The digital transformation of healthcare and Ministry of Health Regulation No. 24 of 2022 require even small dental clinics to migrate from paper-based administration to electronic medical records (EMR). Bertha Desnalia Dental Clinic previously managed patient registration, medical records, queues, drug inventory, and billing manually, which caused data redundancy, slow retrieval of patient history, and error-prone manual billing. This study designs and implements a web-based EMR, named Dental, whose scientific contribution is not merely the co-location of administrative modules but the embedding of billing and drug-inventory logic directly inside the medical-record transaction, so that clinical documentation and financial settlement are produced from one consistent data model. The system was developed with the Waterfall model (requirements analysis, design, implementation, testing, deployment) using PHP (CodeIgniter) and MySQL, and it was modelled with UML use-case and class diagrams before implementation. Verification was limited to functional black-box testing of six modules (authentication, patient registration, queue, medical record, drug management, and billing) at a single clinic, and all predefined test scenarios, including negative and boundary cases, produced the expected outputs. The system is therefore designed to shorten patient-data retrieval and to reduce manual calculation errors in billing rather than demonstrated to do so, because no comparative timing or error-rate measurements were collected. The remaining limitations, treated as directions for further work, are that access control is enforced only as menu-level differentiation rather than complete server-side role-based access control, and that drug stock is not yet deducted automatically per transaction.