Horizontal Resorption of Fresh-Frozen Corticocancellous Bone Blocks in the Reconstruction of the Atrophic Maxilla at 5 Months Eugénio Pereira, DDM;* Ana Messias, MSc; † Ricardo Dias, DDM; ‡ Fernando Judas, PhD; § Alexander Salvoni, PhD; ¶ Fernando Guerra, PhD** ABSTRACT Background: Reliable implant-supported rehabilitation of an alveolar ridge needs sufficient volume of bone. In order to achieve a prosthetic-driven positioning, bone graft techniques may be required. Purpose: This prospective cohort study aims to clinically evaluate the amount of resorption of corticocancellous fresh- frozen allografts bone blocks used in the reconstruction of the severe atrophic maxilla. Materials and Methods: Twenty-two partial and totally edentulous patients underwent bone augmentation procedures with fresh-frozen allogenous blocks from the iliac crest under local anesthesia. Implants were inserted into the grafted sites after a healing period of 5 months. Final fixed prosthesis was delivered 1 4 months later. Ridge width analysis and measurements were performed with a caliper before and after grafting and at implant insertion. Bone biopsies were performed in 16 patients. Results: A total of 98 onlay block allografts were used in 22 patients with an initial mean alveolar ridge width of 3.41 1 1.36 mm. Early exposure of blocks was observed in four situations and one of these completely resorbed. Mean horizontal bone gain was 3.63 1 1.28 mm (p < .01). Mean buccal bone resorption between allograph placement and the reopening stage was 0.49 1 0.54 mm, meaning approximately 7.1% (95% confidence interval: [5.6%, 8.6%]) of total ridge width loss during the integration period. One hundred thirty dental implants were placed with good primary stability (3 30 Ncm). Four implants presented early failure before the prosthetic delivery (96.7% implant survival). All patients were successfully rehabilitated. Histomorphometric analysis revealed 20.9 1 5.8% of vital bone in close contact to the remaining grafted bone. A positive strong correlation (adjusted R 2 = 0.44, p = .003) was found between healing time and vital bone percentage. Conclusions: Augmentation procedures performed using fresh-frozen allografts from the iliac crest are a suitable alternative in the reconstruction of the atrophic maxilla with low resorption rate at 5 months, allowing proper stability of dental implants followed by fixed prosthetic rehabilitation. KEY WORDS: allografts, alveolar ridge augmentation, corticocancellous block, fresh-frozen bone, iliac crest INTRODUCTION Bone augmentation techniques are widely used for the reconstruction of severely atrophic jaws prior to dental implants placement. The lack of appropriate volume of bone is caused by trauma, oncologic diseases, oral infec- tions, congenitally missing teeth, or by the alveolar ridge tridimensional resorption process subsequent to dental *PhD Student, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; † Assistant Lecturer, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; ‡ Assistant Lecturer, Faculty of Medi- cine, University of Coimbra, Coimbra, Portugal; § Assistant Professor, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; ¶ Invited Professor, Faculty of Odontology and Medicine, São Leopoldo Mandic, Campinas, Brazil; **Associate Professor, Faculty of Medicine, University of Coimbra, Coimbra, Portugal Corresponding Author: Dr. Eugénio Pereira, Área de Medicina Dentária da Faculdade de Medicina da Universidade de Coimbra, Avenida Bissaya Barreto, Blocos de Celas – HUC, 3030 075 Coimbra, Portugal; e-mail: genocawahoo@gmail.com Conflict of Interest and Source of Funding Statement: The authors declare that they have no conflict of interests related to this study. Implant materials were provided by Conexão, Sistemas de Prótese, Brazil. Fresh-frozen allografts were provided from the Bone and Tissue Bank of the Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. © 2014 Wiley Periodicals, Inc. DOI 10.1111/cid.12268 1