Root Canal Irrigants and Medicaments in Endodontic Malpractice Cases: A Nationwide Longitudinal Observation.

Introduction: The aim of this study was to assess the role of root canal irrigants and medicaments in endodontic injuries verified in Finland and to estimate the rate of such events over time.

Methods: The study material comprised all endodontic injuries verified by the Patient Insurance Centre in 2002 to 2006 (n = 521) and 2011 to 2013 (n = 449). The data, based on patient documents scrutinized by 2 specialists in endodontics, included patients' and dentists' sex and age and the service sector. We recorded the use of root canal irrigants and medicaments, each as a dichotomy. Furthermore, we dichotomized the injuries as those related to root canal irrigants/medicaments and any other injuries. The injuries were also dichotomized as avoidable (could have been avoided by following good clinical practice) or unavoidable (normal treatment-related risks). Statistical evaluation used chi-square tests and t tests; logistic regression produced odds ratios (ORs).

Results: The verified injuries (N = 970) comprised 635 (65%) avoidable and 335 (35%) unavoidable injuries. The number of irrigant-/medicament-related injuries was 69, accounting for 7.1% of all verified injuries; all resulted from sodium hypochlorite and calcium hydroxide, and 87% were avoidable. The overall rate of sodium hypochlorite/calcium hydroxide injuries was 4.3 cases per 100,000 endodontic patients per year. Compared with other injuries, sodium hypochlorite/calcium hydroxide injuries were more likely avoidable (OR = 3.8) and more than 5-fold likely in 2011 to 2013 than in 2002 to 2006 (OR = 5.6).

Conclusions: Extreme care is needed when applying sodium hypochlorite and calcium hydroxide into root canals to avoid increasing harmful consequences.