A patient presented with the chief complaint of deep bite and malaligned teeth despite having undergone orthodontic treatment during childhood. Clinical examination and treatment history revealed that the mandibular right and left first premolars, maxillary right first premolar, and maxillary left canine had been extracted during the previous orthodontic treatment.

A comprehensive orthodontic evaluation, including lateral cephalometric analysis, revealed a skeletal Class II relationship with retrognathic maxilla and retrognathic mandible. The treatment objectives included correction of the deep bite, alignment of the dentition, and reopening of the mandibular first premolar spaces for future implant rehabilitation. The mandibular first premolars had been extracted during the previous orthodontic treatment despite not being indicated for extraction, resulting in the need for space regaining and dental implant placement.

Orthodontic treatment was carried out using Invisalign aligners to align the teeth, improve the occlusion, and regain adequate space in the mandibular first premolar regions. Following space opening, severe bilateral ridge deficiency was noted at the edentulous sites, with ridge widths of approximately 2–2.5 mm.

Due to the extremely narrow mandibular ridge, conventional ridge splitting procedure was considered unfavorable. A modified ridge augmentation procedure was performed involving buccal vertical corticotomy cuts followed by gradual expansion using piezoelectric surgery and hand instruments. Guided bone regeneration (GBR) was then carried out at both sites, and the areas were allowed to heal for approximately 8–9 months.

After ridge maturation, Nobel Biocare implant placement was performed using a CAD/CAM-guided flapless surgical approach. Healing abutments were placed, followed by a healing period of approximately 4 months. Definitive implant-supported zirconia crowns were subsequently delivered in the mandibular first premolar regions.