Rationale: In this case study, a modified transcrestal approach was applied to the patient of extremely atrophic posterior maxilla. We analysis the Implant Stability Quotient values (ISQ) to monitor implant stability, and the cone-beam computer tomography (CBCT) to evaluate the bone regeneration.
Patient concern: A 26-year-old female patient visited our hospital with no contraindications for dental implants and a loss of the maxillary right first molar.
Diagnose: Examination by CBCT demonstrated the posterior maxilla was extremely atrophic, the residual bone height (RBH) of #16 was 3.5 mm.
Intervention: Patient underwent a endoscopically controlled flapless sinus floor elevation. The maxillary sinus membrane was elevated by two-step, and an implant of 12 mm length was placed simultaneously.
Outcomes: Twelve weeks post-surgery, the implant-level impression was finished and a full-ceramic crown was placed thereafter.
Lessons: The modified transcrestal approach can be applied to augment maxillary sinus with a residual bone height less than 4 mm.