Dental status of adults in the eastern region of Republika Srpska

Introduction. A significant change in frequency and characteristics of oral diseases in developed countries has been detected recently. The aim of this study was to determine the dental status of teeth in adults in the eastern region of Republika Srpska and to determine possible difference in the prevalence of dental diseases according to the demographic characteristics. Materials and Methods. The study included 182 respondents aged 35-44 years and 185 respondents aged 65-74 years, selected randomly from four municipalities in the eastern region of Republika Srpska. Dental examinations were conducted according to the standards and criteria developed by the World Health Organization. Dental status, determined by DMFT index, was analyzed according to the gender and place of residence (urban/rural). Results. The mean DMFT index was 20.2 in the age group 35-44 years and 28.5 in subjects aged 65-74 years. The dominant component of the index in both studied groups was the number of extracted teeth. For subjects aged 65-74 years from rural areas a significantly higher DMFT index as compared to the residents in urban regions (p<0.05) was reported. Females had fewer caries lesions (p<0.05) and greater number of restored (p<0.01) teeth as compared to male respondents in the age group 35-44 years. On the other hand, in the older population study group, females had lower number of restored teeth (p<0.01), higher number of missing teeth (p<0.01) and higher DMFT index (p<0.2001) as compared to males. Conclusion. The present results indicate that the prevalence of caries in adults in the eastern region of Republika Srpska is very high

SEM analiza kvaliteta adhezivne veze glasjonomercementnih restauracija

Introduction. Lack of proper adhesion is one of the most common problems in modern restorative dentistry and the main cause of the occurrence of microcracks at the interface between materials and hard dental tissue. The aim of this study was to assess the quality of bond between two types of glass-ionomer cement (GIC) class V restorations and hard dental tissues by SEM. Materials and Methods. This clinical study included 20 intact teeth (premolars and molars) recently extracted for orthodontic reasons in patients of both genders and different ages. Class V cavity with rounded walls was prepared on vestibular and oral surfaces of all teeth (3x2x2 mm). Conventional GIC Fuji II was applied on vestibular surface of teeth whereas on oral surface resin-reinforced glass ionomer Fuji II LC was placed. The bond between fillings and hard dental tissue was assessed by SEM. Results. Both materials showed microcracks, however, microleakage was lower with Fuji II LC than with Fuji II. Microcracks were observed in 65% of cases (13 restorations) restored with GIC Fuji II and 35% (7 fillings) restored with GIC Fuji II LC. The size of microcracks for Fuji II LC was 9 μm while this value for Fuji II was 17 μm. The difference was statistically significant. Conclusion. Better bond between material and hard dental tissue was achieved with the material of new generation, resin modified GIC.Uvod. Nedostatak odgovarajuće adhezivnosti je jedan od najčešćih problema u savremenoj restaurativnoj stomatologiji i glavni uzrok nastanka mikropukotine na spoju materijala i tvrdih zubnih tkiva. Cilj ovog rada je bio da se SEM (skening-elektronska mikroskopija) analizom proveri kvalitet veze dve vrste glasjonomercementnih (GJC) restauracija za tvrda zubna tkiva kod kaviteta V klase. Materijal i metode rada. Kliničko istraživanje je obuhvatilo 20 sveže ekstrahovanih intaktnih zuba (premolari i molari), odstranjenih iz ortodontskih razloga kod pacijenata oba pola i različite starosti. Na svim zubima su sa vestibularne i oralne strane urađene jednopovršinske preparacije V klase adhezivnog tipa sa zaobljenim zidovima kaviteta (dimenzija 3×2×2 mm). Sa vestibularne strane primenjen je klasični GJC Fuji II, a sa oralne smolom ojačani GJC Fuji II LC. Kvalitet veze između ispuna i zubnih tkiva je procenjivan SEM analizom. Rezultati. Dobijeni nalazi su pokazali da je kod oba materijala zabeležena mikropukotina i da je stepen mikrocurenja kod Fuji II LC bio manji nego kod Fuji II. Kod zuba restaurisanih sa GJC Fuji II mikropukotina je uočena u 65% slučajeva (13 ispuna), a kod zuba restaurisanih sa GJC Fuji II LC u 35% slučajeva (sedam ispuna). SEM analizom je utvrđena srednja vrednost mikropukotine za Fuji II LC od 9 µm, dok je ova vrednost za Fuji II bila 17 µm. Razlika je bila statistički značajna. Zaključak. Na osnovu rezultata istraživanja može se zaključiti da je bolji kvalitet veze ostvaren primenom materijala novije generacije, odnosno primenom GJC modifikovanih smolom

