Observational 13-year study of posterior tooth fracture in dental practice

Objective: to present posterior tooth fracture (PTF) data collected over 13 years in dental practice. Method: A classification was used that has been reported before; Class l enamel only, Class ll enamel and dentine, Class lll enamel and dentine coronal to the amelo-gingival junction and Class lV as in Class lll but below the attached gingivae. Primary PTF is a newly recorded fracture and a secondary PTF is one that restores a previously repaired PTF. Primary and secondary PTF and its restoration was recorded in 5273 patients. One skilled operator undertook all procedures. Result: the average age of the patients was 49 years and 52% were female. Total restorations placed were 77566 and of these 5273 (7%, Confidence Intervals [CI] = 4.3-8.2%) were PTF restorations. The proportion of PTF restorations were Class I=2% (CI=0.3-2.2%), II=32% (CI=31.9-40.3%), III=64% (CI=61.6-70.3%) and IV 3% (CI= 1.8-5.7%). Primary PTF were 43% (CI=39.7-48.4%) and the remainder were secondary PTF. Eighty three per cent of the PTF teeth had 2 to 3 surface restorations in situ (CI = 80.4 to 84.9%). The PTFs were restored with glass ionomer (81%, CI=76.3-83.3%), composite (17%, CI 11.2-17.4%), cast crowns (3%, CI=1.8-4.9%) and amalgam (2%, CI=1.0-3.7%). Conclusion: posterior tooth fracture is a reason for restorations in the molar and premolar region in the mature dentition. Compared with previous data from the same subject cohort, the most significant change was the decrease in PTFs from 33% to 7% over 13 years. The proportion of glass ionomer and composite restorations has increased whilst amalgam has decreased