Randomized clinical split-mouth study on a self-adhesive vs. a conventional bulk-fill composite in class II cavities: Results after five years.

Abstract

Aim: In this randomized prospective split-mouth study, the clinical survival and performance of a novel not yet commercially available self-adhesive dual-curing bulk-fill restorative material (SA, Solventum) and a conventional bulk-fill composite (Filtek One, Solventum; FO) were examined for restoration of class II cavities over a period of 60 months.

Methods: 30 patients underwent the placement of one SA and one FO restoration each. FO restorations were bonded using Scotchbond Universal (Solventum) in self-etch mode, while SA was applied without adhesive. This publication reports restoration survival as a primary outcome and quality parameters of restorations according to FDI criteria as a secondary outcome at baseline, 48 and 60 months. Restorations were evaluated by two independent examiners. Kaplan-Meier survival analysis and non-parametric statistical methods were employed (χ²-tests; α=0.05).The study was registered prior to commencement (German Register of Clinical Studies: DRKS00013564).

Results: 25 patients out of initially 30 were available at 60-mo recall. At 60-mo, FO exhibited a clinical survival rate of 97.1% and SA of 98.9% without significant difference (p>0.05). All restorations available for clinical evaluation maintained clinically acceptable FDI scores throughout the follow-up period. FO significantly outperformed SA in terms of surface luster, color match and translucency at both evaluation time points, in terms of marginal staining at 60-mo and in terms of surface staining at 48-mo. Surface luster, surface staining and marginal adaptation deteriorated over time for both materials.

Conclusions: Both materials demonstrated similar clinical survival and performance over 60 months, which is to date the longest observation period for a clinical study including a self-adhesive bulk-fill restorative. SA displayed slightly inferior but clinically acceptable esthetic properties compared to FO. Both materials exhibited clinically acceptable outcomes over 60 months, warranting their recommendation for clinical use.

Clinical significance: The novel self-adhesive dual-curing bulk-fill restorative material exhibited clinically acceptable outcomes over 60 months, similarly to a conventional bulk-fill restorative used with a universal adhesive, with only minor cutbacks in esthetic properties. Thus, both materials can be considered suitable for clinical application.