 and 90 days. After each experimental period, the tubes with surrounding tissue were removed and histologically processed to be analysed using haematoxylin-eosin and immunohistochemistry for the detection of OCN, OPN and BSP. The data were statistically analysed (Friedman's test) at a 5% significance level. RESULTS: The inflammatory response observed with Bio-C Pulpo and White MTA-Ang was greater after 7 and 15 days and decreased from 30 days onwards. No significant difference was found between the control, Bio-C Pulpo and White MTA-Ang at the different periods of analysis (P > 0.05). The immunolabelling for OCN, OPN and BSP was more intense for Bio-C Pulpo and White MTA-Ang after 60 and 90 days, but there was no difference between Bio-C Pulpo and White MTA-Ang at the different periods of analysis (P > 0.05). CONCLUSION: Bio-C Pulpo is biocompatible and induces immunolabelling of osteogenic markers such as OCN, OPN and BSP similar to White MTA-Ang.
Assuntos
Cálcio , Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Animais , Materiais Biocompatíveis , Compostos de Cálcio , Cimentos Dentários , Combinação de Medicamentos , Óxidos , Ratos , Ratos Wistar , SilicatosRESUMO
AIM: To investigate the effect of chronic alcohol consumption on apical periodontitis in rats. METHODOLOGY: Thirty-two male Wistar rats were arranged into four groups: Control (C): without apical periodontitis and nonalcoholic diet; (AL): without apical periodontitis and alcoholic diet; (AP): with apical periodontitis and nonalcoholic diet; and (AP + AL): with apical periodontitis and alcoholic diet. The alcoholic solution at 20% was given to the AL and AP + AL groups as the sole source of hydration throughout the experiment. AP was induced in the mandibular left first molars at the end of the 4th week. Weight changes and the amount of solid and liquid foods were recorded for 8 weeks. At the end, the animals were euthanized and the jaws removed followed by histological processing for histopathological and RANKL, OPG, TRAP and HIF-1α analyses. The Mann-Whitney test was used for nonparametric data, and anova followed by the Tukey test was performed for parametric data, with P < 0.05. RESULTS: Animals that received the alcoholic diet had a lower weight gain than the other groups (P < 0.05). Control and AL groups did not have an inflammatory response in the periapical tissues. The median score of inflammatory infiltrate was significantly higher in the AP + AL group (2.5) compared to the AP group (1.5; P < 0.05). In the same comparison, AP + AL was associated with score 3 for RANKL and HIF-1α versus score 2 for AP group (P < 0.05). Moreover, the values for TRAP were 3.88 ± 0.70 cells mm-1 for the AP + AL group and 2.43 ± 0.94 cells mm-1 for the AP group (P < 0.05). CONCLUSION: In rats, an alcoholic diet had a significant effect on the severity of apical periodontitis, exacerbating the inflammatory response and osteoclastogenesis.
Assuntos
Etanol/administração & dosagem , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Periodontite Periapical/patologia , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato/metabolismo , Aumento de PesoRESUMO
AIM: To investigate the relationship between diabetes mellitus and local/systemic effects of both grey and white mineral trioxide aggregate (MTA) Angelus on bone marker expression. METHODOLOGY: Wistar rats were divided into two groups: healthy and diabetic (Alloxan induced), which were further divided into three subgroups (control, GMTA Angelus and WMTA Angelus). Polyethylene tubes filled with MTA materials or empty tubes were implanted in dorsal connective tissue. On days 7 and 30, blood samples were collected for calcium, phosphorus and ALP measurement. The animals were euthanized; implanted tubes were removed and processed for immunohistochemical analysis of osteocalcin (OCN) and osteopontin (OPN). Kruskal-Wallis followed by Dunn's multiple comparison test was performed for nonparametric data, and anova followed by Tukey's test for parametric data. RESULTS: No difference in systemic serum calcium levels between both groups was observed. On day 7, serum phosphorus levels within the WMTA healthy group were higher than that of the diabetic group. On day 30, healthy rats exhibited lower phosphorus levels than diabetic ones. At both time points, the diabetic group was associated with more ALP activity than the healthy group. Immunohistochemical analyses of the healthy group revealed OCN- and OPN-positive cells in the presence of both MTA materials. However, under diabetic conditions, both OCN and OPN were absent. CONCLUSION: Both MTA materials were associated with an increase in serum calcium, phosphorus and ALP, suggesting a potential systemic effect, along with triggered differentiation of OCN- and OPN-positive cells. Moreover, in diabetic conditions, an inhibitory effect on MTA-induced differentiation of OCN- and OPN-positive cells was detected.
