During the past 20 years, a plethora of research reports has been published showing a statistical association between poor oral health and cardiovascular diseases. The aim of this narrative review was to focus on associations between oral infections and non-atherosclerosis-related systemic diseases. An open literature search and evaluation of articles were conducted on Medline and Cochrane databases with the key words 'oral infection', 'periodontitis', 'pneumonia', 'osteoarthritis', 'rheumatic diseases', 'inflammatory bowel disease', 'kidney disease', 'liver diseases', 'metabolic syndrome', 'diabetes', 'cancer', 'Alzheimer's disease'. Cardiovascular diseases were excluded from the analysis. The scarcity of controlled studies did not allow conducting a systematic review with meta-analysis on the topics, but dental infections have been shown be associated with several general diseases also beyond the atherosclerosis paradigm. However, there is no causal evidence of the role of dental infections in this regard. Poor oral health has nevertheless often been observed to be associated with worsening of the diseases and may also affect treatments. Maintaining good oral health is imperative regarding many diseases, and its importance in the daily life of any patient group cannot be over emphasised.