Direct loading of Nobel Direct and Nobel Perfect one-piece implants: a 1-year prospective clinical and radiographic study.
OBJECTIVE
The aim of this prospective study was to evaluate the Nobel Direct and Nobel Perfect one-piece implants (OPIs) when used for immediate function.


METHODS
Forty-eight patients were provided with 115 OPIs for loading with a provisional crown or a bridge within 24 h and followed for at least 12 months with clinical and radiographic examinations. A group of 97 patients previously treated under identical conditions by the same team with 380 two-piece implants (TPIs) for immediate loading in the mandible and maxilla served as the reference group.


RESULTS
Six (5.2%) OPIs failed during the follow-up due to extensive bone loss. Five (1.3%) implants failed in the reference group. After 1 year, the mean marginal bone loss was 2.1 mm (SD 1.3) for OPIs and 0.8 mm (SD 1) for TPIs. 20% of OPIs showed more than 3 mm of bone loss compared with 0.6% for TPIs. When compensating for vertical placement depth, OPIs still showed a lower marginal bone level and thus more exposed threads than TPIs. Depending on the criteria used, the success rate for OPIs was 46.1% or 72.2% compared with 85% or 91.6% for TPIs.


CONCLUSIONS
The Nobel Direct and Nobel Perfect OPIs show lower success rates and more bone resorption than TPIs after 1 year in function. Factors such as implant design, insertion depth, rough surface towards the mucosa, in situ preparation and immediate loading may have an influence on the clinical outcome.
Ostman
Per-Olov
PO
Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Sweden. po.ostman@telia.com
Hellman
Mats
M
Albrektsson
Tomas
T
Sennerby
Lars
L
D000368:Aged; D016301:Alveolar Bone Loss / Q000209:etiology*; D003758:Dental Implantation, Endosseous; D015921:Dental Implants / Q000009:adverse effects*; D017267:Dental Prosthesis Design / Q000009:adverse effects; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003831:Denture, Partial, Immediate; D005260:Female; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography
D015921:Dental Implants