This study designed to assess amount of bone gain following composite graft rehabilitation of horizontal maxilla atrophy with sausage technique utilizing (pericardial) collagen membrane versus Periosteal membrane harvested from the iliac crest in 6 months.

Edentulous Maxillary ridges are a growing challenge worldwide. According to a fact sheet released by the World Health Organization (WHO) in 2022. teeth loss can be attributed to many conditions, mainly advanced dental caries, and severe periodontal disease. But pathology trauma and infection are other potential causes. Substantial studies have shown Dental implants as an excellent treatment choice with predictable long-term results.

However, to guarantee the success of implant stability at the time of insertion, a sufficient amount of bone width is robust. As known that bone surrounding extracted teeth resorb in all directions. This leads to horizontal and vertical bone volume loss reaching up to 50% in width reduction which compromises dental implant insertion. Cawood and Howell in 1988 categorized the degrees of edentulous ridge atrophy into six categories, emphasizing category IV atrophies which are known as "knife-edge" ridge, present a serious horizontal defect, making dental implant placement a challenge.

The challenge of bone defects augmentation primarily lies in the insufficient bone volume at the implant site, which can negatively impact the success of dental implants. Severe horizontal bone defects, such as those classified as "knife-edge" ridges, present significant obstacles for effective implant placement. Sausage Technique: Specifically designed for cases with severely thin ridges, this technique utilizes a collagen membrane stabilized with titanium pins to secure the bone graft. This helps prevent the migration or collapse of graft particles, promoting better bone gain and healing. Still some limitation of this technique including possibility of the collagen membrane becoming exposed during the healing process, which can compromise the regenerative outcome. Limited Bone Gain: In some cases, the amount of bone gain achieved may not meet the expectations, particularly in severely atrophic ridges, which can lead to the need for additional augmentation procedures. A study by Fernando V, et al showed that recipient sites augmented with autogenous bone grafts and preserved periosteal membranes maintained an average bucco-lingual width of 8.1 mm after augmentation, which was significantly greater than the baseline width of 3.2 mm. This augmented width was maintained at 98% after an average follow-up of 2.9 years. Another study by Kubota and Shirasuna evaluates the effectiveness of free periosteum in secondary bone grafting for maxillary alveolar clefts.

Results indicate that 97.1% of patients receiving free periosteum achieved significant vertical bone formation, compared to 79.5% in the control group. While the free-periosteum group experienced a higher rate of postoperative wound dehiscence. The rationale of the study is to evaluate the effectiveness of a combination of autogenous bone and an organic bovine bone-derived mineral (ABBM) for horizontal ridge augmentation using sausage technique utilizing (pericardial) collagen membrane versus Periosteal membrane harvested from the iliac crest. The study aimed to Assess bone gain in insufficient maxillary alveolar ridge width, particularly in patients with knife-edge ridges, to facilitate successful dental implant placement.

Inclusion Criteria:

• Age range (18-60 years)
• Patients with unilateral or bilateral horizontal atrophy in maxilla with minimum 1 quadrant.
• No intervention done previously on the donor and host sides.
• No sex predilection

Exclusion Criteria:

• Syndromic patients.
• bone metabolism & systemic diseases.