The present study reports a case of a periapical lesion in an implant placed in an alveolar ridge which presented a residual root fragment of a deciduous tooth. Patient attended a dental clinic because she wanted to replace the missing tooth with an implant. She reported having lost the temporary tooth for one year. The initial Cone-beam Computerised Tomography image showed an edentulous area in the #13 zone, and the presence of a fragment of the deciduous tooth. The small root fragment was removed and an implant 4.0 × 13 mm amplified was installed. Patient presented acute pain and inflammation at the implant site 20 d after the surgery when the implant was originally installed; the first periapical surgery was carried out. Four months after the first periapical surgery, in periapical x-ray a radiolucent lesion was observed surrounding the apical region of the implant with a dry sound under percussion. The second periapical surgery was carried out. Five months after the second periapical surgery, the presence of a fistula was observed clinically, while in X-ray a radiolucent lesion was observed in the apex of the implant. Implant-plasty was carried out, removing approximately 5 mm of the apical portion of the implant. This treatment was successful after 27 months' monitoring.