Influence of dentin pretreatment with 2.5% titanium tetrafluoride on inhibiting caries at the tooth-restoration interface in situ.

OBJECTIVE: Investigate the effects of dentin pretreatment with 2.5% titanium tetrafluoride (TiF4 ) aqueous solution followed by two-step self-etching (CLE/Clearfil SE Bond) and one-step self-etching adhesive systems (SBU/Single Bond Universal) on carious lesion inhibition at the tooth-restoration interface using an in situ model.

DESIGN: Sixty-four cavities at the enamel-dentin junction of dental fragments were randomly distributed according to groups (n=16): 1) TiF4 +CLE; 2) TiF4 +SBU; 3) CLE; 4) SBU. Cavities were restored using resin composite, and placed in intraoral palatal devices used by 16 volunteers for 21days, to induce caries formation in situ. The fragments were then ground-flat to perform Knoop microhardness tests. Nine indentations were performed on each enamel and dentin substrate, subjacent to the restoration. Analysis of variance and Tukey's test were applied.

RESULTS: Enamel: groups receiving TiF4 dentin pretreatment (regardless of adhesive system and tooth-restoration interface distance) presented higher hardness means at a depth of 25μm from the outer tooth surface (p<0.0001). Dentin: groups receiving CLE presented higher means when applying TiF4 pretreatment, whereas groups restored with SBU presented higher means without pretreatment (p=0.0003).

CONCLUSIONS: Dentin pretreatment with TiF4 inhibited demineralization of the enamel interface in situ, regardless of the adhesive, and TiF4 pretreatment followed by CLE application showed higher potential for inhibiting dentin demineralization at the interface.