title: MicroCT assessment of bone microarchitecture in implant sites reconstructed with autogenous and xenogenous grafts: a pilot study.
abstract: OBJECTIVE
  To assess bone microarchitecture in maxillary sites grafted with autogenous or xenogenous grafts as well as to demonstrate the usefulness of microCT in dental implant research.
  
  
  METHODS
  Samples (n = 12) consisting of titanium fixation screws covered by at least 0.5-1 mm of human bone were obtained from 17 sites grafted with autogenous or xenogenous materials and prepared for microCT scanning and conventional histology. Bone histomorphometric parameters were evaluated in three distinct regions (graft region, transitional region, and native bone region). Three-dimensional (3D) bone-to-implant contact (BIC) calculation was performed using microCT data. Histological sections were used to calculate two-dimensional (2D) BIC percentages, which were compared with values obtained from 2D microCT images.
  
  
  RESULTS
  Histomorphometric parameters varied according to the type of graft used, but sites reconstructed with autogenous bone showed higher mean values in general. In autograft samples, indices for parameters such as Tb.Th and Tb.Sp were significantly different when the native bone region was compared to the graft region. While a higher mean 3D BIC was found in the native bone region for both graft materials, significant BIC differences were absent when graft types were compared. The 2D BIC percentages obtained from histological and microCT images were similar.
  
  
  CONCLUSIONS
  Autografts outperformed the xenogenous material used in this study concerning the histomorphometric parameters assessed. While graft type did not seem to influence 3D BIC, the native bone region showed the highest BIC percentages when compared to the other regions in both graft groups. In addition, 2D BIC ratios were similar regardless of graft material or image source (histological sections x microCT slices). Taken together, our findings suggest that microCT is an effective tool for 2D and 3D histomorphometric and BIC assessments in dental implant research.
authors.affiliation: Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Karla
authors.initials: K
authors.lastname: de Faria Vasconcelos
authors.affiliation: Department of Prosthetic Dentistry, Oral Health Sciences, Faculty of Medicine, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Lívia
authors.initials: L
authors.lastname: Dos Santos Corpas
authors.affiliation: Department of Prosthetic Dentistry, Brazilian Dentistry Association (ABO-RJ), Rio de Janeiro, Brazil.
authors.forename: Bernardo Mattos
authors.initials: BM
authors.lastname: da Silveira
authors.affiliation: Bruker/Skyscan, Kontich, Belgium.
authors.forename: Kjell
authors.initials: K
authors.lastname: Laperre
authors.affiliation: Department of Implant Dentistry, Latin American Institute for Dental Research and Training (ILAPEO), Curitiba, Brazil.
authors.forename: Luis Eduardo
authors.initials: LE
authors.lastname: Padovan
authors.affiliation: OMFS Impath Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven, Leuven, Belgium.|Department of Maxillofacial Surgery, Leuven University Hospital, Leuven, Belgium.
authors.forename: Reinhilde
authors.initials: R
authors.lastname: Jacobs
authors.affiliation: Department of Dentistry, Federal University of Sergipe, Lagarto, Brazil.
authors.forename: Paulo Henrique Luiz
authors.initials: PH
authors.lastname: de Freitas
authors.affiliation: Biomedical Research Institute, Laboratory of Morphology, Hasselt University, Diepenbeek, Belgium.
authors.forename: Ivo
authors.initials: I
authors.lastname: Lambrichts
authors.affiliation: Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Frab Norberto
authors.initials: FN
authors.lastname: Bóscolo
mesh_terms: D000328:Adult; D000368:Aged; D016025:Bone Transplantation; D054893:Cone-Beam Computed Tomography; D005260:Female; D064593:Heterografts; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008437:Maxilla / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008875:Middle Aged; D010865:Pilot Projects; D014182:Transplantation, Autologous
keywords: 3D analysis; X-ray microtomography; bone grafting; bone substitute; diagnostic imaging