Paul Darius

A study of 589 consecutive implants supporting complete fixed prostheses. Part II: Prosthetic aspects

In 91 consecutive edentulous patients, 103 jaws were treated with complete fixed prostheses supported by Brånemark Implants (n = 589). As a result of fixture loss in each of two patients (two jaws), an overdenture instead of a fixed prosthesis was installed. For one patient (two jaws), data were not available after abutment connection. At the end of the seventh year, the cumulative failure rates for the remaining 99 prostheses reached 4.9% for mandibles and 10.1% for maxillae. After loading, 12 fixtures showed signs of nonintegration, but only one patient had to revert to complete dentures. Neither the fixture location nor the cantilever length revealed a significant difference in marginal bone loss around the supporting fixtures. Patients with fixture-supported fixed prostheses in both jaws showed significantly more marginal bone loss than did those with only one fixed prosthesis opposed by either natural dentition (50%) or a complete denture (50%). Component complications were limited to fixture fracture (3/564), abutment screw fracture (5/564), and gold screw fracture (7/564). The predictability of Brånemark implants in the treatment of completely edentulous jaws is confirmed.

The Influence of Surface Free-energy on Planimetric Plaque Growth in Man

The purpose of this study was to examine the change in plaque area over nine days in vivo on four materials with different surface free-energies (s.f.e.). Twelve healthy dental students participated in a crossover, split-mouth, double-blind study. Supragingival plaque formation was recorded over a nine-day period, on four different materials: fluorethylenepropylene (Teflon) (FEP), parafilm (PAR), cellulose acetate (CA), and enamel (E) with s.fe. of 20, 26, 57, and 88 erg/cm2, respectively. Strips made from the first three materials were stuck to the buccal surface of an upper incisor. The remaining incisor was carefully polished and served as an enamel surface. The increase in plaque was evaluated after three, six, and nine days. A planimetrical analysis was used so that the plaque area could be expressed as a percentage of the total buccal tooth surface. This procedure was repeated on each subject, so that at the end, each pair of central or lateral incisors received the four tested materials. The results indicated that the adherence of micro-organisms on pellicle-coated substrata was influenced by the materials s.f.e.; there was an association between the s.f.e. of the substrata and the supragingival plaque extension in vivo. High surface free-energy substrata in the oral cavity attracted more micro-organisms than did low energetic materials. Additionally, the bacterial adhesion seemed very weak on surfaces with a low s.f.e.

A six-year prosthodontic study of 509 consecutively inserted implants for the treatment of partial edentulism

A total of 509 consecutive Brånemark TM implants (Nobelpharma AB, Gothenburg, Sweden) were inserted in 146 patients between December 1982 and May 1989, on which 217 fixed partial dentures were planned. The cumulative failure rates after abutment connection were 3.9% and 4.1% for the maxillae and mandible, respectively. The lack of continuous prosthesis stability was limited to 4.1% for the maxillae and 5.4% for the mandible. The average annual marginal bone loss was 0.77 mm (SD = 1.0) and 0.96 mm (SD = 0.9) for the maxillae and mandible, respectively, during the first year and averaged 0.1 mm for the following years. The mode of connection between teeth and implants or the use of porcelain instead of composite resin as occlusal material did not influence the marginal bone height around the implants. Technical complications were most often related to the materials used. The results of a medium-term follow-up encourage the use of the Brånemark osseointegration system in the treatment of partial edentulism.