Date Published: February 21, 2017
Publisher: Public Library of Science
Author(s): Rudolf Seemann, Alexander Jirku, Florian Wagner, Arno Wutzl, Sompop Bencharit.
The aim of this study was to evaluate the influence of implant diameter, length and shape on a surrogate parameter of implant survival; i.e. the implant return rate in a big data analysis.
A retrospective study was conducted and the factors influencing the success rates of 69,377 sold implants over a seven-year period were evaluated. The osseointegration program of a reseller provides reliable data of a single country. Implant loss rates were investigated using logistic regression models and regressed by implant type, diameter, and length.
The return rate of 69,377 sold implants was 2.78% and comparable to implant loss rates in previous published prospective studies as its surrogate parameter. A total of 80% of implant returns had occurred within 157 days, and an additional 15% within 750.25 days. Diameters of 3.8 to 5.0mm showed the lowest return rates with its bottom in the 4.3mm implant whilst 6.0mm implants had significantly higher return rates. In comparison to the most sold implant length (13mm) shorter implants showed significantly higher early return rates.
The study provides evidence that in cases of standard indications and sufficient bone, the use of screw typed dental implants with 3.8 or 4.3 diameter and 11 or 13 mm length shows the lowest implant return rates. Other implants may be selected only in specific indications.
The history of dental implants shows a steady increase in cumulative survival rates (CSR). In the nineties a successful implant was defined as one with a 5-year CSR of 89.9% . However, dental implantology has currently achieved a 5-year CSR of 97.2% (95% CI 96.3–97.9%) in implant-supported single crowns , and 95.6% in implant-supported fixed dental prostheses . Although the quest for higher success rates in the last few years has led to no more than the production of a titanium screw, it has been substantially improved by subtle modification of its microgeometry and nanogeometry. The platform switch reduces marginal bone loss compared to platform match abutments  without improving the implant success rate . In addition to being visible to the naked eye, the properties of the implant have been altered on the microscale and even nanoscale level. A number of surface treatments including sandblasting, etching, coating, UV irradiation, helium irradiation, and ion implantation have improved osseointegration and enhanced success rates .
We evaluated the factors influencing the success rates of the implants provided by one reseller (Altatec GmbH, Wimsheim, Germany) over a seven-year period (2007–2013) in one country (Austria).
A total of 69,377 sold implants were included in this study. Of these, 11,220 were RL implants, 32,775 SLP, and 25,382 SLPp. Of the 69,377 implants, 2.78% (n = 1,928) were returned due to loss. Of the returned implants 225 were excluded due to missing information: 182 multiple losses with ambiguous mention of diameter and length, and 43 due to missing implantation or explantation date. The excluded implants accounted for nearly equal fractions in the implant lines: 0.39% of Root-Line implants, 0.36% of Screw-Line implants, and 0.24% of Screw-Plus implants. All 1703 implant returns, accounting for 88.3% of all returns, qualified for the 10-Year Osseointegration Guarantee Program and were finally included in the analysis. Sales data were corrected to reflect the true implant return rate of 2.78% by scaling the sold number of implants with a correction factor resembling the fraction of included returns (Root 0.895, Screw 0.847, Screw+ 0.893).
A total of 69,377 sold implants were included in this study. Compared to other studies, this is the highest ever published number of implants that have been followed up. With regard to primary implant failure (type A–within the first 157 days), the implant with the highest probability of success (no return) was the 4.3 x 13 mm screw-type implant.