Teachers will teach, but it is up to us to learn. Some lessons can only be learned after many years of experience.
In the mid – 1970’s the George Brown College denturist course was just getting started. Shortly thereafter, the college hired a professor with a very high ranking from the dentistry field. The Denture Therapists Program, as it was known back then, welcomed Dr. Paul Andrachuk to head the clinic program. Dr. Andrachuck was a prosthodontist who had taught the dentistry students at the University of Toronto for about 20 years. Dr. Andrachuk was in his mid-60s at the time. Prior to being hired at George Brown College, he was asked to be an examiner for the licensing exams that were set up for applicants who wished to be grandfathered into the recently created profession called denture therapy.
Dr. Andrachuk has a passion for teaching about denture prosthetics. A prosthodontist would first become a dentist and then specialize for several years in dentures, crown, bridge work, etc. With many years of experience in his private practice, he certainly was qualified to teach the young dentistry students and later denture therapy students.
Why we choose to teach denture therapists was not certain. Some say the university retired him too soon. Some say his passion for excellence drove him to teach the young eager-to-learn denture therapy students. Since their inception in 1954, the prosthodontists were struggling to wrestle away the denture patients from the dentists, much like denturists are doing right now, but to the dismay of the prosthodontists, dentists maintained the bulk of the patients. By this time, dentists had gotten very busy, or perhaps lazy, and were not making their own dentures anymore and were sending the work out to the newly flourishing dental laboratories. Prosthodontists were indeed making correct dentures, but the general dentists were sending out the dentures to be assembly-lined in sometimes huge factory-like settings by workers who were not taught what the prosthodontists were teaching about the correctness of dentures.
The late 1960s brought on the denturist movement in Ontario. These early and self-proclaimed denturists were saying that the creation of a specialty trainer profession (denturists) could do better dentures than the dentist/dental laboratory alliance. They would be trained much like the dentistry course that was taught to dentists on dentures, but these new denturists would also make their own dentures much like dentists used to from the 1850s to perhaps the 1930s.
These early and self-proclaimed denturists were saying that the creation of a specialty trainer profession (denturists) could do better dentures than the dentist/dental laboratory alliance. They would be trained much like the dentistry course that was taught to dentists on dentures, but these new denturists would also make their own dentures much like dentists used to from the 1850s to perhaps the 1930s.
Dentists did not like these newly licensed denture therapists of the 1970s, but some prosthodontists were feeling that dentists had this coming. They said dentists stopped making their own dentures and did not follow what the prosthodontists were teaching. One prosthodontist once told me that the dentists had most of the denture field to themselves, and they blew it by failing to follow the correctness that the prosthodontist professors had tried so hard to teach, thus the formation of denturists.
This is perhaps why Dr. Andrachuk decided to break ranks with the dentists and teach the denture therapy students. He was a marker for the grandfathered denturist exams and he saw that he could perhaps teach this new profession that he was not able to teach the young dentists. When a recent graduate dentist friend of mine found out that Dr. Andrachuk was our teacher, he said, "Oh no, Dr. Andrachuk was such a picky and boring teacher. You wouldn't believe how much we laughed and made fun of him behind his back!' These dentists knew that they were never going to make another denture once they got out of school. They would simply send it out to a dental lab to be made on an assembly line. If a denturist student thought that Dr. Andrachuk was specifically ignoring him during chair-side marking, then perhaps Dr. Andrachuk sensed that he was being made fun of behind his back, and it was a way to punish that student. He took his profession very seriously.
Dr. Andrachuk told us of his years in dentistry school and the event that nearly blinded him. He accidentally ran into a lamp in a dark room and severely injured his eye. He said he was lucky that he did not go completely blind. He retained a noticeable scar in his eye. The accident left him with less vision, and perhaps this is the reason that he took the bus to get to George Brown College every morning. It also made it difficult for him to see the fine detail required for fillings and other exacting work. He chose to train further and specialize as a prosthodontist. Those students who knew him always saw him feel in the patient's mouth as he explained an aspect of what he was teaching or checking for. He knew what entailed a correct denture through sight and feel of the oral anatomy.
