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ABSTRACT: To test the validation of the 3D measuring technique.
A life-size plaster cast of human head was used as the anthropomorphic model. Fifteen experimental conditions were studied. Nine linear distances between landmarks and Nasion were measured each time. These were compared to the standard anthropometric measurements using the same landmarks.
The mean difference was 1.21mm (2.09%). Among the 8 conditions imitating different head posture,only the one turning 10 degrees to the left had a significant difference from the normal position.
In accordance with the requirements of " human measurement handbook", the system error is acceptable.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 07/2001; 10(2):159-61.
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ABSTRACT: The purpose of this article were to assess the reproducibility of the landmark locating, and to obtain some facial soft tissue measurements data of the teenagers.
8 males were selected to refix the black markers by the same operator and remeasure 14 items by the system, then compare both results. Three dimensional facial morphametry was investigated in a sample of 20 teenagers at the early stage of the permanent dentition.
No item of the remeasurement test showed statistical difference error. The sexual dimorphism was found in the measurements connecting with lower face height(Sn-Pg).
It indicated that the landmarks selected in this study had biologic significance and unique definition. The result of teenager facial measurements is in accordance with growth rule.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 07/2001; 10(2):162-5.
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ABSTRACT: To combine measurement and image technology as an objective means to help prosthodontists provide better service.
The system was developed by consisting of two CCD cameras, real time hardware for the recognition of markers and software for the 3D reconstruction.
It allowed efficient, direct and noninvasive calculation of the 3D liner and angular measurements of the human face.
This system is a useful way to get 3D information of the human face. It will be a good supplement to the classic cephalometric analyses.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 07/2001; 10(2):157-8, 169.
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Shanghai kou qiang yi xue = Shanghai journal of stomatology 04/1999; 8(1):53-5.
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ABSTRACT: OBJECTIVE:This article introduced a concept of dynamic image measurement for calculate the quantity of cirumoral soft tissue movements. METHODS: A developed computer image analyzing system was used to calculate the quantity of circumoral soft tissue movement under the three conditions. RESULTS: (1)When/mo/is pronounced,lip protrudes,the upper lip landmarks move upwards,imwards and forwards,and the lower lip landmarks downwards and backwards.The variation of upper lip triangular area will be M2<M3<M1,that of the lower lip will be M3>M2>M1. (2)When/si/is pronounced,as a result of vowel,the amount of lower lip moving down backwards is more than that when/mo/is pronounced,which makes the lower lip triangular area comes to be M3>M2>M1. CONCLUSION: Pronunciation is one of the important oral functins. It could be used as a method of research to measure the facial soft tissue change dynamically and effectively.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 12/1998; 7(4):197-9.
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ABSTRACT: The rehabilitation of vertical dimension of occlusion(VDO) exactly is one of the most important procedure for dental prosthesis in the field of prosthodontics.In this study,total of 19 subjects with normal range occlusion were selected.We measured 33 parameters relating to VDO of their facial soft tissue at intercusping position,with the technique of digital imaging analysis.The results as follows:we established a set of normal values of facial soft tissue parameters,which is suitable for the age group of 21-24 years old.It would provide an objective criterion for the rehabilitation of VDO.Also the normal values in this studies had been compared with other other studies,and it showed that the values of some parameters in our study,such as CH-CH',nasolabial angle were very close to oter data.Furthermore,it was found that both the position of the upper lip and the lower lip of the subjects were more anterior to that of white men,while the degrees of nasolabial and labiomental convexity were less obvious.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 01/1998; 6(4):219-21.
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ABSTRACT: Soft tissue shape is an important parameter to evaluate the postprosthetic effect of facial profile.In this study,the technique of digital imaging analysis was used to transferring from imaging informations to digital information,and then these information were imputed to computer for capturing,measuring and analyzing.So far,a set of digital imaging analysis system relating to the speciality of prosthodontics has been established preliminarily,with the advantage of quantitative analysis,non invasion and accuracy.It will provide a new way for reconstructing vertical dimension of occlusion.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 01/1998; 6(4):216-8.
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ABSTRACT: In this study,33 parameters relating to vertical dimension of occlusion(VDO) of 19 subjects' maxilofacial soft tissue of four different vertical dimentsions(VDs) were measured.All of them were in intercusping position,with the technique of digital imaging analysis.The findings as follows:(1)A set of normal values of facial soft tissue's parameters of four different VDs was established,which was suitable for the age group of 21-24 years old.(2)When the VD was raised to the certain height(H4),it would affect the size of angle of the inferior soft tissue of lip distinctly,furthermore,the correlation analysis showed that there was a positive correlation between the variance of VDs would arouse the change of the inferior soft tissues of lip,especially its size of angle,is very correspondingly and obviously.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 01/1998; 6(4):222-5.
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ABSTRACT: In this study the artificial palates made of black vinyl seat covering the palate and occlusal surfaces of maxillary teeth were coated with white alginate powder and inserted into the mouth of the subjects.After pronunciation of the test sounds,the tongue contact areas on artificial palate were demonstrated by wetting of powder and changing in color from white to black.Thus,photographnys of palatograms were taken.After taking 5 palatogram of each sound,the samples were averaged by an image processor.The averaged outline of each subject's palatogram was converted into a standarized dental arch form,with the gray scale of each image reversed and reduced,and then added to every pattern of the same sound produced by all subjects.Thus,palatograms were based on the frequency of over lapping.From this compiling, contact areas that were common in more than four out of six subjects were extracted.
Shanghai kou qiang yi xue = Shanghai journal of stomatology 01/1996; 4(4):204-6.
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ABSTRACT: In this study we established a computer bases on Speech Signal Processing System and changes of formant frequencies of the vowel/i/accompany the changes in the oral cavity after maxillary surgery and prosthodontic reconstruction.The study found the F1 for vowel/i/has no change,while the F2 peak significantly shifted between the preprosthetic and postprosthetic speaking condition after anterior resection of relative energy error value and the speech intelligible measured aurally(P<0.05).
Shanghai kou qiang yi xue = Shanghai journal of stomatology 07/1995; 4(2):85-6.
