Biological, physical and chemical properties of a bioceramic intracanal medication

Author(s)

Camila Soares Lopes

• Document type: Doctoral Thesis
• Press: Araraquara. 2022-06-29.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araraquara
• Defense date: 2022-05-20
• Advisor: Paulo Sérgio Cerri; Juliane Maria Guerreiro Tanomaru

Abstract

The aim of the study was to evaluate the biocompatibility and bioactive potential of a bioceramic intracanal medication, Bio-C Temp (BIO; Angelus, Londrina, Brazil), in comparison to a calcium hydroxide-based medication, Calen (CAL; SS White, Rio de Janeiro, Brazil) implanted into the subcutaneous tissues of 60 rats for 7, 15, 30 and 60 days. Analyses of physicochemical properties, including radiopacity, pH, solubility, flowability, volumetric change (%) and filling capacity were conducted with BIO and CAL medications. Publication 1: The thickness of the capsules, the number of inflammatory cells (IC), immunopositive cells for interleukin-6 (IL-6) and IL-10, and collagen content were measured. Serum glutamic-oxalacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) levels were evaluated at 7 and 60 days. The data were submitted ANOVA and Tukey’s test (p ≤ 0.05). Significant differences in the serum GOT and GPT levels were not detected (p > 0.05). The capsules around the BIO and CAL specimens were thicker at 30 days than at 60 days. In all periods, the number of IC and IL-6-immunopositive cells was significantly lower in BIO than in CAL specimens. In BIO and CAL specimens, the number of IL-10-immunopositive cells increased significantly over time. At 60 days, the capsules around the BIO contained greater collagen content than in CAL specimens (p < 0.0001). Tissue damage initially caused by BIO was suppressed more quickly compared to that caused by CAL, favoring connective tissue repair. Publication 2: In this study, the concentration of calcium (Ca+2), phosphorus (P-) and alkaline phosphatase (ALP) in the serum, the immunoexpression of osteocalcin (OCN) and osteopontin (OPN), the number of fibroblasts and the deposition of amorphous calcite were evaluated. Data were submitted to ANOVA and post-hoc Tukey test (p≤0.05). At 7 and 15 days, serum Ca+2 levels were higher in the CAL than in BIO samples while the P- concentration was highest in BIO and CAL in comparison to control group (CG; empty tubes) at 7 days. The ALP level was high in BIO and CAL up to 30 days, decreasing significantly at 60 days. In BIO and CAL, a significant increase in the number of fibroblasts, in the immunoexpression of IL-10, OCN and OPN was detected over time. In constrast, OCN- and OPN-immunolabelled cells were not seen in the CG specimens. BIO and CAL specimens showed von Kossa-positive structures and birefringent deposits, while in the CG, these structures were not observed. BIO, as well as CAL, caused an increase in the serum ALP levels, an essential enzyme in biomineralization, and induced subcutaneous tissue cells to synthesize OCN and OPN, in addition to calcite deposition, indicating that BIO has bioactive potential. Publication 3: In the present study, pH, radiopacity, flowability, solubility (after 7 and 14 days immersion in distilled water and PBS), volumetric change and filling capacity (by micro-CT) were evaluated. ANOVA and Tukey’s test and T test (p≤0.05) were applied. CAL showed higher pH, flow, volumetric change and solubility after 14 days of immersion in distilled water, and at 7 and 14 days in PBS. BIO showed greater radiopacity and filling capacity (p<0.05). Despite the bioceramic medication presenting less volumetric loss and satisfactory filling capacity, avoiding voids and failures, Bio-C Temp showed lower alkalinity of the medium compared to Calen. (AU)

• FAPESP's process: 18/16848-2 - Biological and physicochemical properties evaluation of a bioceramic-based intracanal medication BIO-C temp
• Grantee: Camila Soares Lopes
• Support Opportunities: Scholarships in Brazil - Doctorate