Clinical and microbiological evaluation of internal-hex vs combined Morse-taper/internal-hex implant systems: A case report [Valutazione clinica e microbiologica di impianti a connessione conometrica rispetto a impianti a connessione esagonale: Caso clinico]

Objectives: Dental implant failure secondary to systemic disease, surgical trauma, biomechanical aspects, etc. can be classified as early or late. The aim of the present case report is to compare two different implant-abutment connection systems used in the same patient: an internal-hex system used in the upper arch and a combined morse-taper/internal-hex system in the lower arch. Material and methods: Two full-arch implant-supported rehabilitations were performed with two different implant systems in a completely edentular 65-year-old man. Impressions were obtained to develop the study models and create prosthetically-guided surgical templates. Three and five months later, samples from the implant-abutment connections and peri-implant soft tissues were subjected to real-time PCR-based microbiological analysis. Results and conclusions: Microbiological analyses revealed that the compositions of the subgingival peri-implant biofilms were similar with the two implant systems; at the level of the connection, better sealing was observed with the combined morse-taper/internal-hex implant system. The 3- and 5-month follow-up showed no sign of implant failure or complications (biological or mechanical). No clinical and/or radiographic differences were observed between the two implant abutment connections. © 2010 Elsevier Srl.