A scoring system for registration of apical periodontitis in radiographs is presented. The system is termed the periapical index (PAI) and provides an ordinal scale of 5 scores ranging from 1 (healthy) to 5 (severe periodontitis with exacerbating features). Its validity is based on the use of reference radiographs of teeth with verified histological diagnoses. Results from studies involving 11 observers and 47 selected radiographs document that the PAI system is reasonably accurate, reproducible and able to discriminate between sub-populations. It may also allow for results from different researchers to be compared. The system may be suitable for the analysis of periapical radiographs in epidemiological studies, in clinical trials and in retrospective analyses of treatment results in endodontics.

The periapical index: A scoring system for radiographic assessment of apical periodontitis

Using a careful anaerobic bacteriological technique, bacteria were shown to be eliminated from infected root canals before the endodontic treatment was finished by root filling. Healing of the periapical lesions of the teeth was followed for 2–5 yr. The majority of the 79 lesions healed completely or decreased in size in such a way that they could be expected to heal. In 5 cases there was no or only an insignificant decrease in the size of the lesions. Two of these lesions were shown to contain bacteria of the species Actinomyces or Arachnid. In another case there were dentin chips in the periapical tissue. Periapical lesions which fail to heal in spite of careful bacteriological monitoring of the endodontic treatment may in some cases be due to an establishment of the bacteria outside the root canal in the periapical tissue. In these sites, the bacteria are inaccessible to conventional endodontic treatment.

Healing of periapical lesions of pulpless teeth after endodontic treatment with controlled asepsis.

Failure of endodontically treated teeth: classification and evaluation

Patel S, Dawood A, Wilson R, Horner K, Mannocci F. The detection and management of root resorption lesions using intraoral radiography and cone beam computed tomography ‐ an in vivo investigation. International Endodontic Journal, 42, 831‐838, 2009. Aim To compare the accuracy of intraoral periapical radiography with cone beam computed tomography (CBCT) for the detection and management of resorption lesions.

http://www.endoexperience.com/documents/Thedetectionandmanagementofrootresorption2009.pdf

The detection and management of root resorption lesions using intraoral radiography and cone beam computed tomography – an in vivo investigation

This retrospective study on the outcome of conventional root canal therapy was carried out on patients attending the Eastman Dental Hospital between 1970 and 1982. A minimum follow-up period of 5 years was required for patients to be included in the survey. The characteristics of the resulting sample group, the techniques for canal preparation and obturation and the obturating materials used were analysed. The type of obturating material used had no demonstrable effect on success rate but sex, age, preoperative vitality and periapical pathology were associated with significantly differing success rates. Technique also influenced success rate; the method of canal preparation and the position of the apical seal relative to the radiographic apex were both found to be significant. The overall success rate was 84.29%, representing 692 of 821 teeth included in the survey.

David A. Scott

Papers

Endodontic recall radiographs: How reliable is our interpretation of endodontic success or failure and what factors affect our reliability?