language switch

A consideration of how we must do it in order to one day be able to use cad assisted by artificial intelligence.


Please note

You may feel some discomfort with the way the following sentences are expressed, but that is because they are one step short of becoming science.

Can a dental technologist mention things that only a dentist is supposed to be able to talk about, such as where the centric occlusion should be and things related to the centric relation?

I believe that when manipulating biologic bodies, the dentist should be in charge of any specialty issues related to them. I also think that when manipulating CAD for requirements that are not related to medical treatment or diagnosis, the dental technologist can, to a certain extent, request the dentist for the choice of settings in his/her opinion.

We can talk about this system when we use CAD to create prosthetics. From the standpoint of a dental technologist, I believe that in this way we can propose ideas and move forward in solving problems, if not solving the problems we are currently facing with regard to the fabrication of prosthetics.

# The centric occlusion is the relationship between the upper and lower dental arches. The centric relation is the so-called bone-to-bone positional relationship regarding the position of the mandibular fossa on the lateral side of the maxilla and the mandibular head on the mandible. The definition of centric relation has changed historically.

# Terminal hinge axis and central relation. Centric relation in the terminal hinge position of the mandible , in which the hinge axis is constant to both the mandible and maxilla.) This is taken from “Rethinking the Central Position (Theory),” which is featured in the July 2022 issue of “Shikai Tenbo”.

# “Shikai Tenbo” is a Japanese dental trade magazine. It is packed with tips, useful information, and columns for solving everyday problems, from clinical practice to clinic management!

For cases with large dental prosthetics, such as those involving the upper and lower jaws: The determination of the central occlusal position or central position is done by the dentist, since it is a diagnostic matter.

The shape of the occlusal surfaces of prosthetic molars is nowadays mostly created by dental technologists. However, I believe that if possible, it is better for the dentist to do the design. The reason for this is that the dental technologist cannot get out on his own from doing repetitively what he was first taught. The only thing they can do is to shape up their skills and shorten their fabrication time.

This is so because dental technologists do not have direct contact with patients. There is also the fact that it is for reasons of professional authority. Patients come to the office relying on the dentist and not the dental technologist. It is about authority and responsibility. Also, when reporting a case in an academic presentation, it is more interesting to the audience to say that the dentist designed the case and asked the dental technologist to produce it.

In the case of dentists, I believe that they can interactively change prosthetics by engaging with the living body, the patient. Nowadays, dentists rarely make prosthetics directly, so I think it would be better if dentists design prosthetics with CAD and dental technologists do the fabrication. So, what should be done in the dental care industry to achieve this kind of “new manufacturing”?

One of the system theories that is currently attracting attention is “autopoiesis”. If this autopoiesis can actually be introduced into dental prosthetics and prosthetic manufacturing in the field of prosthodontics, we believe that “new manufacturing” can be realized. I believe that autopoiesis will be realized when dentists actively participate in the design of prosthetics with a CAD-based system.

It may be difficult for dentists to freely use CAD without financial burden. Also, until now, it has not been customary for dentists to design specific prosthetics and for dental technologists to fabricate them. In the dental field, it is essentially the dentist who is responsible for both the treatment and the fabrication of prosthetics. Therefore, there is no problem for dentists to design with CAD from the viewpoint of the Dental Practitioners Act and the Dental Technologists Act.

Is there anything preventing “new manufacturing”? If so, is it the practice for dental technologists to design specific prosthetics? As for the use of CAD by dentists, there are now various forms of CAD licenses, which I believe have reduced the financial burden.

Before the advent of CAD, it was not possible to specifically design organic three-dimensional shapes such as teeth. We had no choice but to follow the style of designing while building.

In the general industrial world, 2D drafting systems appeared in the 1960s, and 3D CAD systems were commercialized in the 1980s. The first dental CAD system is considered to have been the “CEREC System”, which was developed and introduced in 1985 by a group at the University of Zurich, Switzerland, in collaboration with Siemens AG, Germany.

With some technical impetus, it would be possible to return the current situation where the dental technologist is designing the specific design of the prosthesis to its ideal form. The ideal form would be for the dentist to design the prosthesis and the dental technologist to fabricate it accordingly. Or it could be that the dental technologist creates the design when complete and the dentist checks it before fabricating it. The “optimization” operation that autopoiesis refers to would be a difficult operation for a dental technologist who has no contact with the patient.

The profession of dental technologist started when dentists became too busy with treatment, so they entrusted the fabrication of prosthetics for dental treatment to assistants who did not have sufficient knowledge of diagnosis and treatment, but only limited themselves to the scope of dental technology. Later, it became an independent profession.

