Suvremene spoznaje o kompozitnim materijalima

Composite materials are a tridimensional combination of at least two different materials mutually connected with a clearly recognizable coupling agent. In the development of composite materials, an outstanding place belongs to Michael G. Buonocore, who suggested etching the enamel surface with orthophosphoric acid; Rafael L. Bowen, who created composite resin, and to Nobuo Nakabayashi, who suggested hybridization of the dentin substrate and accomplished the promotion of adhesion by the infiltration of monomer into the tooth structure. Composite material consists of three fundamental parts: an organic resin matrix with a complimentary initiator of polymerization, an inorganic filler and a coupling agent. Composite materials were primarily developed for fillings on anterior and posterior teeth, but materials with similar composition are also used for an extremely large number of indications: pit and fissure sealants, adhesive cementation of ceramic and indirect composite restorations, for crown build-ups, temporary crowns and bridges, the bonding of brackets in orthodontics, making splints and root canal sealers. Contemporary composite materials are being constantly upgraded and have significantly improved physical and mechanical characteristics in comparison with previous generations, especially concerning the hardness, firmness, elasticity, resistance to bending, breaking, torsion and wear. However, since cross linking in net formation during polymerization leads to volumetric shrinkage and, consequently, polymerization stress that can affect the creation of a marginal gap and also compromise the longevity of the restoration, stress compensation represents the biggest scientific and clinical challenge. The future of composite materials is mirrored in several directions. The first one is finding low shrinking or expanding composite materials, the second one is the optimization of composite materials based on amorphous calcium phosphate which is a direct precursor of hydroxyapatite, the basic unit of tooth structure. Others include the incorporation of anti-bacterial agents into composites as well as the development of materials with self-adhesive properties.Kompozitni materijali su trodimenzijska kombinacija najmanje dva različita materijala koji su međusobno povezani jasno prepoznatljivom silanskom vezom. U razvoju kompozitnih materijala, iznimno mjesto pripada Michael G. Buonocoreu, koji je predložio jetkanje caklinske površine ortofosfornom kiselinom, Rafael L. Bowenu, koji je stvorio kompozitnu smolu i Nobuo Nakabayashiu, koji je predložio hibridizaciju dentinskog supstrata i tako ostvario promociju adhezije pomoću infiltracije monomera u zubnu strukturu. Kompozitni materijali sastoje se od tri temeljna dijela: organske smolaste matrice i odgovarajućeg inicijatora polimerizacije, anorganskog punila te svezujućeg sredstva. Kompozitni materijali razvili su se primarno za ispune prednjih i stražnjih zubi, ali se materijali sličnog sastava danas koriste za iznimno puno indikacija: pečaćenje fisura i jamica, adhezijsko cementiranje keramičkih i indirektnih kompozitnih restoracija, za izradu nadogradnji, izradu privremenih krunica i mostova, vezanje bravica u ortodonciji, izradu splintova te za ispun korijenskog kanala. Suvremeni kompozitni materijali se stalno nadograđuju i imaju znatno usavršena fizičko-mehanička svojstva u odnosu na prethodne generacije, poglavito tvrdoću, čvrstoću, elastičnost, otpornost na savijanje, kidanje, torziju i trošenje. Međutim, kako križno povezivanje u mrežu tijekom polimerizacije dovodi do volumetrijskog skupljanja, a posljedično i polimerizacijskog stresa koji može u značajnoj mjeri utjecati na stvaranje rubne pukotine i kompromitaciju trajnosti restorativnog zahvata, kompenzacija stresa predstavlja najveći znanstveni i klinički izazov. Budućnost kompozitnih materijala ogleda se u nekoliko smjerova. Prvi je iznalaženje niskoskupljajućih ili ekspandirajućih kompozitnih materijala, a drugi optimizacija kompozitnih materijala temeljenih na amorfnom kalcijevom fosfatu, koji je direktni prekursor hidroksilapatita, osnovne gradbene jedinice zuba. Ostali pristupi uključuju inkorporaciju antibakterijskih agensa u kompozite te razvoj materijala sa samovezujućim svojstvima

