Simplified methods of implant treatment in the edentulous lower jaw: a 3-year follow-up report of a controlled prospective study of one-stage versus two-stage surgery and early loading.
BACKGROUND
Interest in the use of one-stage surgery and immediate loading of oral implants has lately been increasing.


OBJECTIVE
The aim of this study was to compare the 3-year results of one-stage surgery versus two-stage surgery, early loading versus loading after a 3-month healing period, and the use of one-piece implants versus the use of two-piece implants.


METHODS
The study included 108 patients with edentulous mandibles. Each patient was treated with four Brånemark System implants (Nobel Biocare AB, Göteborg, Sweden) and with full fixed prostheses. Patients were consecutively treated and were distributed in four groups: group A (one-stage surgery), group B (control group with two-stage surgery), group C (one-piece implants), and group D (early loading). In groups A and B Brånemark Standard implants and standard abutments were used. In group C the conical one-piece Brånemark implant was used, and in group D the patients had Brånemark System Mk III implants together with multiunit abutments. All patients were observed for 3 years.


RESULTS
Of the 432 inserted implants, 24 were lost. Survival rates in the three experimental groups ranged from 93.2 to 93.3% whereas the survival rate in group B (the control group with two-stage surgery) was 97.5%. The differences between the groups were not statistically significant. The changes in marginal bone level were measured from fixture insertion to the final follow-up at 3 years. The bone loss in group D (early loading) was significantly less than in group B (the control group) whereas there were no differences in marginal bone change between the other groups.


CONCLUSIONS
Early loading seemed to give good results in the anterior part of the mandible. The survival rate of the early-loaded implants did not significantly differ from that of implants inserted with the conventional two-stage procedure, but the mean marginal bone loss around the surviving implants was less with early loading.
Engquist
Bo
B
Department of Prosthodontics, Specialist Center Oral Rehabilitation, SE-58185 Linköping, Sweden. ebest@telia.com
Astrand
Per
P
Anzén
Bengt
B
Dahlgren
Simon
S
Engquist
Eva
E
Feldmann
Hartmut
H
Karlsson
Ulf
U
Nord
Per-Gunnar
PG
Sahlholm
Sten
S
Svärdström
Pia
P
D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000209:etiology; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007575:Jaw, Edentulous / Q000534:rehabilitation* / Q000601:surgery; D008297:Male; D008334:Mandible / Q000601:surgery; D008875:Middle Aged; D011446:Prospective Studies; D018709:Statistics, Nonparametric
D015921:Dental Implants