AUTHOR=Hobbi Paniz , Ordueri Tugce Merve , Öztürk-Bozkurt Funda , Toz-Akalın Tugba , Ateş Muzaffer , Özcan Mutlu 

TITLE=3D-printed resin composite posterior fixed dental prosthesis: a prospective clinical trial up to 1 year

JOURNAL=Frontiers in Dental Medicine

VOLUME=Volume 5 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/dental-medicine/articles/10.3389/fdmed.2024.1390600

DOI=10.3389/fdmed.2024.1390600

ISSN=2673-4915

ABSTRACT=Objectives: This clinical trial evaluated the clinical behaviour of 3D printed posterior resin composite fixed dental prosthesis.Materials and Methods: Between 10.10.2020 -05.08.2022, forty-nine patients aged between 19 and 60 years old (33 females, 16 males) received 68 3D printed resin composite 3-unit posterior fixed dental prostheses (ELS Even Stronger, Saremco, Switzerland). FDPs were followed up to 2 weeks after placement (baseline), 6 months after placement, and 1 year after placement by two independent calibrated observers using modified FDI criteria for anatomical form, secondary caries, marginal adaptation, surface roughness, colour match, fracture of material, staining surface, staining margin, approximate anatomical form, retention, gingival health, and patient's view. Survival analyses were performed using Kaplan-Meier.Results: A total of 59 restorations were evaluated and the mean observation period was 8.63 months. Failure types were categorized as mechanical and biological. Failures were observed in 14 FDPs. 9 FDPs showed mechanical failure and 5 FDPs showed biological failure. Mechanical failures were mostly experienced as connector fractures.Eight FDPs showed cohesive fractures (7 in a single connector at either at the mesial or distal and 1 in the pontic itself). Biological failures, including root canal treatment and gingival tissue reactions, were observed within the first six months. Based on mechanical failures, the survival rate was 86.7% while including the biological complications, this corresponded to 71.6% (Kaplan-Meier). After one year, 2 FDPs showed surface luster loss (Score 4), 2 colour mismatches (Score 4), 2-surface staining (Score 4).Conclusion: 3D printed resin composite FDPs were observed acceptable after 1 year of clinical follow-up, providing that the experienced failure types were mainly associated with fractures in the connector region which requires revision of design parameters.Clinical Relevance: The material used is indicated for permanent crowns and temporary bridges but the material tested may benefit from improvements in the design of connectors as the early observations were not failure-free.