So what was Dr. Andrachuk really trying to teach us? The answer lies in the cumulative 150 years since the first porcelain dentures were made.
So what was Dr. Andrachuk really trying to teach us? The answer lies in the cumulative 150 years since the first porcelain dentures were made. The early dentists had to experiment in the patient's mouth and with the design of the primitive dentures that they made. Remember, dentures were new and there were no rules or guidelines as to what entailed a correct-fitting denture. Through trial and error and with the guidance of the extensive anatomy and biology knowledge, they slowly developed the rules of correctness. Many rules were learned by long-term failure, destruction of the alveolar ridges, of natural teeth and TMJ damages from these early dentures. They slowly learned that a denture must satisfy many requirements. A denture must fit accurately, must function within the behaviour of the jaw's unique movement. It must allow phonetics and must look like natural teeth. Lastly and most importantly, the denture must inflict the least amount of damage the alveolar ridges, existing teeth, and the TMJ. Through their mistakes they found that their dentures had causes irreversible ridge damage, loosening remaining teeth, and TMJ damages. Correctness was imperative to minimize this destruction. He taught us that a partial denture that does not have rests in its design is correctly classified as a temporary partial denture because it knowingly causes damage that a cast partial can avoid.
Dr. Andrachuk taught us the systemic methodology that dentists were taught by their professors. This methodology is taught very similarly by most dentistry colleges in the world. In many poorer countries, dentists still do much or all of their own denture work. Labs are still a luxury in many countries. Since every mouth is different, dentists had to establish rules and guidelines and a consistent and repeatable methodology to direct them to establish the correct shape of dentures. This method was called border molding, usually done with various consistencies of the compound. Muscle molding is not a dental term. It was a misused term used by the lab industry. Muscle molding applies to body builders working out in gyms to develop specific muscles. Dr. Andrachuk taught us that there are muscles that we do activate during the shaping of compounds, but many more areas that encompass border molding are not in direct contact with any of the facial muscles.
Border molding is still very misunderstood today. Learning to border mold is not something that can be mastered in the three years of school. The teaching is a template that gets mastered with many years of dealing with all the different ridge shape variables. Dr. Andrachuk always said, "Never forget your border molding lessons." Extending a denture to cover the correct areas is so important. An under-extended lower denture, especially if it does not cover the major stress bearing areas, will cause excessive bone loss. Many implant dentures may very well be the result of these under extensions.
Dr. Andrachuk taught that a denture's major stress-bearing area must be well extended into the buccal shelf-external oblique ridge area. Many people in the dental field still do not know just how far this extension should really go. If you have a technician trimming dentures for you, this person must be taught the correct extensions of the dentures. Perhaps this is why so many lower ridges are mutilated and shrunk away by these severely under extended lower dentures.
Dr. Andrachuk taught that a relief chamber on the maxillary denture takes the major stress from the hard bony palate and places it onto the maxillary ridge where it should be. He taught us a method of determining the correct extension for the post dam area. There is, however, still much contention as to how and where the posterior seal should be. Some studies say that it is determined by the vibrating line, but there is an anterior vibrating line and a posterior vibrating line. Some say that it runs through the fovea palatine and hamular notches. Some say it runs through the attached, detached mucosa line. Dr. Andrachuk appeared to favour the junction of the hard and soft palate, in his final evaluation of our clinical dentures. I can still see him looking up into the air feeling the roof of the mouth for this line on my patient and telling me to extend the post dam with compound. I did and he was right, my denture did get much better suction.
Although Dr. Andrachuk's face bow protrusive bite to determine Condyle angles was the most practical method of the time, it has, however, been a contentious method since its inception in 1905. It was said that it was not accurate by the scholars of the time. Recent, more accurate, methods have indeed determined that readings tend to be low and inconsistent with the face bow protrusive bite. Today we have computers that can determine these angles with accuracy. He stressed that Condyle angles and Bennet angles were necessary values that should be used in denture construction.
