BACKGROUND: This in-vitro study aimed to evaluate the temperature development on root surfaces of mature single rooted teeth during guided endodontics preparations performed in a continuous and intermittent mode, and during conventional post preparation. METHODS: Sixty extracted human teeth were divided into three groups and cut horizontally at the level of the cementoenamel junction. In 40 specimens, mechanical preparation was performed with a defined continuous maximum force of 10N in a universal testing machine: 20 were prepared using a guided endodontics bur (Group CGE) and 20 using a post-preparation bur (Group CPP). The remaining 20 specimens were prepared at low force using the guided endodontics bur in intermittent steps of 2-3mm with intermediate irrigation (Group IGE) until the defined depth of 7mm was reached. Temperature change on the root surface was recorded using two temperature probes attached to the buccal and proximal root surface. For all three groups, preparations were performed in a water bath at 37°C to simulate oral conditions. RESULTS: A significant higher temperature change was observed in group CGE, especially on the proximal surface (mean 42.5°C; 95% CI 39.1 - 46.0), compared to group CPP proximal (mean 37.7°C; 95% CI 37.5 - 37.9; p < 0.05). Temperature change in group IGE proximal (mean 38.5°C; 95% CI 37.8 - 39.1) was similar to group CPP. CONCLUSIONS: When performing static guided endodontics, intermittent preparation including irrigation avoids harming temperature changes on the root surface and leads to a heat development similar to conventional post preparation.
Bernauer et al. (Mon,) studied this question.