Long-term survival of cast-gold inlays in a specialized dental practice

At a dental office in Münster, Germany, the majority of gold inlays incorporated between July 1969 and August 1999 (n=2,071) in 531 patients were checked with reference to the dental records and assessed retrospectively to determine their longevity. One hundred seventy-five gold inlays were rated as failures (no longer in situ); 10 abutment teeth were extracted. The 20-year Kaplan-Meier survival rate for restoration-bearing teeth was 98.9%, and the 25-year rate for all gold inlays 73.4% (+/- 4.0%; 95% confidence interval respectively in brackets). Gold inlays inserted in maxillary teeth had significantly better probabilities of survival after this period than those inserted in lower teeth (P=0.0002). Based on the number of surfaces involved, 52.0% (+/- 45.3) of one-surface inlays, 64.3 (+/- 7.5) of two-surface inlays, 75.8% (+/- 7.6) of three-surface inlays, and 84.8% (+/- 5.4) of inlays with more than three surfaces were still in situ after 25 years.