What is an overlay and how does it differ from a crown
A conventional crown requires the removal of approximately 65-75% of the original coronal tooth structure, healthy or not, to create the space the restoration requires. This preparation is irreversible. The tooth is permanently compromised and will depend on a prosthetic covering for the rest of its functional life.
An overlay is an indirect restoration that covers occlusal surfaces and, where indicated, vestibular surfaces, without involving the axial walls of the tooth when these remain intact. In worn teeth, where occlusal and incisal structural loss has already occurred pathologically, the preparation for an overlay can be minimal or entirely absent: the restoration compensates for tissue already lost, rather than sacrificing healthy tissue to create space.
The clinical consequence is significant. Adhesive bonding to residual enamel and dentine provides mechanical resistance comparable to that of a crown, with substantially lower biological cost. Long-term peer-reviewed studies report overlay survival rates above 85% at ten years with correct clinical indication, figures comparable to crown survival data over the same observation period.
When an overlay is not the right choice
Overlays are not appropriate in all cases. The clinical assessment must verify that sufficient residual enamel exists for reliable adhesive bonding, that the remaining coronal structure can support the restoration without fracture risk, and that occlusal forces are compatible with the planned material.
When wear has exceeded the threshold beyond which an overlay cannot achieve adequate retention and resistance, for example in teeth where most coronal structure has been lost and dentine predominates, the correct restoration is a crown. This decision is clinical, not ideological. Studio Calesini recommends overlays when overlays are indicated; recommends crowns when the crown is the only clinically sound option.
Materials for ceramic overlays in worn dentition
The material choice for an overlay in a patient with dental wear depends on the tooth position, expected occlusal forces, and aesthetic requirements.
Feldspathic ceramic, the material with optical properties most closely resembling natural enamel, is indicated for anterior restorations and posterior areas with moderate occlusal loading. In patients with bruxism or in posterior sectors subject to intense forces, lithium disilicate offers substantially higher fracture resistance with optical properties still superior to zirconia-based ceramics. The choice is not based on preference; it is based on the biomechanical situation of the specific tooth.
Studio Calesini produces ceramic restorations in its in-house laboratory. Direct supervision of ceramic stratification and chromatic characterisation allows the final result to be tailored to the morphology and colour of adjacent teeth, which in patients with generalised wear have often lost their original surface characterisation and require a more attentive aesthetic reading.
The adhesion issue in severely worn teeth
In teeth with advanced wear, the bonding surface often consists partly of exposed dentine. Adhesive bonding to dentine is clinically reliable but requires precise operative conditions: absolute isolation with a rubber dam, correct adhesive system selection, and moisture control. In cases where residual enamel is very limited, the adhesive prognosis must be assessed individually.
For patients considering adhesive overlay treatment after being quoted for full-arch crown rehabilitation, a structured second opinion can clarify which teeth are genuinely treatable with overlays, which require crowns, and whether the proposed sequence addresses the causative factor before restoration is undertaken.
A typical case
A patient with posterior wear who had been offered a ten-crown rehabilitation elsewhere. Reassessment showed sufficient residual coronal structure: the plan was reduced to adhesive overlays on six teeth, preceded by bruxism stabilisation with a night guard. Form and function were restored with minimal sacrifice of healthy tissue. This is an illustrative example, not an individual case: every clinical situation is assessed individually.