UNASSIGNED: The purpose of the present study was to investigate the survival rate of root filled teeth in general dentistry in a Swedish county and to identify risk predictors with a significant influence on the survival rate.
UNASSIGNED: This is a retrospective 6-year follow-up study on 1642 recall patients with 1720 teeth root filled in general dentistry in the Public Dental Service in the county of Stockholm, Sweden. Background variables were collected from the database at baseline as potential predictors of tooth loss. The outcome variables were extraction during the 6-year follow-up period and the reason for the extraction. Stepwise Cox regression analysis was adopted in order to investigate the influence of the potential risk predictors on the risk for tooth extraction.
UNASSIGNED: Nine percent of the root filled teeth were lost after 6 years. The most frequent reason for tooth loss was fracture and/or cracks (58%). The survival rate of the root filled teeth increased significantly for younger patients, root filled teeth with metal crowns (96%) and high quality of the root filling (93%). The survival rate differed significantly between tooth groups with the lowest survival for molars (83%). Composite fillings were significantly associated with lower quality of the root fillings.
UNASSIGNED: Ninety-one percent of the root filled teeth survived after 6 years. The survival rate was significantly higher for teeth with root-fillings of high quality and metal crowns as well as for root filled teeth in younger patients. The lowest survival rate was found for molars.

OBJECTIVE: First, to examine the impact of the residual volume of coronal tooth structure in posterior teeth measured with an intra-oral scanner on the 4-year clinical survival of root canal retreated teeth. Secondly, to assess retrospectively the effectiveness of the Dental Practicality Index (DPI) in predicting the survival of root canal retreated teeth.
METHODS: A total of 156 posterior root canal treated teeth (140 patients) had baseline periapical radiographs (PA) and cone-beam computed tomography (CBCT) scans taken prior to root canal retreatment. These teeth were followed up with a clinical examination at 1, 2, 3 and 4 years (T12, T24, T36 and T48) with periapical radiographs and CBCT images taken at T12, and PA taken at T24, T36 and T48 where appropriate. Root canal retreated teeth were dichotomized into \'survived\' versus \'extracted\'. Fisher\'s exact test was used to determine the association between the volume of remaining coronal tooth structure and the 4-year tooth survival. The Dental Practicality Index for each tooth was established using the preoperative clinical and radiographical data. Fisher\'s exact test was used to establish a relationship between categorical variables, the total score of DPI vs tooth outcome.
RESULTS: The percentage of extractions associated with teeth with <29.5% remaining coronal tooth structure was 3 times higher (12.5%) compared to that of teeth with a residual tooth structure > 29.5% (3.5%), but with no significant difference (P = 0.073). There was a significant correlation between the outcome of root canal retreatments at 1 year, assessed by both PA and CBCT, and the 4-year survival (Fisher\'s exact test, P = 0.007 and P = 0.001, respectively). Teeth with DPI scores ≥ 6 were more likely to be extracted than teeth with DPI score < 6 (18.8% vs. 3.9%) (Fisher\'s exact test, P = 0.045).
CONCLUSIONS: Teeth with <30% of remaining tooth structure were associated with a survival rate above 80% and teeth with more than 30% of residual tooth structure survived in more than 94% of the cases. The radiographic outcome of root canal treatment can also help to predict tooth survival with teeth having an unfavourable outcome at 1 year more likely to be extracted within 4 years of completion of treatment. The DPI score can potentially be used to identify teeth with failed root canal treatment, which are likely to be extracted following retreatment and cuspal coverage.

BACKGROUND: There are few data on the long-term efficacy of mineral trioxide aggregate (MTA) in treating root canal perforations. We investigated the extent of primary healing after perforation repair with MTA and non-healing as a result of repair. We also investigated patient/clinical characteristics affecting treatment outcomes and long-term prognosis.
METHODS: This was a prospective cohort study that enrolled consecutive patients with a single dental perforation treated with MTA (January 1999-June 2009). Patients were followed up until December 2012 for a maximum of 13 years after treatment, with analyses carried out at 8 years.
RESULTS: Of the 110 patients (median age, 36 years; 54.5% male) eligible for inclusion, 101 were judged to have started to heal at the first (n = 98, 89%) or second (n = 3, 3%) annual post-treatment checkup, and 9 (8%, 4 women and 5 men, aged between 18 and 65 years) did not show any sign of healing. Patients >50 years had a higher percentage of non-healing perforations compared with those ≤ 50 years (12% versus 7%). The percentages of perforations at post-treatment analysis that failed to heal were 13% (intermediate/middle), 4% (coronal), and 0% (apical). The percentages of non-healing perforations according to size were 16% for >3 mm, 6% for 2-3 mm, and 0% for smaller perforations. Characteristics associated with probability of progressing after initial healing were gender, positive probing, size, and site of perforation.
CONCLUSIONS: Our results show that having obtained primary healing with MTA, the likelihood of progressing is very low. They provide good evidence of the combined effectiveness of experienced operators and use of state-of-the-art materials.

OBJECTIVE: Data showed that among 5-year-old Chinese, 96.7% of cavitated primary teeth were left untreated. The study aimed to report on the course of cavitated primary teeth within the Chinese health-care system over a period of 3.5 years.
METHODS: Selection of high caries risk children for inclusion in a sealant comparison study was based on the presence of cavitated dentine lesions in their primary teeth. At the 6-month sealant evaluation point many of these cavitated dentine lesions had not been treated. This necessitated monitoring these cavitated teeth 6-monthly for those exfoliated, restored, with a cavity left open, having caused toothache (symptom) and having (or having had) an abscess or fistulae (symptom). Care-seeking instruction was given at every evaluation point. anova and t-test were used in analysing the data.
RESULTS: A total of 1012 cavitated primary teeth in 305 children (7.6 to 9.3 years old), were followed for 3.5 years. A total of 92.9% of cavitated primary teeth were left open, while 7.1% were restored at some stage during the observation period; 98.5% of restored teeth and 95.5% of cavitated teeth left open exfoliated and 93.9% of restored teeth and 81.5% of cavitated primary teeth left open exfoliated without any symptoms. Having (or having had) toothache was the symptom most frequently related to exfoliated restored teeth and to exfoliated cavitated teeth left open. Restored primary teeth survived statistically significantly longer than cavitated primary teeth left open: 1.99 ± 0.07 years and 1.68 ± 0.03 years, respectively.
CONCLUSIONS: The large majority of cavitated primary teeth in this child population exfoliated without symptoms.