Use of fluoride has led to dramatic improvements in oral health; however, the impact of these improvements on the volume and mix of treatment provided in dental systems is largely unknown. The use of administrative data to analyze trends in treatment provision gives ‘real-life’ insight into the impact of changing levels of oral health on oral health services. The first aim of this study was to determine the extent to which useful data on temporal treatment patterns could be extracted from a public insurance database. The second aim, contingent on the first, was to investigate whether increased tooth retention and decreases in caries were reflected in the volume and types of treatment provided to adults within a public social insurance scheme between 1997 and 2008. Data were retrieved from the Dental Treatment Benefit Scheme databases, and new datasets were generated to analyze the distribution of treatments and mean treatments provided to 1,271,937 adults over the 12-year period. Provision of restorations, extractions, and dentures decreased, and the ratio of preventive/diagnostic to invasive treatments per dentist increased, which supports reported improvements in oral health. In conclusion, this paper illustrates the decline in invasive treatments, and increase in preventive treatments that accompanied improvements in oral health.