Mouth Gag Types: McIvor, Boyle-Davis, Dingman, Jennings and Molt
Instrument guides
Mouth Gag Types: McIvor, Boyle-Davis, Dingman, Jennings and Molt
How tongue blade gags such as the McIvor and Boyle-Davis differ from cheek and side gags, which blade sizes we make, and where the designs came from.
A mouth gag holds the mouth open during oral, throat and maxillofacial surgery. There are two main kinds. Tongue blade gags such as the McIvor, Boyle-Davis and Dingman have a frame that rests on the upper teeth or gums and a blade that holds the tongue down, giving a clear view of the throat and palate. Side and cheek gags such as the Molt, Jennings, Roser-Koenig and Heister open between the jaws from the side. Choose by the access you need and the patient's size.
Where does the Boyle-Davis gag come from?
The Wood Library-Museum of Anesthesiology records that the surgeon Edward Sewall described a mouth gag in 1910, that the anesthesiologist S. Griffith Davis modified it for tonsillectomy, and that Harvey Cushing described Davis's version in 1912 (the Davis gag at the Wood Library-Museum). The English anesthetist Henry Boyle bought one on a visit to the United States in 1921 and published it the following year, and it became known in Britain as the Boyle-Davis gag. It made dissection tonsillectomy practical with the patient's head extended, and the same principle runs through the McIvor and Dingman gags used in cleft palate and maxillofacial surgery.
Which mouth gags do we make?
| Gag | Sizes | Type | Use |
|---|---|---|---|
| McIvor, complete set, frame or single blades | Blades 75, 85, 100 x 25 mm | Tongue blade | Palate and oral surgery |
| Boyle-Davis, complete set, frame left, right | Set with blades | Tongue blade | Tonsillectomy and throat |
| Dingman, complete set | Set with blade | Tongue blade with cheek retractors | Cleft palate and oral surgery |
| Jennings | 10.5 to 16.5 cm | Side ratchet | Opening and holding the jaws |
| Molt | 11 or 13 cm | Side, scissor action | Opening the jaws between the teeth |
| Roser-Koenig | 16 or 20 cm | Side, ratchet | Prising open a closed jaw |
| Heister | 13 cm | Side, screw | Gradual opening |
| Denhart | 13 cm | Side | Oral procedures |
Tongue depressors for examination and surgery: Mayo, Bruening, Tobold, Andrew.
How do you choose a gag and blade?
- Access. For the palate and throat, a tongue blade gag. For the teeth, jaws and cheek side, a side gag.
- Blade length. The blade should reach past the back of the tongue without pressing on the larynx. Children need shorter blades than adults, which is why McIvor and Boyle-Davis gags are sold with several blades.
- Frames and blades. Buying the complete set avoids blades that do not fit a frame. Spare blades let one frame serve children and adults.
How should gags be cleaned?
Take the blades off the frame for cleaning, and clean the ratchet and the blade slot. Check that the ratchet holds firmly under load before every use. Never leave instruments in saline, because it causes corrosion. Our instrument care guide gives the full routine, and the CDC guidance on cleaning instruments before sterilization explains why cleaning comes before the autoclave.
Frequently asked questions
What is a McIvor mouth gag used for?
Holding the mouth open and the tongue down in palate, cleft and oral surgery. Our sets come with blades of 75, 85 and 100 mm.
What is the difference between the Boyle-Davis and the McIvor?
Both are tongue blade gags. The Boyle-Davis was developed for tonsillectomy. The McIvor is widely used in cleft palate and oral surgery.
What is a Molt mouth gag?
A side gag with scissor action that opens the jaws from between the teeth.
Can mouth gags be autoclaved?
Yes. Separate the blades from the frame first.
Related instrument guides
- Maxillofacial retractors
- Orthognathic osteotomes and separators
- Maxillofacial elevators and bone instruments
- Surgical suction tubes
Order mouth gags
See the full maxillofacial instrument range. For a set for a hospital, a clinic or a distributor, send us your list and we will send you a quote.