Mikrotvrdoća bulk-fill kompozitnih smola

The aim of the study was to determine microhardness of high- and low-viscosity bulk-fill composite resins and compare it with conventional composite materials. Four materials of high-viscosity were tested, including three bulk-fills: QuiXfi l (QF), x-tra fil (XTF) and Tetric EvoCeram Bulk Fill (TEBCF), while nanohybrid composite GrandioSO (GSO) served as control. The other four were low-viscosity composites, three bulk-fill materials: Smart Dentin Replacement (SDR), Venus Bulk Fill (VBF) and x-tra base (XB), and conventional control material X-Flow (XF). Composite samples (n=5) were polymerized for 20 s with Bluephase G2 curing unit. Vickers hardness was used to determine microhardness of each material at the surface, and at 2-mm and 4-mm depth. GSO on average recorded significantly higher microhardness values than bulk-fill materials (p<0.001). The low-viscosity composite XF revealed similar microhardness values as SDR, but signifi cantly lower than XB (p<0.001) and significantly higher than VBF (p<0.001). Microhardness of high-viscosity bulk-fill materials was lower than microhardness of the conventional composite material (GSO). Surface microhardness of low-viscosity materials was generally even lower. The microhardness of all tested materials at 4 mm was not different from their surface values. However, additional capping layer was a necessity for low-viscosity bulk-fill materials due to their low microhardness.Svrha istraživanja bila je odrediti mikrotvrdoću visoko-viskoznih i nisko-viskoznih bulk-fill kompozitnih smola i usporediti ih s konvencionalnim kompozitnim materijalima. Četiri visoko-viskozna materijala su testirana, od toga tri bulk-fill: QuiXfi l (QF), x-tra fil (XTF) i Tetric EvoCeram Bulk Fill (TEBCF); nanohibridni kompozit GrandioSO (GSO) služio je kao kontrola. Ostala četiri materijala bila su nisko-viskozna, tri bulk-fill: Smart Dentin Replacement (SDR), Venus Bulk Fill (VBF) i x-tra base (XB) te konvencionalni kontrolni materijal X-Flow (XF). Kompozitni uzorci (n=5) polimerizirani su 20 s polimerizacijskom lampom Bluephase G2. Mikrotvrdoća svakog materijala na površini te na dubini od 2 i 4 mm je određena po Vickersu. GSO je u prosjeku imao značajno više vrijednosti mikrotvrdoće od ostalih materijala (p<0,001). Niskoviskozni kontrolni kompozit XF imao je slične vrijednosti kao SDR, ali značajno niže nego nego XB (p<0,001) i značajno više nego VBF (p<0,001). Mikrotvrdoća visoko-viskoznih bulk-fill materijala je niža nego kod konvencionalnog kompozitnog materijala GSO. Površinska mikrotvrdoća nisko-viskoznih materijala je općenito još niža. Mikrotvrdoća svih testiranih materijala na dubini od 4 mm se ne razlikuje od njihovih površinskih vrijednosti mikrotvrdoće. Dodatni sloj kompozita za prekrivanje nisko-viskoznih bulk-fill materijala je nužan zbog njihove male mikrotvrdoće

Učinak dentinskih adheziva na učestalost mikronukleusa u limfocitima periferne krvi in vitro

Dental adhesives come into direct contact with oral tissues. Due to this close and long-term contact, the materials should exhibit a high degree of biocompatibility. The aim of this study was to evaluate the genotoxic effect of dental adhesives on human lymphocytes in vitro. Polymerized dental adhesives (Excite, Adper Single Bond 2, Prompt L-pop and OptiBond Solo Plus) were eluted in dimethyl sulfoxide for 1 hour, 24 h and 120 h (5 days). Thereafter, lymphocyte cultures were treated with different concentrations of eluates (0.2 μg/mL, 0.5 μg/mL and 5 μg/mL) obtained from each of the tested materials. Genotoxicity was evaluated by micronucleus test. The χ2-test was used on statistical analysis (p<0.05). After elution period of 1 h, only the highest dose of all tested materials affected the measured cytogenetic parameters. After 24 h, genotoxicity was demonstrated only in cultures treated with eluates in concentrations of 0.5 μg/mL and 5 μg/mL. Based on the results, it is concluded that the use of dental adhesives causes genotoxic effects in human lymphocytes. Toxic effect of these dental adhesives increases with the tested material concentration and decreases with the length of elution period.Stomatološki dentinski adhezivi dolaze u izravan dodir s oralnim tkivima. Zbog ovog bliskog i dugotrajnog kontakta ove materijale treba obilježavati visok stupanj biokompatibilnosti. Svrha ovoga rada bila je procjena genotoksičnog učinka dentinskih adheziva na ljudskim limfocima in vitro. Polimerizirani adhezivi (Excite, Adper Sngle Bond 2, Prompt L-pop i OptiBond Solo Plus) eluirani su u dimetil sulfoksidu kroz 1 h, 24 h i 120 h (5 dana). Nakon toga su kulture limfocita tretirane različitim koncentracijama eluata (0,2 μg/mL, 0,5 μg/mL i 5 μg/mL) dobivenim iz ispitivanih materijala. Za procjenu genotoksičnosti koristio se mikronukleus test, dok se χ2-test koristio za statističku analizu (p<0,05). Adhezivi pokazuju genotoksičan učinak u kulturi limfocita nakon jednosatnog tretiranja eluatom koncentracije 5 μg/mL. Nakon 24 h svi su ispitivani adhezivi pokazali genotoksičnost u koncentraciji 0,5 μg/mL i 5 μg/mL. Na temelju rezultata može se zaključiti kako upotreba adheziva izaziva genotoksični učinak u ljudskim limfocitima. Toksični učinak povećava se s koncentracijom ispitivanog materijala, a smanjuje s vremenom trajanja eluacije