Синтетски пут за добијање 1,2,3,4-тетрахидрохиноксалинскo/пиперидинског трицикличног система

The synthetic route toward novel tricyclic, nitrogen-containing system is disclosed. Three novel compounds possessing structural features of 1,2,3,4-tetrahydroquinoxaline and decahydropyrido[3,4-b]pyrazine are synthesized starting from readily available precursors in six or seven steps, of which the last three or four steps respectively are diastereoselective. Key reaction steps include N-acylation, Hofmann rearrangement and ring-closing Buchwald– Hartwig reaction. Compounds trans-8, cis-12 and trans-12 are synthesized in order to prove that this novel, tricyclic system can be functionalized with various groups. Synthetic significance of this heterocyclic system lies in the possibility for the orthogonal functionalization of three different amino groups, allowing fine structural tuning.У овом раду представљена је синтеза новог трицикличног система који садржи азот. Три нова једињења код којих су комбиноване структурне карактеристике 1,2,3,4-тетрахидрохиноксалина и декахидропиридо[3,4-b]пиразина, добијена су полазећи од лако доступних прекурсора, у шест или седам фаза од којих су последње три или четири, редом, диастереоселективне. Кључне синтетичке трансформације укључују N-ациловање, Hofmann премештање и интрамолекулску Buchwald–Hartwig реакцију, као фазу у којој долази до циклизације. Једињења trans-8, cis-12 и trans-12 су синтетисана како би се представила могућност функционализације новог трицикличног система. Синтетички значај новог хетероцикличног система представљен је у могућности ортогоналне функционализације три различите амино групе, чиме се може постићи фино подешавање структуре

Antimikrobna aktivnost novosintetisanog endodontskog nanomaterijala na bazi kalcijum-aluminata

Introduction Materials used for root canal obturation and root perforation are expected to have, in addition to preventing apical, lateral and coronary leakage, antimicrobial effects on microorganisms that are not accessible to chemomechanical instrumentation and intra-canal medications. The aim of this study was to evaluate the antimicrobial effect of a novel calcium aluminate-based endodontic nanostructured biomaterial (ALBO-MCCA) using agar diffusion test. Material and methods the two materials were tested in the study. The nanostructured calcium aluminate was synthesized by the hydrothermal sol-gel method from individual components of calcium aluminate (CaOxAl2 O3 ), calcite (CaCO3 ) and barium sulfate (BaSO4 ) as radiocontrast agent in the ratio of 2:2:1 according to V. Jokanovic's recipe. The other used material was calcium silicate MTA Angelus (Londrina, Brazil). The antimicrobial effect was assessed using agar diffusion test. Standard strains of Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, cultured on blood Mueller-Hinton agar and Candida albicans cultivated on Sabouraud Dextrose Agar, were used as test microorganisms. Results the best antimicrobial effect after 24 h both materials showed against S. aureus. The mean values of the growth inhibition zone for ALBO MCCA were 5.7 ± 0.25 mm and MTA 6.2 ± 0.4 mm. The ALBO MCCA material showed slightly stronger antibacterial effect against E. coli compared to MTA (p lt 0.05), whereas none of the materials showed antibacterial effect against E. faecalis. Conclusion the ALBO MCCA material showed certain antibacterial effect on Escherichia coli, Staphylococcus aureus and Candida albicans that was comparable to antibacterial effect of MTA.Uvod Od materijala koji se koriste za opturaciju kanala korena i perforacija na korenu se očekuje da pored sprečavanja apikalnog, lateralnog i koronarnog curenja, poseduju i antimikrobno delovanje na mikroorganizme, koji nisu dostupni hemomehaničkoj obradi i intrakanalnim medikamentima. Cilj ovog istraživanja je bio da se testom difuzije u agaru proceni antimikrobni efekat novog endodontskog nanostrukturnog biomaterijala na bazi kalcijum-aluminata (ALBO-MCCA). Materijal i metode U istraživanju su korišćena dva materijala. Nanostrukturni kalcijum-aluminat je sintetisan hidrotermalnom sol-gel metodom od pojedinačnih komponenata kalcijum-aluminata (CaO·Al2 O3 ), kalcita (CaCO3 ) i barijum-sulfata (BaSO4 ) kao rendgen-kontrastnog sredstva u odnosu 2 : 2 : 1 prema recepturi V. Jokanovića. Drugi korišćeni materijal je kalcijum-silikatni MTA Angelus (Londrina, Brazil). Antimikrobni efekat je ispitivan testom difuzije u agaru. Kao test mikroorganizmi korišćeni su standardni sojevi Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, koji su kultivisani na krvnom agaru MuellerHinton, dok je C. albicans kultivisana na agaru Sabouraud Dextrose. Rezultati Najbolji antimikrobni efekat nakon 24 h oba materijala su pokazala prema bakteriji S. aureus. Izmerene prosečne vrednosti zone inhibicije rasta iznosile su kod ALBO-MCCA (5,7 ± 0,25 mm), odnosno kod MTA (6,2 ± 0,4 mm). Materijal ALBO-MCCA je pokazao nešto veći antibakterijski efekat prema bakteriji E. coli u odnosu na MTA (p lt 0,05), dok prema bakteriji E. faecalis nijedan materijal nije ispoljio antibakterijski efekat. Zaključak Materijal ALBO-MCCA je ispoljio određeni antibakterijski efekat na bakterije Escherichia coli, Staphylococcus aureus i Candida albicans komparabilan sa antibakterijskim efektom MTA

