The increasing popularity of dental implants has led to an increase in the number of late implant failures. Although the failure of dental implants is rare, it produces a challenging clinical situation. Thus, the scope of causes that is detrimental to dental implants and peri-implant tissues is important to be explored. Inadequate forces resulting from occlusion may cause complications that leading to implant failure. It is found that the mechanical-related contributing factors (biomechanical overloading) significantly affect the implant persistence as compared to the biological factors. The present review, therefore, emphasises the causes of the overloaded dental implants and technical complications in clinical scenarios. A comprehensive search was performed via ScienceDirect, Scopus and PubMed databases using the related keywords. The literature indicates various factors could trigger biomechanical overloading and promote the occurrence of implant failures: parafunctional habits, implant diameter, length, thread shape and material and implant-abutment connection. The relationship between these factors and implant longevity is still controversial, with further randomised clinical trials and advanced quantitative assessments are required to help elucidate this issue.