Utjecaj brze polimerizacije na apsorpciju vode i topljivost bulk-fill kompozita

Objectives: The aim of the study was to examine the impact of rapid high-intensity polymerization on water sorption and solubility of a new generation of bulk-fill composite materials. Materials and methods: Five materials were tested: a conventional composite Filtek Z250 (3M, St. Paul, USA) and four bulk-fill composites, Filtek One Bulk Fill (3M), Tetric PowerFill (Ivoclar Vivadent, Schaan, Liechtenstein), Tetric PowerFlow (Ivoclar Vivadent), SDR Plus (Dentsply, Konstanz, Germany). Composite specimens with a 9-mm diameter and a 2-mm height (n = 6) were polymerized with a high-intensity curing unit (Bluephase® PowerCure, Ivoclar Vivadent). The control group was polymerized for a total of 40 s on both sides (1193 mW / cm 2 ) and 3s group for 3 s on one side (3053 mW/cm2 ). Water sorption and solubility were measured by ISO 4049 method up to 30 days of immersion. The results were statistically analyzed using one-way ANOVA with Tukey post-hoc correction. Different polymerization protocols for the same material were compared by t-test (p < 0.05). Results: The 3s polymerization protocol increased the solubility of all materials. Filtek One Bulk Fill showed the highest water sorption and solubility values, and Tetric PowerFlow proved to be a stable material with low values of tested parameters. During immersion, a saturation of specimens was achieved in low-viscosity bulk-fill composites within two weeks, while in other materials it was not achieved within 30 days, or more, following the immersion. Conclusions: Rapid polymerization caused an increase in solubility, which could affect the biocompatibility of the investigated materials not intended for the 3s curing. SDR Plus and Filtek One Bulk Fill should not be polymerized with rapid high-intensity curing due to increased solubility that exceeds ISO 4049:2009 limits.Svrha: Svrha ovoga istraživanja bila je ispitati utjecaj brze polimerizacije visokoga intenziteta na ap-sorpciju vode i topljivost nove generacije bulk-fill kompozitnih materijala. Materijal i postupci: Is-pitano je pet materijala: konvencionalni kompozit Filtek Z250 (3M, St. Paul, SAD) i četiri bulk-fill kompozita – Filtek One Bulk Fill (3M), Tetric PowerFill (Ivoclar Vivadent, Schaan, Lihtenštajn), Tetric PowerFlow (Ivoclar Vivadent) i SDR Plus (Dentsply, Konstanz, Njemačka). Kompozitni uzorci promjera 9 mm i visine 2 mm (n = 6) polimerizirani su svjetlom visokoga intenziteta (Bluephase® PowerCure, Ivoclar Vivadent). Kontrolna skupina uzoraka polimerizirana je obostrano tijekom ukupno 40 sekun-da (1193 mW/cm2 ), a trosekundna jednostrano 3 sekunde (3053 mW/cm2 ). Apsorpcija vode i toplji-vost mjereni su metodom ISO 4049 do 30. dana imerzije. Rezultati su statistički obrađeni s pomoću jednosmjerne ANOVA-e uz Tukeyevu post-hoc korekciju. Različiti protokoli polimerizacije za isti ma-terijal uspoređeni su t-testom (p < 0,05). Rezultati: Trosekundni protokol polimerizacije povisio je to-pljivost svih materijala. Filtek One Bulk Fill pokazao je značajno najviše vrijednosti u apsorpciji vode i topljivosti, a Tetric PowerFlow pokazao se stabilnim materijalom s niskim vrijednostima ispitanih pa-rametara. Tijekom imerzije je saturacija uzoraka niskoviskoznih bulk-fill kompozita postignuta nakon dva tjedna, a kod ostalih materijala nije postignuta unutar 30 ili više dana imerzije uzoraka. Zaklju-čak: Brza polimerizacija prouzročila je povećanje topljivosti što bi moglo utjecati na biokompatibil-nost ispitanih materijala koji nisu namijenjeni trosekundnoj polimerizaciji. SDR Plus i Filtek One Bulk Fill ne bi se smjeli polimerizirati brzom polimerizacijom visokoga intenziteta zbog povećane topljivosti koja premašuje ograničenja standarda ISO 4049:2009

