Root canal morphology of 116 maxillary second premolars by micro-CT in a mixed Swiss-German population with systematic review

Abstract Introduction The aim of this investigation was to examine the root canal system morphology of maxillary second premolars (Mx2Ps) of a Swiss-German population by means of micro-CT and to systematic revise the root canal configuration (RCC) literature of Mx2Ps. Methods The RCC, main foramina as well as accessory canals and foramina frequency of 116 Mx2Ps were investigated by means of micro-computed tomography and 3D-software imaging. The RCC from the coronal to apical thirds of the root as well as the main foramina number were described using a four-digit system code. The literature review follows the PRISMA guideline analyzing randomized controlled trials and cross-sectional, cohort, comparative, validation and evaluation studies on RCC in Embase, grey literature, Pubmed and Scopus. Results Mx2Ps mostly frequently RCC’s observed were 1-1-1/1 (35.3%), 1-1-1/2 (21.6%) and 2-1-1/1 (14.7%). Another 11 less frequently RCC’s were observed. All Mx2Ps were had one root. One main foramen was observed in 59.5% and two in 37.9%. Accessory foramina were observed in 46.6%. 31.0% of the Mx2Ps showed accessory canals. One connecting canal between the buccal and palatal was observed in 12.1%. Conclusions Detailed RCC information of Mx2Ps in a Swiss-German population and the results of a systematic literature review of different populations and research methods used to investigate root canal morphology and configuration of Mx2Ps are given. Within the limitations of the study, a high RCC, connecting and accessory canals variability occur in maxillary second premolars.