28 research outputs found
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 razliÄita materijala koji su meÄusobno povezani jasno prepoznatljivom silanskom vezom. U razvoju kompozitnih materijala, iznimno mjesto pripada Michael G. Buonocoreu, koji je predložio jetkanje caklinske povrÅ”ine ortofosfornom kiselinom, Rafael L. Bowenu, koji je stvorio kompozitnu smolu i Nobuo Nakabayashiu, koji je predložio hibridizaciju dentinskog supstrata i tako ostvario promociju adhezije pomoÄu infiltracije monomera u zubnu strukturu. Kompozitni materijali sastoje se od tri temeljna dijela: organske smolaste matrice i odgovarajuÄeg inicijatora polimerizacije, anorganskog punila te svezujuÄeg sredstva.
Kompozitni materijali razvili su se primarno za ispune prednjih i stražnjih zubi, ali se materijali sliÄnog sastava danas koriste za iznimno puno indikacija: peÄaÄenje fisura i jamica, adhezijsko cementiranje keramiÄkih 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 nadograÄuju i imaju znatno usavrÅ”ena fiziÄko-mehaniÄka svojstva u odnosu na prethodne generacije, poglavito tvrdoÄu, ÄvrstoÄu, elastiÄnost, otpornost na savijanje, kidanje, torziju i troÅ”enje. MeÄutim, kako križno povezivanje u mrežu tijekom polimerizacije dovodi do volumetrijskog skupljanja, a posljediÄno i polimerizacijskog stresa koji može u znaÄajnoj mjeri utjecati na stvaranje rubne pukotine i kompromitaciju trajnosti restorativnog zahvata, kompenzacija stresa predstavlja najveÄi znanstveni i kliniÄki izazov.
BuduÄnost kompozitnih materijala ogleda se u nekoliko smjerova. Prvi je iznalaženje niskoskupljajuÄih ili ekspandirajuÄih kompozitnih materijala, a drugi optimizacija kompozitnih materijala temeljenih na amorfnom kalcijevom fosfatu, koji je direktni prekursor hidroksilapatita, osnovne gradbene jedinice zuba. Ostali pristupi ukljuÄuju inkorporaciju antibakterijskih agensa u kompozite te razvoj materijala sa samovezujuÄim svojstvima
MikrotvrdoÄa 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 mikrotvrdoÄu visoko-viskoznih i nisko-viskoznih bulk-fill kompozitnih smola i usporediti ih s konvencionalnim kompozitnim materijalima. Äetiri 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 Äetiri 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. MikrotvrdoÄa svakog materijala na povrÅ”ini te na dubini od 2 i 4 mm je odreÄena po Vickersu. GSO je u prosjeku imao znaÄajno viÅ”e vrijednosti mikrotvrdoÄe od ostalih materijala (p<0,001). Niskoviskozni
kontrolni kompozit XF imao je sliÄne vrijednosti kao SDR, ali znaÄajno niže nego nego XB (p<0,001) i znaÄajno viÅ”e nego VBF (p<0,001). MikrotvrdoÄa visoko-viskoznih bulk-fill materijala je niža nego kod konvencionalnog kompozitnog materijala GSO. PovrÅ”inska mikrotvrdoÄa nisko-viskoznih materijala je opÄenito joÅ” niža. MikrotvrdoÄa svih testiranih materijala na dubini od 4 mm se ne razlikuje od njihovih povrÅ”inskih vrijednosti mikrotvrdoÄe. Dodatni sloj kompozita za prekrivanje nisko-viskoznih bulk-fill materijala je nužan zbog njihove male mikrotvrdoÄe
