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Tooth agenesis is common dentofacial malformation in humans. Its etiology is still not clear. Hypodontia has been regarded as a multifactorial condition influenced by gene function, environmental interaction and developmental timing. More than 300 genes have been related with patterning, morphogenesis and cell differentiation in teeth. According to data WNT10A gene is considered to have an important role in odontogonesis. The aim of this study was to show mutation status in WNT10A gene in a family with two members with diagnosis of hypodontia/oligodontia. In the reported family (father, mother, son, daughter) children were diagnosed with congenital tooth agenesis (son-2 teeth, daughter-11 teeth), while parents negated congenital absence of teeth. We identified a heterozygous missense mutation, c.682T>A (p.Phe228Ile) within the exon 3 of WNT10A in mother and father and the same homozygous mutation was detected in the same region of WNT10A gene in daughter and son. Observed differences in our study, from no symptoms to mild/severe hypodontia, could be the consequence of genetic influence of c.682T>A(p.Phe228Ile) mutation, but also the contribution of many environmental factors during odontogenesis., Urođeni nedostatak zuba predstavlja jednu od najčešćih dentofacijalnih anomalija kod čoveka. Etiologija hipodoncije i dalje nije potpuno definisana i smatra se da su za njenu etiologiju odgovorni brojni genetski i sredinski faktori koji deluju u različitim fazama razvoja zuba. Preko 300 gena povezuje se sa morfogenezom i ćelijskom diferencijacijom u toku razvoja zuba, a prema podacima WNT10A gen je jedan od gena koji ima veoma bitnu ulogu u kontroli odontogeneze. Cilj ovog rada bio je da se prikaže mutacioni status WNT10A gena u porodici sa dijagnostikovanom hipodoncijom/oligodoncijom. U prikazanoj porodici (otac, majka, sin i ćerka) kod dva člana dijagnostikovan je urođeni nedostatak zuba (sin - dva zuba, ćerka - 11 zuba), dok kod roditelja ovaj nedostatak nije zabeležen. Kod svih članova porodice, u okviru egzona 3 WNT10A gena detektovana je mutacija c.682T>A (p.Phe228Ile). Kod majke i oca ova 'missense' mutacija je bila u heterozigotnom obliku, dok je kod sina i ćerke utvrđeno prisustvo iste mutacije u homozigotnom obliku. Zabeležene razlike u analiziranoj porodici, od odsustva simptoma do blage hipodoncije i izrazite oligodoncije, mogu biti posledica prisustva c.682T>A (p.Phe228Ile) mutacije, ali takođe i uticaja faktora sredine u toku odontogeneze.

Background/Aim: The aim of this study was to evaluate the efficacy of new rotary NiTi instrument XP-endo SHAPER (XPS) used with two irrigation protocols on the root canal cleaning in the apical area. Material and Methods: The research was conducted on 30 single-rooted teeth extracted for orthodontic reasons which were divided into the two groups. Instrumentation of the canals was conducted with XPS instrument and 2% solution of NaOCl was used as irrigant. Instrumentation in the first group was performed using a conventional continuous irrigation, in the second group, protocol of final irrigation was performed intermittently in 3 cycles. The SEM analysis of the apical third of the canal was performed on longitudinal root cross-section standardized photomicrography with a magnification of 2000X. Results: Results showed that a thicker smear layer was observed in the first group and with continuous irrigation protocol (2,10) in relation to the intermittent irrigation protocol in 3 cycles (1,96), but without significant differences. The walls of the root canal in the apical third of the samples of the second group were slightly cleaner (73.3%) in comparison with the teeth of the first group (64, 7%), but also without significant differences. Conclusions: The use of XPS and 2% solution of NaOCl in the root canal enables efficient cleaning of the apical third of tooth. The final irrigation protocol in three cycles improves the efficiency of the smear layer removal in the apical segment of the canal.

Aim: To examine the potential systemic toxicity of nanostructured materials based on calcium silicate and calcium aluminate, for potential application in Dentistry. Methodology: Twenty-four Albino Wistar rats aged 2 months were used as an in vivo animal model for subcutaneous implantation of the investigated materials, placed in polyethylene tubes. Thirty days after implantation, the livers of the rats were analysed and following histological and stereological parameters were evaluated for volume density of hepatocytes and blood sinusoids, number and numerical density of hepatocytes, surface of hepatocytes and their nucleuses, nucleocytoplasmic ratio and mitotic index of hepatocytes. Stereological measurements were achieved using Cavalieri's principle, with grid P2 and unbiased analysis. Additionally, immunohistochemistry studies were performed to further analyse changes in liver tissue. Several haematological and biochemical parameters of blood of experimental animals were also analysed, as well as local tissue reactions around the implants. Statistical analysis was performed using parametric (anova and t-test) and nonparametric tests (Kruskal–Wallis and Mann–Whitney U-test) depending on data distribution. Results: Implanted dental cements led to an increase in stereological and histological parameters in liver tissue compared to control rats. Although the investigated parameters mostly showed significant differences between control and experimental animals, the liver tissue of the experimental animals did not have visible signs of pathological changes. This was supported by the analysis of blood parameters which were not significantly different between control and experimental animals. Also, the subcutaneous tissues had minimal inflammatory reactions. Immunohistochemistry studies revealed that nanostructured materials induced proliferation of hepatocytes, but that the immunological response to the materials was not strong enough to induce proliferation of immunore

