title: Primary Apical Stability of Tapered Implants Through Reduction of Final Drilling Dimensions in Different Bone Density Models: A Biomechanical Study.
abstract: OBJECTIVE
  A biomechanical study of the primary apical stability obtained in tapered implants through the reduction of final drilling dimensions in different bone density models.
  
  
  METHODS
  An in vitro study of maximum insertion torque and primary stability based on the resonance frequency analysis (RFA) of 24 conical implants measuring 13 mm in length and 3.75 and 4.20 mm in diameter, randomly inserted in 10-mm sockets prepared in 4 polyurethane blocks with a density of 15, 20, 30, and 40 pounds per cu ft, respectively, reducing the diameter of the final drill at constant speed (400 rpm) to obtain exclusive 4 mm anchoring of the apical third of each implant.
  
  
  RESULTS
  The decrease in drilling diameter resulted in an increase in the insertion torque and implant stability quotient (ISQ) values in all implants, although without reaching statistical significance. In turn, a significant direct correlation was found between increasing bone analog block density and the insertion torque and ISQ values.
  
  
  CONCLUSIONS
  Under the conditions of this study, the primary apical stability obtained may be more dependent on bone density than on reduction of the final drilling diameter.
authors.affiliation: *Associate Professor of Oral Surgery and Implantology and Biotechnology Coordinator of Unit of Morphopathological Research, University of Carabobo Dental School, Valencia, Venezuela. †Professor-in-Chief of Oral and Maxillofacial Surgery, Santa Maria University Dental School, Caracas, Venezuela. ‡Assistant Professor of Oral and Maxillofacial Surgery and Dental Research, Dr. Raul Vicentelli Institute, Central of Venezuela Dental School, Caracas, Venezuela. §Cathedratic of Oral and Maxillofacial Surgical Pathology, Chairman of Oral and Maxillofacial Surgery, University of Barcelona Dental School; Coordinator of the Research Group of Maxillofacial Pathology and Dental Therapeutics, IDIBELL, Head of the Department of Oral Surgery, Implantology and Maxillofacial Surgery, TEKNON Medical Center, Barcelona, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Sierra-Rebolledo
authors.forename: Marvis
authors.initials: M
authors.lastname: Allais-Leon
authors.forename: Paul
authors.initials: P
authors.lastname: Maurette-OʼBrien
authors.forename: Cosme
authors.initials: C
authors.lastname: Gay-Escoda
mesh_terms: D001696:Biomechanical Phenomena; D015519:Bone Density; D003758:Dental Implantation, Endosseous / Q000379:methods; D015921:Dental Implants; D003799:Dental Stress Analysis; D006801:Humans; D066298:In Vitro Techniques; D008954:Models, Biological; D019415:Torque
chemical_list: D015921:Dental Implants