AbstractBackground: Despite the scarcity of studies regarding periodontal disease in young patients (teenagers and young adults), it seems that this disorder is also affecting the young population. Risk factors for periodontal disease include older age, chronic tobacco use, male gender, habits regarding oral hygiene, educational status, ethnicity, and financial status.Aim: This study aimed to evaluate the periodontal health among adolescents in two high schools in Târgu Mureș that had dental practices.Material and Methods: An online questionnaire consisting of 16 questions was distributed among high schoolers of Târgu Mureș. Data about personal characteristics, oral hygiene habits, family history of periodontal disease, risk factors for periodontal disease, and symptoms of periodontal disease observed by the respondents were collected and analyzed.Results: Out of the 501 teenagers who responded to the online questionnaire, 114 (22.8%) were 18 years old and were mostly females (88.2%). Regarding oral hygiene habits, 75.8% prefer a manual toothbrush over an electric toothbrush, 66.7% brush their teeth twice a day, and 54.1% practice a horizontal method of toothbrushing. Mouthwash was the most used oral hygiene aid (58.3%). Family history of periodontal disease was observed in 21.9% of respondents. As favoring factors, nicotine addiction (23.8%), bruxism (24.4%), interposition of various objects between teeth (48.3%), past or present orthodontic treatments (38.7%) were recorded. Symptoms of gingivitis and periodontitis, such as gingival bleeding (81.4%), redness of gingiva (39.3%), increased gingival volume (44.5%), gingival retraction (22.8%), and halitosis (81%), were present in the responding teenagers.Conclusions: In this study, periodontal disease was affecting mostly adolescent females who are practicing inappropriate methods of toothbrushing with inadequate frequency.