Related Experiment Video
Updated: May 2, 2026
Measuring the Complete-arch Distortion of an Optical Dental Impression
Published on: May 30, 2019
Digital Quantitative Analysis of Occlusal and Morphologic Characteristics of Mandibular First Molar Implant
Purpose:
To quantitatively compare the occlusal characteristics after delivery of mandibular first molar implant prostheses fabricated via a fully digital workflow with the occlusal characteristics of contralateral teeth.
Materials And Methods:
A total of 40 patients who had undergone single mandibular first molar implant surgery were enrolled. A fully digital workflow was employed to fabricate prostheses with titanium abutments and zirconia crowns, with crown morphologic data sourced from the software's built-in database. Standardized occlusal adjustments were performed after prosthesis delivery. The posterior regions on the implant side (pre- and post-adjustment, P1 and P2) and on the contralateral side (T) were intraorally scanned. By analyzing the average occlusal clearance (AOC), the minimum occlusal clearance (MOC), and the inclination of cusps (IC), the occlusal and morphologic features of implant prostheses were compared to those of contralateral teeth. Additionally, the vertical occlusal adjustment amount (VOAA) of implant prostheses was measured.
Results:
The AOC-P2 was 152.11 ± 61.34 μm, and the MOC-P2 was 123.43 ± 58.89 μm; the ΔAOC(P2-T) was 95.03 ± 70.35 μm, and the ΔMOC(P2-T) was 115.14 ± 61.60 μm. The mean inclination of all five cusps at P1 and P2 was 25.96 ± 3.77 degrees and 17.39 ± 3.19 degrees, respectively (P < .001), with a mean ICA-P2/ICA-T ratio of 0.89 ± 0.24. The mean inclination of the functional cusps at P2 was 18.81 ± 5.04 degrees (ICF-P2/ICF-T: 1.08 ± 0.53), and the mean inclination of the nonfunctional cusps was 15.26 ± 3.56 degrees (ICNF-P2/ICNF-T: 0.79 ± 0.39). The average VOAA was 110.89 ± 56.72 μm.
Conclusions:
The occlusal clearance of the implant prosthesis post-adjustment was approximately 100 μm greater than that of the contralateral tooth, and the IC was about 89% compared to the contralateral tooth. These findings provide a theoretical foundation for the accurate digital occlusal design of single posterior implant prostheses in a fully digital workflow. The tooth morphology database for this specific software may require additional modification to be used in the fabrication of implant restorations, especially through reduction of nonfunctional IC. Additionally, establishing a dedicated database for implant restoration fabrication is essential.
