title: The detection of periapical pathosis using digital periapical radiography and cone beam computed tomography - part 2: a 1-year post-treatment follow-up.
abstract: OBJECTIVE
  Part 2 of this clinical study aims to compare the radiographic change in periapical status of individual roots determined using digital periapical radiographs versus cone beam computed tomography (CBCT) 1year after primary root canal treatment and to determine the radiological outcome of treatment for each tooth.
  
  
  METHODS
  Periapical radiographs and CBCT scans of 123 teeth in 99 patients assessed 1year after completion of primary root canal treatment by a single operator were compared with their respective pre-treatment (diagnostic) periapical radiographs and CBCT scans. The presence or absence as well as the increase or decrease in size of existing periapical radiolucency was assessed by a consensus panel consisting of two calibrated examiners. The panel viewed the images under standardized conditions. Paired comparison of the outcome diagnosis of individual roots and teeth was performed using generalized McNemar's or Stuart-Maxwell test of symmetry analysis.
  
  
  RESULTS
  The 'healed' rate (absence of periapical radiolucency) for all roots combined was 92.7% using periapical radiographs and 73.9% for CBCT (P<0.001). This rate increased to 97.2% and 89.4%, respectively, when the 'healing' group (reduced size of periapical radiolucency) was included (P<0.001). A statistically significant difference in outcome diagnosis of single roots was observed between DPA and CBCT in single-rooted teeth and the buccal or mesio-buccal roots of multi-rooted teeth (P<0.05). Analysis by tooth revealed that the 'healed' rate (absence of periapical radiolucency) was 87% using periapical radiographs and 62.5% using CBCT (P<0.001). This increased to 95.1% and 84.7%, respectively, when the 'healing' group (reduced size of periapical radiolucency) was included (P<0.002). Outcome diagnosis of teeth showed a statistically significant difference between systems (P<0.001). Reconstructed CBCT images revealed more failures (17.6%) in teeth with no pre-operative periapical radiolucencies compared with periapical radiographs (1.3%) (P=0.031). In teeth with existing pre-operative periapical radiolucencies, reconstructed CBCT images also showed more failures (13.9%) compared with periapical radiographs (10.4%).
  
  
  CONCLUSIONS
  Diagnosis using CBCT revealed a lower healed and healing rate for primary root canal treatment than periapical radiographs, particularly in roots of molars. There was a 14 times increase in failure rate when teeth with no pre-operative periapical radiolucencies were assessed with CBCT compared with periapical radiographs at 1year.
authors: Department of Conservative Dentistry, King's College London Dental Institute, London, UK. shanonpatel@gmail.com
authors: S
authors: S
authors: Patel
authors: R
authors: R
authors: Wilson
authors: A
authors: A
authors: Dawood
authors: F
authors: F
authors: Foschi
authors: F
authors: F
authors: Mannocci
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001641:Bicuspid / Q000000981:diagnostic imaging; D002648:Child; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003481:Cuspid / Q000000981:diagnostic imaging; D005260:Female; D005500:Follow-Up Studies; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D007180:Incisor / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D008963:Molar / Q000000981:diagnostic imaging; D015588:Observer Variation; D010483:Periapical Diseases / Q000000981:diagnostic imaging* / Q000628:therapy; D011176:Post and Core Technique; D016300:Radiography, Bitewing / Q000379:methods*; D019252:Radiography, Dental, Digital / Q000379:methods; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods; D012390:Root Canal Therapy; D014092:Tooth Root / Q000000981:diagnostic imaging; D016896:Treatment Outcome; D014945:Wound Healing / Q000502:physiology; D055815:Young Adult
chemical_list: D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D006171:Gutta-Percha