Aim To examine the potential systemic toxicity of nanostructured materials based on calcium silicate and calcium aluminate, for potential application in Dentistry. Methodology Twenty-four Albino Wistar rats aged 2 months were used as an in vivo animal model for subcutaneous implantation of the investigated materials, placed in polyethylene tubes. Thirty days after implantation, the livers of the rats were analysed and following histological and stereological parameters were evaluated for volume density of hepatocytes and blood sinusoids, number and numerical density of hepatocytes, surface of hepatocytes and their nucleuses, nucleocytoplasmic ratio and mitotic index of hepatocytes. Stereological measurements were achieved using Cavalieri's principle, with grid P2 and unbiased analysis. Additionally, immunohistochemistry studies were performed to further analyse changes in liver tissue. Several haematological and biochemical parameters of blood of experimental animals were also analysed, as well as local tissue reactions around the implants. Statistical analysis was performed using parametric (anova and t-test) and nonparametric tests (Kruskal-Wallis and Mann-Whitney U-test) depending on data distribution. Results Implanted dental cements led to an increase in stereological and histological parameters in liver tissue compared to control rats. Although the investigated parameters mostly showed significant differences between control and experimental animals, the liver tissue of the experimental animals did not have visible signs of pathological changes. This was supported by the analysis of blood parameters which were not significantly different between control and experimental animals. Also, the subcutaneous tissues had minimal inflammatory reactions. Immunohistochemistry studies revealed that nanostructured materials induced proliferation of hepatocytes, but that the immunological response to the materials was not strong enough to induce proliferation of immunoreact

Hypodontia (tooth agenesis) is one of the most common dental anomalies in humans that occurs either in non-syndromic forms or as a part of various syndroms. Hypodontia can be a result of nucleotide substitutions in genes that are involved in tooth morphogenesis, whose products are signal molecules and transcription factors that control gene expression in different phases of tooth morphogenesis (bud, cap and bell stage). Among many genes, WNT10A (with its expression in dental epithelial tissue) and RUNX2 gene (with its expression in mesenchimal tissue) have been singled out due to their key role in odontogenesis. Mutations of genes involved in odontogenesis can lead to changes in tooth morphology, structure and the number of teeth. The aim of this study was to examine the presence of potential mutations in RUNX2 and WNT10A genes, and to determine their inheritance path in patients with isolated (non-syndromic) forms of tooth agenesis. The second part of the investigation was aimed to compare tooth dimensions in hypodontia patients and healthy controls, in order to determine whether hypodontia / olygodontia is related to potential tooth size anomalies. Mutational status for RUNX2 and WNT10A genes was determined for 24 families. The sample included 72 subjects, 29 of which had clinically confirmed tooth agenesis. Mesiodistal tooth width was measured in 25 hypodontia patients and 25 healthy controls. Genetic mutations presence was confirmed by direct sequencing. Mesiodistal tooth width was measured on digitized study models using a computer software. Mutational analysis of WNT10A gene revealed the presence of two nucleotide substitutions in the exon 2 region (rs10180544, rs141074983) and three nucleotide substitutions in exon 3 (rs121908120, rs77583146, rs146902156). Mutational analysis of RUNX2 gene revealed four nucleotide substitutions in exon 3 (rs6921145, COSM1658842, rs759395776, rs768156797) and one in exon 4 (34 insC). Mutations in WNT10A gene were present in 52, Hipodoncija-urodjeni nedostatak zuba, predstavlja jednu od najĉešćih razvojnih anomalija kod ljudi, i moţe biti nesindromska i sindromska. Do razvoja hipodoncije moţe doći usled izmena u genima ukljuĉenim u morfogenezu zuba, a ĉiji produkti su signalni i transkripcioni faktori, odgovorni za vremenski programiranu ekspresiju gena u fazama pupoljka, kape i zvona. Iz palete gena ukljuĉenih u odontogenezu, zbog svog kljuĉnog znaĉaja izdvaja se WNT10A gen (eksprimiran u dentalnom epitelu), i RUNX2 gen (eksprimiran u mezenhimu). Mutacije gena povezanih sa odontogenezom mogu dovesti do izmena u morfologiji, broju i strukturi zuba. Ciljevi ove studije su bili da se ispita zastupljenost potencijalnih mutacija u RUNX2 i WNT10A genima i utvrdi njihov naĉin nasledjivanja kod izolovanih (nesindromskih) formi hipodoncije. Drugi deo istraţivanja odnosio se na uporedjivanje veliĉine zuba pacijenata sa urodjenim nedostatkom zuba i zdravih pacijenata kako bi se utvrdilo da li je hipodoncija/oligodoncija povezana sa eventualnim anomalijama veliĉine zuba . Mutacioni status RUNX2 i WNT10A gena, odreĊen je kod 24 porodice (72 ispitanika), pri ĉemu je kod 29 osoba, kliniĉki potvrdjena hipodoncija. Merenje meziodistalnih širina zuba je uradjeno kod 25 pacijenata sa uroĊenim nedostatkom zuba i 25 pacijenata kontrolne grupe. Prisustvo mutacija potvrĊeno je primenom tehnike direktnog sekvenciranja, dok je odreĊivanje meziodistalnih širina zuba uraĊeno primenom 3D skenera i merenjima na digitalnim modelima u kompjuterskom programu. Mutaciona analiza WNT10A gena, pokazala je prisustvo 2 nukleotidne izmene u regionu egzona 2 (rs10180544, rs141074983) i 3 izmene u egzonu 3 (rs121908120, rs77583146, rs146902156). Mutacionom analizom RUNX2 gena utvrĊeno je prisustvo 4 nukleotidne izmene u egzonu 3 (rs6921145, COSM1658842, rs759395776, rs768156797) i jedna nukleotidna izmena u regionu egzona 4 (34 insC)...