Prevalencija bakterija Enterococcus faecalis i Porphyromonas gingivalis u inficiranim kanalima korena zuba i njihova osetljivost na endodontsko lečenje - molekularna studija

Introduction Because apical periodontitis is recognizably an infectious disease, elimination or reduction of intracanal bacteria is of utmost importance for optimum treatment outcome. Objective The prevalence of Enterococcus faecalis and Porphyromonas gingivalis in infected root canals was studied Also, the effect of endodontic therapy by using intracanal medicaments, calcium hydroxide paste (CH) or gutta-percha points containing calcium hydroxide (CH-GP) or chlorhexidine (CHX-GP) on these microorganisms was assessed by polymerase chain reaction (PCR) assay. Methods Fifty-one patients with chronic apical periodontitis were randomly allocated in one of the following groups according to the intracanal medicament used: CH, CH-GP and CHX-GP group. Bacterial samples were taken upon access (S1), after chemomechanical instrumentation (S2) and after 15-day medication (S3). PCR assay was used to detect the presence of selected bacteria. Results E. faecalis was detected in 49% (25/51) and P. gingivalis in 17.6% (9/51) of the samples. Samples which showed no bacterial presence at S1 were excluded from further analysis. Overall analysis of all 29 samples revealed significant differences between S1 and S2 (p lt 0.001), S2 and S3 (p lt 0.05), and S1 and S3 (p lt 0.001). When distinction was made between the intracanal medications, there was a significant difference in the number of PCR positive samples between S1 and S2, S1 and S3, but not between S2 and S3 samples. Conclusion E. faecalis is more prevalent than P. gingivalis in primary endodontic infection. Intracanal medication in conduction with instrumentation and irrigation efficiently eliminates E. faecalis and P. gingivalis from infected root canals.Uvod Budući da je apeksni parodontitis oboljenje koje nastaje usled postojanja infekcije, za postizanje optimalnog ishoda lečenja najznačajnije je uklanjanje bakterija iz kanala korena zuba ili barem smanjenje njihovog broja. Cilj rada Cilj ovog rada je bio da se ispita prevalencija bakterija Enterococcus faecalis i Porphyromonas gingivalis u inficiranim kanalima korena zuba i ustanovi efekat endodontskog lečenja primenom intrakanalnih medikamenata - kalcijum-hidroksidne suspenzije (CH), gutaperka-poena na bazi kalcijum-hidroksida (CH-GP) ili gutaperka-poena na bazi hlorheksidina (CHX-GP) - na ove mikroorganizme metodom lančane reakcije polimerizacije (PCR). Metode rada Istraživanjem je obuhvaćena 51 osoba koja je imala zub s hroničnim apeksnim parodontitisom. Ispitanici su metodom slučajnog uzorka svrstani u tri grupe u zavisnosti od vrste primenjenog intrakanalnog medikamenta (CH, CH-GP i CHX-GP). Bakterijski uzorci iz kanala korena sakupljani su pri inicijalnom ulasku u kanal korena (S1), posle hemomehaničke obrade (S2) i posle petnaestodnevnog lečenja (S3). PCR analiza je korišćena za određivanje prisustva ispitivanih bakterija. Rezultati E. faecalis je izolovan iz 25 (49%) uzoraka, a P. gingivalis iz devet (17,6%). Uzorci u kojima nisu nađene bakterije u S1 fazi isključeni su iz dalje analize. Analiza svih 29 uzoraka je ukazala na statistički značajnu razliku između S1 i S2 uzoraka (p lt 0,001), S2 i S3 (p lt 0,05) i S1 i S3 (p lt 0,001). Kada se uzme u obzir vrsta intrakanalnog medikamenta, statistički značajna razlika u broju PCR-pozitivnih uzoraka zabeležena je između S1 i S2, S1 i S3, ali ne i između S2 i S3. Zaključak U primarnoj endodontskoj infekciji E. faecalis se češće javlja od P. gingivalis. Intrakanalna medikacija zajedno s instrumentacijom i irigacijom efikasno uklanja E. faecalis i P. gingivalis iz inficiranih kanala korena

