CHAPTER 6 SIMULATION AND ANALYSIS
6.4 Comparisons
In last section, the final design is produced by the decision-matrix method. The QFD target which developed in section 4.2 is introduced to compare with the specifications of the final design to estimate the achievement. The QFD target is defined considerately in accordance with the patent analysis and market survey. The results of comparison are going to be an essential reference for the future works.
As the Table 6.4-1 shown, the specification of the final design is listed in the “Achieved”
row. The specification achieves several QFD targets which listed in the “QFD Target” row.
The adjustable range is less than the target, but larger than commercial product TAP-T. In the lateral mobility, the height of the inner wall of tray, and separate height of mechanism are better than the target. Those specifications provide the larger movable range, prevent the inappropriate touch with gums, and avoid the jaw opening exaggeratedly that all of them are referred to the comfort during using time. The contact area is referring to the area of the fixation portion on the tray. In the final design, the shape of fixation portion is just a preliminary design. It is required to be modified for obtaining the higher strength of fixation on the tray in the future. The large volume of the final design seems to be the drawbacks.
Maybe the tolerable volume of mechanism for patients can be tested by clinical experiments in the future. At the same time, the durable time of the device and time for adaptation by patient are required to be tested under real using situation.
Table 6.4-1 Comparison between the QFD target and the achieved target
Adjustable range (Front-rear) Adjustable range (Up-down) Pitch of adjustment Jaw rotate downwardly Lateral movability Tray Dentition-fitted tray Contact area Even contact Steps to adjust Height of the inner wall of tray
mm mm mm y/n mm y/n y/n mm2 y/n # mm
TAP-T 7 0 0 y 7.5 y y 55 y 1 9
QFD Target 3-8 0 0 y 8 y y 50 y 1 9
Achieved 3-7.5 0 0 y 9.8 y y 23.5 y 1 8
Table 6.4-1 Comparison between the QFD target and the achieved target (cond.)
Separate height of mechanism Time of using MAD Steps to wear Disengage mechanism Depth of mechanism Biocompatible material Steps to clean Time for adaptation # of componenets Durable time Maximum load
mm hr # y/n mm y/n # week # yr N
TAP-T 7 > 8 3 n 12 y 3 1 6 3 －
QFD Target 8 > 8 3 y 14 y 3 1 10 3 100
Achieved 6.3 － 3 y 16 y 3 － 12 － 100
CHAPTER 7
CONCLUSIONS AND FUTURE WORKS
7.1 Conclusions
Snoring is not only a very prevalent phenomenon during sleeping time but also an extremely prevalent disorder that influence the health of snorer. The obstruction of breathing leads to many symptoms in nocturnal and daytime that causes the variation of physical condition, the reduction of work efficiency, and even the happening of an accident. Therefore, the treatment of snoring is important. Based on the reviews of medical literatures, the MAD has been approved as an effective therapy for snoring and mild to moderate OSA. In this study, several new designs of the MAD are proposed and some conclusions can be made as follows:
1. The patent analyses and commercial products surveys assist the realization of the techniques and developments of the MAD which provide plenty information for consulting in the later procedures of design.
2. The QFD method is applied to clarify the customers’ requirements, the engineering specifications, the evaluation and specifications of commercial products, and then defines the target specifications for designing a competitive product.
3. In the conceptual design phase, four concepts are proposed in the end of the conceptual design procedure. Moreover, the disengagement function and a combination design which integrates adjustment and lateral movement functions are proposed.
4. The results of finite element analysis are translated into the design factors to be considered as an index of strength, and compared between each concept and one commercial product.
5. The concept 3 is evaluated as the best concept between all of the concepts by proceeding the decision-matrix method.
7.2 Future Works
About the future works of this study, some points can be described as below:
1. Search for the information about the grinding force in sleep bruxism to make the strength simulations more accurate and similar to the real loading situation.
2. Dimension optimization is recommended for the final design to reduce the size and to obtain the optimum strength.
3. The prototype of the final design can be manufactured after all of the dimensions are decided.
4. The clinical experiments are required to verify the efficacy of therapy by using the MAD of the final design.
5. Apply for the 510(k) notification from FDA before the product promoting to the market.
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