Implants with internal hexagon and conical implant-abutment connections: an in vitro study of the bacterial contamination.
Prevention of microbial leakage at the implant-abutment junction is a major challenge for the construction of 2-stage 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.
1  Dental School, University of Chieti, Italy.
Simonetta
S
D'Ercole
Antonio
A
Scarano
Vittoria
V
Perrotti
Jorge
J
Mulatinho
Adriano
A
Piattelli
Giovanna
G
Iezzi
Domenico
D
Tripodi
D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D058491:Bacterial Load; D001431:Bacteriological Techniques; D059605:Dental Implant-Abutment Design; D015921:Dental Implants / Q000382:microbiology*; D003763:Dental Leakage / Q000382:microbiology*; D004866:Equipment Contamination; D016946:Gram-Negative Aerobic Rods and Cocci / Q000302:isolation & purification*; D006801:Humans; D009391:Nephelometry and Turbidimetry; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D013053:Spectrophotometry; D013499:Surface Properties; D013997:Time Factors
D015921:Dental Implants