Radiographic evaluation of immediately loaded implants supporting 2-3 units fixed bridges in the posterior maxilla: a 3-year follow-up prospective randomized controlled multicenter clinical study

Clin Oral Implants Res. 2016 Apr;27(4):399-405. doi: 10.1111/clr.12565. Epub 2015 Feb 9.


Objective: To compare the survival rate and alveolar bone levels at implants installed in healed sites and functionally loaded within 1 h from installation or after 3 months.

Material and methods: A total of 30 patients (17 male and 13 female) were recruited and 71 implants with a SLA(®) surface, 4.1 mm in diameter and 8-12 mm long, were installed in a fully healed alveolar ridge, 36 as test and 35 as control implants. The test implants were immediately loaded with a temporary reconstruction in proper occlusion, while the randomly selected control sites received the final reconstruction after 3 months. Radiographic bone levels were determined after implant installation, prosthesis delivery, and at annual intervals thereafter.

Results: One patient of the control and one patient of the test were excluded from evaluation. No further losses of implants or patients were seen up to the 3-year follow-up. Hence, data from 28 patients were accounted for. A total of 37 and 36 metal-ceramic crowns were provided at the test and control sites, respectively. No biological and technical complications were observed during the 3-year follow-up. Bone levels at the time of implant installation were at 1.6 ± 0.8 and 1.7 ± 0.9 mm from the implant shoulder at the test and control sites, respectively. At prosthesis delivery, the bone levels were located at 2.4 ± 0.7 mm at the control sites 3 months after implant placement. After 1 year of function, similar bone levels were observed at both sites, displaying 2.4 ± 1.0 and 2.5 ± 0.8 mm at the test and control sites, respectively. No differences were found in the subsequent observation periods.

Conclusion: Survival rates and radiographic bone levels after 1, 2, and 3 years of observation did not differ between conventionally installed implants loaded immediately or delayed (after 3 months). Moreover, insertion torque values did not affect osseointegration.

Keywords: SLA surface; dental implants; immediate loading; prospective randomized study.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alveolar Bone Loss / diagnostic imaging*
  • Alveolar Bone Loss / etiology
  • Dental Implantation, Endosseous* / adverse effects
  • Dental Prosthesis, Implant-Supported* / adverse effects
  • Denture, Partial, Fixed* / adverse effects
  • Female
  • Follow-Up Studies
  • Humans
  • Immediate Dental Implant Loading*
  • Male
  • Maxilla / diagnostic imaging
  • Maxilla / surgery
  • Prospective Studies
  • Tooth Socket / diagnostic imaging
  • Tooth Socket / surgery