Influence of different bonding agents on marginal sealing quality of amalgam restorations

Abstract

Introduction. Although advanced adhesive systems are in use, marginal microleakage is one of the greatest problems of contemporary restorative dentistry. Objective. The aim of this in vitro study was to evaluate the influence of different bonding agents on the marginal sealing quality of class II amalgam restorations. Methods. Forty freshly extracted human premolar and molar teeth were divided into four groups with 10 teeth in each one. Class II preparations were prepared and different adhesives were applied as follows: group I - Amalgam Liner? (Voco); group II - ONE-STEP? PLUS (Bisco); group III - PQ 1 (Ultradent). Group IV was used as a control, without any bonding agent. Amalgam (Cavex Non Gamma 2, Cavex) was hand-condensed into each preparation. Specimens were thermocycled 200 times at the following temperatures: 5-7?C, 37?C and 57-59?C, and were then immersed into 1% solution of gentian violet for 72 hours. The teeth were sectioned longitudinally and microleakage was graded in the area of the gingival and occlusal quantity rim using a binocular magnifying glass with 25 times magnification. Results. The highest microleakage was recorded in the Amalgam Liner group; 1526.0 ?m at the gingival wall and 694.5 ?m at the occlusal cavity wall. The lowest dye penetration was observed in the PQ1 group; 589.5 ?m at the gingival wall, and 599.9 ?m at the occlusal wall of the restoration. ANOVA test showed that there was a statistically significant difference of dye penetration values at the gingival wall among all examination groups (p<0.01). No statistically significant differences were found comparing microleakage values at the occlusal wall. Conclusion. Results of this study showed that the best marginal sealing was accomplished by using the PQ1 bonding agent.Uvod. I pored primene najsavremenijih adhezivnih materijala, marginalno mikrocurenje je jedan od najvecih problema savremene restaurativne stomatologije. Cilj rada. Cilj ovog istrazivanja in vitro bio je da se ispita uticaj razlicitih adhezivnih sredstava na kvalitet rubnog zaptivanja amalgamskih restauracija II klase. Metode rada. Cetrdeset sveze ekstrahovanih intaktnih humanih premolara i molara podeljeno je u cetiri grupe od po 10 zuba. Nakon preparacije kaviteta II klase primenjena su adhezivna sredstva prema uputstvu proizvodjaca: prva grupa - Amalgam Liner? (Voco), druga grupa - ONE-STEP? PLUS (Bisco), treca grupa - PQ1 (Ultradent); u cetvrtoj (kontrolnoj) grupi nije upotrebljeno adhezivno sredstvo. Amalgam (Cavex Non Gamma 2, Cavex) je rucno kondenzovan u kavitetu. Uzorci su termociklirani 200 puta na temperaturama od 5-7?C, 37?C i 57-59?C, a zatim potopljeni u jednoprocentni rastvor gencijane violet tokom naredna 72 sata. Uzorci su potom isecani longitudinalno, a mikrocurenje je mereno u predelu gingivalne i okluzalne ivice kaviteta pomocu binokularne lupe sa mikrometarskim razmernikom i uvelicanjem od 25 puta. Rezultati. Najvece mikrocurenje je ustanovljeno kod uzoraka zuba prve grupe: 1526,0 ?m na gingivalnom zidu i 694,5 ?m na okluzalnom zidu. Najmanji prodor boje uocen je kod uzoraka trece grupe: 589,5 ?m u predelu gingivalnog i 599,9 ?m u predelu okluzalnog zida. Primenom ANOVA testa izmedju svih ispitivanih grupa ustanovljena je statisticki znacajna razlika u prodoru boje na gingivalnom zidu (p<0,01). Razlike u mikrocurenju nisu bile statisticki znacajne u predelu okluzalnog zida. Zakljucak. Rezultati istrazivanja pokazuju da je najbolje marginalno zaptivanje ostvareno primenom adhezivnog sredstva PQ1.