title: Effect of Root Filling on Stress Distribution in Premolars with Endodontic-Periodontal Lesion: A Finite Elemental Analysis Study.
abstract: BACKGROUND
  Endodontic-periodontal (EP) lesions require both endodontic and periodontal therapies. Impermeable sealing of the root canal system after cleaning and shaping is essential for a successful endodontic treatment. However, complete healing of the hard and soft tissue lesions takes time, and diseased bone, periodontal ligament, and tooth fibrous joints are reported to have an increased failure risk for a given load. Considering that EP lesions may affect the biomechanics of teeth, this finite elemental analysis study aimed to test the effect of root fillings on stress distribution in premolars with EP lesions.
  
  
  METHODS
  Three finite elemental analysis models representing 3 different types of EP lesions (primary endodontic disease [PED], PED with secondary periodontic involvement, and true combined) were created. The root canals were assumed as nonfilled or filled with gutta-percha, gutta-percha/apical mineral trioxide aggregate (MTA) plug, and MTA-based sealer. Materials used were assumed to be homogenous and isotropic. A 300-N load was applied from the buccal cusp of the crown with a 135° angle. The Cosmoworks structural-analysis program (SolidWorks Corp, Waltham, MA) was used for analysis. Results were presented considering von Mises criteria.
  
  
  RESULTS
  Stresses at the root apex increased with an increase in lesion dimensions. Root filling did not affect stress distribution in the PED model. An MTA plug or MTA-based sealer created more stress areas within the root compared with the others in the models representing PED with periodontic involvement and true combined lesions.
  
  
  CONCLUSIONS
  Stresses at the apical end of the root increase with increases in lesion dimensions. MTA-based sealers or an MTA plug creates more stresses when there is periodontic involvement or a true combined lesion.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Selcuk University, Konya, Turkey. Electronic address: sbelli@selcuk.edu.tr.
authors.forename: Sema
authors.initials: S
authors.lastname: Belli
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Selcuk University, Konya, Turkey.
authors.forename: Oğuz
authors.initials: O
authors.lastname: Eraslan
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Yuzuncuyil University, Van, Turkey; Gazi University, Ankara, Turkey.
authors.forename: Gürcan
authors.initials: G
authors.lastname: Eskitascioglu
mesh_terms: D017607:Aluminum Compounds / Q000009:adverse effects; D001641:Bicuspid / Q000503:physiopathology*; D017610:Calcium Compounds / Q000009:adverse effects; D004338:Drug Combinations; D020342:Finite Element Analysis; D006171:Gutta-Percha / Q000009:adverse effects; D006801:Humans; D010087:Oxides / Q000009:adverse effects; D010510:Periodontal Diseases / Q000503:physiopathology*; D012387:Root Canal Filling Materials / Q000009:adverse effects*; D017640:Silicates / Q000009:adverse effects; D013314:Stress, Mechanical; D019227:Tooth Apex / Q000503:physiopathology*
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; D006171:Gutta-Percha
keywords: Apical plug; FEA; combined endodontic-periodontal lesion; periapical bone lesions; periapical status; root filling; stress distribution