(1)
Flinders University of South Australia School of Medicine, Adelaide, SA, Australia
There is evidence of dental procedures being performed thousands of years ago but until quite recently most dental conditions were managed by extraction. In the Sushuta Samhita, which was written more than 1500 years ago, surgical students were told to practice extracting teeth from the jaws of dead animals [1, pp. 71–73]. The Etruscans made dentures from gold and made dental crowns from human teeth [2]. In France in the early eighteenth century Pierre Fauchard (1678–1761) created the field of dental surgery [3]. Fauchard recognized the association between consumption of sugar and tooth decay and described a range of dental procedures in Le Chirurgien dentiste, ou Traité des dents (The dental surgeon or a Treatise of teeth) first published in 1728. In the book Fauchard explained how lost teeth could be replaced by dental prostheses constructed from ivory and bone. John Hunter’s The Natural History of Human Teeth published in 1771 became the ultimate reference for dental anatomy and his more Practical Treatise on the Diseases of the Teeth was published in 1778. In the Treatise Hunter wrote extensively on transplantation of teeth, then widely advocated as a substitute for dentures [4].
In the nineteenth century advances in dental knowledge and development of new materials and technologies meant teeth could be conserved and restored using gold or tin [5]. One of Hunter’s pupils, Joseph Fox, wrote the first text on orthodontics which was first published in 1803 [6, pp. v–vi]. Dental schools were established in the United States and Europe to train a new healthcare professional, the dentist, and as with many healthcare disciplines at this time, novices learnt new techniques on simulators before they were attempted on patients.
Early Modern Simulators in Dentistry
“Mr. Oswald Fergus exhibited and explained an apparatus which he had devised, and to which he had given the name of “The Dental Phantom.”
“As he had said elsewhere, it was expected, and rightly expected, that students should not be let loose to work their will on their suffering fellow creatures without first having acquired a proper efficiency. Mr. Fergus thought that the methods hitherto adopted in teaching were deficient, inasmuch as they did not supply the students with the surroundings which would be found in actually treating a patient.” Report of meeting (1894) [7, pp. 272–273]
A problem with using complete skulls to practice dental procedures is that new teeth can’t be put back in the sockets [8]. Edward Oswald Fergus (1861–1946), a dental surgeon who had trained in Glasgow and Pennsylvania, presented a dental simulator at an Odontological Society conference in 1894. He explained that when students currently practised on a tooth held in a vise (clamp) the tooth might not be fixed in a realistic orientation and access to the tooth did not have the constraints students would face in clinical practice. The consequence of both these issues was students did not always learn the skills needed to treat patients [7]. Fergus later claimed priority for his invention [9] which he called a “Dental Phantom” (Zahnaertzliches Phantom) but it was not the first.
At a meeting of the Central Association of German Dentists in Leipzig in August 1877 Eduard Fleischer, a dentist in Komotau, Bohemia, made a short presentation on teaching dental procedures and then presented an invention he called a “dental phantom” [10, p. 414] Fleischer reported that dental students currently practised on cadavers and then started working on patients too soon. He said that phantoms were used for teaching obstetrics, ophthalmology, and laryngoscopy students and he wanted to make a better phantom for teaching dental students. The dental phantom was described in some detail and with an illustration (see Fig. 11.1) in an article published in 1878 [11]. The simulator had a life-size head on an adjustable stand that could be fixed to a bench top with a clamp. The teeth, made from bone or ivory, were quite realistic and implanted in pink Gutta-percha1 that represented the gums. The phantom was supplied with a complete set of perfect, intact teeth, a full set of teeth in which every one of them had a carious opening and a number of different types of teeth roots. The head was on a ball-and-socket and could be adjusted to hold any natural position, the amount of mouth opening was adjustable and tempero-mandibular joints could be adjusted independently to create different bites.
Fig. 11.1
The dental phantom by Fleischer 1877). A small balloon was filled with water and connected to fine tubes to simulate saliva [11]
Some steps of dental restorative procedures needed to be kept dry and Fleischer’s phantom had a simulated salivary apparatus. The salivary openings were connected by fine brass tubes to a small water-filled balloon so that students had to take appropriate preventative measures to avoid contamination of the operative site.
Another dental simulator which was described in an article published in 1878 had similar features to the one designed by Fleischer but they were achieved in different ways. The head of the simulator was on a stand that stood on the floor and the height could be adjusted (see Fig. 11.2). The teeth were held in a socket in the jaw consisting of three parts with inlaid Charnier joints (labelled c in “Fig. 2” of Fig. 11.2) which was held closed by a strong spring (labelled f). The socket was lined with rubber (labelled d) that surrounded the neck of the tooth and two-thirds of the root the rest of which projected into a hollow cavity (labelled e). This arrangement allowed a tooth to be properly positioned even if the root was abnormally long [11].