Class III malocclusion is orthodontic anomaly where mandibular arch is in mesial position to maxillary arch. Reasons for Class III malocclusion can be found in mandibular prognathism, maxillar retrognathism or combination of these two. In most cases of mandibular prognathism, it is necessary to postpone the treatment until the growth ceases. However, if certain conditions are accomplished it is possible to start early treatment of class III malocclusion to improve occlusal relations and provide more favorable environment for future growth. The aim of this study was to present treatment of two patients with Class III maloclussion in early mixed dentition, using two different appliances: Delaire mask and Frankel functional regulator type 3. The treatment with Delaire mask resulted in rotation of maxilla downward and forward due to the angle of extraoral part of the mask to the occlusal plane that was modified to be almost 45°. At the end of the treatment facial esthetics was significantly improved. Moving maxilla forward resulted in straight profile, whereas moving maxilla downward lead to coordination of upper, middle and lower facial third. The result of the treatment in patient who used Frankel functional regulator was correction of anterior crossbite by premaxilla development and incisors protrusion. Significant differences in SNA, SNB and ANB angle values at the beginning and at the end of the treatment were not found suggesting that most changes were dental but not skeletal., Skeletna malokluzija III klase je nesklad u međusobnom odnosu gornje i donje vilice, jer je donja vilica postavljena mezijalnije u odnosu na gornju. Uzrok nastanka skeletne malokluzije III klase može biti mandibularni prognatizam, maksilarni retrognatizam ili kombinacija ova dva uzroka. U slučaju isuviše razvijene donje vilice najčešće je potrebno sačekati završetak rasta, kako bi se primenilo konačno lečenje. Međutim, ako su ispunjeni određeni uslovi, moguće je primeniti ranu terapiju III klase, da bi se poboljšali okluzalni odnosi i obezbedila dobra osnova za dalji rast. Cilj ovog rada bio je da se prikaže terapijski efekat dva slučaja malokluzije III klase u ranom uzrastu pomoću različitih ortodontskih aparata: Delerove maske i Frenklovog regulatora funkcije tip 3. Kod pacijentkinje koja je tokom lečenja nosila Delerovu masku gornja vilica je zarotirana unapred i nadole, jer je ugao delovanja sile modifikovan da bude skoro 45 stepeni. Na kraju lečenja postignut je znatno bolji izgled lica. Pomeranjem gornje vilice unapred postignut je prav profil, dok je pomeranje nadole dovelo do usklađivanja visine srednje trećine lica sa gornjom i donjom. Kod pacijenta kod kojeg je tokom lečenja primenjena terapija Frenklovim regulatorom funkcije tip 3 do korekcije obrnutog preklopa sekutića došlo je kombinacijom razvijanja premaksile i protruzije sekutića. Značajne promene u vrednostima uglova SNA, SNB i ANB nisu zabeležene na kraju terapije u odnosu na početak, što bi ukazivalo na to da su postignute promene uglavnom dentalne, a ne skeletne.

Introduction/Objective Class II malocclusions are sagittal malocclusions characterized by a distal relationship of posterior teeth. Depending on the underlying problem, Class II malocclusions can be skeletal or dentoalveolar. Class II malocclusion treatment modality will depend on the cause, severity, and age. Growth modification is the best treatment option in growing patients with skeletal Class II malocclusions. The aim of this study was to establish and compare sagittal and vertical skeletal and dental changes in patients treated with the 'M block' appliance, the Frankel functional regulator, and the Balters' bionator. Methods The sample consisted of 70 patients diagnosed with skeletal Class II malocclusions (ANB > 4°) and mandibular retrognathism (SNB lt 80°). The patients were divided into three groups according to the type of appliance. All the patients went through the standard diagnostic procedure (anamnesis, clinical and functional analysis, study model, panoramic radiograph, and cephalometric analysis), and dental and skeletal age was determined. Treatment effects were analyzed on study models and cephalograms at the end of treatment. Results All the appliances led to significant mandibular anterior movement and sagittal growth, which reduced the ANB values. All three groups of patients presented with neutral growth pattern, upper incisor retrusion, and lower incisor protrusion at the end of treatment. Conclusion The results of this study indicate efficacy of all three appliances in skeletal Class II malocclusion treatment., Uvod/Cilj rada Malokluzije II klase su sagitalne nepravilnosti zagrižaja koje karakteriše distalni odnos bočnih zuba. U zavisnosti od toga koje strukture su u nepravilnom odnosu, dele se na skeletne i dentoalveolarne. Terapija II klase zavisi od uzroka, izraženosti i uzrasta. Najbolji vid terapije ukoliko pacijenti i dalje rastu je modifikacija rasta. Cilj ove studije bio je da se utvrde i uporede sagitalne i vertikalne promene na skeletnim i dentalnim strukturama u toku lečenja M blok-aparatom, Frenklovim regulatorom funkcije tip I i bionatorom po Baltersu tip I. Metode Sedamdeset ispitanika sa dijagnozom skeletnog distalnog zagrižaja (ANB > 4°) i mandibularnog retrognatizma (SNB lt 80°), prema vrsti aparata, podeljeni su u tri grupe. Svi su prošli kroz standardnu dijagnostiku (anamneza, klinička i funkcionalna analiza, analiza studijskih modela, ortopantomografskog i profilnog telerendgenskog snimka). Terapijski efekti i promene analizirani su na studijskim modelima i profilnom snimcima po završetku terapije. Rezultati Sva tri aparata dovela su do značajnog mezijalnog usmeravanja i sagitalnog rasta mandibule, što je smanjilo ANB ugao. U sve tri grupe je utvrđen neutralni rast, kao i retruzija gornjih i protruzija donjih sekutića. Zaključak Rezultati studije ukazuju na efikasnost sva tri ispitivana aparata u lečenju skeletnih malokluzija II klase.

