title: Randomized, controlled histologic and histomorphometric evaluation of implants with nanometer-scale calcium phosphate added to the dual acid-etched surface in the human posterior maxilla.
abstract: BACKGROUND
  Placement of dental implants in the posterior maxilla has been associated with higher rates of failure that are due, in part, to the poor bone quality of this region. The purpose of the present study was the histologic and histomorphometric evaluation of the bone around a new implant surface treatment created by a deposition of nanometer-sized calcium phosphate particles added to the dual acid-etched surface.
  
  
  METHODS
  One custom-made 2 x 10-mm site evaluation implant (SEI) with this novel treatment surface (test) and one SEI with the dual acid-etched surface without treatment (control) were placed in the posterior maxilla of 15 patients. All SEIs were retrieved after 2 months and evaluated under confocal laser scanning microscopy (CLSM) and by light microscopy for histomorphometric analysis of the bone-implant contact (BIC).
  
  
  RESULTS
  Histologic observations in control SEIs showed formation of new bone around the implant surface; however, it was not always in direct contact with the entire perimeter of the threads. The mean BIC was 19% +/- 14.2%. Test SEIs showed peri-implant bone tightly contacting the implant surface and better adapted to the threads. Three-dimensional reconstruction of sections obtained using CLSM showed the intimacy of the contact between bone and test SEI surface through the entire thickness of the specimens. The mean BIC was 32.2% +/- 18.5%.
  
  
  CONCLUSIONS
  After 2 months of healing, comparison of the BIC values showed a statistically significant greater mean BIC for test SEIs than for controls. The clinical implications of these results included shortening of the implant healing period and earlier loading protocols.
authors.affiliation: Operative Unit of Stomatology and Oral Science of Center for Excellence on Aging - G. d'Annunzio, University Foundation and Department of Stomatology and Oral Science, University of Chieti-Pescara, Chieti, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Orsini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Piattelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Scarano
authors.forename: Giovanna
authors.initials: G
authors.lastname: Petrone
authors.forename: James
authors.initials: J
authors.lastname: Kenealy
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
authors.forename: Sergio
authors.initials: S
authors.lastname: Caputi
mesh_terms: D000134:Acid Etching, Dental; D001641:Bicuspid; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008437:Maxilla; D018613:Microscopy, Confocal; D008875:Middle Aged; D008963:Molar; D053758:Nanoparticles; D016348:Osseointegration / Q000502:physiology*; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D013499:Surface Properties
chemical_list: D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D015921:Dental Implants; C020243:calcium phosphate