Bone-anchored Prostheses In The Management Of Auricular Defects

Objective:To prepare a base for the management of auricular defects with boned-anchored prosthese .This article describes a technique to design auricular prosthese and a method for devising osseointegrated constructions,and investigates the biocompatibility of ally Ti-6Al-4V in the temporal bone of rabbit.Methods:15 rabbits were selected to carry out experiment .The auricular prosthese were fabricated with silicon rubber or MMA by the technique of dentistry ,and the implants were made of alloy Titanium-6-Alummum-4-Vanadium (Ti-6Al-4V). lag base Imbeded in temporal bone , parameters of hepatic and renal function were individually measured at the end of 0,1,3,6 months .Levels of Ti and V in blood serums of rabbits were respectively examined at the time of 1,3,6 months and four rabbits selected at random were killed at the same time .These temporal bones containing implant were observed by naked eye,radiograph,histology(microscope,elytrorrhaphy).Auricular prostheses were anchored on experimental rabbits at the latter two terms。Results:(1) Auricular prostheses fabricated by MMA are of re-processing,while those by silicon rubber are of a sense of beauty . Both are characterestic of imitative outline .(2) There are slight changes in parameters of hepatic and renal function and Level of Ti and V in blood serums of rabbits among different periods. No significant differences are observed statistically. (3)Histology observations demonstrate that the surface of implanted material is covered by fibrous tissues during 1～3 months while the inderphase between bones and materials are coveredby bone trabecula gradually. Bone trabecula is deranged early and well-arranged after 6 months.(4) Auricular prostheses fixed by lag bolt are stable and secure in more than 2 weeks. Conclusions:Alloy Ti-6Al-4V implanted in temporal bone is of good biocompatibility and firm osseointegration ；The contour of auricular prosthese fabricated by MMA and silicon rubber is life-like and the procedures are simple；Auricular prosthesis combined with Ti-6Al-4V is an alternative for patients with auricular defects .