Introduction/Objective Maxillary or mandibular retrognathism are common dentofacial deformities treated by combined orthodontic-surgical treatment. Surgical maxillary or mandibular advancement changes the position and strain of surrounding structures, which may also affect pharyngeal airway dimensions. The aim of this study was to evaluate and compare three-dimensional pharyngeal airway space changes in patients treated with maxillary advancement and those treated with mandibular advancement. Methods The sample consisted of 25 patients - 12 treated with maxillary advancement and 13 with mandibular advancement surgery. Nasopharyngeal (NP) volume, oropharyngeal (OP) volume, and the area of maximum constriction (AMC) in the OP were measured on cone beam computed tomography scans (2 mA / 120 kV / 12'' FOV) taken before and at least three months after surgery. Paired samples t-test was used for analyzing statistical significance of changes (p ≤ 0.05). Results Postoperative OP and NP volumes, as well as the AMC, increased insignificantly in both groups. Conclusion Results suggest that mono-maxillary surgical advancement of the maxilla or the mandible increases pharyngeal airway dimensions., Uvod/Cilj Retrognatizam gornje vilice i retrognatizam donje vilice su česti dentofacijalni deformiteti, koji se leče kombinovanom ortodontsko-hirurškom terapijom. Hirurško pomeranje gornje ili donje vilice unapred menja položaj i napetost okolnih struktura, što takođe utiče na dimenzije faringealnih vazdušnih puteva. Cilj istraživanja bio je da se procene i uporede trodimenzionalne promene faringealnih vazdušnih puteva kod bolesnika lečenih hirurškim pomeranjem gornje ili donje vilice unapred. Metode Uzorak istraživanja se sastojao od 25 bolesnika 12 lečenih hirurškim pomeranjem gornje vilice i 13 lečenih hirurškim pomeranjem donje vilice unapred. Zapremine nazofarinksa i orofarinksa i površine najužeg dela farinksa su merene na CBCT snimcima (2 mA / 120 kV / 12'' FOV) napravljenim pre i bar tri meseca posle hirurške korekcije. Studentov t-test za uparene uzorke je korišćen za analizu statističke značajnosti promena (p ≤ 0,05). Rezultati Zapremine nazofarinksa i orofarinksa i površine najužeg dela farinka povećale su se posle hirurškog pomeranja gornje ili donje vilice unapred. Statistička značajnost nije zabeležena. Zaključak Rezultati ukazuju na to da hirurško pomeranje gornje ili donje vilice unapred dovodi do povećanja dimenzija faringealnih vazdušnih puteva.

Introduction The placement of fixed orthodontic appliances may lead to increased plaque accumulation and changes in subgingival microflora. Objective The aim of this study was to examine the changes in frequency of subgingival microflora that occur after placement and removal of fixed orthodontic appliance using polymerase chain reaction (PCR). Methods This study included 33 orthodontic patients, who were divided into two groups. Subgingival plaque samples were collected from the right upper incisor (U1) and right upper first molar (U6). In group A, the samples were taken three times: before placement appliance (T1), after one month (T2), and after 3 months (T3). In group B the samples were also taken three times: before appliance removal (T1), after one month (T2), and after three months (T3). PCR method was used to determine the presence of P. gingivalis, A. actinomycetemcomitans, T. forsythia, and P. intermedia. Results In group A the frequency of P. gingivalis showed statistically significant decrease at U1 (p=0.049) and U6 (p=0.008), from T1 to T2, and at U1 (p=0.048) from T1 to T3. In group B only the frequency of T. forsythia showed a statistically significant decrease, at U6 (T1 vs. T2, p=0.004; T1 vs. T3, p=0.0003). Regarding other analyzed bacteria, changes in the presence were noticed but no statistical significance was found. Conclusion Placement of fixed appliances may have an impact on subgingival microflora, but in the first months after the placement and removal of the appliance changes were not significant, probably due to good oral hygiene., Uvod Postavka fiksnih ortodontskih aparata može dovesti do povećanog nagomilavanja plaka i promena u subgingivalnoj mikroflori. Cilj rada Cilj ovog rada bio je da se ispitaju promene subgingivalne mikroflore nakon postavke i uklanjanja fiksnih ortodontskih aparata primenom reakcije lančanog umnožavanja molekula DNK (engl. polymerase chain reaction - PCR). Metode rada Studija je obuhvatila 33 pacijenta koja su svrstana u dve grupe (A i B). Uzorci plaka su uzeti iz subgingivalnog prostora desnog gornjeg centralnog sekutića (U1) i desnog gornjeg prvog kutnjaka (U6). U grupi A uzorci su uzimani pre postavke fiksnog aparata (T1), mesec dana posle postavke (T2) i tri meseca od postavke (T3). U grupi B uzorci su uzimani pre uklanjanja aparata (T1), mesec dana posle uklanjanja (T2) i tri meseca nakon uklanjanja (T3). Primenom metode PCR analizirano je postojanje mikroorganizama: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia i Prevotella intermedia. Rezultati U grupi A učestalost P. gingivalis pokazala je statistički značajno smanjenje na oba zuba (U1: p=0,049; U6: p=0,008) u vremenskom intervalu od T1 do T2. Uočeno je i statistički značajno smanjenje zastupljenosti ove bakterije na zubu U1 u intervalu od T1 do T3 (p=0,048). U grupi B samo se učestalost T. forsythia statistički značajno smanjila na zubu U6 u intervalu od T1 do T2 (p=0,004) i od T1 do T3 (p=0,0003). Učestalosti ostalih bakterija u obe grupe ispitanika nisu pokazale statistički značajne promene. Zaključak Postavka fiksnih aparata može da utiče na sastav subgingivalne mikroflore, ali u prvim mesecima nakon postavke i uklanjanja aparata uglavnom nisu uočene statistički značajne promene, verovatno zbog dobre oralne higijene.

