Which of the following statements regarding Class III interproximal lesions is the exception?

In the context of Class III interproximal lesions, the statement about unsupported facial enamel being removed is the exception because it overlooks a critical aspect of preserving tooth structure while ensuring effective treatment outcomes. Class III lesions specifically affect the mesial or distal surfaces of anterior teeth, typically located below the contact area and less often on the facial portion.

When preparing for a Class III restoration, the goal is to conserve as much healthy tooth structure as possible. Leaving unsupported facial enamel can be advantageous as it may provide an area for internal bonding of the composite material, helping to enhance the strength and integrity of the restoration. Thus, the practice is to selectively remove enamel that is highly compromised rather than completely eliminating all unsupported facial enamel. This approach not only helps preserve the tooth but also improves the longevity and aesthetic appeal of the restoration.

The other statements are aligned with accepted practices for Class III lesions. The characterization of caries often being apical to the interproximal contact reflects the typical progression pattern of decay in these areas. The preference for the lingual approach in cavity preparation is a well-established method that enhances visibility and access while minimizing the loss of facial enamel.