Analiza ivičnog pripoja kompozitnih smola za gleđ skening-elektronskom mikroskopijom nakon primene standardne i postepene tehnike fotopolimerizacije

Introduction Bonding between composite and hard dental tissue is most commonly assessed by measuring bonding strength or absence of marginal gap along the restoration interface. Marginal index (MI) is a significant indicator of the efficiency of the bond between material and dental tissue because it also shows the values of width and length of marginal gap. Objective The aim of this investigation was to estimate quantitative and qualitative features of the bond between composite resin and enamel and to determine the values of MI in enamel after application of two techniques of photopolymerization with two composite systems. Methods Forty Class V cavities on extracted teeth were prepared and restored for scanning electron microscope (SEM) analysis of composite bonding to enamel. Adhesion to enamel was achieved by Adper Single Bond 2 - ASB (3M ESPE), or by Adper Easy One - AEO (3M ESPE). Photopolymerization of Filtek Ultimate - FU (3M ESPE) was performed using constant halogen light (HIP) or soft start program (SOF). Results Quantitative and qualitative analysis, showed better mikromorphological bonding with SOF photopolymerization and ASB/FU composite system. Differences in MI between different photopolymerization techniques (HIP: 0.6707; SOF: 0.2395) were statistically significant (p lt 0.001), as well as differences between the composite systems (ASB/FU: 0.0470; AEO/ FU: 0.8651) (p lt 0.001) by two-way ANOVA test. Conclusion Better marginal adaptation of composite to enamel was obtained with SOF photopolymerization in both composite systems.Uvod Kvalitet veze kompozita za tvrda zubna tkiva se najčešće procenjuje jačinom vezivanja ili izostankom marginalne pukotine po obodu restauracija. Marginalni indeks (MI) je važan pokazatelj efikasnosti pripoja materijala za zubna tkiva jer istovremeno pokazuje vrednosti i širine i dužine marginalne pukotine. Cilj rada Cilj rada je bio da se kvantitativno i kvalitativno proceni veza kompozitnih materijala za gleđ i utvrde vrednosti MI u gleđi nakon primene dve tehnike svetlosne polimerizacije i dva kompozitna sistema. Metode rada Na ekstrahovanim zubima je restaurisano 40 kaviteta pete klase za analizu pripoja kompozita za gleđ skening- elektronskom mikroskopijom (SEM). Adhezija za gleđ je obezbeđivana primenom Adper Single Bond 2 - ASB (3M ESPE), odnosno primenom Adper Easy One - AEO (3M ESPE). Svetlosna polimerizacija kompozitnog materijala (Filtek Ultimate - FU; 3M ESPE) vršena je standardnim halogenim svetlom (HIP) ili tzv. soft start programom (SOF). Rezultati Kvantitativna i kvalitativna analiza je pokazala bolje mikromorfološko vezivanje kompozita za gleđ kod SOF osvetljavanja i ASB/FU kompozitnog sistema. Na osnovu dvosmernog ANOVA testa, razlike u vrednosti MI između različitih svetlosnopolimerizujućih tehnika (HIP: 0,6707 i SOF: 0,2395) bile su statistički značajne (p lt 0,001), kao i razlike između kompozitnih sistema (ASB/FU: 0,0470 i AEO/FU: 0,8651; p lt 0,001). Zaključak Bolji marginalni pripoj kompozita za gleđ obezbeđen je primenom SOF osvetljavanja kod oba kompozitna sistema

SEM analiza kvaliteta ivičnog pripoja kompozitnih ispuna za gleđ posle primene totalno nagrizajućeg i samonagrizajućeg adhezivnog sistema

