Objective: To investigate oral health changes and its associated factors during hospitalization in individuals with acquired brain injury (ABI).Material and Methods: Sixty-one individuals were recruited to evaluate the acute changes in oral health by performing plaque, calculus, bleeding on probing (BOP) and bedside oral examination (BOE) at week 1 and week 5. Individuals’ brushing habits, eating difficulties, onset of pneumonia etc. were retrieved from e-journal. Association between oral-health outcomes to systemic variables were investigated through multilevel regression models.Results: Dental plaque (P=0.01) and total BOE score (P<0.05) decreased over time but not the calculus (P=0.30), BOP (P=0.06) and increase in tooth brushing frequency (P=0.06). Reduction in plaque, and BOE over time were negatively associated with higher score of periodontitis at baseline (coef. -6.8; -1.0, respectively), which in turn were associated with an increased proportion of BOP (coef. ≈ 15.0). Increased proportion of calculus was associated with eating difficulties (coef. 2.3) and onset of pneumonia (coef. 6.2).Conclusions: Nursing care has been fundamental in improving oral health but non-significant improvement in calculus, BOP and brushing frequency indicates a need for development in existing oral care program through academic-clinical partnership keeping eating difficulties and patients’ vegetative and cognitive state in consideration.