POST-OPERATIVE PAIN: AN ANALYSIS ON EVOLUTION OF RESEARCH IN HALF-CENTURY

Abstract

Every year, millions of teeth around the world are saved by root canal treatments. According to an American Dental Association survey, approximately 15.1 million patients received root canal treatments in the United States (1). Pain after root canal treatment is a major health problem affecting the quality of life in the short-term and sometimes also in the long-term. Root canal treatment is generally very effective in alleviating tooth pain (2, 3). However, recent prospective studies indicate that severe pain can occur in approximately 20% of patients during the week following root canal treatment (4). In other words, one out of every five patients who receive root treatment will experience a major disruption in their daily life due to this unwanted postoperative outcome. Further, up to 10% of patients may suffer from persistent pain 6 months after endodontic treatment (5). Overall, these numbers show that millions of patients in the United States and, by inference, around the world deal with severe pain in the days following root canal treatment, and many develop persistent pain. Post-operative pain can significantly affect quality of life (6) and lead to serious economic consequences. This includes the impact on the patients’ daily performance (physical and emotional impacts of pain) (7), and increases spending by patients, insurance companies, and governments on medications and additional dental/medical visits. As researchers understand the mechanisms and predictors of pain after root canal treatment, they find more relevant ideas about how to address this health problem. In addition, technologic advances in treatment and research methods can encourage new research. Therefore, the variables of interest in research studies change over time. Also, researchers revise the methodologies adopted for investigations as they learn more about evidence-based medicine The aim of this study was to analyze the evolution of study design and research variables in the field of post-operative pain over the past 50 years.