Journal of Oral Implantology February 2014 - (Page 31)

RESEARCH Implants With Internal Hexagon and Conical ImplantAbutment Connections: An In Vitro Study of the Bacterial Contamination Simonetta D'Ercole, DDS, PhD1 Antonio Scarano, MD, DDS1 Vittoria Perrotti, DDS, PhD1 Jorge Mulatinho, DDS2 Adriano Piattelli, MD, DDS1* Giovanna Iezzi, DDS, PhD1 Domenico Tripodi, MD, DDS1 Prevention of microbial leakage at the implant-abutment junction is a major challenge for the construction of 2stage implants in order to minimize inflammatory reactions and to maximize bone stability at the implant neck. The aim of the present in vitro study was an evaluation of the leakage observed over a period of 28 days in Cone Morse taper internal connections and in screwed-abutments connections. In the present study 10 specimens of Cone Morse (Group 1) and 10 of internal hexagon (Group 2) implants were used. The inner parts of 5 implants per group were inoculated with Pseudomonas aeruginosa (PS) suspension and 5 implants per group with Aggregatibacter actinomycetemcomitans (AA). The possible penetration of bacterial suspension into the surrounding solution was determined by the observation of turbidity of the broth. In Group 1, bacterial contamination was found in 3 out of 5 implant-abutment assemblies seeded with the PS and in 2 samples out of 5 in the assemblies seeded with AA, with a total of leaked assemblies in this group of 5 out of 10. In Group 2, bacterial contamination was found in 4 out of 5 implant-abutment assemblies seeded with the PS, and in 4 out of 5 samples seeded with AA, with a total of leaked assemblies of 8 out of 10. The present data confirm the reported high permeability to bacterial leakage of screw-retained abutment connections, and the lower infiltration rates-although not significantly-of Cone Morse taper internal connections. Key Words: bacterial contamination, dental implants, implant-abutment connections, microbial leakage INTRODUCTION B acterial contamination of implants can occur.1 Bacterial leakage through the implant-abutment junction (IAJ) has already been reported.1 Prevention of microbial leakage at the IAJ is a major challenge for the construction of 2-stage implants in order to minimize inflammatory reactions and to 1 Dental School, University of Chieti, Italy. ˜ Private Practice, Sao Paulo, Brazil. * Corresponding author, e-mail: apiattelli@unich.it DOI: 10.1563/AAID-JOI-D-11-00121 2 maximize bone stability at the implant neck.2 Several investigators tried to quantify microbial leakage of dental implants,2 but the literature concerning the quantification of microleakage and fluid passage between different connection designs is sparse.3 This leakage could determine an inflammatory process in the peri-implant tissues near the level of the alveolar bone crest. 4,5 Broggini et al 6 demonstrated an increase in inflammatory cells in the peri-implant soft tissues at the level or slightly coronal to the IAJ. Fistulae in the peri-implant soft tissues have been frequently reported.4 Even Cone Morse taper imJournal of Oral Implantology 31

Table of Contents for the Digital Edition of Journal of Oral Implantology February 2014

Evolution of Bone Grafting for Improved Predictability
Electrochemical Behavior of Titanium in Artificial Saliva: Influence of pH
Efficacy of Antibacterial Sealing Gel and O-Ring to Prevent Microleakage at the Implant
Wired/Classic and Wireless/Periotest ‘‘M’’ Instruments: An In Vitro Assessment of
Altered Position of the Medial Lingual Nutritional Foramina at Different Stages of Alveolar
Genotoxicity of Endosseous Implants Using Two Cellular Lineages In Vitro
Implants With Internal Hexagon and Conical Implant-Abutment Connections: An In Vitro
Stress Distribution Around Maxillary Anterior Implants as a Factor of Labial Bone Thickness
Peri-Implant Biomechanical Responses to Standard, Short-Wide, and Mini Implants
Removal Torque Analysis of Implants in Rabbit Tibia After Topical Application of
Nonprocessed Adipose Tissue Graft in the Treatment of Peri-Implant Osseous Defects in
Assessment of the Effect of Two Occlusal Concepts for Implant-Supported Fixed
Nerve Damage Assessment Following Implant Placement in Human Cadaver Jaws:
Dental Implants: Early Versus Standard Two-Stage Loading (Animal Study)
Intravenous Sedation for Implant Surgery: Midazolam, Butorphanol, and
Nanocrystalline Hydroxyapatite-Based Material Already Contributes to Implant Stability
Two Neglected Biologic Risk Factors in Bone Grafting and Implantology: High Low-Density

Journal of Oral Implantology February 2014