Treatment of bone tissue injuries and diseases is still a great challenge for surgeons, but also for researchers who work with materials. Today stem cells are commonly used in bone tissue engineering. However, advances in biocompatible materials design, especially biodegradable porous structure (scaffold) is gaining an important role in the treatment of diseased bone tissue. The basic advantage of these carriers is specifically designed scaffold with defined porosity and pore structure that is favourable for cells settlement. Scaffolds are most commonly used as ceramic brackets because they have excellent characteristics in biodegradation and bioactivity. The process of scaffold production is important because the appropriate technology must ensure control of liquids and reproducibility of scaffold production through standardized process. The aim of this study was to present some of different procedures of scaffold production in bone tissue engineering and point out the advantages and disadvantages of these methods., Terapija i lečenje brojnih povreda i oboljenja koštanog tkiva je još uvek veliki izazov za hirurge, ali i za one istraživače koji se bave materijalima. Na polju inženjerstva koštanog tkiva danas se najčešće koriste matične ćelije. Međutim, napredak u dizajniranju biokompatibilnih materijala, a posebno biodegradibilnih poroznih struktura (skafolda) sve više dobija vrlo značajnu ulogu u lečenju obolelih koštanih tkiva. Specifično dizajnirani skafoldi sa definisanom poroznošću i strukturom pora koja je povoljna za naseljavanje ćelija osnovna je prednost ovih nosača. Skafoldi se najčešće koriste kao keramički nosači jer imaju izvanredne osobine vezane za biodegradaciju i jako izraženu bioaktivnost. Postupak izrade skafolda je vrlo važan jer se odgovarajućom tehnologijom mora obezbediti kontrola tečnosti i reproduktivnost izrade skafolda kroz standardizaciju procesa. Cilj ovog rada je bio da se predstave različiti metodološki postupci izrade skafolda u inženjerstvu koštanog tkiva i ukaže na određene prednosti i nedostatke tih metoda.

Introduction The aim of this study was to evaluate the efficacy of new rotary NiTi instrument XP endo SHAPER (XPS) used with conventional irrigation protocol on the root canal cleaning in the apical area. Material and methods The research was conducted in vitro on 40 extracted single-rooted teeth divided into the four groups. Instrumentation in the first group was performed using iRa Ce NiTi rotary instruments, in the second group the same instruments were used plus XP endo FINISHER (XPF) for smear layer removal. In the third group, canal instrumentation was done using new instrument XPS, and in the fourth XPS instruments plus XPF was used. During the instrumentation 2% NaOCl solution was used for rinsing canals. The SEM analysis of the cleaning quality in the apical third of the canal was performed on longitudinal root cross-sections and standardized microphotography with a 2000x magnification. Results The thickest smear layer in the apical third was recorded in the first group (iRa Ce) NiTi instruments (2.12), and somewhat less in the group with the new XPS instrument (1.95). An identical and somewhat smaller amount of smear layer was registered in the second and fourth groups where XPF was used with the final irrigant (1.64) (p lt 0.001). Conclusion The application of only one instrument (XPS) in the canal enabled efficient cleaning of a very complex apical third. Cleaning was more efficient when XPF was used with final irrigant after the canal instrumentation., Uvod Cilj ovog rada je bio da se SEM analizom proceni efikasnost čišćenja apeksne trećine kanala korena primenom novog rotirajućeg NiTi instrumenta XPS uz protokol konvencionalne irigacije. Materijal i metode rada Istraživanje je realizovano u in vitro uslovima na 40 ekstrahovanih jednokorenih zuba podeljenih u četiri grupe. Instrumentacija kanala u prvoj grupi je izvedena setom iRa Ce NiTi rotirajućih instrumenata, a u drugoj je nakon instrumentacije ovim setom za uklanjanje razmaznog sloja korišćen XPF. U trećoj grupi je instrumentacija kanala realizovana novim instrumentom XPS, a u četvrtoj je posle završene instrumentacije takođe korišćen XPS. Irigacija kanala korena u svim grupama je sprovedena 2% rastvorom NaOCl primenom konvencionalnog protokola. SEM analiza kvaliteta čišćenja apeksne trećine kanala je realizovana na uzdužnim presecima korenova i standardizovanim mikrofotografijama na uveličanju od 2000 puta. Rezultati Dobijeni rezultati su pokazali da je najviše razmaznog sloja u apeksnoj trećini zabeleženo u grupi gde je instrumentacija realizovana setom iRa Ce NiTi instrumenata (2,12), a nešto manje u grupi sa novim instrumentom XPS (1,95). Identična i nešto manja količina razmaznog sloja je registrovana u drugoj i četvrtoj grupi, gde je posle završene instrumentacije korišćen XPF (1,64) (p lt 0,001). Zaključak Primena samo jednog instrumenta (XPS) u instrumentaciji kanala obezbeđuje efikasno čišćenje vrlo kompleksne apeksne trećine. Ovo čišćenje je značajno efikasnije posle primene XPF nakon završene instrumentacije kanala.

