Mechanical and Physical Properties of Vital Pulp Therapy Materials

Objectives:   To measure the compressive strength of three pulp capping materials at 3 times and record the marginal seal of Biodentine and N'Durance resin-based composite at the tooth-restoration interface. Methods: Compressive Strength: Samples (n=10) of Biodentine, MTA, and Dycal/LD Caulk were prepared using Teflon cylinder molds (d=4/h=8mm), stored (37°C/distilled water) and loaded until failure (1mm/min) using Instron (Model/5565) at 35minutes, 24hours, and 28days. Microleakage: Class I preparations were placed in fifteen extracted, intact, human molars and randomly divided into 3 groups (n=5). Cavities were restored with Biodentine or N'Durance, or Biodentine+N'Durance. Single Bond Plus adhesive/3M ESPE was used to bond N'Durance to tooth. Biodentine+N'Durance samples were prepared with Biodentine filling the occlusal preparation, stored (37°C/distilled water/48hours) then the occlusal ½ of Biodentine was removed and restored with N'Durance/Single Bond Plus and incubated (37°C/distilled water/24 hours). N'Durance and Biodentine+N'Durance samples were finished with magnification. Microleakage was measured by applying nail varnished except for 2mm adjacent to the restoration and placing the specimens into 2% methylene blue solution for 3hrs. Samples were sectioned axially through the restorations and wet ground (600/1000/2000-grit SiC paper). Dye penetration was classified into 0 no leakage, 1 leakage into enamel and 2 leakage into dentin. Twenty readings were obtained for each group. Data were analyzed using ANOVA and Tukey-Kramer post-hoc tests or (leakage) Kruskal Wallace test (p=0.05).

Results: (Mean±SD)

Material/Manufacturer	Compressive Strength-MPa
	35-minutes	24-hours	28-days
Biodentine/Septodont	10.6±2	57.1±12	72.6±8
Dycal/Dentsply	9.2±1	17±1	14.3±4
MTA/Dentsply	0.007±0.015	8.5±2	37.1±12

 

Material	Score/# of readings
	0	1	2
Biodentine	20	0	0
N'Durance	7	7	6
Biodentine+N'Durance	11	8	1

Conclusion: Biodentine was significantly stronger than MTA at all time periods (p<.05) and should support occlusal forces for a short time as well as provide an effective seal. This study was supported by NIDCR 5T32DE017607-DART