ADO is a bone regeneration technique, introduced by Chin and Toth in 1996 based in a biological process used for regenerate and consolidate bone between two bone segments obtained after osteotomy.These segments have been gradually separated by the process of distraction. ADO can be performed both horizontally (AHDO) and vertically (AVDO).

Distraction osteogenesis (DO) can be used to regenerate missing hard and soft tissue, Distraction osteogenesis relies on the body's ability to generate bone as two segments of bone are "distracted" apart. The osteotomies are created and the distraction device is placed. Typically, there is a latency phase of one week were a fibrovascular bridge is formed in the osteotomy site. This provides a template to generate new bone as the segments are distracted apart during the activation phase. Once the desired distraction has occurred, the device is left in place for a period of time. Once consolidation (typically 2 to 6 months) has occurred, the distraction device can be removed and implants can be placed. Chiapasco compared GBR to DO and found that both are equally effective in alveolar bone augmentation for implant placement and further stated that the long-term prognosis of vertical bone gain in DO is more predictable.

Inclusion Criteria:

• Acquired alveolar defects (Post extraction, Traumatic avulsion of teeth, Periodontal disease, After tumor resection), congenital alveolar defects, vertically deficient edentulous ridge in maxillary or mandibular anterior region with
• Allen Type A moderate vertical ridge deficiency (3-6mm)

Exclusion Criteria

• Medically compromised patients
• Subjects who underwent radiotherapy or chemotherapy
• Smokers and
• Radiographic presence of less than 5mm of anterior maxillary and mandibular bone height