<p>There are numerous factors that can impact both the correction of jaw deficiencies and the success of a particular grafting material, including the histology and density of both the maxillary and mandibular bones and the grafting material itself. This study compares the clinical outcomes of grafted augmentations of the horizontal alveolar ridge of the anterior maxilla using mandibular symphysis onlay bone that was admixed with either injectable platelet-rich fibrin (i-PRF) or xenografts. Twelve adult patients with horizontal maxillary alveolar ridge deficiency were randomly divided into two groups of six patients each. Group I received mandibular symphysis onlay bone grafts mixed with i-PRF, while Group II received mandibular symphysis onlay bone grafts admixed with xenografts (InterOss anorganic cancellous granules). CBCT scans were used to measure alveolar ridge width and bone density both preoperatively and at 6-month follow-up. Both groups showed improvements in alveolar ridge width and bone density. The increase in measured bone width and density after 6 months in Group II was significantly greater than that in Group I (<i>p</i> = 0.040). Horizontal alveolar ridge augmentation using an onlay chin graft in combination with xenografts was successful and offered adequate bone quantity and quality.</p>