However, since dental technologists do not have direct contact with patients, they are unable to evaluate the prosthetics placed in the mouth. For this reason, I would argue that dentists should be directly involved in the specific design of prosthetics.

It will be necessary to explain the rationale for the participation of the dentist in the specific design of the prosthesis. I propose the introduction of the “reduction of complexity” or the “concept of autopoiesis” for handling the oral cavity as a system. The “reduction of complexity” can be described as a procedure to make the system easier to deal with.

When human beings try to interact with nature in a new way, there must be some kind of orderly procedure, and it is not just a matter of being able to do it. Autopoiesis” is the procedure for this.

What is autopoiesis, a component of the dynamical system?

In the 1960s, the concept of autopoiesis, the basic model for a new system of autopoiesis, was introduced by two Chilean biologists and neurophysiologists, Humberto Augusto Maturana Romesín and Francisco Javier Varela Garcia. The artificial word autopoiesis, synthesized from the Greek words autos (= self) and poiein (= to make), means something like self-production. They describe this concept as an approach that appeals only to physical and chemical laws of nature, without the aid of supernatural forces or principles.

Autopoiesis was conceived as a concept to solve the mysteries of living systems, especially the immune system. How is it possible for life to utilize “non-self” and self-organize while still maintaining “self” as a system inside and outside the environment? It is thought that there is a mechanism of “self-reference to reproduce the self” and “self-recursion by the self.”

It is possible that life, while “self-reference” itself, has the ability to transcend the self-contradictions (conflicts) that arise in the process of self-referencing. Maturana and Varela hypothesized that this could be called autopoiesis. Their attempt is to use the concept of autopoiesis to formulate a general organizational principle for living things, one that is valid for all living organisms. Niklas Luhmann also created the social systems theory based on autopoiesis. The systems theory discussed here is based on Niklas Luhmann’s theory of social systems.

What is a complex system?

Niklas Luhmann always viewed the world and society as complex systems. He continued to seek for “meaning” as the fundamental unit that forms the world and society, and he regarded everything that processes and edits meaning as a “system.”

Luhmann saw society as a complex system, and that system is constituted by the meanings that humans understand. The science of complex systems is a new approach to science that studies how parts relate to the behavior of the system as a whole, how the system relates to each other and to the environment to which it belongs.

It is useful to approach the problem from two aspects. Consider, for example, the masticatory movements of the mandibular movement. The aspect from the natural sciences deals with the shape of the occlusal plane, which is the form of the teeth of the entity, while the aspect from the social sciences deals with the changes in the interocclusal space.

The “interocclusal space” is the place of communication between the upper and lower teeth. Simulation is one of the effective techniques in the science of complex systems, which includes design by changing parameters in CAD and coupled analysis of structure and motion using the finite element method.

The function of the teeth as a system cannot be found from the shape of a single tooth alone, and the shape of the occlusal surfaces of the molars cannot be understood without considering the communication created by the act of masticatory movement. The occlusal surfaces of the maxillary and mandibular molars are not only questioned in terms of their contact relationship in the centric occlusion position, but also in terms of the change in proximity relationship mandibular movement. The change in interocclusal space refers to the change in the gap between the upper and lower jaw teeth when the mandible is in motion to chew food. It is the same as a change in proximal relationship.

Complexity, such as in social systems, is resolved by systems theory, which brings exquisite complexity reduction or liberation from internal conflict. The more complex the subject matter, the more complex the system theory. Not only dentistry, but medicine in general is said to belong to the field of applied natural sciences. Medical care is also said to belong to the field of social science because it is organized by human beings. In other words, social systems theory distinguishes between the human world and the natural world, while at the same time integrating them to create a worldview based on the unique interpretation of human beings.

What is the relationship between autopoiesis and dental technology?

I believe that dentists should be actively involved in the specific design of prosthetics. To make this happen, we need a CAD system that can handle this and a concept for implementation. Autopoiesis is an appropriate concept for this. Rather than dental technology, we should expand the scope and introduce the concept of autopoiesis into the field of dental prosthodontics. This is beyond the scope of dental technologist, so I will limit my discussion here to the field of dental technology. I believe that the concept of autopoiesis can be introduced not only to the social systems of human society, but also to dental technology.

