Evaluation of UCLA implant-abutment sealing

• Published in: The International journal of oral and maxillofacial implants Vol. 29; no. 1; p. 113
• Main Authors: Ramos, Marcelo B, Pegoraro, Luiz F, Takamori, Esther, Coelho, Paulo G, Silva, Thelma L, Bonfante, Estevam A
• Format: Journal Article
• Language: English
• Published: United States 01-01-2014
• Subjects: Absorption; Chromium Alloys; Coloring Agents; Dental Abutments; Dental Implant-Abutment Design; Dental Leakage - diagnosis; Microscopy, Electron, Scanning; Random Allocation; Tolonium Chloride; Torque; Water
• ISSN: 1942-4434
• DOI: 10.11607/jomi.3217

To evaluate the effect of the presence of a prefabricated cobalt-chromium (CoCr) margin in a universal castable long abutment (UCLA) on the sealing capability and fit of the implant-abutment interface.
One-hundred twenty external hexagon implants (SIN) were divided into two groups (n=60 each) to receive UCLA abutments from six manufacturers (n=10 each) either with or without a CoCr margin (n=60 each). Abutments were cast and 12 groups were formed: M (Microplant), I (Impladen), S (SIN), Sv (Signo Vinces), T (TitaniumFix), and B (Bionnovation). Sealing was determined by placing 0.7 µL of 0.1% toluidine blue in the implant wells before abutment torquing. Implant-abutment samples were placed into 2.0-mL vials containing 0.7 mL of distilled water to maintain the implant-abutment interface, and aliquots of 100 µL of water were retrieved at 1, 3, 6, 24, 48, 72, 96, and 144 hour incubation times for measurement of absorbance in a spectrophotometer, and returned for repeated measurements. Two-way ANOVA (P<.05) and Tukey's test were used. Scanning electron microscopy (SEM) was used for observation of the implant-abutment fit.
Groups M, Sv, and T without the CoCr margin resulted in complete release of toluidine blue at 1 hour, whereas I, S, and B did so at 3, 24, and 96 hours, respectively. Complete leakage in abutments with the prefabricated margin occurred at 6 hours for S; 24 hours for Sv, T, and B; and 72 hours for M and I. Implant-abutment gaps were observed in all groups. A poorer fit was depicted for groups M and T without the CoCr margin.
Complete leakage was observed for all UCLA abutments regardless of the presence of the CoCr margin. Implant-abutment gaps were observed in all groups.