Background: Dental pattern diversity was investigated in different populations, but none have focused on Saudi Arabia. Aim: The aim of this study was to investigate the dental pattern diversity in Saudi Arabia. Setting and Design: This was a retrospective study. Materials and Methods: Five thousand two hundred and twenty-five orthopantomograms of healthy dentate adults were divided into four age groups: Group 1, 18–30 years; Group 2, 31–45 years; Group 3, 46–55 years; and Group 4, >55 years. The conditions of the 32 teeth in each individual were assigned to 10 characteristics to form a dental pattern, and the diversity of patterns was estimated using the Simpson's Diversity Index. Statistical Analysis: The diversity, proportions, and frequency of unique dental patterns were descriptively compared between age groups and sexes. Results: The dental pattern diversity for full dentition was >0.99, with 5024 unique dental patterns. The diversity and frequency of dental patterns were lower in the maxillary and mandibular anterior segments compared to those in posterior segments. All virgin teeth were the most frequently observed dental pattern for full dentition (1.24%). The dental pattern diversity for full dentition was similar across the age groups, but the frequency of unique dental patterns was 68.23%, 91.47%, 90.39%, and 88.89% for Groups 1, 2, 3, and 4, respectively. Further, the frequency of unique dental patterns was 10%–20% higher in females than in males. Conclusions: The dental pattern diversity was high in the studied Saudi Arabian sample and was affected by individuals' age and sex, where older individuals and females have higher diversity than younger individuals and males.