UÄinak dentinskih adheziva na uÄestalost 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 Ī¼g/mL, 0.5 Ī¼g/mL and 5 Ī¼g/mL) obtained from each of the tested materials. Genotoxicity was evaluated by micronucleus test. The Ļ2-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 Ī¼g/mL and 5 Ī¼g/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.StomatoloÅ”ki 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 genotoksiÄnog uÄinka 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 razliÄitim koncentracijama eluata (0,2 Ī¼g/mL, 0,5 Ī¼g/mL i 5 Ī¼g/mL) dobivenim iz ispitivanih materijala. Za procjenu genotoksiÄnosti koristio se mikronukleus test, dok se Ļ2-test koristio za statistiÄku analizu (p<0,05). Adhezivi pokazuju genotoksiÄan uÄinak u kulturi limfocita nakon jednosatnog tretiranja eluatom koncentracije 5 Ī¼g/mL. Nakon 24 h svi su ispitivani adhezivi pokazali genotoksiÄnost u koncentraciji 0,5 Ī¼g/mL i 5 Ī¼g/mL. Na temelju rezultata može se zakljuÄiti kako upotreba adheziva izaziva genotoksiÄni uÄinak u ljudskim limfocitima. ToksiÄni uÄinak poveÄava 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 (BluephaseĀ® 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 Äetiri bulk-fill kompozita ā Filtek One Bulk Fill (3M), Tetric PowerFill (Ivoclar Vivadent, Schaan, LihtenÅ”tajn), Tetric PowerFlow (Ivoclar Vivadent) i SDR Plus (Dentsply, Konstanz, NjemaÄka). Kompozitni uzorci promjera 9 mm i visine 2 mm (n = 6) polimerizirani su svjetlom visokoga intenziteta (BluephaseĀ® 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 statistiÄki obraÄeni s pomoÄu jednosmjerne ANOVA-e uz Tukeyevu post-hoc korekciju. RazliÄiti protokoli polimerizacije za isti ma-terijal usporeÄeni su t-testom (p < 0,05). Rezultati: Trosekundni protokol polimerizacije povisio je to-pljivost svih materijala. Filtek One Bulk Fill pokazao je znaÄajno najviÅ”e 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 viÅ”e dana imerzije uzoraka. Zaklju-Äak: Brza polimerizacija prouzroÄila je poveÄanje topljivosti Å”to 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 poveÄane topljivosti koja premaÅ”uje ograniÄenja standarda ISO 4049:2009
Mjerna toÄnost stomatoloÅ”kih 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 Friedmanās 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.NeodgovarajuÄi intenzitet svjetlosti polimerizacijskih ureÄaja može ugroziti kvalitetu i dugotrajnost stomatoloÅ”kih kompozitnih restoracija. Kako bi se oÄuvala optimalna snaga polimerizacijskih ureÄaja neophodna je redovita kontrola. Svrha ovoga ispitivanja bila je usporediti dva radiometra u toÄnosti mjerenja intenziteta svjetlosti fotopolimerizacijskih ureÄaja uzimajuÄi u obzir vrijeme mjerenja. Mjerenja intenziteta svjetlosti 16 halogenih i 8 LED polimerizacijskih lampa provedena su pomoÄu tri ureÄaja na poÄetku iluminacije, te nakon 10 i 40 sekunda. KoriÅ”tena su dva ruÄna radiometra: Bluephase meter (BM) i Cure Rite (CR), dok je integrirajuÄa sfera (IS) predstavljala referentni ureÄaj. Podaci su statistiÄki analizirani pomoÄu Friedmanova testa i Wilcoxonova signed-rank testa (p<0.05). Vrijednosti izmjerene pomoÄu BM na poÄetku i nakon 10 sekunda bile su znaÄajno viÅ”e od onih izmjerenih pomoÄu IS, dok je CR pokazao viÅ”e vrijednosti nakon 10 i 40 sekunda. Oba komercijalno dostupna radiometra pokazala su tendenciju prikazivanja viÅ”ih vrijednosti intenziteta svjetlosti LED i halogenih polimerizacijskih ureÄaja u usporedbi s referentnim ureÄajem. Vrijeme mjerenja ima utjecaja na oÄitanje intenziteta svjetlosti. Zagrijavanje radiometara je predloženo kao moguÄe objaÅ”njenje 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 (Ceramā¢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 (nā=ā40), 20 min and 72 h after polymerization. Linear PS and Vickers microhardness (nā=ā40) were also evaluated. The results were analyzed by paired samples t test, ANOVA, and one-way repeated measures