Related Experiment Video
Updated: Apr 15, 2026
Real-Time Dynamic Navigation System for the Precise Quad-Zygomatic Implant Placement in a Patient with a Severely Atrophic Maxilla
Published on: October 18, 2021
Crestal bone changes in macrogeometrically similar implants with the implant-abutment connection at the crestal bone
Paul van Eekeren1, Ali Tahmaseb1, Daniël Wismeijer1
1Section of Oral Implantology and Fixed Prosthetics, Department of Oral Function, Academic Centre of Dentistry Amsterdam, Amsterdam, The Netherlands.
Objective:
Crestal bone loss around dental implants is a criterion for success as this could prevent loss of implant and superstructure. The macrogeometry of the implant could influence bone remodelling when the implant-abutment connection is placed at crestal bone level or above. The aim of this study was to evaluate crestal bone remodelling in a randomized clinical prospective trial in macrogeometrically similar implants with the prosthetic connection at the crestal bone level and 2.5 mm above. The null hypothesis was that there was no difference in crestal bone loss after 1 year of early loading.
Material And Methods:
Patients were referred to Academic Centre of Dentistry Amsterdam for implant placement. Patients were subjected to inclusion and exclusion criteria and received a minimum of two implants: an implant with the prosthetic abutment connection at the crestal bone level (minimized collar [MC], bone level) and one with the prosthetic abutment connection 2.5 mm supracrestal (long collar [LC], tissue level). The mesial or distal location of each implant type was blinded for the patient and randomized. The implants were loaded splinted after 3 weeks of healing. The primary outcome was bone-level change assessed after 1 year of loading.
Results:
Thirty-three patients fulfilled the inclusion criteria. Thirty-nine Thommen SPI ELEMENT LC implants and 39 MC were placed, and each fixed dental prosthesis was supported by one LC and one MC implant. The intraclass correlation of measures performed by the first and second X-ray examiner was as follows: on the mesial side of the MC implant 0.990 (0.980-0.995; 95% confidence interval [CI]), 0.980 (0.962-0.990; 95% CI) on the distal side of the MC implant, 0.979 (0.959-0.989; 95% CI) and 0.988 (0.978-0.994; 95% CI) on the mesial and distal side of the LC implant, respectively. The mean bone loss of the MC implant was 0.4 ± 0.4 mm. The mean bone loss of the LC implant was 0.2 ± 0.5 mm. The paired samples t-test showed a statistically significant difference (P < 0.05) between the MC and LC implants.
Conclusion:
Dental implants at bone level show statistically significantly (P < 0.05) more crestal bone change after 1 year of loading than a tissue-level implant.
Related Concept Videos
01:14Cranial Bones: Superior and Posterior View
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
01:27Cranial Bones: Lateral View
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...