Background: The aims of this study are to present sociodemographic and familial characteristics, clinical and systemic findings, dental treatment needs, and concomitant dental anomalies in patients with amelogenesis imperfecta (AI) and to evaluate time-varying conditions in these long-term follow-up patients. Materials and Methods: Records of patients with AI who were examined in the Department of Pediatric Dentistry between 1999 and 2017 were reviewed. Information about sociodemographic characteristics, history of AI and consanguinity in family, systemic conditions, reasons for referral to the clinic, oral hygiene habits and gingival health, occlusion findings, and performed treatments were gathered. Dental anomalies in radiographs were also evaluated. Baseline and final situations of the patients were assessed. Statistical analyses were performed. Results: Of 75 patients aged 3u15 years with follow-ups up to 12 years, 34 had AI in their families and 15 were born from consanguineous marriages. Nephrocalcinosis has been observed in 5 patients. Main reasons for referral to the clinic were related to esthetic and hypersensitivity concerns. Twenty-two patients had gingivitis, and during follow-up process, gingival problems could not be completely prevented due to poor oral hygiene habits. Vertical dimension loss, open-bite, and cross-bite were seen in 16, 15, and 10 patients, respectively. Of the patients, 63% experienced restorative, 33% stainless steel crown, 17% endodontic, 8% prosthetic treatments, and 24% had retreatment needs. Concomitant dental anomalies were dens invaginatus, taurodontism, ectopic eruption, delayed eruption, hypodontia, and pulpal calcification. Conclusion: Early diagnosis and interventions considering the time-varying conditions with long-term follow-ups provide significant improvements in clinical maintenance of patients with AI.