Outcomes of Ridge Splitting Versus Sausage Technique

Several bone augmentation approaches address horizontal bone resorption to achieve successful implantation including bone block grafting, guided bone regeneration (GBR), sinus augmentation and alveolar ridge split , However, bone block grafting had disadvantages like donor site morbidity and longer treatment time,GBR had the risk of infection due to exposure membrane and collapse of the regeneration membrane (1)These drawbacks may eventually lead to implant failure Alternatively, the Alveolar ridge splitting technique may solve some barriers and create proper dimensions for delayed or immediate implantation in both maxillary and mandible.(2) The alveolar ridge splitting technique was introduced by Simion in 1992 as a successful bone grafting technique to augment the horizontally deficient alveolar ridge with immediate implant placement. (3)The main disadvantage of the conventional ridge splitting technique is the high risk of bad split, fractures or even fenestrations of the buccal cortical plate of bone during separation with massive crestal bone loss surrounding the implants.(4)Therefore, a lot of clinical trials were introduced using minimally invasive protocols dealing with such complications for example, the usage of piezoelectric surgery or using surgical guides.(5)

In the past, onlay grafts of bone harvested from the hip, maxillary tuberosity, symphysis of the chin, or external oblique ridge have all been used with success in reconstruction of atrophic ridges,onlay grafts often require a healing period of 6 months to a year before dental implants can be placed, and the onlay graft sometimes fails to fuse to the augmented site. (6)The segmental ridge-split procedure provides a quicker method where in an atrophic ridge can be predictably expanded and grafted with bone allograft, eliminating the need for a second surgical site.(7) Using of piezoelectric alveolar ridge splitting (ARS) with simultaneous implant placement will enhance implant stability in comparison with conventional motorized surgical disc and bur .(8) Piezosurgery enhanced implant stability but didn,t mitigate the bone loss associated with ARS or increase amount of ridge width gain.(9)

The piezosurgery can be a safer option in maintaining the vitality of bone and piezoelectric implant site drilling protocol seemed to be a reliable and repeatable technique. (10) Preparation of the implant bed with the aid of piezoelectric inserts showed improved implant stability with a 100% success rate .(11) Extensive alveolar bone augmentation using sausage technique achieved significant horizontal or vertical bone height or width increase, and the retention rate after 6 months was also high,In addition, surgery in the maxillary region showed a more successful bone augmentation than in the mandible, with a higher maintenance rate. (12)The concept of GBR uses graft materials as a scaffold to preserve the created space and a non-resorbable or resorbable membrane to exclude the growth of epithelium and connective tissue cells inward the defect. (13) Urban and colleagues proposed an improved technique to stabilize the graft material to the crest by modifying the collagen membrane fixation method and the original sausage technique combines autograft chips with an organic bovine bone mineral (ABBM) particles to provide the graft mixture with osteogenic properties.(14) Briefly, the technique is similar to conventional GBR in that the membrane is fixed with pins, However, the graft material is filled inside the fixed membrane in a sufficient quantity to show a balloon effect and to push the graft material in the crestal direction to create tension on the membrane ,In this technique, two types of collagen membranes can be used: a crosslinked synthetic collagen membrane or a native collagen membrane.(15)

Inclusion criteria

• Patients with deficient bone volume between (2 : 3.5 ) mm
• Patients must have installed functional implant for no less than 3 months- enough time to allow for bone augmentation changes.
• Patients with no defect in the gingival tissues.
• Patients with un-remarkable medical compromising conditions
• Patients with good oral hygiene at time of the examination

Exclusion criteria

• Patients with compromising medical condition.
• Patients with severe bone resorption.
• Patients with D1 or D2 bone.
• Bone height <10mm