what is the purpose of a facebowAll of us as dentists were issued a facebow in dental school in order to fulfill our requirements. For some reason a majority of dentists tend to forget about the facebow the second they get out of dental school and go into practice. I think one of the main reasons as to why this happens is because we were only taught the technique of the facebow as students, but we really weren’t taught what the actual purpose of a facebow was.

When we first got into practice, our initial thought of the facebow's purpose was simply to aid in mounting models. We were taught in dental school that facebow only exists to help us mount the maxillary model on the articulator.

This thought process undoubtedly made us assume that we could simply perform this technique without using the facebow at all — we could tuck that facebow away and just pace the models in the middle of the articulator by hand or use things like a “stick bite.”

The purpose of the facebow is to transfer both esthetic and functional components from the patient to the articulator in a very efficient manner. The more accurately the models replicate those components, the more efficient we can be when we get back to the patient's mouth. From an occlusal and esthetic standpoint, the more closely the models translate the function, the less occlusal adjustment we'll have to do when we take the restoration back to the mouth or place our provisionals.

So, if you are not using a facebow, you must understand that the function and esthetic information of your mounted models may not be as accurate as you think it is. The effect of which will be noticed when you get back to the mouth and end up having to perform excessive adjustments for the occlusion and esthetics.

Gregg Kinzer, D.D.S., M.S., Spear Faculty and Contributing Author


Comments

Commenter's Profile Image Sunil Christopher
December 21st, 2013
wish to download
Commenter's Profile Image Mohan K
April 3rd, 2014
face bows are useless. there are studies to show that dentures made with or without them are equally good. that aside there are theoritical reasond why a face bow is useless. as for the tall claims made about tranferring aesthetic and blah blah -does the writer have any evidence for all that?
Commenter's Profile Image Emam
May 15th, 2014
how the facebow record is transferred into the articulator ?
Commenter's Profile Image Gary D.
January 4th, 2016
The usefulness of ANY tool is dependent on the user. If a person believes that a facebow is useless I can only assume it's because he or she cannot gain useful information from utilizing it. I gain a lot of information from using my facebow, so I use it often. I prefer my casts on an articulator, and I like them mounted in a way that mimics the position of the maxillary teeth relative to the horizon, the floor, and the bench top. I could provide for this in a number of different ways, but since I don't utilize those other ways - I don't gain useful information from them - doesn't mean they are useless to others. When planning a case you might prefer another way of positioning casts so that you can plan for a desired outcome, such as the incisal and occlusal planes on a denture, and that is perfectly OK as long as you get the result you are after. Is the facebow a mandatory part of the diagnostic and planning process, absolutely YES, for ME. In other hands it might be considered useless. If the outcome attained is the one each clinician was after, the tools utilized to get there are merely a choice and a preference, and I don't believe anyone would choose to use a tool they found useless.
Commenter's Profile Image Eric M.
January 5th, 2016
Useless? I'm a hobbyist woodworker and have a few tools in my shop that have sat on the shelf for a while collecting dust. I suppose I could say "these tools are useless", but it's only because I haven't spent the time to learn how to use them. To other woodworkers, they seem to be indispensable. Good for anyone that's figured out another way to transfer esthetic information from the patient to the articulator, without using a face bow/ear bow. Perhaps you could share your technique?
Commenter's Profile Image Scott N.
January 8th, 2016
The facebow records the 3-dimensional relationship of the maxillary teeth relative to anatomic reference landmarks of the head and permits the anatomic relationships of the head to be transferred to an articulator. The objective of any articular mounting is to relate the same relationship of the teeth to its axes that the teeth in the mouth occupy to the axes of the condyles. (eHuman / Grainger; Practical Procedures in Oral Rehabilitation, 1962) The objective of any articular setting or adjustment is to reproduce on a mechanical instrument the paths of motion of the axes of the patient. Accurate impressions on such an articulator which will reproduce the actual anatomic relations, allows the operator to put the patient on the lab bench. However, the location of centric relation and a centric bite without recording the paths of the joint is of little functional value. (Grainger; Practical Procedures in Oral Rehabilitation, 1962)
Commenter's Profile Image Gregg H.
January 10th, 2016
As a dentist/technician I can tell you that the difference in using a facebow/articulator mounted casts and a stick bite with a simple hinge articulator is the disimliar arcs of closure between the 2 instruments. The amount of intraoral adjustments is significantly higher when the hinge of the instrument is equal in height to the maxillary plane, whereas, the axis of rotation on the patient is much higher than the maxillary plane thereby having a different arc of closure. It's just engineering.