Fig. 11.2
Illustration of dental phantom from 1878. “Fig. 1” shows the head of the simulator on the stand and “Fig. 2” shows detail of the way the teeth were held in the jaw [36]
An article by George Cunningham (1852–1919) in the Dental Record in 1898 reported that Julius Weiss of Vienna had introduced a skull-based dental phantom known as the “Wiener Instituts Modell ” many years ago [8]. This simulator could be attached to a table or a dental chair (see Fig. 11.3) and the amount of mouth opening could be adjusted [12].
Fig. 11.3
The “Wiener Instituts Modell” by Julius Weiss. The position of the skull is changed by moving the rod (aa) and tightening the clamp. The jaw is hinged (c) and tightening the screw (b) holds the mouth open [12]
The wooden head used by wig maker’s was developed as a substitute for an actual skull (see Fig. 11.4). Cunningham noted it made a good practical as well as serviceable “dummy patient” but all the arrangements for fixing teeth that he had seen were clumsy and whilst they were reasonable to practice fillings they took too much time and labor for the frequent renewal required when practising extractions [8].
Fig. 11.4
Dental phantom based on a “wig maker’s block”. (Credit: Zahnmuseum Wien)
Using Simulation to Teach Technique
The Manual of Operative Technics—A Practical Treatise on the Elements of Operative Dentistry by Thomas E Weeks of the College of Dentistry at the University of Minnesota, first published in 1891, provided a step-by-step simulation-based training program.
The extreme difficulty of preparing typical cavities in dried teeth, makes it desirable to limit such cavity preparation in the teeth mounted in the articulator. Only one cavity of each division of the several classes need be required. In order that the student may have the necessary practice in cavity preparation, some material should be chosen which can be cut more easily than the dry teeth. Dice,2 and toothbrush handles of bone are employed, but the coarseness of the grain in the bone, makes it difficult to get nice cavity margins. Experiments with celluloid have progressed so far as to indicate that this material may be so prepared as to meet the requirements. It may be easily moulded into tooth form, which will be a great advantage. Having selected some material, cavities should be prepared in it before attempting to prepare any in the teeth. [13, pp. 63–64]
An advantage of preparing cavities to receive an inlay or plastic filling material on a toothbrush handle was that it offered plane and convex surfaces [13, pp. 53–56]. A “rubber tooth form for use in operative technics” (see Fig. 11.5) used in later exercises had a concave base and that was used to prepare cavities for a concave surface [13, pp. 92–93] The teeth in the “tooth form” (see Fig. 11.5) were deliberately placed far apart for easy access to all surfaces. However, this meant the student could only practice “contour for form”. Teeth in a “dummy articulator” (see Fig. 11.6) were recommended for practice in “contour for contact” and the preservation of the interproximate space when filling cavities with plastics.
Fig. 11.6
Articulator with teeth embedded in plaster of Paris. In this model some material has been removed to expose the roots for demonstration [26]
Before students begin their practical exercises the teacher should demonstrate each operation. The cavities, which were prepared in the large clay models with enlarged copies in brass of the instruments which the students used in cavity preparation, may now be filled; use enlarged pluggers of brass, with colored cotton rolls to represent cylinders of tin or gold, and ropes and ribbons of sheet wadding (cotton) to represent ropes and ribbons of tin or gold, soft clay of another color, or putty may be used to demonstrate the use of plastics.” [13, pp. 92–93]
Fergus and the “First” Dental Phantom
“The object of it was to aid students in acquiring practical skill in dental operations prior to their undertaking the treatment of patients, and also to facilitate the work of teachers.” Fergus (1898) [7]
Edward Oswald Fergus (1861–1946), presented a dental phantom he had designed at several meetings in 1894 and it featured in dental publications in English and German (see Fig. 11.7). An innovative feature of this simulator was how it was designed to be used in place of the head piece of a dental chair. At a British Dental Association meeting in Newcastle-upon-Tyne in March 1894 Fergus demonstrated how this was achieved and how the teeth were mounted and then proceeded to demonstrate several operations on the simulator [14].
“Mr. Oswald Fergus, Glasgow, exhibited and demonstrated upon a “dental phantom,” recently devised by him for the aid of teachers and students, on which any dental operation may be performed out of the mouth, the surroundings being to the operator those of daily practice.”
“Almost any operation on the human mouth might be demonstrated with the appliance. There was, in addition, an elastic band which went round both jaws, forming an artificial cheek, so that the student had to deal with conditions very closely resembling those that would be met with in actual life.”Stay updated, free articles. Join our Telegram channel
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