Assuntos
Compostos de Alumínio/análise , Compostos de Cálcio/análise , Diabetes Mellitus Experimental/metabolismo , Óxidos/análise , Silicatos/análise , Animais , Diabetes Mellitus Experimental/sangue , Combinação de Medicamentos , Imuno-Histoquímica , Osteocalcina/análise , Osteopontina/análise , Ratos , Ratos WistarRESUMO
AIM: To evaluate lymphocyte-like cell activation (CD5-positive cells) and the expression of interleukin (IL)-6 and IL-17 in the pulp after tooth bleaching with two concentrations of hydrogen peroxide (H2 O2 ). METHODOLOGY: The right and left maxillary molars from 40 rats were treated randomly with bleaching gel with 20% H2 O2 (BLUE group, 1 application of 50 min), 35% H2 O2 (MAXX group, three applications of 15 min), or placebo gel (control). After 2 and 30 days, the rats were killed (n = 10), and the jaws were processed for histological and immunohistochemistry analysis of the pulp tissue. The scores of inflammation and immunolabelling (IL-6/IL-17) were submitted to Mann-Whitney and Kruskal-Wallis followed Dunn tests, respectively; anova tests were used for comparisons of number of CD5-positive cells and pulp chamber area values (P < 0.05). RESULTS: At 2 days, 60% of specimens of the BLUE group were associated with moderate inflammation in pulp horns, and in the MAXX group with necrosis (P < 0.05). At 30 days, the pulp was organized, and tertiary dentine was formed. The MAXX group had superior immunolabelling of IL-17 at 2 days differing significantly from other groups (P < 0.05). At 2 days, 90% of the specimens of the BLUE group had moderate immunolabelling of IL-6, and 50% of the MAXX group had severe immunolabelling, both significantly different from the control (P < 0.05). There was no significant difference between the groups at 30 days (P > 0.05). CD5-positive cells were present at 2 and 30 days, particularly in the bleached groups (P < 0.05), without significant difference between time periods (P > 0.05). CONCLUSIONS: IL-6 and IL-17 participated in inflammation in the pulp tissue of rats after tooth bleaching, particularly at 2 days. The immunolabelling was greater with increasing H2 O2 concentration. This process was accompanied by the prolonged activation of CD5-positive cells.
Assuntos
Antígenos CD5/metabolismo , Polpa Dentária/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Clareadores Dentários/farmacologia , Animais , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Ratos , Ratos WistarRESUMO
AIM: To investigate whether hypertension affects mineralization associated with white and grey mineral trioxide aggregate (MTA Angelus® ) implanted subcutaneously into rats by assaying osteoblastic biomarkers. METHODOLOGY: Polyethylene tubes containing grey MTA Angelus® , white MTA Angelus® , intermediate restorative material (IRM; positive control) or an empty tube (negative control) were implanted into the dorsal connective tissue of spontaneous hypertensive (n = 12) and Wistar (normotensive; n = 10) rats. Half of the rats in each group were killed after 7 days, and the remaining after 30 days. Tubes with surrounding tissue were removed, and immunostaining was performed to detect RUNX-2, OPN and OCN proteins. The normality of data was analysed using the Shapiro-Wilk test. Comparison of two independent groups was performed using the Mann-Whitney U-test, to detect a significant difference. A post hoc test accounting for multiple comparisons was performed following Tukey's test (P < 0.05). RESULTS: Under hypertensive conditions after 30 days, both MTA materials were associated with immunolabelling for RUNX-2 from low to moderate, which was less than that observed at normal blood pressure and the 7-day groups (P < 0.05). The expression of OPN and OCN proteins under both MTA conditions was considered low after both 7 and 30 days for the hypertensive condition, and was less than that in animals with normal blood pressure after 30 days (P < 0.05). No immunostaining for any biomarkers in the control and IRM groups was observed (P < 0.05). CONCLUSION: Hypertension decreased the immunostaining of RUNX-2, OPN and OCN biomarkers in response to MTA. Thus, hypertension can jeopardize the mineralization ability of MTA and may have a negative impact on endodontic treatment outcomes.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Hipertensão/metabolismo , Proteínas Nucleares/metabolismo , Osteocalcina/metabolismo , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Animais , Materiais Biocompatíveis/farmacologia , Biomarcadores/metabolismo , Tecido Conjuntivo/efeitos dos fármacos , Combinação de Medicamentos , Ratos , Ratos WistarRESUMO
AIM: To evaluate the influence of tooth bleaching on immunoregulatory cytokines production (IL-6, Tumour necrosis factor (TNF)-α and IL-17) in the pulp tissue of normoglycaemic and diabetic rats. METHODOLOGY: Twenty-eight rats were divided into normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with a single dose of alloxan diluted in citrate buffer via intramuscular injection. After DM confirmation, all rats were sedated and tooth bleaching was performed using 35% hydrogen peroxide on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 and 30 days, rats were euthanized and hemimaxillae processed for analysis by haematoxylin and eosin and immunohistochemistry. Results within and between animals were submitted to Wilcoxon signed-rank and Mann-Whitney tests (P < 0.05). RESULTS: At 2 days, the NBle group had mild, and the DBle had severe inflammatory infiltration in the pulpal tissue (P < 0.05). TNF-α and IL-6 cytokines were associated with increased immunolabelling in the bleached groups compared to nonbleached (P < 0.05). However, IL-17 had increased immunolabelling in the NBle compared to the N and DBle group (P < 0.05). At 30 days, reactionary dentine was observed in the coronal pulp of all bleached teeth and no inflammation was present (P > 0.05). TNF-α cytokines had increased immunolabelling in the DBle group compared to the D group (P < 0.05). However, for IL-6 and IL-17, no difference was observed in this period (P > 0.05). CONCLUSIONS: Tooth bleaching increased IL-6 and TNF-α in the pulp tissue regardless of diabetes mellitus; however, diabetic rats had higher TNF-α levels for longer periods. Tooth bleaching influenced the increase in IL-17 in the early periods in normoglycaemic rats.
