IADR Abstract Archives
Interaction of Pulp Capping Materials With Caries Affected Dentine
Objectives: To assess (i) mechanical, chemical and microstructural characteristics of sound coronal dentine and caries affected dentine (CAD) using different dentine conditioning protocols, and (ii) structural changes of dentine-material interface following application of pulp capping materials on conditioned CAD.
Methods: Five dentine conditioning protocols: 2.5% sodium hypochlorite (NaOCl), 17% ethylene diamine tetraacetic acid (EDTA), 37% phosphoric acid gel, 10% polyacrylic acid or distilled water, were used to aid smear layer removal. Dentine sections obtained from the coronal part of human teeth were assessed pre- and post-conditioning by Vickers microhardness (VH), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Five pulp capping materials were used (MTA ANGELUS®, Biodentine®, Bio-C PULPO, GC Fuji IX GP® and Endosequence® BC linerTM) on CAD sections following application of conditioning protocols. After 28 days in Hank’s balanced salt solution, the material interaction with conditioned CAD was assessed by SEM, elemental mapping, and microhardness of dentine at 25 and 100 microns from the interface. Statistical analysis was conducted using ANOVA followed by Bonferroni post hoc to detect the difference between groups (p-value < 0.05).
Results: SEM/EDS analysis showed that the use of NaOCl and distilled water did not remove the smear layer while other protocols resulted in depletion of calcium. Elemental mapping showed that calcium was found in the materials and dentine, and silicon migrated from material to dentine, in all groups. Regardless of the conditioning protocol, MTA, Fuji IX and BC liner exhibited aluminium migration, and BC liner showed fluoride migration to dentine. There was an increase of CAD microhardness at 25 microns after material placement (52 - 65 HV).
Conclusions: EDTA conditioning can be used as an alternative to acids as it leaves a smear-free dentine surface. The interaction of pulp capping material with conditioned CAD occurred through minerals exchange. The presence of a smear layer did not impede the interaction.
Methods: Five dentine conditioning protocols: 2.5% sodium hypochlorite (NaOCl), 17% ethylene diamine tetraacetic acid (EDTA), 37% phosphoric acid gel, 10% polyacrylic acid or distilled water, were used to aid smear layer removal. Dentine sections obtained from the coronal part of human teeth were assessed pre- and post-conditioning by Vickers microhardness (VH), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Five pulp capping materials were used (MTA ANGELUS®, Biodentine®, Bio-C PULPO, GC Fuji IX GP® and Endosequence® BC linerTM) on CAD sections following application of conditioning protocols. After 28 days in Hank’s balanced salt solution, the material interaction with conditioned CAD was assessed by SEM, elemental mapping, and microhardness of dentine at 25 and 100 microns from the interface. Statistical analysis was conducted using ANOVA followed by Bonferroni post hoc to detect the difference between groups (p-value < 0.05).
Results: SEM/EDS analysis showed that the use of NaOCl and distilled water did not remove the smear layer while other protocols resulted in depletion of calcium. Elemental mapping showed that calcium was found in the materials and dentine, and silicon migrated from material to dentine, in all groups. Regardless of the conditioning protocol, MTA, Fuji IX and BC liner exhibited aluminium migration, and BC liner showed fluoride migration to dentine. There was an increase of CAD microhardness at 25 microns after material placement (52 - 65 HV).
Conclusions: EDTA conditioning can be used as an alternative to acids as it leaves a smear-free dentine surface. The interaction of pulp capping material with conditioned CAD occurred through minerals exchange. The presence of a smear layer did not impede the interaction.