Biomaterials Focus Group -
Research Highlight 2

Gallium Alloy and Ceramics - Alternatives to Dental Amalgam, a project by Assoc Prof Jennifer Neo, Prof John Osborne, Prof Chew Chong Lin and Assoc Prof Adrian Yap

In a research project headed by Assoc Prof Jennifer Neo which examined the clinical use of gallium alloy and ceramic inlays as alternative restorations to amalgam, two clinical studies have been reported. The first study, entitled Clinical evaluation and microstructural analysis of a direct placement gallium restorative alloy, assessed the clinical performance of a direct placement gallium alloy sealed with an established dentine adhesive system. The control restoration was the Tytin amalgam. A significant percentage of the gallium restorations (43%) had to be removed from teeth which developed sensitivity and those which became devitalised or had fractured restorations. Many gallium restorations were tarnished, and had internal cracks and were corroded. Compared with the Tytin amalgam, gallium restorations demonstrated a high clinical failure rate, and are therefore unsuitable for usage as a routine restoration. The second study, entitled "A 4-year clinical evaluation of copy milled ceramic inlays", evaluated the marginal integrity of milled ceramic inlays after a 4-year period in the oral cavity. The findings revealed a failure in 20% of the ceramic inlays which were due mainly to fracture. Compared with earlier recalls, these ceramic restorations showed increased marginal discrepancy and marginal discolouration. These data do not favour the use of ceramic inlays as long-term replacements to amalgam.

Figure 1: First and second mandibular molars prepared to recieve Celay inlays.

Figure 2: Celay inlays placed.

Figure 3: #15 - restored with Gallium alloy
#16 - Tytin (high copper amalgam).

Figure 4: #14 - restored with Gallium Alloy.

Figure 5: #14 - fracture of buccal cusp.

[ Previous | Main | Next ]

For any commments and suggestions, please feel free to email A/Prof SB Keng