The ultimate guide to restoration longevity in England and Wales. Part 5: crowns: time to next intervention and to extraction of the restored tooth

摘要

Aim It is the aim of this paper to present data on the survival of crowns in all teeth by analysis of the time to re-intervention on the crowns and time to extraction of the crowned tooth, and to discuss the factors which may influence this. Results Data for more than three million different patients and more than 25 million courses of treatment were included in the analysis. Included were all records for adults (aged 18 or over at date of acceptance). Overall, 1,202,005 crowns were included, of which 302,555 had a re-intervention over the duration of the dataset. Overall, 52% of crowns have survived at 15 years, with factors influencing survival being patient age, dentist age and patient treatment need. However, when the data are re-analysed with regard to time to extraction, while crowns provide a patient with a restoration which requires the least number of re-interventions, they perform poorly when time to extraction is examined. The placement of a pinned core appears to enhance the longevity of the subsequent crown, whereas the placement of a root filling or a metal post does not. With regard to tooth position, crowns placed on upper canine teeth perform worse than crowns placed on any other tooth, while crowns perform best on first molar teeth. Conclusions Crowns may provide a patient with a restoration which requires the least number of re-interventions. However, they perform poorly when time to extraction is examined.