Replacing missing teeth in the posterior regions of the maxilla and mandible with limited alveolar bone is a clinical challenge. Short implants (≤6 mm) offer an alternative to regenerative procedures. The aim of this study was to conduct a systematic review of the literature regarding the clinical effectiveness, survival, marginal bone loss (MBL), risk factors, and complications associated with the use of short dental implants. The review was conducted using the MEDLINE/PubMed, Embase, Cochrane Central Register of Controlled Trials, and Google Scholar databases from their inception to August 2025. Studies involving implants ≤6 mm in length were analyzed. Short implants are characterized by high, predictable survival rates of 95–100% over 1–5 years. Key factors for success include appropriate macro- and micro-implant geometry, bone quality, careful prosthetic planning, and maintaining good oral hygiene. Marginal bone loss (MBL) around short implants is minimal, and complications are rare. Short implants (≤6 mm) are an effective, minimally invasive, and relatively economical method for replacing teeth in the posterior regions of the maxilla and mandible. Their use avoids the risks and burden associated with bone augmentation.