Micro-CT observations of the adaptation at gingival wall in ClassⅡrestorations with different dental restorative materials / 北京大学学报(医学版)

ABSTRACT

Objective: To evaluate the adaptation of different materials for gingival layer in Class Ⅱrestorations using Micro-CT.Methods:Eighteen extracted human premolars were selected, and ClassⅡcavities were prepared.The teeth were randomly divided into six groups and restored using layering tech-nique.Six materials were used for gingival layer, including four injectable materialsBeautifil Flow Plus F00 (F00), Beautifil Flow F10 (F10), Filtek Z350 Flowable (Z350F), FujiⅡLC CAPSULE (Fuji), and two packable materials BeautifilⅡ (BF), Filtek Z350 (Z350).The restored teeth were scanned with micro-CT and the images were 3D reconstructed to evaluate the volumes and the distribution of the voids on the restoration-tooth interface of the gingival layer.The volume of the voids were statistically analyzed using nonparametric Jonckheere-Terpstra tests.Results: The volumes ( mm3 ) of the voids on the restoration-tooth interface were Z350F (0.000 15), F10 (0.000 39), F00 (0.012), Fuji (0.070), Z350 (0.16) and BF (0.20).There were significant differences between Z350F/F10 and Fuji/Z350/BF (P<0.05).Most of the voids were found on the point-line angles of the cavities.Con-clusionThe voids on the restoration-tooth interface were mainly on the point-line angles of the cavities. Injectable materials with high flowablility could reduce the restoration-tooth interface voids significantly when used for the gingival layer in ClassⅡrestorations.