# The field of dental prosthodontics is the study of prosthodontics. Prosthodontics, one of the specialties of dentistry, is a branch of clinical dentistry that aims to restore the dysfunction and esthetics of the oral and maxillofacial system caused by the loss of teeth and related tissues. It is also referred to simply as prosthodontics. From Wikipedia.

When considering the shape of the occlusal surface of a prosthetic crown molar, this means that we must consider both the body of the tooth as a natural object and the occlusal surface space as a social object. In fact, it is the change in the gap/space between the upper and lower teeth that chews and bites through food, not the teeth as entities. No matter how fine the teeth are on only one side of the upper or lower jaw, they cannot perform their original function. I believe that “changes in the space between the occlusal surfaces of the molars caused by mandibular movement should be designed emergently.”

Unless the shape of the occlusal surfaces of the molars and the incisal edges of the premolars, which represent the function of the molars, are treated in a social scientific manner, it would be impossible to interpret the meaning of the shapes. The convexity and concavity of the occlusal surfaces of molars has a specific pattern depending on the site. Some molars have one root, some have two roots, and some have three roots, depending on the site of the molar. The roots of molars also have complex curvatures. I believe that the left-right joint of the mandible is also a complex system with a mixture of three-dimensional sliding and rotation, and is so complicated by various factors that it is difficult to model it into a simple system.

In order for the dentist to describe from the standpoint of the autopoiesis concept why the pattern of convexities and concavities of the occlusal surfaces of the molars that function during masticatory movements are shaped in this way, it is necessary to accurately measure the internal structure and shape. It will also be necessary to analyze the exact movement of the mandible. Furthermore, it would be necessary to accurately measure how the interocclusal space of the upper and lower dentition changes as the mandible moves.

Teeth are not created by humans. The “human jaw system as an entity” already exists. Therefore, the structure and shape of the actual jaw joints, teeth, and bones already exist as solid, rigid objects. This is analyzed in detail. Tooth enamel is a hard substance and is clearly delineated, but it gradually wears away over time.

The need to consider how the gap between the occlusal surfaces of the upper and lower jaw teeth changes is important because, although there was something unknown before occlusal wear, it cannot be treated without knowing what has changed over time. The gap between the occlusal surfaces of the teeth gradually changes over time. The treatment is to restore what has changed, and this emergent content may be a new target for treatment.

I believe that CAD design requires static and dynamic design for the same object. Static design is a blueprint in the usual sense. It includes the dimensions, position, and tilt of the teeth. The dynamic design is necessary to explain the static design, and it does not mean that two types of blueprints are needed. It is needed to design the “why of static design. Dynamic design is a four-dimensional design. Time is built into the design.

The words contingency and double contingency are confusing words. Can you describe them in other words?

Contingency can be translated as “possibility of another kind,” “functional equivalence,” or “contingency,” or it can be translated in various ways depending on the context. Contingency also has two semantic configurations. One is “dependent on something that is”. The other is “is otherwise possible”. In other words, contingency as “impossibility” and “negation of necessity. It seems that double contingency can be paraphrased as “double conditional dependence”.

What is a social system anyway?

What was the problem that Parsons was trying to solve in his book the “Social System”? It is the famous “Hobbes Problem”. The “Hobbes Problem” is the question of how social order is possible when people pursue their interests in a utilitarian manner. According to Parsons, Thomas Hobbes believed that this problem could be solved by a social contract between individuals. However, Parsons considered this to be an overextension of the concept of merit, which in fact has not been solved. In the “Social System”, the “Hobbesian problem” is replaced by the problem of double contingency.

The “double contingency” means that the fulfillment of the needs of the self and the other depends on the actions of the other, but that the actions of the other depend on the actions of the self and the other. Thus, the problem of social order is transferred to the problem of the stability conditions of mutual action in a bilateral relationship. In other words, the social system is used to stabilize and maintain the self and the other party. This is a description of the system of human society, but I think it can also be applied to natural things in other words. In the end, it is a matter of human beings themselves. It is a matter of how human beings perceive themselves.

The “structural coupling” of autopoiesis

Let us now apply the “structural coupling” of the autopoiesis theory to the case of reconstructing the shape of the occlusal surfaces of the molars. Each maxillary or mandibular dentition remains within a closed system of its own value system, and if it is beneficial to improve the functionality of its own system, it can be shaped to establish a reciprocal relationship with the dentition of the other jaw.