Introduction Quality and durability of enamel/composite interface essentially depend on an adhesive restorative system. Objective The aim of this study was to evaluate the quality of marginal adaptation of composite adhesive systems to enamel by scanning electron microscopy (SEM), and to analyze the morphology of the enamel surface along margins of composite restorations, following exposure to cariogenic solution. Methods The study material included 56 extracted human third molars. Class V cavities were prepared with margins at enamel. Cavities were restored with Single Bond/Z250 and Single Bond/Filtek flow, using the total etch adhesive system, and Prompt-L-Pop/Z250 and Prompt-L-Pop/Filtek flow, using the self etch adhesive system. After the restorative procedure, the restorations were submitted to demineralization during 7 and 28 days. Samples were stored in a cariogenic solution (lactic acid, pH 4.5; 0.1 M) at 37°C or in deionized water (the control group). The margins of restorations and perimarginal enamel were examined by scanning electron microscope (SEM). The gap formations around restoration were measured on cervical, occlusal and approximate margins. Results The usage of the total etch adhesive system showed statistically significant lower marginal gap width around composite restoration, compared with the self etch system (p lt 0.01). The SEM examination also showed perimarginal enamel zones presenting several signs of demineralization and erosion (alteration of rods, porosities) after acting of a cariogenic solution, in both adhesive methods. Less alteration was found on the enamel surfaces not included in the perimarginal zone. Conclusion Treating the cavity with 35% phosphoric acid in the total etch system significantly improved the adaptation of the composite resins to enamel, compared with the self etch treatment. Stronger demineralization of the perimarginal enamel in a cariogenic solution was observed around all restorations in both adhesive systems.Uvod Kvalitet i trajnost veze gleđi i kompozitnih materijala zavisi, između ostalog, i od korišćenog adhezivnog restaurativnog sistema. Cilj rada Cilj istraživanja je bio da se analizom pomoću skening elektronske mikroskopije (SEM) proceni kvalitet ivičnog pripoja kompozitnih adhezivnih sistema i gleđi, odnosno prouče morfološke osobine gleđne površine duž ivica kompozitnih restauracija nakon delovanja kariogenog rastvora. Metode rada Kao materijal u istraživanju korišćeno je 56 ekstrahovanih humanih trećih molara. Na svim zubima su preparirani kaviteti pete klase s ivicama u gleđi. Kaviteti su restaurirani kompozitnim adhezivnim sistemima: Single Bond/Z250 i Single Bond/Filtek Flow, korišćenjem tehnike totalnog nagrizanja, i Prompt-L-Pop/Z250 i Prompt- L-Pop/Filtek Flow, primenom tehnike sa samonagrizajućim adhezivnim sistemima. Posle postupka restauracije zubi su izlagani demineralizaciji tokom sedam i 28 dana potapanjem u kariogeni rastvor (mlečna kiselina pH 4,5; 0,1 M) na 37°C ili držani u dejonizovanoj vodi (kontrolna grupa). Ivice restauracija i perimarginalna gleđ ispitivane su pomoću SEM. Ivična pukotina oko restauracija merena je u predelu vrata zuba, okluzivno i na aproksimalnim stranama. Rezultati Primena tehnike totalnog nagrizanja je pokazala značajno manju širinu ivične pukotine oko kompozitnih restauracija u odnosu na samonagrizajući sistem (p lt 0,01). SEM ispitivanja su takođe otkrila izrazitu demineralizaciju i eroziju ivične zone gleđi (oštećenja prizmi, poroziteti) nakon delovanja kariogenog rastvora kod oba adhezivna sistema. Na gleđnim površinama van perimarginalne zone uočena su neznatna oštećenja. Zaključak Tretman kaviteta sa 35-procentnom fosfornom kiselinom kod totalno nagrizajućeg postupka značajno poboljšava vezu kompozitnih smola za gleđ. Rastvaranje ivične gleđi u kariogenom rastvoru uočeno je oko svih restauracija i kod oba adhezivna sistema

The resistence of conditioned enamel to the effect of cariogenic solution

INTRODUCTION Enamel surface around restoration is very sensitive to the effect of cariogenic solution. It is the consequence of the manner the cavity is prepared before restoration, the existence of marginal cracks around restoration, that is, irregular polishing of filling. OBJECTIVE The aim of this study is to analyze the morphology of the marginal enamel surface around composite fifth class restoration after the application of cariogenic solution. METHOD In this study 28 extracted molars were used. After the V class preparation of the buccal crown surface, teeth samples were divided into two groups. The first group was restored with the composite system Single Bond +Z250, applying the total etching technique. The second group was restorated with Prompt L-pop +Z250 and by applying self-etching primers. After the cavity restoration, teeth samples were kept in demineralising solution (lactic acid, pH 4.5, 0.1 M) at the temperature of 37°C during 7 and 28 days. Control group samples were kept in distilled water during the experiment. The marginal enamel surface analysis was done by a scanning electron microscope. RESULTS The achieved results showed that there was a denivelation and severe demineralization of the perimarginal enamel zone after 7 and 28 days, while on the remaining enamel there were some minor changes. Along the marginal composite/ enamel joint there was the central type of demineralization of enamel prisms and preserved inter prismatic enamel. The existence of pores of different sizes and scattered enamel fractures was established. The marginal joint was mostly without any gaps in the first group samples, while in the second group samples there were narrow or wider edge gaps. CONCLUSION After the application of cariogenic solution, perimarrginal enamel showed conspicuous morphological damage in comparison to the remaining enamel surface