Periodontitis is highly prevalent and develops from plaque-induced gingivitis. Managing gingivitis is key to preventing periodontitis and its complications. Professional mechanical plaque removal (PMPR) with oral hygiene guidance is effective for gingivitis, but large-scale implementation-especially in China-faces challenges such as workforce shortages. Meanwhile, patient compliance with daily oral hygiene remains poor. An optimal oral care regimen featuring an intelligent electric toothbrush (i-Brush) has shown promise in enhancing self-care adherence and efficiency. However, it remains unclear whether PMPR is still necessary when used in conjunction with this optimal oral care regimen. This study aims to verify whether the i-Brush-based regimen is non-inferior to the combination of PMPR and the regimen in improving gingival inflammation in gingivitis and stage I periodontitis.