This paper analyzes mechanisms of fluorapatite mechanochemical synthesis and its structural characteristics. Several studies of Jokanovic et al. published in appropriate journals and the book 'Nanomedicine, the biggest challenge of the 21st century' are the base for this article. Characteristics of obtained materials show numerous biological advantages associated with the specific structural design of material during the process of synthesis. X-ray diffraction (XRD) and infrared spectroscopy with Fourier transform (FTIR) were used for studying the processes of fluorapatite synthesis., U radu su analizirani mehanizmi mehanohemijske sinteze fluorapatita i njegove strukturne karakteristike. Suštinu istraživanja čine istraživanja V. Jokanovića i saradnika objavljena u odgovarajućim časopisima i knjizi Nanomedicina, najveći izazov 21. veka. Karakteristike dobijenih materijala pokazuju njihove brojne biološke prednosti, koje su povezane sa specifičnostima strukturnog dizajna materijala tokom procesa sinteze. Kao osnove za proučavanje procesa sinteze i mehanizma nastajanja fluorapatita korišćene su metode rendgenske difrakcije (XRD) i infracrvene spektroskopije sa Furijeovom transformacijom (FTIR).

Hipodoncija-urodjeni nedostatak zuba, predstavlja jednu od najĉešćih razvojnih anomalija kod ljudi, i moţe biti nesindromska i sindromska. Do razvoja hipodoncije moţe doći usled izmena u genima ukljuĉenim u morfogenezu zuba, a ĉiji produkti su signalni i transkripcioni faktori, odgovorni za vremenski programiranu ekspresiju gena u fazama pupoljka, kape i zvona. Iz palete gena ukljuĉenih u odontogenezu, zbog svog kljuĉnog znaĉaja izdvaja se WNT10A gen (eksprimiran u dentalnom epitelu), i RUNX2 gen (eksprimiran u mezenhimu). Mutacije gena povezanih sa odontogenezom mogu dovesti do izmena u morfologiji, broju i strukturi zuba. Ciljevi ove studije su bili da se ispita zastupljenost potencijalnih mutacija u RUNX2 i WNT10A genima i utvrdi njihov naĉin nasledjivanja kod izolovanih (nesindromskih) formi hipodoncije. Drugi deo istraţivanja odnosio se na uporedjivanje veliĉine zuba pacijenata sa urodjenim nedostatkom zuba i zdravih pacijenata kako bi se utvrdilo da li je hipodoncija/oligodoncija povezana sa eventualnim anomalijama veliĉine zuba . Mutacioni status RUNX2 i WNT10A gena, odreĊen je kod 24 porodice (72 ispitanika), pri ĉemu je kod 29 osoba, kliniĉki potvrdjena hipodoncija. Merenje meziodistalnih širina zuba je uradjeno kod 25 pacijenata sa uroĊenim nedostatkom zuba i 25 pacijenata kontrolne grupe. Prisustvo mutacija potvrĊeno je primenom tehnike direktnog sekvenciranja, dok je odreĊivanje meziodistalnih širina zuba uraĊeno primenom 3D skenera i merenjima na digitalnim modelima u kompjuterskom programu. Mutaciona analiza WNT10A gena, pokazala je prisustvo 2 nukleotidne izmene u regionu egzona 2 (rs10180544, rs141074983) i 3 izmene u egzonu 3 (rs121908120, rs77583146, rs146902156). Mutacionom analizom RUNX2 gena utvrĊeno je prisustvo 4 nukleotidne izmene u egzonu 3 (rs6921145, COSM1658842, rs759395776, rs768156797) i jedna nukleotidna izmena u regionu egzona 4 (34 insC)..., Hypodontia (tooth agenesis) is one of the most common dental anomalies in humans that occurs either in non-syndromic forms or as a part of various syndroms. Hypodontia can be a result of nucleotide substitutions in genes that are involved in tooth morphogenesis, whose products are signal molecules and transcription factors that control gene expression in different phases of tooth morphogenesis (bud, cap and bell stage). Among many genes, WNT10A (with its expression in dental epithelial tissue) and RUNX2 gene (with its expression in mesenchimal tissue) have been singled out due to their key role in odontogenesis. Mutations of genes involved in odontogenesis can lead to changes in tooth morphology, structure and the number of teeth. The aim of this study was to examine the presence of potential mutations in RUNX2 and WNT10A genes, and to determine their inheritance path in patients with isolated (non-syndromic) forms of tooth agenesis. The second part of the investigation was aimed to compare tooth dimensions in hypodontia patients and healthy controls, in order to determine whether hypodontia / olygodontia is related to potential tooth size anomalies. Mutational status for RUNX2 and WNT10A genes was determined for 24 families. The sample included 72 subjects, 29 of which had clinically confirmed tooth agenesis. Mesiodistal tooth width was measured in 25 hypodontia patients and 25 healthy controls. Genetic mutations presence was confirmed by direct sequencing. Mesiodistal tooth width was measured on digitized study models using a computer software. Mutational analysis of WNT10A gene revealed the presence of two nucleotide substitutions in the exon 2 region (rs10180544, rs141074983) and three nucleotide substitutions in exon 3 (rs121908120, rs77583146, rs146902156). Mutational analysis of RUNX2 gene revealed four nucleotide substitutions in exon 3 (rs6921145, COSM1658842, rs759395776, rs768156797) and one in exon 4 (34 insC). Mutations in WNT10A gene were present in 52