Dental pulp pain in young and postmenopausal women: A pilot study

Introduction This pilot study was aimed to compare pulpal pain provoked by electrical and thermal (cold) stimuli in healthy young women during various phases of menstrual cycle and postmenopausal women. Material and methods The study included 20 regularly menstruating healthy women and 20 postmenopausal women. Electrical (electrical pulp tester) and cold (refrigerant spray) stimuli were performed on mandibular central incisors, twice in regularly menstruating (menstrual and luteal phases) and once in postmenopausal women. Results were expressed as pain threshold values for electrical pulp stimulation (0-80 units) and pain intensity scores (visual numeric scale, from 0 to 10) for cold stimulation. Results In young women, higher pain electrical threshold (p=0.484) and pain sensitivity score (p=0.015) were observed in luteal in comparison to menstrual phase. In postmenopausal women, electrical pain threshold was significantly higher while pain intensity score was significantly lower than in young women, regardless of the menstrual phase and painful stimuli. Conclusion Lower responsiveness to dental pulp pain was obtained in young women in luteal phase and postmenopausal women

Radiološka procena kvaliteta punjenja kanala korena endodontski lečenih zuba na studentskim vežbama

Introduction. The main goal of obturation is prevention of reinfection of the root canal system and consequently appearance of periapical lesion. Epidemiological studies have confirmed high prevalence of periapical lesions in endodontically treated teeth with inadequate root canal fillings. The aim of this study was to assess the quality of root canal fillings in teeth treated at students' practical sessions. Iatrogenic errors during endodontic interventions were also assessed. Methods. Two hundred dental records of the patients treated by students in the study program Dentistry at the School of Medicine in Foca during the academic year 2010/2011 were randomly chosen. The length and homogeneity of the fillings or the presence of iatrogenic errors were recorded. A root canal filling was considered adequate if it had correct length and homogeneity in the absence of iatrogenic errors. Two students' curricula V1 and V2 were evaluated for the treatment outcome. Results. Out of 128 endodontically treated teeth, adequate length of the canal filling to the physiological apex was observed in 57% of teeth, homogeneity in 78.9%, while both of these criteria were satisfied in 66 teeth (51.6%). Better quality of root canal fillings was achieved by students of the study curricula V2 and the difference between these two programs was significant (p lt 0.05). Better quality of root canal fillings in both study programs was recorded for incisors and canines as compared to premolars. Conclusion. The quality of endodontic treatment performed by students was considered adequate in 51.6% of cases. The type of curriculum for endodontic course had a significant impact on the quality of endodontic treatment performed by students.Uvod. Opturacija kanala korena zuba vrši se radi prevencije ponovne infekcije kanalnog sistema i obezbeđivanja uslova za efikasno ozdravljenje periapeksnog tkiva. Epidemiološke studije su ukazale na visoku stopu prevalencije periapeksnih promena kod endodontski lečenih zuba sa neodgovarajućim punjenjem kanala. Cilj rada bio je da se proveri kvalitet punjenja kanala korena endodontski lečenih zuba na studentskim vežbama i ustanove lekarske greške nastale tokom endodontske intervencije. Materijal i metode rada. Za potrebe istraživanja metodom slučajnog uzorka odabrano je 200 kartona pacijenata kojima je vršen endodontski tretman na studentskim vežbama koje su u okviru studijskog programa Stomatologija izvođene na Medicinskom fakultetu u Foči tokom 2010/2011. školske godine. Parametri posmatranja bili su dužina i homogenost punjenja kanala i postojanje lekarskih grešaka tokom zahvata. Adekvatnim se smatralo punjenje kanala koje ima odgovarajuću dužinu i homogenost i bez lekarskih grešaka. Analizirana su dva studentska programa iz oblasti endodoncije (V1 i V2) i utvrđen ishod lečenja obolelih zuba. Rezultati. Od 128 endodontski lečenih zuba, odgovarajuća dužina punjenja kanala do fiziološkog suženja utvrđena je u 57% uzoraka, homogenost u 78,9% uzoraka, dok su oba ova kriterijuma bila zadovoljena kod ukupno 66 zuba (51,6%). Kvalitetnije punjenje kanala korena uradili su studenti programa V2, a razlika između dva studentska programa bila je statistički značajna (p lt 0,05). Kvalitetna opturacija kanala u oba studijska programa zabeležena je kod sekutića i očnjaka u odnosu na premolare. Zaključak. Kvalitet endodontskog lečenja na studentskim vežbama bio je odgovarajući u nešto više od polovine slučajeva. Kurikulum iz oblasti endodoncije ima značajan uticaj na kvalitet endodontskog lečenja na studentskim vežbama

