Faceplate

The faceplate was the metal face plating of the Cyberman helmet. (WC: Real Time/AUDIO: Real Time)

Variants
Certain Cyber-Leaders, also designated Cyber-Lords, had black facial plating with visible brains behind the forehead. (TV: The Next Doctor, A Good Man Goes to War, GAME: Blood of the Cybermen) In Pete's World, the Cyber-Controller John Lumic also had a visible brain. (TV: The Age of Steel)

A Cyber-Controller which used Borg technology sported an modified Cyber-helmet with a visible brain; its right side handle was replaced with a tube connected its faceplate's right eye, which was augmented with a Borg implant. (COMIC: Assimilation²)

Cybershades uniquely had bronze faceplates. (TV: The Next Doctor)

Individual cases
Partially converted on Telos, Gustave Lytton's head was supported by an incomplete Cyber-helmet without facial plating. Before his conversion could be completed, Lytton was killed defending the Sixth Doctor from the Cyber-Controller. (TV: Attack of the Cybermen)

Partially converted during the Battle of Canary Wharf, Lisa Hallett's head was supported by an incomplete Cyber-helmet without facial plating. Following a failed conversion which resulted in his death, parts of a Cyber-helmet's face were seen embedded into that of Dr Tanizaki. (TV: Cyberwoman)

Despite being detached from its body, the helmet of a damaged and automated Cyberman suit made a failed attempt to replace its expired organic components by assimilating Amy Pond. To that end, the faceplate split in two, emptying the helmet of a humanoid skull. As it attempted to assimilate Amy, the helmet repeatedly opened and closed before it eventually fired a dart at Amy's neck, which rendered her unconscious. Ultimately, however, the Cyber-suit was neutralised by Rory Williams. (TV: The Pandorica Opens)

Following his cyber-conversion, Danny Pink removed his faceplate to reveal himself to Clara Oswald. (TV: Death in Heaven)

The Cyber-helmet known as Handles sustained damage to its faceplate. (TV: The Time of the Doctor)