A scoring system for registration of apical periodontitis in radiographs is presented. The system is termed the periapical index (PAI) and provides an orditial scale of 5 scores ranging from 1 (healthy) to 5 (severe periodontitis with exacerbating features). Its validity is based on the use of leference radiographs of teeth with verified histological diagnoses. Results from studies involvirig 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 diflerent researchers to be compared. The syst(;iTi may be suitable for the analysis of periapieal radiographs in epidemiologieal studies, in clinical trials and in retrospective analyses of treatment results in endodonties.

The purpose of the study was to evaluate a possible relationship between the quality of the coronal restoration, the root canal obturation and the periapical status of endodontically treated teeth. Full mouth series of radiographs from randomly selected patient charts at the Dental Faculty, University of Oslo were examined. A total of 1001 endodontically treated teeth restored with a permanent restoration were evaluated independently by two examiners. According to a predetermined set of radiographic criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the technical quality of the coronal restoration was scored as good (GR) or poor (PR). The root and the surrounding structures were then evaluated and according to the periradicular findings, the treatment was categorized as success or failure. The success rate for all endodontically treated teeth was 67.4% (n = 1001). Teeth with root canal posts had a success rate of 70.7% (n = 527) and teeth without posts had a success rate of 63.6% (n = 472). The two groups with technically good endodontics had the highest success rates. In combination with technically good restorations the success rate was 81% (GE + GR, 81%) and combined with technically poor restorations the success rate was 71% (GE + PR, 71%). The two groups with technically poor endodontics combined with either good restorations or poor restorations had significantly lower success rates (PE + GR, 56% and PE + PR, 57%). The technical quality of the endodontic treatment as judged radiographically was significantly more important than the technical quality of the coronal restoration when the periapical status of endodontically treated teeth was evaluated.

The occurrence of Enterococcus faecalis in root canals of previously root filled teeth with apical periodontitis requiring retreatment was studied in Lithuanian patients. Twenty-five asymptomatic teeth were included in the study. Avoiding contamination microbiological samples were taken from the canals before and after preparation and irrigation with sodium hypochlorite and EDTA. Microbes were isolated from 20 of 25 teeth. E. faecalis was isolated from 14 of those 20 culture positive teeth, usually in pure culture or as a major component of the flora. Second samples taken after preparation revealed growth in 7 of the 20 teeth. Five of the seven cases were E. faecalis in pure culture. Isolation of E. faecalis was not related to the use of any particular root filling material in the original root filling. The results indicate that, rather than previous chemical treatment, it is the ecological conditions present in the incompletely filled root canal that are important for the presence of E. faecalis in these teeth.

treatment and prevalence of apical periodontitis in an adult population of Vilnius, Lithuania. Endod Dent Traumatol 1999; 15: 2 10-2 15. 0 Munksgaard, 1999. Abstract -Apical periodontitis is prevalent in many Western populations and is frequently detected in connection with inferior quality of endodontic treatment. However, information about endodontic conditions from eastern European countries is limited. The aim of the present investigation was to study the prevalence of apical periodontitis and the quality of endodontic treatment in 35-44-year-old Lithuanians. The prevalence of apical periodontitis was 70%. An overall success rate of 65% was found for root-filled teeth while 56% of pulp amputations (pulpotomies) were considered successful based on a radiographic evaluation. The quality of the root fillings showed little impact on the treatment results, except for over-extended fillings, which were associated with a high number of failures.