The aim of this paper was to study, through a clinical case report, the behavior of deproteinized bovine bone (Bio-Oss) covered with a resorbable barrier membrane (Bio-Gide) when used as an onlay grafting material to obtain alveolar bone ridge enlargement. The presence of an existing bone edge allowed placement of an MK III groovy implant and creation of the required space for ridge enlargement, using xenograft particles (Bio-Oss) covered with a resorbable barrier membrane (Bio-Gide), during the same surgical stage. Recording of anatomical landmarks in the three dimensions of space in relation to implant position allowed precise assessment of the graft behavior during the tomodensitometric examinations performed at 6 and 18 months postsurgery. A biopsy was performed at 9 months postsurgery for histologic and histomorphometric analyses. The tomodensitometric images allowed observation of the preservation of the grafted bone volume. The histologic analysis revealed vital bone formation with the remaining Bio-Oss particles; the histomorphometric analysis, at this stage, provided similar percentages of Bio-Oss (27.94%) and newly formed bone (24.07%). This clinical example confirms the biocompatible and osseoconductive properties of Bio-Oss, as well as stability of the bone graft volume. These different elements testify to the advantage of its use for alveolar ridge enlargement.