title: Estimation of radiographic angles and distances in coronal part of mandibular molars: A study of panoramic radiographs using EMAGO software.
abstract: OBJECTIVE
  This study was designed to investigate radiographically the effects of age and external irritating stimuli on the morphology and thickness of the pulp chamber ceiling and floor in mandibular molars.
  
  
  METHODS
  A total of 234 panoramic radiographs were recruited and 494 mandibular molars were examined in this study. The sample was divided into six age groups: Group 1, <20 years; Group 2, 20-29 years; Group 3, 30-39 years; Group 4, 40-49 years; Group 5, 50-59 years and Group 6, >60 years. Each group was subdivided into two subgroups with regard to the tooth condition (intact or non-intact teeth). Four distances, two angles and two ratios were measured, in order to estimate the dimensions of the pulp chamber and the thickness of the pulp chamber ceiling and floor.
  
  
  RESULTS
  The thickness of the pulp chamber ceiling and floor increased significantly from Group 1 to 6. The pulp chamber floor angle presented progressive sharpness from Group 1 to 6 whereas the pulp chamber ceiling angle presented progressive bluntness from Group 1 to 5 and sharpness from Group 5 to 6. Significant differences were identified in the thickness of the pulp chamber ceiling, the thickness of the pulp chamber floor and the ceiling-floor distance between intact and non-intact teeth.
  
  
  CONCLUSIONS
  Based on those results, there are differences in the location of secondary dentin formation between the two pulp chamber walls. Age is related to diminished pulp chamber size. The increase rate of the pulp chamber ceiling thickness is similar to that of the pulp chamber floor thickness. Furthermore, external irritating stimuli have an effect on the pulp chamber dimensional changes.
authors: Department of Endodontics, School of Dentistry, University of Athens, Athens, Greece.
authors: Ioannis N
authors: IN
authors: Tsatsoulis
authors: Department of Endodontics, School of Dentistry, University of Athens, Athens, Greece.
authors: Christos G
authors: CG
authors: Filippatos
authors: Department of Endodontics, School of Dentistry, University of Athens, Athens, Greece.
authors: Spyros G
authors: SG
authors: Floratos
authors: Department of Endodontics, School of Dentistry, University of Athens, Athens, Greece.
authors: Evangelos G
authors: EG
authors: Kontakiotis
keywords: Angles; EMAGO; molars; panoramic radiographs