Although the mandibular molar region is the area where dental implant therapy is performed most frequently, the width of the bone is narrow in many cases. The aim of this case report is to newly introduce the lateral ridge augmentation procedure using a modified lateral incision technique.

Guided bone regeneration combined with autologous bone graft for bone augmentation was performed on implant placement at the mandibular left molar area of a 55-year-old woman. Because the position of the mental foramen was comparatively high, a modified lateral incision technique designed to prevent neuronal damage was used. Buccal split-thickness incision was performed 4 mm below the mucogingival junction and was extended through the mesial aspect of the aftermost molar. The split-thickness incision was then extended with a vertical split-thickness incision at the location of the mesial line angle of the aftermost molar. Following supraperiosteal preparation, the periosteum was cut at the height of the alveolar crest. The full-thickness incision line was designed to leave the periosteum distal area of the aftermost molar of approximately 2 mm. The flaps of both split-thickness and full-thickness were then separated. Following perforation of the cortical bone to create the bleeding bone surface, two implants were placed into the planned positions. After autologous bone graft was performed, nonresorbable expanded polytetrafluoroethylene titanium-reinforced membrane was adjusted to the surgical site. Horizontal mattress sutures were used between the keratinized mucosa of the lingual flap and the periosteum of the buccal flap, and intermittent sutures were used between the mucosa of the lingual flap and the mucosa of the buccal flap, without excessive pressure and while ensuring closure of the membrane. At the time of the secondary operation, free gingival grafting was performed to increase the width of the keratinized tissue. Four years after surgery, the postoperative outcome is good.

Lateral ridge augmentation with the modified lateral incision technique may be a safe method of implant placement with bone graft in cases where the mental foramen is located at a higher position than usual.