Inferential Language Limits Claim to Preamble

In Bicon, Inc, et al. v. The Straumann Company, et al. (Fed Cir.; March 20, 2006) the court concluded that inferential language in the body of Claim 5 of U.S. Pat. No. 5,749,731 (right) for an emergence cuff 30 required the abutment 14 recited in the preamble:

5. An emergence cuff member for use in preserving the interdental papilla during the procedure of placing an abutment on a root member implanted in the alveolar bone of a patient in which
[a] the abutment has a frusto-spherical basal surface portion and
[b] a conical surface portion having a selected height extending therefrom comprising [c] a generally annular member formed of biocompatible synthetic plastic having first and second ends,
[d] a bore extending from the first to the second ends,
[e] the bore having a taper generally matching that of the conical surface portion of the abutment,
[f] the larger end of the bore being at the first end,
[g] the outer surface of the annular member forming a feathered edge with the bore at the first end of the annular member,
[h] the distance between the first and second ends being less than the height of the
conical surface,
[i] the diameter of the cuff member increasing in the direction going from the first end to the second end, and
[j] a radially inwardly extending flexible lip formed at the first end of the cuff member.

The court discussed several reasons why the detailed recitation of the features of the abutment were incompatible with Diro’s theory that the claim concerns only the features of the emergence cuff, and that the references to the abutment merely describe the intended use of the emergence cuff:

First, the requirement that the cooperating abutment have "a frusto-spherical basal surface portion" would have no meaning if the claim were limited to the structure of the emergence cuff. Diro argues that the claim requires only that the emergence cuff "interoperate with an abutment that does contain such an element." But nothing in Diro’s argument suggests how the shape of the basal surface portion of the abutment has any effect on the required structure of the emergence cuff. If there is no such effect, then under Diro’s proposed claim construction the recited "frusto-spherical basal surface portion%2