Mjerna točnost stomatoloških radiometara ovisno o vremenu mjerenja

Inadequate intensity of the polymerization light source can compromise the quality and longevity of dental composite restorations. In order to maintain optimal strength of polymerization devices, regular control of polymerization units is necessary. The aim of this study was to compare the accuracy of two radiometers in the measurement of light intensity of photopolymerization devices concerning the time point of measurement. Light intensity measurements of 16 halogen and 8 LED curing lights were performed using three different devices at the beginning as well as 10 and 40 seconds after the start of illumination. Two were handheld radiometers: Bluephase meter (BM) and Cure Rite (CR), while an integrating sphere (IS) represented the reference device. Data were statistically analyzed using Friedman’s test and Wilcoxon signed-rank test (p<0.05). The values at the beginning and after 10 seconds measured by BM were significantly higher than the measurements by IS, whereas CR showed higher values after 10 and 40 seconds. Both commercial radiometers tended to overestimate the light intensity of LED and halogen curing units when compared to the reference device. The time point of measurement influences the output value. The heating of radiometers was proposed as a possible explanation for the inaccuracy.Neodgovarajući intenzitet svjetlosti polimerizacijskih uređaja može ugroziti kvalitetu i dugotrajnost stomatoloških kompozitnih restoracija. Kako bi se očuvala optimalna snaga polimerizacijskih uređaja neophodna je redovita kontrola. Svrha ovoga ispitivanja bila je usporediti dva radiometra u točnosti mjerenja intenziteta svjetlosti fotopolimerizacijskih uređaja uzimajući u obzir vrijeme mjerenja. Mjerenja intenziteta svjetlosti 16 halogenih i 8 LED polimerizacijskih lampa provedena su pomoću tri uređaja na početku iluminacije, te nakon 10 i 40 sekunda. Korištena su dva ručna radiometra: Bluephase meter (BM) i Cure Rite (CR), dok je integrirajuća sfera (IS) predstavljala referentni uređaj. Podaci su statistički analizirani pomoću Friedmanova testa i Wilcoxonova signed-rank testa (p<0.05). Vrijednosti izmjerene pomoću BM na početku i nakon 10 sekunda bile su značajno više od onih izmjerenih pomoću IS, dok je CR pokazao više vrijednosti nakon 10 i 40 sekunda. Oba komercijalno dostupna radiometra pokazala su tendenciju prikazivanja viših vrijednosti intenziteta svjetlosti LED i halogenih polimerizacijskih uređaja u usporedbi s referentnim uređajem. Vrijeme mjerenja ima utjecaja na očitanje intenziteta svjetlosti. Zagrijavanje radiometara je predloženo kao moguće objašnjenje njihove nepreciznosti

Remineralizing amorphous calcium phosphate based composite resins: the influence of inert fillers on monomer conversion, polymerization shrinkage, and microhardness

