Biodentine and MTA modulate immunoinflammatory response favoring bone formation in sealing of furcation perforations in rat molars.

OBJECTIVES: Evaluate the tissue reaction of periodontium subjacent to furcation perforations in rat molars sealed with Biodentine or mineral trioxide aggregate (MTA). MATERIALS AND METHODS: The pulp chamber floor of right upper first molars of 60 rats was perforated and filled with Biodentine, MTA, or cotton pellet (sham); the left first molars were used as control. After 7, 15, 30, and 60 days, maxillary fragments were processed for paraffin-embedding. The periodontal space (PS), volume density of inflammatory cells (VvIC) and fibroblasts (VvFb), number of osteoclasts, and collagen content were obtained. Interleukin-6 (IL-6) and osterix (osteoblast marker) were detected by immunohistochemistry. The data were submitted to ANOVA and Tukey's test (p ≤ 0.05). RESULTS: At 7 days, high values in VvIC, IL-6-immunolabeled cells, and osteoclasts were accompanied by reduced collagen content in enlarged PS of experimental groups. At all periods, VvIC, number of osteoclasts and IL-6, and PS were higher in sham than in Biodentine and MTA (p < 0.0001). From 7 to 60 days, significant reduction in VvIC, IL-6 immunoexpression, and osteoclasts was accompanied by significant increase in VvFb, osteoblasts, and collagen in Biodentine and MTA groups. At 60 days, significant differences in VvIC, PS, IL-6, osteoclasts, and osteoblasts were not found between Biodentine and MTA. Significant differences in the osteoclast number were not observed among Biodentine, MTA, and control groups while osteoblasts number was higher in Biodentine and MTA groups. CONCLUSIONS: Despite the initial inflammatory reaction and bone resorption, the sealing of furcation perforations with Biodentine and MTA favors the repair of periodontal tissues. CLINICAL RELEVANCE: Biodentine and MTA exhibit potential as repair material in the treatment of furcation perforations.

Reduced interleukin-6 immunoexpression and birefringent collagen formation indicate that MTA Plus and MTA Fillapex are biocompatible.

Considering that endodontic sealers release some components which may promote delay in the repair process, our purpose was to evaluate the tissue reaction promoted by MTA Plus and MTA Fillapex in comparison with AH Plus (standard control) and Endofill, which has a long clinical track record. One hundred rats were distributed into five groups: MTA Plus (Avalon Biom Inc., Bradenton, FL, USA), MTA Fillapex (Angelus, Londrina, PR, Brazil), AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany), Endofill (Dentsply, Petrópolis, RJ, Brazil) and CG (control group, empty polyethylene tubes). The polyethylene tubes filled with sealers or empty (CG) were implanted into subcutaneous. After 7, 15, 30 and 60 days, the tubes surrounded by capsules were paraffin-embedded. In HE-stained sections, the volume density of inflammatory cells (VvIC) was estimated in the capsules. The number of interleukin-6-immunolabelled cells (IL-6), a pro-inflammatory cytokine, was also computed in the capsules. The birefringent collagen content was quantified in picrosirius-stained sections. Data were analysed by ANOVA and Tukey tests (p ≤ 0.05). At 7 days, the capsules showed moderate inflammatory reaction. In all groups, VvIC and IL-6-immunostained cells reduced significantly from 7 to 60 days. At 60 days, IL-6 immunoexpression was reduced significantly in MTA Plus and MTA Fillapex in comparison with AH Plus; no difference was found in the VvIC among MTA Plus, MTA Fillapex, AH Plus and CG whereas Endofill exhibited the highest VvIC. The reduction in VvIC was parallel to an increase in the collagen in all the groups, except Endofill. MTA Plus, MTA Fillapex and AH Plus induce a response that culminates in the regression of inflammation and formation of a fibrous capsule over time. The lower IL-6 immunoexpression in the capsules of MTA Plus and MTA Fillapex than AH Plus suggests that the immune response is suppressed more rapidly in the MTA-based sealers.

Cleaning capacity of hybrid instrumentation technique using reamer with alternating cutting edges system files: Histological analysis.

AIM: The aim of the following study is to evaluate the cleaning capacity of a hybrid instrumentation technique using Reamer with Alternating Cutting Edges (RaCe) system files in the apical third of mesial roots of mandibular molars. MATERIALS AND METHODS: Twenty teeth were selected and separated into two groups (n = 20) according to instrumentation technique as follows: BioRaCe - chemomechanical preparation with K-type files #10 and #15; and files BioRaCe BR0, BR1, BR2, BR3, and BR4; HybTec - hybrid instrumentation technique with K-type files #10 and #15 in the working length, #20 at 2 mm, #25 at 3 mm, cervical preparation with Largo burs #1 and #2; apical preparation with K-type files #15, #20, and #25 and RaCe files #25.04 and #30.04. The root canals were irrigated with 1 ml of 2.5% sodium hypochlorite at each change of instrument. The specimens were histologically processed and photographed under light optical microscope. The images were inserted onto an integration grid to count the amount of debris present in the root canal. RESULTS: BioRaCe presented the highest percentage of debris in the apical third, however, with no statistically significant difference for HybTec (P > 0.05). CONCLUSIONS: The hybrid technique presented similar cleaning capacity as the technique recommended by the manufacturer.