Interpenetration, on the other hand, refers to the phenomenon that occurs when two different systems, i.e., the maxillary and mandibular dentition, are interrelated, thereby increasing the complexity of the meshing of their respective occlusal surfaces. According to Luhmann, the key to interpenetration is that the two systems are open to each other, allowing the complexity of each system to be transferred to the other. Through this interpenetration, the two systems have the opportunity to transform each other. The occlusal surfaces of the maxillary and mandibular dentition systems are open rather than closed, exchanging the complexity of the opposing system for the complexity of their own system. This is what we might describe as interpenetrating.

Even if humans understand how the natural world works, they cannot do the same things that the natural world does. There may be things that cannot be done without relying on the human imagination. With regard to the generation of tooth shape, it may be genetically determined in the natural world, but if a human reconstructs a part of it, it cannot be created by genetic manipulation.

The goal will be achieved by using reverse engineering thinking to reconstruct the resultant existence that would have taken place in the natural world. This method is called the autopoiesis method of reconstructing tooth shape. While the traditional method involves manual editing of tooth shape based on human imagination, the new method uses artificial intelligence to play the role of communication between the upper and lower dentition and the two systems, and CAD to create the auxiliary shapes.

Necessity and Coincidence

To change what is at work inside the object to the categories of uniqueness and diversity, rather than the categories of necessity and chance, is to trust and bifurcate the spontaneous sensibility of man. By perceiving the object from these two perspectives, it may be defined as being “optimized”. What would change by changing the way we dualize in this way?

Let us first consider necessity and contingency. I will discuss uniqueness and diversity later. The categories of necessity and contingency were also created by man. This is an important view in materialism. Where is the perspective that can be seen in the combination of these two? And what is the difference between the newly proposed categories of uniqueness and diversity? The former sees only the past and not the future, leaving the future to come from the other side. The latter believes that we must look at both the past and the future and actively engage with both.

The theory of evolution was created by analyzing what would have happened in the past based on physical evidence. The cutting edge is the present. There is no further to go. What is evolution trying to explain? It is the present, and the natural world, including us humans, as we exist in the present. It is the process by which we have come to be the way we are today. Evolutionary theory explains that our world as it exists today exists for this reason. The future cannot be analyzed because there is no concrete data. It is unknown. It is natural. If there is one, it is the hope of humans to exist in the future.

Materialism has divided the past into two parts. I said it divided the past into two parts, but actually it did not divide the past into two parts. In fact, the past cannot be divided into two parts, such as inevitability and contingency. This is possible only because the outcome is known. The present is something that has already been determined. It cannot be applied to the future. It is a human evaluation of something that has already been determined. No matter what evaluation we give to the past, the present in the material sense remains unchanged.

Inevitability is the certainty that it will happen, that it cannot be otherwise, and that we know when it will happen. Coincidence is the element or property that makes the unexpected happen. Coincidence changes the present, but we do not know how. It also means that we do not know when it will change. There are causes that cause certain things to happen and causes that cause uncertain things to happen, and the world has been established by the combination of these two.

In this category, the future is 100% coincidental, meaning that it is uncertain. Inevitability can only be found in what has been experienced in the past. The future does not yet exist and should not be spoken of lightly by humans. And the future, as such, is not subject to concrete analysis by humans. The passage of time in one direction explains what makes the present and the reason for the existence of the present, which explains man’s passive position in relation to nature. There is no vision for the future.

The categories of necessity and chance revolve around the perception of opposites. Inevitability and contingency are a choice between two opposites. They are relative, such as “what we know” and “what we don’t know,” or “what is clear” and “what is blurred.” This is the human mind, and the conflicting minds within us have come up with this division in an attempt to solve existing problems. This is a way of explaining the present in terms of these opposing relationships.

We cannot find certainty by looking into the future from the present. Certainty can only be found in the past. Everything we can see today was produced in the past. Looking only at the past is called thinking in terms of the categories of necessity and coincidence. The categories of necessity and coincidence are tools for recognizing the past. The past cannot be separated because the relationship is fixed. The cause-and-effect relationship between things is fixed, but we just cannot know everything.

I believe that the categories of necessity and chance that support evolutionary theory can be rephrased as a mixed bag. The division into two categories, necessity and chance, is merely rhetoric. In fact, it represents a state of affairs in which the two are indivisible. The category of inevitability and contingency encourages us to adopt such an attitude toward the future.

Uniqueness and Diversity

What is the only thing that matters to human beings? I believe it is the eternity of the human world. There is nothing else for human beings. Diversity refers to the ratio of choices between two things. By diversity, I mean a ratio of 10,000 to 1, or 100,000 to 1, or more. In any case, it means that the other person has only one choice, but I have an overwhelming number of choices in relation to it. I think we should take pride in the fact that we are special in the natural world.