AIM: To determine if the addition of inert fillers to a bioactive dental restorative composite material affects its degree of conversion (DC), polymerization shrinkage (PS), and microhardness (HV). METHODS: Three amorphous calcium phosphate (ACP)-based composite resins: without added fillers (0-ACP), with 10% of barium-glass fillers (Ba-ACP), and with 10% of silica fillers (Si-ACP), as well as commercial control (Ceram•X, Dentsply DeTrey) were tested in laboratory conditions. The amount of ACP (40%) and the composition of the resin mixture (based on ethoxylated bisphenol A dimethacrylate) was the same for all ACP materials. Fourier transform infrared spectroscopy was used to determine the DC (n = 40), 20 min and 72 h after polymerization. Linear PS and Vickers microhardness (n = 40) were also evaluated. The results were analyzed by paired samples t test, ANOVA, and one-way repeated measures ANOVA with Student-Newman-Keuls or Tukey’s post-hoc test (P = 0.05). RESULTS: The addition of barium fillers significantly increased the DC (20 min) (75.84 ± 0.62%) in comparison to 0-ACP (73.92 ± 3.08%), but the addition of silica fillers lowered the DC (71.00 ± 0.57%). Ceram•X had the lowest DC (54.93 ± 1.00%) and linear PS (1.01 ± 0.24%) but the highest HV (20.73 ± 2.09). PS was significantly reduced (P < 0.010) in both Ba-ACP (1.13 ± 0.25%) and Si-ACP (1.17 ± 0.19%) compared to 0-ACP (1.43 ± 0.21%). HV was significantly higher in Si-ACP (12.82 ± 1.30) than in 0-ACP (10.54 ± 0.86) and Ba-ACP (10.75 ± 0.62) (P < 0.010). CONCLUSION: Incorporation of inert fillers to bioactive remineralizing composites enhanced their physical-mechanical performance in laboratory conditions. Both added fillers reduced the PS while maintaining high levels of the DC. Silica fillers additionally moderately improved the HV of ACP composites

Antimicrobial Effectiveness of Intracanal Ozone Treatment

Svrha: Ovim se radom željela procijeniti količina aerobnih, anaerobnih i ukupnog broja bakterijskih kolonija nakon kemijsko-mehaničke obrade korijenskog kanala te dodatne obrade i dezinfekcije ozonom. Materijali i metode: U ovom istraživanju sudjelovala su dvadeset i tri pacijenta s periapikalnom lezijom (<5 mm) zabilježenom na retroalveolarnoj rendgenskoj slici i korišten je isti broj jednokorijenskih zuba (n=23). Za mikrobiološku analizu uzeta su tri brisa – neposredno prije (B1) mehaničke instrumentacije i irigacije 2,5-postotnom otopinom natrijeva hipoklorita i poslije toga postupka (B2) te nakon kemijsko-mehaničke obrade i dodatnog tretmana korijenskog kanala ozonom (B3). Brisevi su uzeti sterilnim papirnatim štapićima, bakterije su kultivirane, a rezultati su interpretirani nakon 14 dana koristeći se sustavom API 20A. Podaci su analizirani testom Wilcoxon Signed Rank. Rezultati: Razlike između skupina B1 i B2, B1 i B3, B2 i B3 za sve tri skupine bakterija: aerobne i anaerobne bakterije te ukupan broj bakterija bili su statistički značajni (p<0,05). Zaključak: Obje metode imale su dobar učinak i smanjile su broj bakterija prisutnih u korijenskom kanalu. Dodatnim tretmanom ozonom, nakon kemijsko-mehaničke obrade, još se smanjio broj aerobnih i anaerobnim bakterija, u usporedbi s mjerenjima neposredno prije kemijsko-mehaničke obrade i nakon nje. Kako bi se smanjio i reducirao broj bakterija, u svakodnevnoj se uporabi u kliničkoj praksi preporučuje dodatna primjena ozona kao dezinfekcijskog sredstva u korijenskom kanalu.Aim: The aim of this study was to determine the amount of aerobic, anaerobic, and total number of bacterial colonies after chemomechanical root canal treatment and after additional intracanal disinfection using ozone. Materials and Methods: Twenty - three patients with the same number of single rooted teeth (n=23) with periapical lesion (<5 mm) observed on retroalveolar radiogram or panoramic radiograph took part in this study. For the microbiological analysis three swabs were taken: immediately before (B1), after mechanical instrumentation and irrigation with 2.5% sodium hypochlorite (B2) and after chemomechanical treatment and additional intracanal ozone application (B3). Swabs were taken with sterile paper points, bacteria were cultivated and the results were interpreted after 14 days using the API 20A system. The data were analyzed by Wilcoxon Signed Rank Test measuring the number of bacterial colonies before and after the root canal treatment. Results: The difference between groups B1 and B2, B1 and B3 and B2 and B3 for all three groups: aerobic bacteria, anaerobic bacteria and total number of bacteria was statistically significant (p<0.05). Conclusion: Both methods showed a strong effect in bacterial number reduction.After the chemomechanical and additional ozone root canal treatment, the number of aerobic and anaerobic bacterial colonies further decreased compared to the measurements immediately before and after the chemomechanical root canal treatment. Because of the improvements in bacterial reduction after additional application of ozone in the root canal, this procedure is recommended for use in clinical practice

