BOND STRENGTH COMPARISON OF THREE CORE BUILD-UP MATERIALS USED TO RESTORE MAXILLARY INCISOR TEETH

The aims of this study we-re to exa-mi-ne the ul-ti-ma-te strength of the re-sto-red ma-xil-lary in-ci-sors with com-po-si-te re-sin, den-tal amal-gam and glas-si-o-no-mer ce-ment as a tran-si-ti-o-nal re-sto-ra-tion. Fifty-six ex-trac-ted hu-man ma-xil-lary cen-tral in-ci-sors with in-tact and ca-ri-o-us den-tin we-re used. The con-trol gro-up con-si-sted of eight un-re-sto-red te-eth with in-tact den-tin. Ar-ti-fi-cial de-fect in den-tin was up to the half of the ana-to-mic crown of the to-oth. Af-ter co-re bu-ild-up pro-ce-du-re, each ro-ot of every spe-ci-men was mo-un-ted in auto-polyme-ri-zing acrylic re-sin blocks which we-re sto-red in dis-til-led wa-ter at 37°C one day be-fo-re te-sting. Then it was pla-ced in a spe-ci-ally adap-ted jig at an an-gle of 130 de-gre-es to la-bio-pa-la-tal axis and su-bjec-ted to a con-trol-led load that was re-cor-ded in a uni-ver-sal te-sting mac-hi-ne at a crosshead speed of 1 mm per mi-nu-te un-til fa-i-lu-re oc-cur-red. The-re we-re no sig-ni-fi-cant dif-fe-ren-ces among con-trol gro-up and re-sto-red te-eth with com-po-si-te re-sin and den-tal amal-gam with in-tact den-tin (p<0.05). In the gro-up with ca-ri-o-us-af-fec-ted den-tin, the-re we-re no dif-fe-ren-ces among re-sto-ra-ti-ve ma-te-ri-als and the va-lu-es we-re sta-ti-sti-cally sig-ni-fi-cantly lo-wer in com-pa-ri-son to the con-trol gro-up. Ba-sed on the da-te ob-ta-i-ned, we con-clu-ded that the hig-hest ove-rall strength of re-sto-red in-ci-sors with in-tact den-tin, when 50 per cent of the co-ro-nal part of the to-oth is mis-sing, was ac-hi-e-ved by using com-po-si-te re-sin and den-tal amal-gam as a tran-si-ti-o-nal re-sto-ra-tion and as a co-re bu-ild-up ma-te-rial. The ca-ri-es-af-fec-ted den-tin led to lo-wer bond strength of re-sto-red te-eth. Al-so it has been con-clu-ded that com-po-si-te re-sin has the best bond and ten-si-o-nal strength ra-tio.