[Procedure for the biological testing of substances in the guinea pig subcutaneous test. I. The results of an improved semiquantitative assessment of the histological criteria]. / Verfahren zur biologischen Prüfung von Werkstoffen mit dem Subkutantest an Meerschweinchen. I. Ergebnisse der verbesserten semiquantitativen Bewertung histologischer Merkmale.

Different materials were implanted into the subcutaneous connective tissue of guinea pigs to evaluate biotolerance by means of the tissue response. The investigations were carried out with reference materials and newly developed implant materials in short-term studies and in case control studies. The semiquantitative valuation standards lead mostly only to informing statements in the sense of a compatibility degree. Alternative assertions are possible when comparing very different materials.

[Procedure for the biological testing of substances in the guinea pig subcutaneous test. II. The results of mathematical evaluation and modelling of the morphometric data on the area of reaction]. / Verfahren zur biologischen Prüfung von Werkstoffen mit dem Subkutantest an Meerschweinchen. II. Ergebnisse der mathematischen Auswertung und Modellierung morphometrischer Daten aus der Reaktionszone.

The extent of the reaction area around implanted materials (connective tissue capsule) was measured by the electronic device system Densitron and was represented in its temporal dependence after implantation. A histocompatibility index (referring to titanium as reference material) was deduced from the course of the connective tissue adaptation (healing in process). Linear regression calculation shows that the healing in process can be described very well by means of a power function for the most of the investigated materials. A clear demarcation and classification of the tissue tolerance of the different materials was managed for the histocompatibility index and also by the obvious integral values of the experimentally found out and mathematically modelled subsidence curves of the connective tissue reaction (selected period: 90th to the 200th day after the implantation).

[Procedure for the biological testing of substances in the guinea pig subcutaneous test. III. The results of the quantitative determination of the cell division pattern in the area of reaction]. / Verfahren zur biologischen Prüfung von Werkstoffen mit dem Subkutantest an Meerschweinchen. III. Ergebnisse der quantitativen Bestimmung der Zellverteilungsmuster in der Reaktionszone.

The counting of the type of cells in the surroundings of implanted materials enables the estimation of specific material effects and improved the statement of the biologic testing methods. The explained method is described in the example of reference materials and is applied to different new materials for the estimation of their histocompatibility.