Computer-aided technologies in diagnostics and therapy of impacted teeth

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DENTAL PATIENTS ON ORAL ANTICOAGULANT THERAPY

Oral anticoagulant therapy (OAT) has been used for more than half a century in themanagement and prevention of thromoembolic disorders. Due to somewhat awkwardphenomena accompanying anticoagulant therapy during dental-surgical interventions,dentists have to be well acquainted with the characteristics of the therapy and themeasures to be undertaken in the management of patients on OAT. This paper aims topresent a short overview of the procedures and measures to be undertaken by a dentistin the management of patients on OAT

Analiza varijacija sagitalnog položaja viličnih kostiju u malokluziji skeletne klase III

Background/Aim. Skeletal Class III malocclusion is a discrepancy in the sagittal jaw relationship, due to imbalances in their development and/or position, resulting in the dominant appearance of the lower jaw in facial profile. The aim of this study was to determine variations in the sagittal position of the jaw bones to the cranial base in subjects with skeletal Class III, for the earliest possible diagnosis of malocclusion. Methods. Fifty children and as many adults with skeletal Class III, both sexes, were examined and selected, based on the findings of sagittal interjaw relationship (ANB) ≤ 0° from the cephalometric analysis of tele-x-ray profile head shots. The subjects were grouped according to age. The first group consisted of children aged 6-12 years, and another group, of adults aged 18-26 years. We measured the angles of maxillary prognathism (SNA), mandibular prognathism (SNB) and ANB. Based on these results, within the respective groups subclassification into the subgroups was done, among which a significant difference measured values was evaluated. In both groups a significant correlation of the determined values was evaluated. Results. An average SNA angle ranged 77.36 ± 3.58 in children and 77.32 ± 4.88 in adults, while an average SNB angle was 79.46 ± 3.91 in the group of children and 81.12 ± 3.76 in adults. An average ANB angle was -2.10 ± 2.07 in children, and -4.00 ± 2.34 in adults. In both groups, a significant correlation between the measured values and a significant difference in the values of all the measured parameters were found between patients from different subgroups (p lt 0.01). Conclusion. The most common morphological variation of sagittal position of the upper jaw is its retrognatism, which is equally present in both children and adults. Sagittal position of the lower jaw in most of the adults was prognathic, while mandible prognathism in the children was less present.Uvod/Cilj. Malokluzija skeletne klase III je nesklad u sagitalnom odnosu vilica, nastao usled neusklađenosti njihove razvijenosti i/ili položaja, što rezultira dominantnim izgledom donje vilice u facijalnom profilu. Cilj ove studije bio je da se utvrde varijacije sagitalnog položaja viličnih kostiju prema kranijalnoj bazi kod ispitanika sa skeletnom klasom III, radi što ranijeg dijagnostikovanja ove malokluzije. Metode. Pedesotoro dece i isto toliko odraslih sa skeletnom klasom III, oba pola, pregledano je i selekcionisano na osnovu nalaza ugla sagitalnog međuviličnog odnosa (ANB) ≤ 0° iz kefalometrijske analize profilnih telerendgenskih snimaka glave. Ispitanici su bili grupisani prema uzrastu. Prvu grupu, činila su deca starosti 6-12 godina, a drugu grupu odrasli starosti 18-26 godina. Mereni su uglovi prognatizma gornje vilice (SNA), prognatizma donje vilice (SNB) i ANB. Na osnovu dobijenih rezultata, unutar pripadajuće grupe učinjena je supklasifikacija na podgrupe, između kojih je procenjivana značajnost razlike izmerenih vrednosti. U obe grupe određivana je značajnost korelacije utvrđenih vrednosti. Rezultati. Prosečne vrednosti ugla SNA iznosile su kod dece 77,36 ± 3,58° i 77,32 ± 4,88° kod odraslih, a ugla SNB 79,46 ± 3,91° u grupi dece i 81,12 ± 3,76° kod odraslih. Ugao ANB prosečno je iznosio kod dece -2,10 ± 2,07°, a kod odraslih -4,00 ± 2,34°. U obe grupe utvr đena je značajna korelacija izmerenih vrednosti i značajna razlika u vrednostima svih merenih parametara između ispitanika iz različitih podgrupa (p lt 0,01). Zaključak. Najčešća morfološka varijacija sagitalnog položaja gornje vilice je njen retrognatizam, koji je u jednakoj meri zastupljen kod dece i kod odraslih. Sagitalni položaj donje vilice kod najvećeg broja odraslih bio je prognat, dok je kod dece prognatizam donje vilice bio prisutan u manjoj meri

