226
3 Holographic Interferometry for Studying …
deformations were observed in the alveolar area and the jaw joint in both planes. A
significant diminution of deformation was in the front area of the jaw.
The obtained qualitative and quantitative results of the study of this object using
holographic methods of measurement give the possibility to estimate measurements
during the loads and further to observe the behavior of the object under different
loads and limiting conditions, which simulate a real dental equipment.
In this study [109–119], based on the previous works, deformations of facial
part of the human skull under loads were determined using methods of holographic
interferometry and speckle-optics. The study of human skull bones isolated from the
skull itself constrains to a certain extent the character of deformation distribution
during loads, and that is why a task was set to simulate muscle load on the upper
jaw as well reciprocal effect of the upper and the lower jaws during their joining
considering the whole muscle complex of the human skull. A loading apparatus was
created, which includes the whole muscle complex of the human skull. The model of
the muscle load included all the main muscles, which influence during joining and
opening of the jaws and their interaction during jaw pressing.
The two-exposure and the real-time methods were used while investigating the
deformations of the facial surface of the skull with the holographic interferometry
method.
As the sensitivity of these measurements to the deformations, which are directed
parallel to the surface under study, is extremely small, in addition to the holographic
interferometry, we used the speckle-optical method of measurements, which makes
it possible to measure deformations along the bone surface. Holograms of the upper
and the lower jaws were simultaneously registered while measuring with the use of
the holographic interferometry methods. The speckle-interferograms were registered
in the same points.
As the qualitative analysis of the obtained holographic interferograms has shown
the deformation distribution depends greatly on the load. While pressing the jaw,
inhomogeneous distribution of the points of efforts takes place. We observe deformations of different directions with increasing the load because of the sliding contact
of the jaw teeth caused by the functional bite.
As it has been mentioned before while using our scheme of registration of holographic interferograms the vector of maximal sensitivity is directed normally to the
jaw surface and we can measure normal deformations as well.
During two-exposure speckle-interferogram registration with the same load, the
deformations of the object under study were measured which were directed along
the plane of the object.
The direction of the deformation vector and the value were measured according
to the period of the interference fringes.
During the registration of the speckle-interferogram, there was used a lens to
form a speckle-field in the focal area and the object image modulated by the specklestructure.
As a result of analysis of the experimental data, the distribution of the deformation
fields and the shift of the object under study were obtained. Thus, if the load of the
lower jaw is increasing, the gradual asymmetric deformation extension is observed
3 Holographic Interferometry for Studying …
deformations were observed in the alveolar area and the jaw joint in both planes. A
significant diminution of deformation was in the front area of the jaw.
The obtained qualitative and quantitative results of the study of this object using
holographic methods of measurement give the possibility to estimate measurements
during the loads and further to observe the behavior of the object under different
loads and limiting conditions, which simulate a real dental equipment.
In this study [109–119], based on the previous works, deformations of facial
part of the human skull under loads were determined using methods of holographic
interferometry and speckle-optics. The study of human skull bones isolated from the
skull itself constrains to a certain extent the character of deformation distribution
during loads, and that is why a task was set to simulate muscle load on the upper
jaw as well reciprocal effect of the upper and the lower jaws during their joining
considering the whole muscle complex of the human skull. A loading apparatus was
created, which includes the whole muscle complex of the human skull. The model of
the muscle load included all the main muscles, which influence during joining and
opening of the jaws and their interaction during jaw pressing.
The two-exposure and the real-time methods were used while investigating the
deformations of the facial surface of the skull with the holographic interferometry
method.
As the sensitivity of these measurements to the deformations, which are directed
parallel to the surface under study, is extremely small, in addition to the holographic
interferometry, we used the speckle-optical method of measurements, which makes
it possible to measure deformations along the bone surface. Holograms of the upper
and the lower jaws were simultaneously registered while measuring with the use of
the holographic interferometry methods. The speckle-interferograms were registered
in the same points.
As the qualitative analysis of the obtained holographic interferograms has shown
the deformation distribution depends greatly on the load. While pressing the jaw,
inhomogeneous distribution of the points of efforts takes place. We observe deformations of different directions with increasing the load because of the sliding contact
of the jaw teeth caused by the functional bite.
As it has been mentioned before while using our scheme of registration of holographic interferograms the vector of maximal sensitivity is directed normally to the
jaw surface and we can measure normal deformations as well.
During two-exposure speckle-interferogram registration with the same load, the
deformations of the object under study were measured which were directed along
the plane of the object.
The direction of the deformation vector and the value were measured according
to the period of the interference fringes.
During the registration of the speckle-interferogram, there was used a lens to
form a speckle-field in the focal area and the object image modulated by the specklestructure.
As a result of analysis of the experimental data, the distribution of the deformation
fields and the shift of the object under study were obtained. Thus, if the load of the
lower jaw is increasing, the gradual asymmetric deformation extension is observed