Dental maxillary practice model has the sinus along with tooth #8, 12 and 14 that are anatomically rooted and have the canals in place.
This allows you to practice endodontic procedures on the teeth and then see if the teeth were over filled. Below the teeth (on every tip) there is a silicone lesion.
The gum can be refracted and the surgery can be performed. The lesions can be removed and the gingiva can be sutured back into place
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