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This paper aims to describe how a novel biomimetic chewing robot was designed, including its motion, force, control and mechanical designs, and shows some initial experiments about motion tracking.

According to the biomechanics, the authors modeled the muscles of mastication in six linkages and the temporomandibular joint in higher kinematic pairs of point contact. As a result, the chewing robot was represented in a redundantly actuated parallel mechanism. With reference to literature data on the biological system, the authors specified the motion and force requirements for the robot via inverse kinematics and force analysis. A prototype of the robot was built, which has a position control system and is driven by six linear actuators. Experiments were conducted to show the capability of the robot in reproducing the human chewing motion.

A chewing robot was successfully modeled and developed, which is able to simulate the motion of human mastication in a biologically faithful way.

The chewing robot as a scientific instrument can be used to test dental materials and evaluate food textural properties of chewing.

Two higher kinematic pairs of point contact are proposed to simulate the two temporomandibular joints. The mechanism of the novel chewing robot is the first of this kind, which has two higher kinematic pairs of point contact and is a redundantly actuated spatial parallel mechanism.

This paper aims to verify the workspace and movement performance of a redundantly actuated humanoid chewing robot.

A redundantly actuated humanoid chewing robot with 6-PUS linkages and two higher kinematic pairs (HKPs) is introduced. The design of HKPs is specified by mimicking the temporomandibular joint (TMJ) structure obtained through a computed tomography scan of the mastication system. The border movement, mouth-opening trajectory and velocity of subjects’ lower incisor point are measured by using the mandibular kinesiograph. Based on the kinematics, the envelope of the workspace is analyzed. The workspace and mouth-opening movement experiments are carried out. The border movement of the lower incisor point is measured. The mouth-opening trajectory is planned and tested on the chewing robot.

Comparing with measurement results of border movement and mouth-opening movement of human, it is shown that the humanoid chewing robot can meet the workspace requirements and is able to perform mouth-opening movement like human-beings.

The chewing robot is designed to reproduce human jaw movements and application in test of dental components and materials or evaluation of food textural properties.

The chewing robot is inspired by the mastication system which itself is mechanically redundant because of the TMJ and more muscles than required. The novel spatial redundantly actuated chewing robot is the first of this kind with two HKPs to mimic the human TMJ and is a higher fidelity mechanism.

The successful application of robots in surgery and other medical fields prompts us that robots can also play an important role in oral restoration. The traditional way of complete denture manufacturing is manual and only high‐level dentists and skilled technicians can do this work well. But we believe that a robot can do this work better and more easily. Artificial teeth are very complicated in shape, and not easy to be grasped and manipulated accurately by a robot gripper. Aiming at improving our previous robot manufacturing system of complete dentures, we present a new method to perform teeth implanting. We improve the previous manufacturing procedure by adding several components in the operating process. By this method, the robot gripper only needs to grasp and implant intermediate blocks, which have very simple shapes and are easy to handle precisely. The 3D human‐machine tooth arrangement software performs the calculation of intermediate blocks’ positions and orientations. We perform the experiment of tooth arrangement for a patient, and obtain a pair of ideal tooth arches. A complete denture can be manufactured according to this result.

An accident of architecture has placed Pisa upon the tourist map along with such evocative names as Rome, Florence, Galileo and Fibonacii, to say nothing of Buozzi and Giovanni. As the venue for the 5th International Conference on Advanced Robotics, ICAR, Pisa has an atmosphere that is as far removed from sensor fusion and mobile robotics, as Los Angeles is from Italian Renaissance art. Yet this contrast serves only to emphasise the technological steps made, and being made, in many areas of robotics.

3D printing techniques have been widely used for manufacturing complex parts for various dental applications. For achieving suitable mechanical strength, post-cure processing is necessary, where the relative time duration and temperature specification also needs to be defined. The purpose of this study/paper is to assess the effects of post curing conditions and mechanical properties of 3D printed clear dental aligners

Dental long-term clear resin material has been used for 3D printing of dental aligners using a Formlabs 3D printer for direct usage on patients. Post-curing conditions have been varied, all of which have been subjected to mechanical compression loading of 1,000 N to evaluate the curing effects on the mechanical strength of the aligners.

The experimental studies provide significant insight into both temperatures and time durations that could provide sufficient compressive mechanical strength to the 3D printed clear dental aligners. It was observed that uncured aligners deformed plastically with large deformations under the loading conditions, whereas aligners cured between 400°C–800°C for 15–20 min deformed elastically before fragmenting into pieces after safely sustaining higher compressive loads between 495 N and 666 N. The compressive modulus ratio for cured aligners ranged between 4.46 and 5.90 as compared to uncured aligners. For shorter cure time durations and lower temperature conditions, an appropriate elevated compressive strength was also achieved.

Based on initial assessments by dental surgeons, suitable customised clear aligners can be designed, printed and cured to the desired levels based on patient’s requirements. This could result in time, energy and unit production cost savings, which ultimately would help to alleviate the financial burden placed on both the health service and their patients.

It is not an easy and simple task to manufacture a complete denture with high quality. Traditionally, it often needs a medical expert with experience and hand‐on skill, due to the manual way of denture manufacturing. The purpose of this paper is to implement the multi‐manipulator tooth‐arrangement robot system that can fully automate the denture manufacturing process.

