Retrieval study of stainless steel and titanium miniplates and screws used in maxillofacial surgery

Abstract

The surfaces of 43 stainless steel miniplates and 19 titanium miniplates with matching screws of the same materials were studied after retrieval with respect to surface degradation. Stereomicroscopic and scanning electron microscopic (SEM) examinations were performed, and surface roughness and hardness of the plates were measured. Defects of mechanical nature which could be traced back to handling procedures were found in all stainless steel and titanium devices. Metal tongues and splinters were occasionally found associated with screw threads and in the periphery of plate screw holes. Corrosion defects were observed in about 1/5 of the stainless steel plates, restricted to the countersink area. Corrosion defects were also found on the chamfer of the underside of stainless steel screw heads. None of the titanium devices showed evidence of corrosion. The surface roughness of the titanium plates was higher than for the stainless steel plates. The retrieved plates were rougher than the new plates.

Local effect of titanium implant corrosion: an experimental study in rats

“…In some cases the products of corrosion were found around the blood vessels, in keeping with the findings of MEACHIM and WILLIAMS 19 and TORGERSEN et al 33 , in a histological study of soft tissue adjacent to titanium implants. The observation of metal particles located intracellularly or in association with vessels may represent a biological response aimed at eliminating the foreign material 19,30,32 .…”

“…The formation of metal particles increases the surface area available for oxidation and ion release 9,27 . Owing to the lack of consistent information on the long-term effects of metal implants on the human body, an international study group has suggested that all non-functional implants should be evaluated for removal 31,32 .…”

Análise de falhas de implantes cirúrgicos no Brasil: a necessidade de uma regulamentação adequada

“…Verificou-se que a composição química da placa (inicialmente declarada como sendo liga Ti-6Al-4V ) não estava de acordo com as exigências mínimas da norma NBR-ISO: 5832-3 (ABNT, 1997b) para esta liga (Tabela 3). Entretanto, placas usadas em cirurgias buco-maxilo-faciais geralmente são fabricadas em ligas de titânio comercialmente puro (CP Ti), e de fato a composição quí-mica e o tamanho de grão metalúrgico da placa analisada estão de acordo com os requisitos da norma NBR-ISSO: 5832-2 (ABNT, 1997a), grau 1 (CP Ti) (Torgensen & Gjerdet, 1995). A composição química dos parafusos se adequou, via de regra, às especificações para a liga Ti-6Al-4V.…”

Surface Analysis of Indigenous Stainless Steel Miniplates Used in Facial Fractures

“…Metal tongues and splinters were also seen associated with screw threads and in the periphery of plate screw holes. Jorgensen and Gjerdet [2] in their study of SS and titanium miniplates and screws concluded that Defects of mechanical nature were found in all SS [8].…”