Adresa za dopisivanje Ivan Galic Dom zdravlja Splitsko-dalmatinske županije Stomatoloska ordinacija – Kamenmost Kamenmost bb, 21262 Kamenmost Tel: +385 21 848 052 Fax: +385 21 848 052 igalic2@sfzg.hr Sažetak Određivanje dentalne dobi kod djece u razvoju važno je u pedodonciji, ortodonciji i forenzicnoj znanosti. Najcesce se primjenjuje postupak prema Demirjianu nastao na francusko-kanadskom uzorku djece 1973. godine na temelju Tanner-Whitehousova postupka (TW-a) procjene skeletne zrelosti. Svrha: Željela se ispitati tocnost Demirjianova postupka za određivanje dentalne dobi kod djece u Bosni i Hercegovini (BiH). Ispitanici i postupci: Prilagođene Demirjianove tablice razvojnih stadija sedam zuba s lijeve strane mandibule iz 1976. godine ispitane su na ukupno 1106 panoramskih snimki bosansko-hercegovacke djece (597 djevojcica i 509 djecaka dobi od 5 do 14 godina). Nakon toga je T-testom za zavisne uzorke dentalna dob bila uspoređena s kronoloskom. Rezultati: Razlika između dentalne i kronoloske dobi bila je u rasponu od 0,60 do 2,17 godina kod djevojcica i 0,63 do 2,60 kod djecaka. Rezultati upozoravaju na precijenjenost dentalne dobi u usporedbi s Demirjianovim standardima iz 1976. Zakljucak: Demirjianovi standardi za francusko-kanadsku djecu prema kojima se određuje dentalna dob nisu adekvatni za primjenu kod djece u Bosni i Hercegovini. Nužno je i dalje istraživati na vecem uzorku i odrediti specificne standarde za određivanje dentalne dobi kod bosansko-hercegovacke djece. Kljucne rijeci dob; određivanje pomocu zuba; Forenzicka stomatologija; radiologija, panoramska; Bosna i Hercegovina 1 Student doktorskog studija, Zavod za dentalnu antropologiju Stomatoloskog fakulteta Sveucilista u Zagrebu, Hrvatska PhD student, Department of Dental Anthropology School of Dental Medicine University of Zagreb, Croatia 2 Stomatoloski fakultet Sveucilista u Sarajevu, Bosna i Hercegovina School of Dental Medicine University of Sarajevo, Bosnia and Herzegovina Zdravstveni fakultet Sveucilista u Zenici, Bosna i Hercegovina Faculty of health, University of Zenica, Bosnia and Herzegovina 4 Medicinski fakultet Sveucilista u Banjaluci, Bosna i Hercegovina School of Medicine, University of Banja Luka, Bosnia and Herzegovina 5 Student doktorskog studija, Medicinski fakultet Sveucilista u Zagrebu, Hrvatska PhD student, School of Medicine, University of Zagreb, Croatia

Composition and laboratory procedures have the greatest influence on the microstructure, mechanical, and electrochemical properties of dental casts. Objectives: The aim of this study was to evaluate the metallographic properties of high gold-based dental castings, Dentor S, and low gold-based dental castings, Midor S, used for the same fixed prostehtic indication. Material and methods: Samples were centrifugally cast in a phosphate-bonded investment and cooled at room temperature. The microstructure was analyzed and photographed with light microscope and scanning electron microscope. The grain size and the percentage porosity were evaluated. The Vickers microhardness was tested. T-test for independent samples (a=0.05) was used for statistical analysis. Results: Micrographs showed difference in microstructure, homogeneity and grain size. Average grain size number according to ASTM112/96 of Dentor S (7.72± 0.23) was significantly greater comparing with Midor S (6.26± 0.19) castings. Percentage porosity of castings was calculated from average impurities and defects, where Dentor S (0.62%± 0, 24%) was significantly more porous than Midor S (0.49%± 0.19%). Vickers microhardness of Midor S castings (HV0.1=169.98± 10.61) was significantly greater then those of Dentor S castings (HV0.1=157.58± 15.42). Conclusion: It can be concluded that composition, under the same laboratory procedures, has a critical influence on microstructure and microhardness of conventional gold-based castings. To ensure functional and technical durability of restoration, selection of the alloy should be based on its composition and mechanical properties as on the patient’ s bite forces.