The injectable composite resin technique is an indirect/direct method that uses a transparent silicone index for accurate and predictable translation of a diagnostic wax-up into composite restorations without the need for tooth preparation. This case report involves a 22-year-old man who presented with esthetic and functional problems associated with diastemas and insufficient tooth visibility. Clinical examination revealed inadequate canine guidance in lateral excursion. The treatment plan included the fabrication of composite veneers for the maxillary incisors and canines. A wax-up was prepared by simulation of functional movements on an articulator, and a transparent silicone index was prepared after checking a mock-up in the oral cavity. The teeth were restored with flowable composite injected and polymerized through the transparent silicone index. The conventional technique was modified by cutting the silicone index at the gingival margin, using individual mock-ups as space holders, and the use of gingival retraction cords. The final outcomes were elongated teeth for increased visibility, closed diastemas, and reshaped canines for adequate guidance in lateral excursion. A protective splint for night-time wear was fabricated and delivered to ensure long-term stability. The patient did not exhibit any soft tissue inflammation or significant wear during a 24-month follow-up period. The technique described is minimally invasive and inexpensive, and it can be used for definitive as well as translational restorations. The treatment goals are to establish adequate function and esthetics, with advantages including minimal tooth structure loss and cost-effectiveness. Stable and predictable results can be achieved with proper planning and a careful workflow. Palabras clave: composite resin injection, composite veneer, esthetic rehabilitation, functional rehabilitation, transparent silicone index