International Journal of Clinical Case Reports 2016, Vol.6, No.20, 1-7
5
longer implants. After a 12-months' follow-up, success rate reached 95.2% for shorter implants and an equal
success rate for long implants without statistically significant differences (p=0.78). The results showed short
dental implants to be equally effective as standard implants (Gentile et al., 2005). Barboza E et al assessed the
clinical performance of short dental implants (220, 9mm length; 128, 10mm length with diameter of 3.5, 4, or 5
mm), during a 6-year follow-up study. Success rate reached 96% (334 implants). The results obtained proved that
short dental implants could be used safely for supporting prosthesis in the rehabilitation of lost teeth displaying
success and longevity rates similar to longer implants (Barboza et al., 2007). MalóP et al found short dental
implants placed into atrophic mandibles provided results similar to the longer implants placed into higher bone
volumes (Malóet al., 2007). According to Misch, implant diameter is more important than height (Misch, 1999).
An increase in surface area is more dependent upon implant diameter than length once maximum length has been
determined as early bone loss and complications relate mainly to crestal bone regions since horizontal and vertical
occlusal forces placed on implants are supposed to be distributed primarily in the crestal bone rather than along
the entire implant/bone interface as demonstrated by Finite Elemental Analysis (FEA). Reduced alveolar bone
height can limit the use of implants. More dense bone can accommodate a shorter implant while in less dense
bone, a longer implant is more favorable. However, some risk factors, such as increased crown height and higher
bite forces, might increase stress when using short dental implants. To improve the biomechanical situation in
such cases, it is necessary to find methods that reduce forces on the implants. Eliminating or minimizing the
lateral force on the prosthesis and force distribution from splinting multiple implants plays a significant role in
reducing stress on implants (Misch et al., 2006). Anitua E et al conducted a study on 1287 implants less than
8.5mm in length placed in 661 patients in a 7-year follow-up study finding a 99.3% implant survival rate with a
mean follow-up period of 47.9 months and concluding that short dental implants were safe and predictable
(Anitua and Orive, 2010). Another study published by Koo KT et al in 2010 reported a cumulative
one-to-five-year survival rate of 95.1% with no statistically significant difference between maxillary and
mandibular placement for one or two-stage implants and short or longer implants (Koo et al., 2010). Telleman G
et al evaluated the estimated implant survival rates of short (<10 mm) dental implants placed in partially
edentulous patients through a systematic review of the literature and analyzed a total of 2611 short implants (5-9.5
mm in length). they concluded a fair evidence that short (less than10 mm) dental implants could be placed
successfully in partially edentulous patients although with a tendency towards an increasing survival rate per unit
of implant length (Telleman et al., 2011). Karthikeyan I et al systematically evaluated the publications published
between 1991 and 2011 in relation to short dental implants (≤7 mm length) placed in the maxilla and mandible
and included 28 studies representing one randomized controlled trial, 12 prospective and 10 retrospective studies
and concluded that the survival rate of short dental implants increased gradually from 80% to 90% with recent
studies showing upto 100% success rates (Karthikeyan et al., 2012).
3 Conclusion
Implant design and properties and the surface condition of implants might modify the percentage of bone-implant
contact which in turn implies, greater the percentage of bone contact, lesser the stress, applied to the bone-implant
interface. Over the period of time, implant designs has undergone lot of changes and implant surface texture has
also changed from smooth machined surface to rough acid etched, sand blasted and plasma sprayed surface. These
changes might be considered responsible for the increased success rates of short dental implants observed in the
recent studies. The short dental implants used in this case report had rough, acid-etched surface that showed
significantly greater bone-implant contact compared to machined or polished surfaces.
References
Arlin M.L., 2006, Short dental implants as a treatment option: Results from an observational study in a single private practice. Int J Oral Maxillofac Implants,
21: 769-776
Anitua E., Orive G., 2010, Short implants in maxillae and mandibles: A retrospective study with 1 to 8 years of follow-up. J Periodontol81:819-826
Bahat O., 1993, Treatment planning and placement of implants in the posterior maxillae: Report of 732 consecutive Nobelpharma implants, Int. J. Oral
Maxillofac Implants, 8: 151-161
