Restoring a lower fractured molar
The patient in this article presented with a fractured lower molar tooth. This tooth was asymptomatic but had sustained a fracture after years of effective restoration with an amalgam (Figure 1). The patient was a fit and healthy female.
The treatment options considered were:
1. Restoration with amalgam/composite
2. Indirect restoration with gold/porcelain/composite.
The patient sought an aesthetic durable restoration which would impart minimal damage to the remaining healthy tooth structure.
A micro filled posterior composite system was chosen as the restorative material SDI. A two-shade method was employed using A3 to restore the dentine and A2 to restore the enamel, giving an overall predicted A1 shade.
Local anaesthetic was applied and the tooth isolated using a wingless clamp and a heavy grade rubber dam (Figure 2). This was done following tooth shade selection. As the tooth is isolated, the enamel is liable to the effects of dehydration resulting in a lighter tooth shade temporarily.
The remaining amalgam restorations were removed under high volume aspiration and using a high-speed diamond bur. The tooth enamel margins were then prepared to enable the removal of the unsupported enamel and a single stage etch and bond resin was applied to the cavity. Two separate dentine cusp forms were placed and light cured using SDI Rok shade A3.
Once the mesio lingual and the disto lingual cusps were formed, dentine composite was also replaced on the fractured distal cusp. Shade A1 enamel SDI Ice was then veneered over the lingual cusps.
Enamel shade A1 was then added over the dentine shade placed at the distal cusp. Each layer of composite was light cured individually for 30 seconds. The remaining buccal cusps were also restored with A1 composite to recreate the cusp form.
The composites were all light cured repeated for 30 seconds. The cusps were not directly linked to avoid the effects of contraction shrinkage and also to aid in recreating the cusp anatomy and fissures. The distal marginal ridge was restored using A1 Rok (Figure 3).
Once the general cusp and occlusal forms were recreated, the composite was polished and a layer of unfilled resin (Bis GMA) used to glaze the composite and seal the occlusal fissures.
Diamond Paste (Diglaze) was then used (Figure 4) along with tungsten carbide finishing burs and rubber cups to refine the tooth form. This method of composite placement enabled a lifelike occlusal fissure pattern to be formed. A bristle brush was used to polish the finished restoration (Figure 5).
The end result provided an aesthetic functional and minimal restoration for this patient, and conformed to our original restoration criteria. Posterior composites placed under isolation can provide an excellent long-term option which may have fewer possible detrimental effects on pulp health when compared to cast restorations which require considerable tooth preparation.