Condyle angles can be a few degrees negative of Cambers Plane and as steep as 55 degrees at times. There can be variances between one Condyle to the other by as much as 30 degrees. Certainly the balanced occlusial scheme will be different in variations such as that. These measurements become even more important with implants especially with non-removables. The stress from a possible occlusial conflicts end up in the TMJ.
Another area he stressed was the determining of the buccal corridor during the bite block stage. The buccal corridor will keep you from doing resets and is a major component in the bite stage. The buccal corridor, in conjunction with the eminences of the eyeteeth, the plane of occlusion will the keep the posterior teeth on the lower ridges and guide the tooth set-up. He also stressed that the stabilized bite block and information recorded in the bite block should be kept and used for the set-up and try-in, notching out one tooth at a time and replacing it with the correctly positioned tooth in balanced occlusion. He said that stabilized bite block was absolutely necessary for bite registration accuracy.
When Dr. Andrachuk found out that I got my RDT license while in school, he called me a “Real Cracker Jack.” He then imparted more information on me than to some others, but he was also much harder on me in the marking of my work.
He taught us that you reline one denture and let it seat first before you reline the second. I once ignored him and relined both dentures at the same time and he got so angry with me that he chased me down the hall. Later, after graduating, I visited him at his house, and he told me I did not become Denturist of the Year because of the two relines.
He taught us that you reline one denture and let it seat first before you reline the second. I once ignored him and relined both dentures at the same time and he got so angry with me that he chased me down the hall. Later, after graduating, I visited him at his house, and he told me I did not become Denturist of the Year because of the two relines. Some of his favourite sayings were, "Read the impression" after you take it. If you have many sore spots "Check the bite." He said, "many dentures out there are worn by patients in spite of what was done.' This meant that there are many poorly made dentures out there, and even with all the errors in these dentures, people are somehow still wearing them. He did NOT mean that it was all right to make these wrong dentures. He was saddened and angered that people have to wear work that was so wrong and made with such little knowledge. There are many more things he expected us to learn and do. He really wanted us to maintain that high standard that he practiced and taught.
Did Dr. Andrachuk succeed? Firstly, he established the correct methodology and course outline for the denturist program. This was the template for all future denturism teachers at George Brown College to follow, and also the way it is taught to all dentists and prosthodontists.
The denturist has been taught to see the correct denture shapes before the impressions are taken. The stages of impression-taking are just a way of getting all the correct gum extensions that Dr. Andrachuk so clearly taught.
When a trained denturist looks in a patient's mouth and sees one of these very narrow under-extended lower dentures that are so common out there, he does not follow this narrow shape thinking that someone else must have known what is correct or what a patient can get used to, but instead he determines the correct extensions from all of Dr. Andrachuk’s teachings and makes that denture much wider and longer to the correct extensions and into the major stress-bearing areas. The denturist has been taught to see the correct denture shapes before the impressions are taken. The stages of impression-taking are just a way of getting all the correct gum extensions that Dr. Andrachuk so clearly taught. If a newly completed upper or lower border molded denture does not seem to fit snug enough, go over your denture first with a border molding compound to verify correctness and do a re-line on that new denture. You will be surprised as to what a difference it can make. I think he did succeed in his teachings, and once told us that our graduating class, the class of '79, was the best class he ever taught. Perhaps we listened more to him than his dentistry students. After all, we wanted to know everything he had to teach. We knew that we would use this knowledge every day.
Dr. Andrachuk liked to sip on a cheap coffee from the college's vending machine in his office. One morning I dropped into his office and I mischievously said, "Good morning Dr. Andrachuk." He said, "Good morning, Bert Rufenach." I then told him I had legally changed my first name from Bert to Doctor, and from now on when I greet you as Dr. Andrachuk in the morning you can greet me back as Doctor Rufenach! He slowly looked up from his coffee without even the faintest smile and slowly said, "Bert … you still have a lot to learn about the profession." He was so right - there was so much that I still had to learn from the lessons he taught us.
Dr. Andrachuk checking border molding with Brian Carr. Photo courtesy of Keith McKenzie.
About the author
Bert Rufenach is a lab technician in the family dental lab since 1969, RDT 1977, DD 1979. Director in the Denturist Association of Ontario. Author of many articles, lecturer, and