Single posterior implant-supported restorations fabricated using a scannable healing abutment versus a conventional scan body: A randomized controlled trial

Abstract

Statement of problemThe use of a scannable healing abutment is a convenient option for fabricating implant-supported restorations (ISRs) with a digital workflow; however, clinical studies evaluating prosthetic efficacy are lacking. PurposeThe purpose of this randomized controlled trial was to investigate the prosthetic efficacy of definitive posterior single ISRs fabricated after scanning using a scannable healing abutment-scan peg (SHA-SP) in comparison with a conventional scan body (CSB). The time for data acquisition, quality of proximal and occlusal contacts, and relative occlusal force of ISRs were measured. Material and methodsTwenty-four participants eligible for single ISRs to replace the mandibular first molar with adjacent and antagonist teeth present were randomly allocated to either a study group (n=12) receiving ISRs after intraoral scanning using an SHA-SP or a control group (n=12) receiving ISRs after intraoral scanning using CSB. During the surgical procedure, a prefabricated contoured scannable healing abutment was screwed to the implant in the SHA-SP group, while a custom-made healing abutment was used in the CSB group. After a healing period of 3 months, an intraoral scan was made, and the duration of data acquisition was recorded. The ISRs were milled from zirconia and evaluated for the quality of proximal and occlusal contacts using dental floss and shim stock, respectively. The relative occlusal forces of the ISRs and their contralateral natural teeth were measured using a digital occlusal analyzer. Statistical analysis was done using an independent sample t test for quantitative variables and a Pearson chi-squared test for qualitative variables between the tested groups (α=.05). ResultsThe direct digital workflow using SHA-SP was statistically less time consuming than the CSB (P<.001). The 2 groups were statistically similar regarding the quality of the proximal contacts (P=.281) or occlusal contacts (P=.307) and the relative occlusal forces of ISRs (P=.315). The relative occlusal forces of the ISRs in both groups were significantly lower than those of their contralateral natural teeth (P<.001). ConclusionsDirect digital workflow using SHA-SP was more rapid, saving clinical chairside time, and produced proximal and occlusal contacts of comparable quality with those obtained with CSB. The relative occlusal forces of ISRs in both workflows were lower than their contralateral natural teeth.