Objective: The objective of this preclinical study was to evaluate a predictable technique that combines layering and injection moulding for easy, efficient and consistent polychromatic anterior restorations.
Materials and Methods: This preclinical study was conducted on a Nissin Jaw Model with push-type typodont. Thirty maxillary anterior typodonts were prepared using diamond abrasives to simulate multiple diastemata and divided into equal groups. Group A was restored using the traditional injection moulding technique and Group B was restored using the experimental technique, which combines the histological layering technique with the traditional injection moulding technique.
Unprepared typodonts were used as a laboratory wax up for consistency and reproducibility. Stents were prepared using a clear, vinyl polysiloxane impression material. Samples of Group A were restored with G-ænial Universal Flo after adhesive protocol. For Group B, after adhesive protocol, packable composite (Shades A3, A2, A1, CT) was used to create internal anatomical features such as mamelons, incisal halo, and cervical high value areas, following which G-ænial Universal Flo was injected to mimic the enamel layer.
Standardised finishing and polishing protocols were followed for both groups. An aesthetic evaluation was performed by blinded evaluators using the FDI World Dental Federation clinical criteria for direct restorations. The parameters considered were surface luster, translucency, and aesthetic anatomical form.
Results: The surface luster of both groups was comparable; Group B received better scores for translucency and aesthetic anatomical form.
Conclusion: This preclinical study demonstrated that layering followed by injection moulding resulted in predictable, aesthetic, polychromatic, life-like restorations.
Keywords: adhesives, composite resins, dental bonding, aesthetics, injection moulding, layering