Objective: The purpose of the study to assess the relationship between oral health and the general health of individuals especially tooth loss and the systemic illness. Materials and Methods: A retrospective study of 804 digital orthopantomograms (OPGS) taken of patients, age ranging between 20 and 70 years, who presented to treatment at the Regional Dental Center, AL-Qassim, Saudi Arabia between 2018 and 2019. The OPGS and dental records were reviewed for missing teeth among patients with systemic illness. Results: We found a high prevalence of tooth loss in hypertension (10.63), DM (9.62), hypothyroidism (6.79) and Asthma (6.35). Conclusion: This study reported a high prevalence of tooth loss among the patients with systemic illness rather than the patients with no systemic illness. The presence of more than one illness and older age patients showed a high prevalence of tooth loss. These findings clarify the importance of the effect of the systemic health on the oral health.