What is the importance of rounded surfaces preparation of a veneer?

The importance of rounded surfaces preparation for a veneer primarily relates to preventing areas of stress concentration. When the edges and surfaces of a veneer preparation are sharp or have abrupt transitions, they can create points where stress is concentrated during functional forces, such as biting and chewing. Rounded surfaces help distribute the forces more evenly across the veneer, reducing the risk of fracture or failure over time.

Additionally, rounded preparations allow for better bonding between the veneer and the underlying tooth structure because they increase the surface area for adhesion and reduce the likelihood of debonding at high-stress points. This approach is essential not only for the longevity of the restoration but also for maintaining the integrity of the tooth underneath.

The concepts of bulk reduction and aesthetic enhancement are also relevant but are secondary to the primary goal, which is to ensure that the restoration remains functional and structurally sound in the long term.