ANOVA with Student-Newman-Keuls or Tukeyās post-hoc test (Pā=ā0.05). RESULTS: The addition of barium fillers significantly increased the DC (20 min) (75.84āĀ±ā0.62%) in comparison to 0-ACP (73.92āĀ±ā3.08%), but the addition of silica fillers lowered the DC (71.00āĀ±ā0.57%). Ceramā¢X had the lowest DC (54.93āĀ±ā1.00%) and linear PS (1.01āĀ±ā0.24%) but the highest HV (20.73āĀ±ā2.09). PS was significantly reduced (Pā<ā0.010) in both Ba-ACP (1.13āĀ±ā0.25%) and Si-ACP (1.17āĀ±ā0.19%) compared to 0-ACP (1.43āĀ±ā0.21%). HV was significantly higher in Si-ACP (12.82āĀ±ā1.30) than in 0-ACP (10.54āĀ±ā0.86) and Ba-ACP (10.75āĀ±ā0.62) (Pā<ā0.010). 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 koliÄina aerobnih, anaerobnih i ukupnog broja bakterijskih kolonija nakon kemijsko-mehaniÄke 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 koriÅ”ten je isti broj jednokorijenskih zuba (n=23). Za mikrobioloÅ”ku analizu uzeta su tri brisa ā neposredno prije (B1) mehaniÄke instrumentacije i irigacije 2,5-postotnom otopinom natrijeva hipoklorita i poslije toga postupka (B2) te nakon kemijsko-mehaniÄke obrade i dodatnog tretmana korijenskog kanala ozonom (B3). Brisevi su uzeti sterilnim papirnatim Å”tapiÄima, bakterije su kultivirane, a rezultati su interpretirani nakon 14 dana koristeÄi se sustavom API 20A. Podaci su analizirani testom Wilcoxon Signed Rank. Rezultati: Razlike izmeÄu 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 statistiÄki znaÄajni (p<0,05). ZakljuÄak: Obje metode imale su dobar uÄinak i smanjile su broj bakterija prisutnih u korijenskom kanalu. Dodatnim tretmanom ozonom, nakon kemijsko-mehaniÄke obrade, joÅ” se smanjio broj aerobnih i anaerobnim bakterija, u usporedbi s mjerenjima neposredno prije kemijsko-mehaniÄke obrade i nakon nje. Kako bi se smanjio i reducirao broj bakterija, u svakodnevnoj se uporabi u kliniÄkoj praksi preporuÄuje 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 remineralizirajuÄi sastojak dodana su inertna punila kako bi se smanjilo njihovo polimerizacijsko skupljanje i poboljÅ”ala mehaniÄka svojstva. Svrha: Svrha istraživanja bila je ispitati utjecaj dodavanja razliÄitih 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 Å”est koji su sadržavali 40 posto ACP-a, 5 posto ili 10 posto neaktivnih punila i 55 posto ili 50 posto smole. U kompozitne materijale ukljuÄena su silika-punila (12nm; 4 ā 6% silanizacija) te barijeva (0,77Ī¼m; 6% silanizacija) ili stroncijeva staklena punila (0,99Ī¼m; 3,2% silanizacija). Nanohibridni kompozit CeramX (Dentsply DeTrey, NjemaÄka) takoÄer je služio kao kontrolni materijal. Kompozitni uzorci (10/ispitnoj skupini) polimerizirani su 40 sekundi ureÄajem Bluephase C8 (Ivoclar Vivadent, Liechtenstein). Stupanj polimerizaciuje odreÄen 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 Å”tetno 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 oÄekivalo, ACP-kontrola s najmanjim volumenom punila zadržala je najviÅ”i SP (75,38% i 76,05%), a CeramX je imao statistiÄki najniži (56,87% i 57,97%). ZakljuÄak: Iako je primjesa odreÄenih punila pridonijela smanjenju stupnja polimerizacije ACP-kompozitnih smola, uzimajuÄi u obzir da je ipak uvelike nadmaÅ”en stupanj polimerizacije komercijalno dostupnog kontrolnog materijala, može se zakljuÄiti da neÄe izazvati neželjene uÄinke 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 (0.77Ī¼m; 6% silanization) or strontium glass fillers (0.99Ī¼m; 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