Background: Periodontal disease (PD) is a chronic inflammatory condition characterized by destruction of supporting structures of the teeth. Intelligence quotient (IQ) was potentially reported to significantly associated with prevalence of gingivitis. Mild gingivitis was obtained in high IQ levels while moderate gingivitis may be attributed to poor oral hygiene seen among the subjects having low IQ levels. Method: One hundred volunteers aged between 20-45 years old were enrolled in this study, patients were equally divided into right- and left-handed (50 patients each)and each group then subdivided into patients with healthy gingiva(10), patients with gingivitis (20), and patients suffering from periodontitis (20).An IQ questionnaire was prepared to be answered by each patient, Periodontal health status was recorded by using clinical periodontal parameters, plaque index (PLI)and gingival index (GI). Results: Analysis of data showed that there is no significant difference in parameters measured in the same group. Results of IQ score among healthy, gingivitis and periodontitis groups indicated presence of significant difference (P≤0.001) between right- and left-handed as compare to healthy subjects, Furthermore, in left-handed patients, IQ score was significantly higher (P≤0.05) in gingivitis group in comparison to periodontitis patients. In contrast, same groups in right-handed patients showed almost the same IQ score. The same pattern was observed in association with plaque index. Conclusion: Left-handed individuals have higher potential in providing plaque control. However, IQ score did not affect oral hygiene level with increased severity of periodontal disease in both groups.
