[The construction principle of bone. II. Microstructure].

On the basis of the ultrastructure of the Haversian lamellar system of bones analyses from the biomechanical viewpoint were undertaken. Instead of computed results preference was given to comparisons with tubes, fibres and nets so as to demonstrate clearly the building principle and movement phenomena. From the course of the collagenous fibres the tensile strains could be discerned which facilitated to determine also the direction of the compressive strains.

[Fundamentals of the biomechanics of hard tissues].

On the basis of an analysis of such methods that have led to the establishment of the Newtonian laws some problems of the interdisciplinary agreement between mechanics and biology, especially those concerning hard tissues, were discussed. In the light of examples it is shown that comparisons with technical constructions to explain form and function of bones are not sufficient since similarity of form is no proof of identical function. Mechanical phenomena of living matter can be investigated merely by their own movements whereby the differing qualities and reactions of the material have to be taken into priority consideration.

[The structural basis of bone I].

Divergent opinions on the relations between mechanical forces and bones motivated the authors to reevaluate the problem in its entirely. First, the most important environmental forces were recorded in order to be able to assess the primary relationships to living matters. The fundamental differences between the distribution of mechanical strain in a cell and in an inanimate solid substance were analysed.

The gnathic system in obese and diabetics. I (Basic relationship of function and form).

The authors pay complex attention to the research of the gnathic system, focused first of all to the mechanical interactions towards solid formations of the gnathic system. The results of their analysis show, that in the first cell already differentation to tensile functions of the membrane and compressive functions of its contents (cytoplasm) exists. In the osseous tissue the mechanical strain is also distributed to different substances, reacting differently to the mechanical stress according to their aggregate state--the liquid state secures an equal distribution of the developing compression, the collagens intercept and cushion the arising traction, and the mineral component the oriented compressions.

The gnathic system in obese and diabetics. II. (Changes in the hard tissues).

The authors pay increased attention to issues concerning correct interpretation of mechanical phenomena of the hard tissues that facilitate interdisciplinary cooperation with technical specialists. Equal attention is paid also to terms of compressive stress and compressive strain. Analyzing the crown of the teeth the authors found striking coincidence between the developing dental caries localization and lower values of compressive strains.