A novel complete denture manufacturing mechanism is designed, which is based on the multi‐manipulator and dental arch generator. The visual tooth‐arrangement and robot control software is developed in VC++6.0. Preliminary experiments on tooth‐arrangement have been conducted using the proposed multi‐manipulator tooth‐arrangement robot prototype system.

The multi‐manipulator tooth‐arrangement robot prototype system can automatically design and manufacture a set of complete denture that fit a patient by visual tooth‐arrangement and robot control software according to the patient's jaw arch parameters.

The implication of research is that it is feasible that the manufacture strategy of complete denture fulfilled by multi‐manipulator tooth‐arrangement robot. The limitation of research is that it is difficult to realize coordinate control.

The traditional manual method which makes complete denture by medical personal experience will be changed after the multi‐manipulator tooth‐arrangement robot system is manufactured, and adjustment to each tooth position and orientation will be realized by this system.

Diseases due to nutritional deficiencies might well be considered something from the poverty and grime of Victorian times and unknown to the people of this affluent society. It may come as a shock to many people, therefore, to learn that the rising incidence of rickets among the young in some of our big cities is causing grave concern; that iron deficiency anaemia, not altogether uncommon in women and in the undernourished but rarely of any great severity, is being found in a much more severe form in a great many West Indian infants, the hæmoglobin frequently not amounting to 50%; and that among the many skin lesions of coloured children there is at least the suggestion of riboflavin and perhaps other vitamin deficiencies. All this despite the blessings of the welfare state and a half‐century of local authority personal health services. It casts no reflection on these services, however; their work has resulted in vastly improved child health in this country, which speaks for itself.

The purpose of this paper is to provide a novel assembly simulation method to reduce the repetitive and tedious assembly simulation work. Currently, assembly simulation is always carried out by human–computer interaction, which is a time-consuming and tedious work. The most important reason for this problem is that the assembly simulation is a mapping between human intent and movements of models; at the same time, assembly information is transferred from semantic level to geometric level. However, some essential assembly information is lost during the transfer, and it must be accomplished through manual definition. To address the issue, a novel assembly simulation method is proposed in this paper based on semantics and geometric constraint.

First, an assembly operation semantic model is put forward to integrate and manage the semantic information of assembly, and some rules for modeling are generalized. Second, method for transferring assembly information from semantic level to geometric level is presented by dividing assembly operation into a set of simulation actions and providing some rules for this division. Then, a geometric constraint-based calculation method is proposed to obtain the essential parameters of each simulation action. Finally, cases are studied to demonstrate the effectiveness of the method.

Results show that laborious work would be reduced, and the redundant human participation would be avoided in assembly simulation.

It has the potential and possibility to change the current pattern of assembly simulation.

A novel assembly simulation method based on semantics and geometric constraint is presented to make assembly simulation more convenient and faster.

Implant surgery is generally accepted as the best technique for complete teeth replacement. However, it is also the most demanding technique to implement and the most onerous to the client. It would be helpful to reduce costs and simplify procedures in order that the general public could benefit from implant dentistry. This paper reports a robotic system developed with the objective of studying stress/strain distribution caused by implants inserted in blocks of a polymer. The polymer exhibits the same mechanical properties of the human mandible bone.

The system includes an industrial robot manipulator, a data acquisition board, strain gauges for stress/strain evaluation and a force/torque sensor (equipped with accelerometers) placed on the robot wrist. The objective is to optimize the number of implants and their placement/orientation, contributing in this way to reduce the overall cost of implant surgery. The system is presented in detail and explored for drilling and implant insertion.

The preliminary results are encouraging and indicate the usefulness of the system. The three presented situations correspond to general clinical procedures and, as can be concluded from the preliminary results, the intensity of the applied forces increase with the inclination of the drilling tool. Since, the depth of the holes is the same, it can be also concluded that the dissipated energy is superior in the 30° hole. Apart from inclination all the other properties remain constant during the force evaluation; therefore, we expected that during the perforation of the 30° hole the temperature should raise more than in the other types of holes. This aspect will be addressed in detail in the near future (just by carefully monitoring the temperature) because living tissues should not be submitted to temperatures greater than 42°C. The observed fluctuation in the modulus of the force during a drilling cycle suggests that the material is not homogeny. The results indicate that the strain is larger in the vertical load. This might be related with the fact that inclined applied forces imply a distribution of the strain/stress forces at least for two directions.

Further work will include more sensors to obtain all the data.

This will be of interest to the implant industry, since low prices will significantly increase the market and consequently the need for implant products. Currently, implant surgery as well as teeth replacements are based on a few general rules that, very often, do not take into account the specific needs of the patient. This happens independently of clinician expertise, which does not have enough biomechanical information to plan the number, location and orientation of implants in a specific surgery. Consequently, in most of the cases the needs are overestimated, to guarantee long‐term success, which implies expensive procedures and more discomfort for patients.

This work reports on a robotic system to simplify implant procedures.

When eating abroad, and conducting those operations necessary and incidental to the intake and mastication, and, one may hope, to the pleasurable enjoyment of such flesh, fish, fowl or other nutriment needed to sustain our strength, maintain our bodily vigour, or to pander to our base appetites, so difficult to resist, it is quite customary, and indeed, unfortunately often unavoidable, to perform these alimentary exercises to the accompaniment of some form of music, usually not too good of its kind, and often even worse than that. The connections between food (and drink) and music are many and various, continually appearing in history and in our literature; “ music … the food of love,” and again, “ There's sure no passion in the human soul but finds its food in music.”