Influence of Different Types of Fillers on the Degree of Conversion of ACP Composite Resins

Kompozitnim materijalima koji sadržavaju amorfni kalcijev fosfat (ACP) kao aktivni remineralizirajući sastojak dodana su inertna punila kako bi se smanjilo njihovo polimerizacijsko skupljanje i poboljšala mehanička svojstva. Svrha: Svrha istraživanja bila je ispitati utjecaj dodavanja različitih vrsta silaniziranih anorganskih punila na stupanj polimerizacije (SP) kompozita temeljenih na ACP-u. Materijal i postupci: Testirano je sedam ACP-kompozita: ACP-kontrola (40 % ACP, 60 % smola) i šest koji su sadržavali 40 posto ACP-a, 5 posto ili 10 posto neaktivnih punila i 55 posto ili 50 posto smole. U kompozitne materijale uključena su silika-punila (12nm; 4 – 6% silanizacija) te barijeva (0,77μm; 6% silanizacija) ili stroncijeva staklena punila (0,99μm; 3,2% silanizacija). Nanohibridni kompozit CeramX (Dentsply DeTrey, Njemačka) također je služio kao kontrolni materijal. Kompozitni uzorci (10/ispitnoj skupini) polimerizirani su 40 sekundi uređajem Bluephase C8 (Ivoclar Vivadent, Liechtenstein). Stupanj polimerizaciuje određen je Fourier transform infracrvenom spektroskopijom (System 2000 FTIR spectrometer; Perkin Elmer, Velika Britanija) 20 minuta i 72 sata nakon polimerizacije. Rezultati: Dodavanje 10 posto silika-punila (74,14% i 75,90%) i 5 posto stroncijevih staklenih punila (76,23% i 76,29%) nije štetno utjecalo na stupanj polimerizacije ACP-kompozitnih smola. Kod obaju kompozitnih materijala s dodanim barijevim punilima smanjio se SP u odnosu na ACP-kontrolu. Kako se i očekivalo, ACP-kontrola s najmanjim volumenom punila zadržala je najviši SP (75,38% i 76,05%), a CeramX je imao statistički najniži (56,87% i 57,97%). Zaključak: Iako je primjesa određenih punila pridonijela smanjenju stupnja polimerizacije ACP-kompozitnih smola, uzimajući u obzir da je ipak uvelike nadmašen stupanj polimerizacije komercijalno dostupnog kontrolnog materijala, može se zaključiti da neće izazvati neželjene učinke povezane s niskim SP-om.In order to diminish the polymerization shrinkage and improve mechanical properties of the composite materials containing amorphous calcium phosphate (ACP) as an active remineralizing ingredient, inert fillers were introduced into formulation. Purpose: The aim of the study was to examine the influence of the addition of different types of silanized inorganic fillers on the degree of conversion (DC) of the ACP based composites. Material and Methods: Seven ACP composites were tested: ACP control (40% ACP, 60% resin) and six composites containing 40% ACP, 5% or 10% non-releasing fillers and 55% or 50% resin. Silica fillers (12nm; 4-6% silanization), barium (0.77μm; 6% silanization) or strontium glass fillers (0.99μm; 3.2% silanization) were included into the pastes. Nanohybrid composite CeramX (Dentsply DeTrey, Germany) also served as a control. Composite specimens (10/experimental group) were polymerized for 40 sec by Bluephase C8 curing unit (Ivoclar Vivadent, Liechtenstein). The DC was determined by Fourier- transform infrared spectroscopy (System 2000 FTIR spectrometer; Perkin Elmer, UK) 20 min and 72 h after polymerization. Results: The addition of 10% of silica (74.14% and 75.90%) and 5% of strontium glass fillers (76.23% and 76.29%) did not have a detrimental influence on the DC of ACP composite resins. Both composites with added barium fillers showed the reduction in DC when compared to the ACP control. As expected, the ACP control with the lowest filler volume retained the highest conversion rate (75.38% and 76.05%), and CeramX had significantly lowest DC (56.87% and 57.97%). Conclusions: Even though the admixture of certain fillers yielded decrease of the DC of ACP composite resins, and considering the fact that it still greatly exceeded the DC of the commercial control, it might be concluded that they will not cause adverse effects associated with low DC