title: Human tooth and root canal morphology reconstruction using magnetic resonance imaging.
abstract: OBJECTIVE
  Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes.
  
  
  METHODS
  The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume.
  
  
  RESULTS
  The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered.
  
  
  CONCLUSIONS
  Magnetic resonance imaging offers 3D image datasets with more information than the conventional radiographic techniques. Due to its ability of imaging both hard and soft dental tissues, magnetic resonance imaging can be successfully used as a 3D diagnostic imaging technique in dentistry. When choosing the imaging method, dental clinicians should weight the benefit-risk ratio, taking into account the costs associated to magnetic resonance imaging and the harmful effects of ionizing radiations when cone beam computed tomography or conventional x-ray are used.
authors.affiliation: Faculty of Dental Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Oana Carmen
authors.initials: OC
authors.lastname: Drăgan
authors.affiliation: Faculty of Physics, Babes-Bolyai University, Cluj-Napoca, Romania.
authors.forename: Alexandru Ştefan
authors.initials: AŞ
authors.lastname: Fărcăşanu
authors.affiliation: Faculty of Dental Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Radu Septimiu
authors.initials: RS
authors.lastname: Câmpian
authors.affiliation: Faculty of Physics, Babes-Bolyai University, Cluj-Napoca, Romania.
authors.forename: Romulus Valeriu Flaviu
authors.initials: RV
authors.lastname: Turcu
keywords: magnetic resonance imaging; radiographic image enhancement; radiography; root canal; tooth morphology