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Updated: Jun 18, 2026

Establishment of a Murine Pulp Exposure Model with a Novel Mouth-Gag for Pulpitis Research
Published on: October 27, 2023
The Heister mouth gag or 'speculum oris'
1Mildura, Victoria.
Abstract:
The Heister mouth gag is attributed to Lorenz Heister, an eighteenth century German surgeon. There is no evidence that Heister designed the mouth gag, the earliest known illustration of which is in the 1719 edition of Heister's Chirurgie. In the first half of the twentieth century, the Heister gag was widely available for use during anaesthesia. It is now rarely used by anaesthestists, but occasionally used by surgeons during oral surgery.
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