Vertical Ridge Augmentation Using Deproteinized Bovine Bone Material Without Covering With a Membrane: A Tunnel Pouch Technique—4-Year Follow-up—A Pilot Clinical Study

The present pilot clinical trial was planned to evaluate the effect of particulate deproteinized bovine bone graft mixed with blood used as a vertical ridge augmentation material without covering with any form of collagen membrane in a tunnel pouch technique, resulting in sufficient bone formation to allow placement of dental implants with maintenance of the newly formed bone after final restoration. Eight patients (3 males and 5 females) were selected for this procedure and treated between February 2016 and December 2017. All these patients had a deficient vertical height of the posterior mandibular alveolar bone above the inferior alveolar canal. The particulate deproteinized organic bovine bone graft (Bio-Oss) mixed with blood was placed through the tunnel in the defected area and compacted firmly to form a dense pack. The average gain of alveolar bone in the first implant site immediately postoperative was 13.51 ± 0.85 and in the second implant site was 13.84 ± 0.62. Histomorphometric analysis showed that about 70.31% of the area analyzed was occupied by the vital bone, the newly formed bone, whereas only 29.69% of the residual graft remained. In the present pilot study, the deproteinized bovine bone graft placed to enhance vertical and horizontal bone gain showed positive results in regaining the bone needed to place implants and maintaining the bone around restored implants for 4 years of follow-up.