Assuntos
Polpa Dentária/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Peróxido de Hidrogênio/farmacologia , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Clareadores Dentários/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Polpa Dentária/metabolismo , Masculino , Ratos , Ratos Wistar , Clareamento Dental/métodosRESUMO
AIM: To evaluate pulpal tissue response after dental bleaching in normal and alloxan-induced diabetic rats. METHODOLOGY: Twenty-eight rats were divided into two groups of normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with alloxan. After DM confirmation, all rats were anaesthetized and dental bleaching was performed with 35% hydrogen peroxide (H2 O2 ) on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 or 30 days, the animals were euthanized and the hemimaxillae were removed, processed for histopathological analysis and stained with haematoxylin-eosin (HE), Masson's trichrome (MT) and picrosirius red (PSR). Results obtained within animals (normoglycaemic or diabetic rats) were submitted to Wilcoxon or paired t-tests, and between animal (normoglycaemic and diabetic rats), to Mann-Whitney test or t-tests. RESULTS: At 2 days, the NBle group had a mild inflammatory infiltration in the pulpal tissue, whilst the DBle had severe inflammation or necrosis (P < 0.05). At 30 days, no inflammation was present. However, a significant difference in pulp chamber area reduction by reactionary dentine deposition was found between the NBle and DBle groups (P < 0.05). At 2 days, fewer immature collagen fibres and more mature collagen fibres were noted in the NBle, D and DBle groups; this was significantly different when compared to the N group (P < 0.05). At 30 days, significantly fewer immature collagen fibres and more mature collagen fibres were noted in NBle compared with DBle group (P < 0.05). CONCLUSIONS: The inflammatory tissue response in rats' teeth after dental bleaching was greater in diabetic rats. Additionally, the increase in reactionary dentine deposition and mature collagen fibres observed in diabetic rats needs further evaluation to confirm the present results.
Assuntos
Cavidade Pulpar/patologia , Diabetes Mellitus Experimental/fisiopatologia , Peróxido de Hidrogênio/efeitos adversos , Pulpite/induzido quimicamente , Clareadores Dentários/efeitos adversos , Animais , Masculino , Necrose/induzido quimicamente , Ratos WistarRESUMO
AIM: To analyse the local regulatory mechanisms of osteoclastogenesis and angiogenesis during the progression of periapical lesions in female rats with oestrogen deficiency and treatment with raloxifene (RLX). METHODOLOGY: Female Wistar rats were distributed into groups: SHAM-veh, subjected to sham surgery and treated with a vehicle; OVX-veh, subjected to ovary removal and treated with a vehicle; and OVX-RLX, subjected to ovary removal and treated with RLX. Vehicle or RLX was administered orally for 90 days. During treatment, the dental pulp of mandibular first molars was exposed to the oral environment for induction of periapical lesions, which were analysed after 7 and 30 days. After the experimental periods, blood samples were collected for measurement of oestradiol, calcium, phosphorus and alkaline phosphatase. The rats were euthanized and the mandibles removed and processed for immunohistochemical detection of receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG), hypoxia-inducible factor-1 alpha (HIF-1α) and bone-specific alkaline phosphatase (BALP). Data were compared using Kruskal-Wallis followed by Dunn test (nonparametric values) and anova followed by the Tukey's test (parametric values). RESULTS: The plasma concentration of oestradiol showed hypo-oestrogenism in the rats subjected to ovary removal. On day 7, alkaline phosphatase activity, calcium and phosphorus were higher in the OVX-RLX group than in the OVX-veh group (P < 0.001), but immunolabelling for RANKL and HIF-1α was lower in OVX-RLX group (P < 0.001). On day 30, the OVX-veh group had higher immunolabelling for RANKL than the OVX-RLX group (P < 0.05). There were no significant differences in the immunoreactivity of OPG and BALP between any groups at either time-point (P > 0.05). CONCLUSION: RLX therapy reversed the increased levels of the local regulators of both osteoclastogenesis and angiogenesis induced by oestrogen deficiency.