Objective: To study the relation between cracked teeth with different cusp inclination and maximum resistance strength.
Materials and Methods: Seventy maxillary premolars were randomly divided into four groups. Groups 1, 2 and 3 were made into models of cracked teeth with different buccal and palate cusp, respectively, while group 4 was the control group (untreated). Compression testing for the four groups was carried out using an electronic universal testing machine. The maximum resistance strength when the teeth cracked was recorded.
Results: Differences of the average maximum resistance strength of each group were statistically significant (P<0.05). Resistance strength decreased as cusp inclination increased. However, when cusp inclination increased to a specific level, there was no obvious decline.
Conclusions: The maximum resistance strength of different cusp inclinations is different, which decreases as cusp inclination increases.