Institutionalized children, regardless of their age, are prone to psychiatric disorders, compared to those who live in two-parent families, due to the unfavorable physical and psychological conditions in which they develop. Unpropitious psychological conditions affect the child’s general health and induce local manifestations that can be found in the oral cavity, affecting both soft tissues and teeth. Therefore, the purpose of our study was to assess and diagnose a series of pathological manifestations of the oral mucosa associated with poor living conditions or closely related to psychological stress. The clinical examination was performed by 4 specialist dentists, who consulted 150 children representing the study group and 52 children representing the control group, all having ages between 14 and 18 years old and meeting the same inclusion criteria. From the control group, 62.5% presented plaque-induced gingivitis (26.6% girls, 35.8% boys), 26.6% presented mucosal lesions produced by lip and cheek biting (23.3% girls, 35.8% boys), and 11.7% presented geographic tongue (6.6% girls, 5% boys), herpes simplex eruptions (3.3% girls, 4.2% boys) and oral ulcerations (12.5% girls, 10.8% boys). Morsicatio buccarul is a chronic, self-mutilating habit, currently becoming one of the most common tics encountered among institutionalized children. Furthermore, these children do not benefit from constant support and guidance to perform their dental hygiene, so the incidence of gingivitis induced by bacterial plaque and calculus is very high.