Two cases: 1. If the workbench does not automatically identify the contact between teeth, the contact identification tolerance can be changed to be greater than 0.3mm；; 2. If the above method still fails to meet the requirements, add contact pairs manually instead. This way is more flexible. As for the contact type, it needs to be determined according to your simulation needs. Bonded is obviously not used in the contact type of the workbench. According to whether the friction between teeth is considered or not, one of three ways can be selected: no friction, complete friction and specified friction coefficient.