Introduction The study included application of liners and dental composites in to cavities of six experimental animals - rabbits (Oryctolagus cuniculus). Objective The aim of the study was to investigate rabbit dental pulp response to different liners. Methods Cavity preparation for class V were made on the maxillary central incisors and one lower incisor, while the second lower incisor served as a control tooth. These teeth were restored with the use of one of the following liners - Calcimol LC, ANA Liner and Fuji II LC Improved, and Ceram-X mono dental composite. After an observation period of five days animals were sacrificed and prepared for histological analysis. The existence and degree of the pulp inflammation was determined by using a light microscope. Results Results showed that the used liners do not cause distortion of the structure and continuity of the odontoblastic layer. Inflammation was not registered in the control group, while in each group of tested materials one tooth with mild signs of hyperemia was registered. Results showed that all three tested liners demonstrated favorable effects on the pulp of the tooth and did not lead to inflammatory reactions. Conclusion Histological analysis of the dental pulp of experimental animals suggests that the liners used in this study do not compromise the integrity of the odontoblastic layer, if it is applied over a thin layer of dentin. In each group of tested materials one tooth with mild signs of hyperemia and vasodilation was registered., Uvod Ispitivanje je obuhvatilo primenu lajnera i kompozitnog materijala u kavitete intaktnih zuba šest eksperimentalnih životinja - kunića. Cilj rada Cilj istraživanja je bio da se proveri uticaj različitih lajnera na nastanak i stepen zapaljenja pulpe nakon primene u kavitete zuba kunića. Metode rada Kod svake životinje su urađene preparacije V klase na dva gornja centralna sekutića i na jednom donjem sekutiću, dok je drugi donji sekutić služio kao kontrolni zub. U preparisane kavitete su aplikovani materijali koji su indikovani za primenu kod dubokih kaviteta neposredno pre postavljanja kompozitnih restauracija na zubima: Calcimol LC, ANA Liner i Fuji II LC improved. Svi kaviteti su restaurisani kompozitnim materialom CeramX-mono. Posle opservacionog perioda od pet dana životinje su žrtvovane i pripremljene za histopatološku analizu. Rezultati Svetlosnom mikroskopijom analizirani su postojanje i stepen zapaljenja u zubnoj pulpi. Rezultati su pokazali da korišćeni lajneri ne narušavaju strukturu i kontinuitet odontoblastnog sloja. Na zubima kontrolne grupe nije uočeno zapaljenje, dok je kod testiranih materijala u svakoj grupi zabeležen jedan zub sa blagim znacima hiperemije. Dobijeni rezultati su pokazali da su sva tri ispitana lajnera povoljno uticala na pulpu zuba i nakon aplikacije nisu doveli do zapaljenjskih reakcija u pulpi. Zaključak Histološka analiza zubne pulpe eksperimentalnih životinja je pokazala da lajneri korišćeni u ovom istraživanju ne narušavaju integritet odontoblasta eksperimentalnih životinja ukoliko se nanose preko tankog sloja dentina. Utvrđeno je samo postojanje blage hiperemije i vazodilatacije u po jednom uzorku pulpe zuba zaštićenih testiranim lajnerima.

Introduction The aim of this study was to evaluate using SEM analysis the effectiveness of a new instrument XP-endo Finisher in cleaning root canal walls after instrumentation with BioRaCe NiTi rotary instruments. Material and Methods This in vitro study was conducted on 30 extracted single rooted teeth divided in two groups. Instrumentation of all canals was done using basic BioRaCe NiTi rotary instruments with copious irrigation of 2% NaOCl. In the first group, after complete instrumentation smear layer was removed using XP-endo Finisher, while the other group served as negative control. The roots were then after longitudinally cut and SEM analysis was performed. The presence of smear layer in the coronal, middle and apical third was assessed. The data were statistically analyzed using Mann-Whitney U-test (p lt 0.05). Results The results showed that average value of smear layer on the canal walls in the XP-endo Finisher group was significantly lower than in the control group (p lt 0.05). Conclusion XP-endo Finisher after canal instrumentation with NiTi rotary instruments effectively cleaned canal walls and removed smear layer., Uvod Cilj ovog rada je bio da se SEM analizom proveri efikasnost novog instrumenta XP-endo Finisher na kvalitet čišćenja zidova kanala korena zuba nakon instrumentacije BioRaCe NiTi rotirajućim instrumentima. Materijal i metode rada Istraživanja su izvedena u uslovima in vitro na 30 ekstrahovanih jednokorenih zuba podeljenih u dve grupe. Instrumentacija svih kanala je realizovana osnovnim setom BioRaCe NiTi rotirajućih instrumenata uz irigaciju dvoprocentnim rastvorom NaOCl. U prvoj grupi je nakon instrumentacije za uklanjanje razmaznog sloja korišćen XP-endo Finisher, a druga grupa je služila kao kontrolna. Korenovi svih zuba su uzdužno podeljeni i SEM metodom je analiziran kvalitet čišćenja kanala korena, odnosno postojanje razmaznog sloja u kruničnoj, srednjoj i apeksnoj trećini. Podaci su statistički analizirani Man-Vitnijevim (Mann-Whitney) U-testom (p lt 0,05). Rezultati Dobijeni rezultati su pokazali da je ukupna srednja vrednost postojanja razmaznog sloja na zidovima kanala u grupi gde je korišćen XP-endo Finisher bila statistički značajno manja nego u kontrolnoj grupi uzoraka (p lt 0,05). Zaključak XP-endo Finisher posle obrade kanala NiTi rotirajućim instrumentima efikasno čisti kanal i uklanja razmazni sloj sa zidova kanala.

