In a fixed three-unit bridge spanning teeth #1 to #4, what is the principal benefit of using #1 as an abutment adjacent to the pontic?

Correct answer: B. Resistance to vertical occlusal forces on the pontic

• A. Esthetics is not a meaningful consideration in the maxillary third molar region.
• B. CORRECT. An abutment on BOTH sides of the pontic converts the prosthesis into a supported beam, so vertical occlusal load on the pontic is distributed to abutments at either end. Without the distal abutment the pontic becomes a cantilever, and vertical load then generates a damaging tipping and torquing moment on the single remaining abutment.
• C. No design eliminates horizontal forces. Lateral loads are managed by occlusal scheme and cusp height, not by abutment number.
• D. A terminal abutment does not reduce the retention requirements of the preparation — if anything, a longer span demands more retention and resistance form.

Note: Law of Ante remains the underlying principle: the combined root surface area of the abutments should equal or exceed that of the teeth being replaced. Long spans flex — deflection increases with the CUBE of span length, so doubling the span makes it eight times more flexible.