title: Peri-implant soft tissue analyses comparing Ti and ZrO2abutments: an animal study on beagle dogs.
abstract: OBJECTIVE
  The aim of this study was to evaluate the soft tissue histomorphometric composition around implant abutments comparing two different materials, titanium (Ti) and zirconia (ZrO2).
  
  
  METHODS
  Twelve implants were placed at bone level in the mandible of six beagle dogs (one in each side). At the same day of surgery one titanium abutment was screwed to the implant in one side (control group) and a zirconia abutment was screwed in the contralateral side. Nine months after implant/abutments placement, animals were sacrificed for histological analysis. Descriptive analysis was calculated for each variable and Wilcoxon test was applied to evaluate histomorphometric variables.
  
  
  RESULTS
  At the end of the study the soft tissue dimension at Ti and ZrO2were similar in all counterparts: biological width, the length of the barrier epithelium, length of the connective tissue, and the percentage of collagen fibers density. However, the percentage of blood vessels was higher for the Ti in comparison to ZrO2(5.11% ± 1.70 and 2.23% ± 0.98, respectively [P = 0.016]).
  
  
  CONCLUSIONS
  Peri-implant soft tissue histomorphology composition was similar in implant abutments made of ZrO2and titanium after 9 months of healing.
authors.affiliation: Department of Estomatology, University of Santiago de Compostela, Santiago de Compostela, Spain. jblanco@blancoramos.net.
authors.forename: Juan
authors.initials: J
authors.lastname: Blanco
authors.affiliation: Department of Estomatology, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Caneiro
authors.affiliation: Department of Estomatology, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Liñares
authors.affiliation: Department of Estomatology, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Batalla
authors.affiliation: School of Veterinary of Lugo, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Muñoz
authors.affiliation: Department of Estomatology, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Ramos
mesh_terms: D000818:Animals; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous; D015921:Dental Implants / Q000382:microbiology; D003764:Dental Materials / Q000494:pharmacology*; D004285:Dogs; D005881:Gingiva / Q000033:anatomy & histology / Q000187:drug effects*; D008334:Mandible; D023421:Models, Animal; D014025:Titanium / Q000494:pharmacology*; D015040:Zirconium / Q000494:pharmacology*
chemical_list: D015921:Dental Implants; D003764:Dental Materials; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide
keywords: animal experiments; biomaterials; soft tissue-implant interactions; zirconia abutment