Introduction Calcium silicate cements are most commonly used materials in endodontics for many indications due to their exceptional biological and physical properties. The aim of this study was to assess solubility and porosity of new experimental nanostructured calcium silicate cement. Material and Methods A novel nanostructured calcium silicate cement (CS), commercialized calcium silicate cement (Biodentin), traditional glass ionomer cement (GIC) (Micron Superior) and resin-reinforced glass ionomer cement (Fuji VIII) were used in this study. All materials were prepared as per manufactuers' instructions, placed in metal rings of 16x2 mm diameter and kept in an incubator at 37°C for 24 hours. After that they were weighed and put in plastic containers filled with 25 ml of water for additional 24 hours. Then after all samples were weighed again and resorption and solubility were calculated. Results The highest solubility was found for new CS cement (12.45) followed by conventional GIC Micron Superior (11.5) and Biodentin (6.1) whereas the lowest solubility was for resin reinforced GIC Fuji VIII (3.8). These differences were statistically significant (p lt 0.005). The highest absorption was also observed in new CS cement (24.15), followed by Biodentin (18.5) and Micron superior (17.95) while the lowest was for GIC Fuji VIII (7.75). These differences were also statistically significant except between Micron Superior and Biodentin. Conclusion Solubility and porosity of new nanostructured calcium silicate cement were significantly higher than for traditional calcium silicate cement, traditional GIC and resin-reinforced GIC., Uvod Cementi na bazi kalcijum-silikata danas su najčešće korišćeni materijali u brojnim endodontskim indikacijama zahvaljujući, pre svega, njihovim izuzetnim biološkim i odgovarajućim fizičkim svojstvima. Cilj ovog radaje bio da se proveri rastvorljivost i poroznost eksperimentalnog nanostrukturnog kalcijumsilikatnog cementa. Materijal i metode rada Kao materijal u istraživanju korišćeni su novosintetisani nanostrukturni kalcijumsilikatni (CS) cement, komercijalni kalcijumsilikatni cement (Biodentin), konvencionalni glasjonomer-cement (GJC) Micron Superior i glasjonomer-cement ojačan smolom Fuji VIII. Svi materijali su nakon pripreme postavljeni u metalne prstenove promera 16x2 mm i čuvani u inkubatoru na 37°C tokom 24 sata, a zatim izmereni. Materijali su potom stavljeni u plastične kontejnere sa 25 ml vode i posle 24 časa posušeni, ponovo izmereni, a potom su utvrđivane apsorpcija i rastvorljivost. Rezultati Dobijeni rezultati su ukazali na najveću rastvorljivost kod novosintetisanog CS cementa (12,45), potom kod konvencionalnog GJC Micron Superior (11,5), nešto manju kod Biodentina (6,1) a najmanju kod GJC ojačanog smolom Fuji VIII (3,8). Ove razlike su bile statistički značajne (p lt 0,005). Najveća apsorpcija je takođe uočena kod CS cementa (24,15), zatim kod Biodentina (18,5) i GJC Micron Superior (17,95), a najmanja kod GJC Fuji VIII (7,75). I ove razlike su bile statistički značajne, osim između GJC Micron Superior i Biodentina. Zaključak Rastvorljivost i poroznost novosintetisanog nanostrukturnog kalcijumsilikatnog cementa je bila značajno veca u poređenju s komercijalnim cementom na bazi kalcijum-silikata, konvencionalnim GJC i GJC ojačanim smolom.

Calcium phosphates, together with polymers, are most commonly used materials in bone engineering since their composition is similar to bone. They are used to fulfill various defects caused by injury or bone disease, as well as for the preparation of endodontic mixtures. Because of their great importance in dentistry, these materials are given special attention in the current paper. This paper is a part of the monograph entitled 'Nanomedicine, the Greatest Challenge of the 21st Century', which attracted great interest of technical and professional communities in different areas of medicine. Also for the last two years this book is promoted by the Student Cultural Centre as the only national book chosen in the narrowest election. That fact is very important for young researchers who study tissue engineering, endodontics and implantology., Kalcijum- fosfati, zajedno s nekim polimerima, najviše su korišćeni materijali u inženjerstvu koštanog tkiva, budući da su po sastavu bliski prirodnoj kosti. Koriste se za ispune različitih oštećenja nastalih usled povreda ili bolesti koštanog tkiva, kao i za pripremu endodontskih mešavina za primenu u stomatologiji. Zbog izuzetnog značaja u stomatologiji, kalcijumfosfatni materijali zaslužuju posebno mesto, pa će im u okviru ovog rada, ali i radova koji će uslediti, biti posvećena posebna pažnja. Radovi su najvećim delom sastavni deo monografije pod nazivom 'Nanomedicina, najveći izazov 21. veka', koja je pobudila veliko interesovanje stručne i profesionalne javnosti usmerene ka različitim oblastima medicine i koju je već dve godine zaredom Studentski kulturni centar, kao jedinu knjigu domaćeg autora, promovisao kao knjigu najužeg izbora. Verujemo da je ta činjenica posebno važna za mlađe istraživače koji se bave problemima inženjerstva tkiva, endodoncijom i implantologijom.