Dr. Salazar Kagan

Dr. Salazar Kagan is a professional oral surgeon and a dentist. In the books, he is referred to as Dr. Kagan. He is a rather new antagonist in the series, making his debut in The Ugly Truth.

Greg has a crush on his dentist. Then one day, Greg's father takes him to his dentist because he was growing up. Dr. Kagan is a sadistic dentist who decorates his waiting room with posters of teeth, and a poster that has a crossed-out picture of a soda can, telling how soda is harmful for peoples' teeth. He is Frank Heffley's dentist, and at the middle of a appointment with Greg Heffley he gets his finger bitten when he is taking x-rays with Greg's molars. As a result of his anger from his bit finger or according to the x-rays, he gives Greg headgear, which later on was stolen by Manny Heffley.