Fixed Dental Prosthesis on 4.2 mm Length Rough Implants: A Case Series Report after an Average Loading Time of 33 Months

Aim. Several limiting factors encourage the clinician to use short implants. Among those, the presence of limiting anatomical elements and the simplification of surgical procedures are particularly significant. The goal of this study is to analyse the opportunity to extend the use of short implants to extrashort implants with a length less than 5 mm (ESI). Materials and Methods. Seven patients (3 women, 4 men; mean age 60.4 years) received extrashort implants (Straumann Implant, Palatal Orthosystem, length 4.2 mm, diameter 4.1 or 4.8 mm) in severe resorbed edentulous posterior areas. The implants were incorporated in partially fixed dentures. The osseous stability and the attachment level were recorded after a loading period of 22 to 54 months. Results. The results demonstrated a success rate of 100%, stability in the osseous level surrounding implants (mean annual mesial and distal loss of 0.026 mm and 0.105 mm, resp.), and no significant differences in the mean attachment depth between extrashort implants and contralateral teeth or implants (3.7 mm versus 3.55 mm, SD = 0.87). Splinting ESI with natural teeth resulted in significantly more bone resorption than with other implants (P=0.001). Conclusion. This exploratory study on the use of extrashort implants demonstrated good reliability over a loading period of 22 to 54 months.