Stanje parodoncijuma osoba obolelih od dijabetes melitusa u odnosu na nivo glikoziliranog hemoglobina i oralnu higijenu

Introduction. It has been known that periodontitis is one of the most common oral diseases in patients having diabetes mellitus (DM). The aim of this study was to examine the influence of glycosylated hemoglobin (HbA1c) level and the level of oral hygiene on periodontal status of patients suffering from DM. Material and Methods. The research included 50 people with type 2 DM randomly selected. Based on values of HbA1c, patients were divided into two groups: well controlled DM (HbA1c≤8.5%) and poorly controlled DM (HbA1c>8.5%). Patients with poorly and well controlled DM were further grouped into subgroups depending on the level of oral hygiene. For each patient, during the clinical examination, periodontal parameters were determined: plaque index (PI), sulcus bleeding index (SBI), the level of junctional epithelium (LJE) and periodontal pocket depth (PPD). Results. The results showed that patients with well controlled disease and good oral hygiene had lower values of the examined periodontal parameters (SBI and PPD) then patients with poorly controlled DM and worse oral hygiene (p lt 0.01 for SBI, p lt 0.05 for PPD). Conclusion. The results of this study indicate the important role of oral hygiene for periodontal status of patients with DM.Uvod. Parodontopatija je jedno od najčešćih oboljenja oralne regije kod osoba obolelih od dijabetes melitusa (DM). Cilj ovog istraživanja je bio da se ispita uticaj nivoa glikoziliranog hemoglobina (HbA1c) i stepena oralne higijene na stanje parodoncijuma bolesnika sa DM. Materijal i metode rada. Ispitano je 50 osoba sa DM tip 2 koje su odabrane metodom slučajnog uzorka. Na osnovu vrednosti HbA1c, ispitanici su svrstani u dve grupe: prvu grupu su činili bolesnici koji su dobro kontrolisali DM (HbA1c≤8,5%), a drugu bolesnici s loše kontrolisanim DM (HbA1c>8,5%). Ispitanici dve grupe su dalje podeljeni u podgrupe u zavisnosti od stepena oralne higijene. Svakom bolesniku su prilikom kliničkog pregleda određene vrednosti parodontalnih parametara: plak-indeksa (PI), indeksa krvarenja gingive (IKG), nivoa pripojnog epitela (NPE) i dubine parodontalnog džepa (DPDŽ). Rezultati. Dobijeni rezultati su pokazali da su kod bolesnika sa dobro kontrolisanim oboljenjem i dobrom oralnom higijenom vrednosti ispitivanih parodontalnih parametara (IKG i NPE) niže nego kod bolesnika s loše kontrolisanim DM i lošijom oralnom higijenom (p lt 0,01 za IKG; p lt 0,05 za NPE). Zaključak. Rezultati ovog istraživanja ukazuju na značajnu ulogu oralne higijene na stanje parodoncijuma osoba sa DM

