Background <p>Early childhood caries remains a major global public health concern. As parents and children increasingly rely on digital platforms for health information, the quality and reliability of online educational resources become critical. Despite the abundance of general oral health content, studies specifically evaluating child-oriented toothbrushing instructions remain scarce. To address this gap, the present study evaluated and compared the quality, reliability, and guideline adherence of child-oriented toothbrushing videos in Turkish and English, highlighting potential disparities between global and localized digital health information ecosystems.</p> Methods <p>A cross-sectional analysis of YouTube videos was conducted using predefined Turkish and English keywords. After applying exclusion criteria (e.g., entertainment-only and non-instructional videos), 51 videos (27 Turkish, 24 English) were included. Two independent reviewers assessed videos using the Global Quality Scale (GQS), DISCERN, and a 10-item guideline-based content compliance checklist. Engagement metrics (views, likes, viewing rate, and interaction index) were recorded, and associations between engagement and evaluation scores were examined.</p> Results <p>English-language videos showed higher median GQS and DISCERN scores than Turkish-language videos (3.25 vs. 1.50, <i>p</i> = 0.042; and 3.00 vs. 2.00, <i>p</i> = 0.037, respectively). Guideline-based compliance scores were also higher in English videos (5.50 vs. 3.00, <i>p</i> = 0.018). Videos uploaded by animation channels demonstrated significantly lower quality and compliance scores compared with educational and health-related channels (<i>p</i> &lt; 0.001). No significant correlations were observed between engagement metrics and GQS, DISCERN, or compliance scores (all <i>p</i> &gt; 0.05).</p> Conclusion <p>The overall quality, reliability, and guideline adherence of child-oriented toothbrushing videos were limited, and Turkish-language content demonstrated lower evaluation scores than English-language content. The lack of association between engagement and evaluation scores indicates that popularity does not reflect informational quality, underscoring the need for greater involvement of dental professionals in producing evidence-based, age-appropriate digital educational materials. Actionable strategies, such as clinician-guided video recommendations and the future development of digital quality-labeling systems, may help guide families toward more reliable content.</p>