This paper was aimed to review the studies published about short dental implants. In the focus were the works that investigated the effect of biting forces of the rate of marginal bone resorption around short implants and their survival rates. Bone deformation defined by strain was obviously higher around short implants than the conventional ones. The clinical outcomes of 6 mm short implants after 2 years showed a survival rate of 94% to 95% and lower survival rate (<80%) for 7？mm short implants after 3 to 6 years for single crown restorations. The short implants used for supporting fixed partial prostheses had a survival rate of 98.9%. Short implants can be considered as a good alternative implant therapy to support single crown or partial fixed restorations. 1. Introduction After tooth loss, severely atrophic residual alveolar ridges are fairly common, especially in patients who have been edentulous for a long period of time. The bone volume of posterior areas of the maxilla and the mandible is frequently insufficient for the placement of implants with adequate dimensions, unless a procedure such as ridge augmentation or sinus floor elevation is performed. Although widely utilised, these techniques imply greater morbidity, longer treatment times, and higher costs. The sinus cavity in the maxilla and alveolar nerve proximity in the mandible are clinical situations where short implants could be considered as an alternative treatment option. Some have hesitated to use these implants due to the perception of a higher risk of failure compared with longer implants for both fixed restorations [1–5], as well as maxillary overdentures [6, 7]. More recent studies, however, suggested that short implants (7 to <10？mm) can reach similar success rates as longer ones for the support of fixed partial dental prostheses [8–10]. Even 3-year [11] and 7-year [12] followup studies reported retrospectively that short implants (8 to 9？mm long) [9, 13, 14] were not less successful compared with implants >10？mm long in the posterior region with fixed partial dental prostheses. This paper was aimed to review the works regarding the stability and survival rate of short implants under functional loads. Numerical and clinical studies were reviewed. 2. Implant Fatigue under Biting Forces Prospective studies have shown the positive effect of conventional implant therapy on maximum bite force [15–19]. However, alveolar bone (similar to long bones) adapts its strength to the applied mechanical loading by means of bone modelling/remodelling [20–22]. The response to increased mechanical
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