Uticaj različitih oblika kalcijum-hidroksida i hlorheksidina kao interseansnih medikamenata na ishod endodontskog lečenja zuba sa hroničnim periapeksnim lezijama

Introduction/Objective The aim of this study was to determine clinical and radiographic periapical healing of teeth with apical periodontitis treated with different formulations of calcium hydroxide (CH) - paste (CH-paste) and gutta-percha points (CH-GP) - as well as those of chlorhexidine (CHX) - gel (CHXgel) and gutta-percha points (CHX-GP) -12 months after therapy. Methods Eighty patients with chronic apical periodontitis were randomly allocated to four treatment groups according to the intracanal medicament used: CH-paste, CH-GP, CHX-gel, and CHX-GP group. Seventy-eight patients were analyzed clinically and radiographically 12 months postoperatively. The periapical index (PAI) was used for the radiographic evaluation of treatment. Results Overall outcome was classified according to radiographic evaluation only, since clinical success was observed in all the patients. In all the groups, significant reduction in PAI scores was observed (p lt 0.001). The proportions of healed teeth (PAI ≤ 2) were 73.7%, 60%, 68.4%, and 65% in CH-paste, CH-GP, CHX-gel and CHX-GP group, respectively, with no significant differences between the groups. Conclusion The results suggest that there are no differences between investigated CH- and CHX-delivery systems regarding treatment outcome of teeth with apical periodontitis.Uvod/Cilj Cilj ovog istraživanja je bio da se ispita klinički i radiografski ishod lečenja zuba sa apeksnim periodontitisom 12 meseci posle završene terapije i primene različitih oblika kalcijum-hidroksida (KH): pasta (KH-pasta) i gutaperka poeni (KH-GP) i hlorheksidina (HH): gel (HH-gel) i gutaperka poeni (HH-GP). Metode Randomizovano je 80 ispitanika sa hroničnim periapeksnim lezijama u četiri grupe na osnovu vrste korišćenog interseansnog medikamenta: KH-pasta, KH-GP, HH-gel i HH-GP. Dvanaest meseci posle završenog lečenja pregledano je 78 ispitanika i urađeni su retroalveolarni snimci. Za procenu radiografskog uspeha lečenja korišćen je periapikalni indeks (PI). Rezultati Ishod lečenja je klasifikovan na osnovu radiološkog nalaza jer je kod svih ispitanika zabeležen klinički uspeh lečenja. U svim ispitivanim grupama je zabeleženo značajno smanjenje vrednosti PI (p lt 0,001). Izlečenje (PI ≤ 2) uočeno je kod 73,3% zuba u grupi KH-pasta, 60% u KH-GP grupi, 68,4% u grupi HH-gel i kod 65% zuba u grupi HH-GP, pri čemu razlike između grupa nisu bile statistički značajne. Zaključak Rezultati ovog istraživanja pokazuju da ne postoji razlika u ishodu lečenja zuba sa apeksnim periodontitisom posle primene ispitivanih oblika KH i HH

Residual monomer content determination in some acrylic denture base materials and possibilities of its reduction

Background/Aim. Polymethyl methacrylate is used for producing a denture basis. It is a material made by the polymerization process of methyl methacrylate. Despite of the polymerization type, there is a certain amount of free methyl methacrylate (residual monomer) incorporated in the denture, which can cause irritation of the oral mucosa. The aim of this study was to determine the amount of residual monomer in four different denture base acrylic resins by liquid chromatography and the possibility of its reduction. Methods. After the polymerization, a postpolymerization treatment was performed in three different ways: in boiling water for thirty minutes, with 500 W microwaves for three minutes and in steam bath at 22º C for one to thirty days. Results. The obtained results showed that the amount of residual monomer is significantly higher in cold polymerizing acrylates (9.1-11%). The amount of residual monomer after hot polymerization was in the tolerance range (0.59- 0.86%). Conclusion. The obtained results denote a low content of residual monomer in the samples which have undergone postpolymerization treatment. A lower percent of residual monomer is established in samples undergone a hot polymerization