CAVEAT LECTOR/READER BEWARE!... UCLA Comparative Study of Core-Vent vs. Branemark Implants: Subsequent Niznick declaration in 1996 litigation documents the misuse of criteria and failure to report on consecutively placed implants to bias results of the 1987 study. Excerpts of articles by Albrektsson and Sennerby that misquote UCLA study to promote Branemark System
Abstract No. 83
-Moy P.K., Buemer J., and Lewis S.
Comparative Analysis of One Hundred Consecutively Placed Core-Vents to One
Hundred Consecutively Placed Biotes Implants
Private Practice
Los Angeles, CA

To date, many articles have been published stating the success and/or failure rates of a particular endosseous implant system based upon an individual clinician's experience. However, there are no reports of a comparison between different systems and the clinician's success with the different systems. The purpose of this analysis is to compare the success rate of the two systems based on a single practitioner's experience. In this manner, the same surgical technique, experience and postoperative care were used on all patients reviewed, assuring minimal variations and discrepancies that may be found when comparing one clinician's data to another. Failures will be defined and identified according to jaw position, timing of failure and treatment outcome. Complications associated with the two systems will also be discussed.
Read Dr. Niznick's Declaration Analyzing Results!
Albrektsson T, Lekholm U. Osseointegration: Current state of the art. Dent Clinics North Am 1989;33(4):537-554:

The findings of Moy53 have recently been backed up by Malmquist and Sennerby,50 [cited as an "Unpublished manuscript, 1989"] the first authors to present a detailed analysis on the outcome of the Core Vent implant.
Malmqvist J, Sennerby L: A clinical report on the success of 47 consecutively inserted Core-Vent implants followed from 3 months to 4 years. Int J Oral Maxillofac Implants 1990;5(3):53-60 (Read Dr. Niznick's Response!):

  Moy7 includes dianostic criteria such as looseness, radiolucency, mobility, or chronic infection in his assessment. He reports that 13 of 31 maxillary and 22 of 69 mandibular implants were found to be failures, resulting in a total success rate of 58% (maxilla) and 68% (mandible) for a follow-up of 0 to 3 years. This is in line with our observations, since our total 0- to 3-year sucess was approximately 56%, with most of the implants judged as failures during the fourth year after placement (Tables 7 and 8). Furthermore, Moy7 also placed 101 consectuive Branemark implants and, using the same criteria, the success rate was 92% (maxilla) and 96% (mandible) over a follow-up period of 0 to 2 years.

Read Published Letter to Editor on Malmquist, Sennerby article

Albrektsson T, Sennerby L. Direct bone anchorage of oral implants: Clinical and experimental considerations of the concept of osseointegration. Int J Prosthodont 1990;3(1):30-41.

  If the bone resorption process continues with the implant in situ, the implant must be removed to prevent further deterioration of the tissues. By postponing implant removal in such situations, implant survival rates become falsely high for a few years, during which the patient's surrounding bone complex may suffer irreparable injury. This criticism is valid for stable as well as unstable implants. Two independent studies13 [Moy], 14 [Malmqvist and Sennerby, 1990] of 100 and 47 consecutively placed Core-Vent implants, respectively, have demonstrated an unacceptable bone loss around these devices, leading to actual success rates of 50% to 60% or lower when followed for less than 5 years. The Core-Vent implant has been experimentally demonstrated to be osseointegraed14 with the simple definition given above.14 [Malmqvist and Sennerby, 1990]

Albrektsson T, Zarb GA. Current interpretations of the osseointegrated response: Clinical significance. Int J Prosthodont 1993;6(2):95-105.

For example, in their study of 1,732 consecutively inserted Core-Vent implants with an average follow-up of 27 months, Patrick et al.55 did not report on stability tests or bone height measurements performed. Therefore, the literature is presently restricted to two other independent Core-Vent reports (Moy56 and Malmquist and Sennerby57 ), both of which reported a dramatic bone loss around Core-Vent devicess (Figs 3a and 3b). Disregarding the already removed implants in the study by Malmquist and Sennerby,57 there was a reported average bone loss over 27 months (the same average follow-up time as in the study by Patrick et al.55 ) of about 4 mm.