Science, by the way, is useful, and I believe it is the field in which humans are currently focusing most of their efforts. Science is a tool for man’s active involvement in the future, and was created to project the achievements of the past into the future. The future does not yet exist. Is the future something that should be left to nature through “necessity and chance,” or is it something that will be created automatically? Or is it something that must be created by human beings? It seems that the materials for creating the future have been prepared from the past to the present. Is there anything in particular that humans should do about the future? I think that what is certain about the future is that it is human. As long as human beings can think about the future, there is a future. Only human beings can think about the future. To think about the future, we need two basic categories: uniqueness and diversity.

One is the eternity of the human world, and the other is the recognition that humans are in many ways diverse and overwhelming in the natural world. These are things that must be fulfilled with human responsibility. Without a sense of responsibility, it is impossible. The categories of uniqueness and diversity have a common perception of match. Without the unity of these two concepts, man cannot exist in the future. It is not harmony or unity.

How should we treat history when we consider it in the category of “uniqueness and diversity” that I have proposed here? I believe that history is a record of reality based on evidence and facts that we can refer to when we think and perceive, and that it is a description of one possibility that seems reasonable among all the possibilities that could be generated. This is a very subjective view. The subject of the choice is the human being, who selects one possibility from all possibilities and describes the best one as a fact, and that is what history is.

Therefore, future history is a description of a direction more advanced in time than the present, and therefore has not yet occurred in reality. It is human beings who create the path from the described future and present. To think in the category of “uniqueness and diversity” is to be convinced that it is man himself who will protect the future of mankind, and that it is man who sustains this world.

If we consider history in the categories of inevitability and coincidence, how should we treat it? Even if we use objective expressions, the subject is definitely a human being. This is the traditional view of history. I think evolutionary theory is included in this. Uniqueness and diversity” and “necessity and chance” are different categories. Naturally, the two are expressed differently. Past history is what has been chosen and how it has been chosen and described by objective human judgment.

What I am trying to say here is that if we think in the category of uniqueness and diversity, we are free to create our future. Also, when it comes to the past, we cannot physically manipulate the past, but we can change our evaluation of the past. By changing the category from “inevitability and chance” to “uniqueness and diversity,” we can find more things in the past that are important for the future of human beings, and we can divert them to the future.

We do not know whether monkeys gradually evolved into humans or whether smooth-skinned humans appeared out of nowhere, but humans appeared in this world before we knew it. A baby grows up and becomes a child, and before long, it has a mind that understands about the world. Just as it is difficult for human beings to recall their early childhood in their own memories, it is difficult for human beings to know the beginning of human history. Since there are no records, the only way to know this is through our imagination. Moreover, as long as we look to the future in the categories of inevitability and coincidence, we will only reproduce the past and will not move forward in the slightest.

The Importance of Social Science

When we look at the structure of the human jaw joints, the overall shape of the upper and lower teeth, and the pattern of the occlusal surfaces of the molars, we see a situation in which they function. Their function and form are consistent, and no contradiction or conflict can be found. When we look at biting and articulating food, we see a situation in which the parts of the oral cavity are matched to their purpose and each performs a specific function. We can find in this situation a system of perception and knowledge as a social scientific community that cannot be reached only from the natural sciences.

This is why we also look to the social sciences. It is because it is what humans observe and think about. Humans cannot escape the ties of being human. Even if something is not created by humans, if the observer is human, it becomes a fact through the filter of humans. No matter how you do it, you cannot remove the human filter. Even if it could be removed, it would be something that humans could not understand. It would be a meaningless enumeration. Human beings can only be perceived as meanings and values that we can understand.

Although humans are part of the natural world and independent beings, until now humans have found and used everything from nature. The only thing humans can really create is logic (theory). As for things, we use 100% of what is found in nature. However, even this may be called a discovery rather than a creation. Ways of expressing reason (theory) include philosophy and mathematics. These are human inventions. However, we cannot add human-invented rules to the natural world. All we can do is engage the rules of nature. All that man can do is to use the forces and mechanisms of nature.

In the natural world, the only thing that humans alone have had is the “human filter.” The “human filter” is the data you refer to in your head. We have seen, heard, and thought through this filter. Because we have this filter, we have been able to flourish as we do today. It is the recognition of the eternity of the human world and the fact that humans are in many ways the dominant force in the natural world, and we have thought about the future. This is why we need the social sciences as well as the natural sciences.

Continue to Dental Text 2