DEVELOPING OF THE SURFACE MODELL OF HUMAN GUMS 
Dr Käroly Fekete 
Department of Photogrammetry, University of Budapest, Hungary 
KEY WORDS: Close Range, Biometrics, Digital, Non-metric 
ABSTRACT: 
Our publication discusses a special task namely the photogrammetric possibilities of working 
out of the surface modell of the human gums. Besides solvability our experiments embrace 
also accuracy investigations. The instruments used were: non-metric camera, digital camera 
and digitalized photos. Needed control data were supplied by a test-field built for this special 
purpose. 
1. INTRODUCTION 
The Department of Photogrammetry of 
the University of Budapest has been 
asked to do an assıgned task that of 
making a surface modell of the human 
gums. This surface modell was 
necessary for the planning of a dental 
bridge of a dental prothesis by finite 
elements method. According to the 
judgement of the employer the durability 
of a denture planned and executed in this 
way will be longer. The reason for this 
is that the projector can take into 
consideration the appearing physical 
strengths when he puts the dental bridge 
into shape; it will be thicker where 
physical strengths will have a greater 
effect. 
The task -in the first place for medical 
reasons- implies also certain accuracy 
conditions. It is a demand on the 
evolved system the easy teachability of 
the persons without any preliminary 
studies of photogrammetry. This paper 
is a report of the first part of the task, an 
investigation of its photogrammetric 
accomplishment adhering to the limit of 
error. We intended not to restraint the 
possibilities of the switch over to the 
industrial production, for we have given 
a lot of kinds of possible solutions (i.g. 
160 
non-metric camera, still video camera, 
non-metric camera with a digital 
cameraback, posteriorly digitalized non- 
metric photographs) and also making 
known their various characteristics. The 
definite assembling of the joint- 
instrument will only take place after the 
observation of the employer on the 
experimental products. 
2. PLANNING PROBLEMS 
When solving the task we used the well- 
known methods of close-range 
photogrammetry. The photographs were 
not taken of the real object but of a hard 
plaster cast. These objects are produced 
irrespective of the photogrammetric 
solving. In every case these plaster casts 
were put into a test-field of control 
points and thus there were taken 
photographs of them. We applied two 
different kinds of test-fields: 1. was built 
preciselly of three rectangular spindles 
on which there were stressed some 
millimeter-paper and on this area there 
were unrestricted numbers of control 
points for processing; 2. a test-field 
reminding the control points of X-ray 
photogrammetry of higher accuracy but 
of less amount. Figures l/a and l/b 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B5. Vienna 1996 
show the 
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