Endodontology - Root canal treatment and root-filled teeth

Root canal treatment in general dental care

Studies on indications, costs and results
Despite the fact that dental health in Sweden has improved, root canal treatments are a common measure in general dental care. Statistics from the Swedish Social Insurance Agency show that in 2010, 250,000 new root fillings were registered. Root canal treatment, which involves a mechanical and chemical disinfection of a tooth's root canals, is often technically complicated, time consuming and is often experienced as difficult by general dentists. Root canal treatments have been evaluated in terms of tooth survival and maintenance or establishment of healthy periradicular conditions. Follow-ups have primarily been performed at universities and specialist clinics. Dental survival is generally high and has been estimated at 85–90% over a 10-year period. Optimally performed root canal treatments result in healthy periradicular tissues in 85–95% of cases. However, in epidemiological studies, signs of infection and inflammation in root-filled teeth are common. In Scandinavian populations, the frequency varies between 25–50%.

Prospective cohort studies of root canal treatments performed in general dental care are almost completely lacking and the need for such has been pointed out by both the Swedish Agency for Medical Evaluation (SBU) and the National Board of Health and Welfare. In addition, the importance of clinical research for root canal treatment prevention has been emphasized.

The overall goal of this prospective cohort study carried out in collaboration with Folktandvården in Västra Götaland is to generate better knowledge about root canal treatment in Swedish public dental care and in particular to estimate the costs, evaluate the benefits and examine the outcome of root canal treatments performed in general practice.

Can chronic asymptomatic apical periodontitis of root-filled teeth be left untreated and can clinical risk factors for an emergency be identified?

There are approximately 10 million root-filled teeth in Sweden alone, of which 25% have signs of persistent infection and inflammation, apical periodontitis. In most cases, the condition is chronic and asymptomatic. But it happens that the inflamed area in the jaw enlarges or that the patient suddenly develops swelling and pain. There is great variation and disagreement about how a symptom-free root-filled tooth with apical periodontitis should be treated. The National Board of Health and Welfare's national guidelines for adult dental care assess the condition to have a moderate effect on oral health and give the condition a relatively low priority (6 on a scale 1-10). From an academic point of view, it has been more or less an axiom that these teeth should be treated. In specialist clinics for endodontics, treatment of root-filled teeth occupies approximately 50% of the clinical time. Treatment is associated with costs in the order of 5000-20000 kronor. The patients who have subjective problems from their root-filled tooth obviously need to have the condition cured or remedied. For those who are asymptomatic, however, the necessity of treatment is questioned.

The purpose of this project is to systematically and prospectively investigate whether asymptomatic root-filled teeth with signs of apical periodontitis can be left without action without significant risk of symptoms or deterioration (increasing part of the surrounding tissues involved) and to identify risk factors for such adverse events. The results can possibly lead to that the number of time-consuming and costly root canal retreatments or tooth extractions can be reduced.