Healing caps are used during the healing period after abutment connection on titanium implants of the Branemark type. These healing caps consist of a screw embedded in polyamide-6 (PA-6) which is considerably weakened during this healing period. The properties of PA-6 and poly(4-methyl-1-pentene) (PMP) were studied. Storage in water at 37 degrees C led to a marked reduction in the flexural modulus of PA-6, but only a minor decrease for PMP. PA-6 showed a marked increase in volume due to water uptake, whereas PMP showed no significant change in volume. The improved properties of PMP compared to PA-6 when used for healing caps were demonstrated. The results of an agar overlay cytotoxicity test indicated that both PMP and PA-6 were nontoxic under laboratory controlled conditions.


Polymers for healing caps on titanium implants
Ekstrand K, Ruyter IE.
Biomaterials. 1987 Jan; 8(1): 38-41