Efekat lokalne primene plazme bogate trombocitima i vođene regeneracije tkiva na zarastanje kosti kod rane ugradnje dentalnih implantata – histomorfometrijska analiza

Introduction. In order to provide the most favorable conditions for bone healing following implant loading, new techniques such as the use of growth factors to directly or indirectly regulate cell and tissue growth are becoming increasingly popular. Simplicity in producing concentrated thrombocytes derived from platelet-rich plasma has led to increasing application of growth factors derived from thrombocytes, such as PDGF, TGF-β, IGF and VEGF, in order to increase the percentage of bone-to-implant contact that provides better implant stability and possibly earlier functional loading. The aim of the study was to determine the effects of platelet-rich plasma and guided tissue regeneration on bone regeneration in the case of bone defects in early dental implant insertion. Materials and Methods. This experimental study was conducted on 10 study dogs that received 40 BCT implants, i.e., 4 implants per dog. The study included early dental implant placement in the sites of the extracted premolars. Artificial bone defects, resembling peri-implantitis defects, were made on the mesial side of each site, and the defects were filled using suitable guided tissue regeneration protocols with platelet-rich plasma derived from each experimental animal an hour before surgery. Histopathologic and histomorphometric evaluations were performed 10 months following the implantation. Results and Conclusion. The applied protocols had different effects on bone healing. According to the results obtained, the use of platelet-rich plasma combined with deproteinized bovine bone and bovine-derived resorptive membrane provided superior bone defect ossification.Uvod. Potreba da se stvore što bolji uslovi za koštano zarastanje nakon ugradnje implantata poslednjih par godina uticala je na primenu faktora rasta koji direktno ili indirektno regulišu rast ćelija i tkiva. Jednostavnost dobijanja koncentrovanih trombocita izdvojenih iz plazme bogate trombocitima, dovela je do sve šire primene faktora rasta poreklom iz trombocita poput PDGF, TGF-β, IGF, VEGF i mnogih drugih, sa ciljem postizanja što većeg procenta kontakta površine implantata sa kosti, što obezbeđuje povećanu stabilnost implantata i brže funkcionalno opterećenje. Cilj rada bio je da se ispita uticaj plazme bogate trombocitima i vođene tkivne regeneracije tkiva u koštanim defektima kod rane ugradnje dentalnih impantata na koštanu regeneraciju. Materijal i metode. Eksperimentalna studija sprovedena je na 10 eksperimentalnih pasa kod kojih je ugrađeno 40 BCT implantata i to po četri svakom. Eksperiment se sastojao od rane ugradnje umplantate na mestima izvađenih premolara. Veštački koštani defekti, nalik periimplantatnim defektima, napravljeni su na mezijalnoj strani svake preparacije. Ti defekti su popunjeni prateći odgovarajuće postupke vodjene tkivne regeneracije, uz korišćenje plazme bogate trombocitima, dobijene iz krvi eksperimentalnih životinja sat vremena pre intervencije. Histopatološke i histomorfometrijske analize rađene su 10 meseci nakon ugradnje implantata. Rezultati i zaključak. Primenjeni protokoli različito utiču na ispunjenost koštanih defekata i koštano zarastanje. Na osnovu dobijenih rezultata došli smo do zaključka da je osifikacija koštanih defekata najveća u protokolu prema kome se primenjuje plazma bogata trombocitima u kombinaciji sa bovinom deproteinizovanom kosti i resorptivnom membranom bovinog porekla

Effect of local administration of platelet-rich plasma and guided tissue regeneration on the level of bone resorption in early dental implant insertion

Background/Aim. Osseointegration is a result of cellular migration, differentiation, bone formation, and bone remodeling on the surface of an implant. Each of these processes depends on platelets and blood coagulum. Platelet-rich plasma (PRP) is used to improve osseointegration and stability of implants. The aim of the research was to test the influence that PRP and guided tissue regeneration in bone defects have on bone defect filling and the level of bone resorption in early implant insertion. Methods. This experimental study included 10 dogs. A total of 40 BCT implants were inserted, 4 in each dog (two on the left side and two on the right side), with guided tissue regeneration. Radiologic analyses were done immediately after the insertion and 10 weeks after the insertion. Bone defect filling was measured by a graduated probe 10 weeks after the implant insertion. The following protocols were tested: I - PRP in combination with bovine deproteinized bone (BDB) and resorptive membrane of bovine origin (RBDM), II - BDB + RBDM, III - PRP + RBDM and IV - RBDM. Results. The applied protocols affected differently the bone defect filling and the level of bone resorption. Significantly better results (the lowest bone resorption) were achieved with protocol I (PRP + BDB + RBDM) in comparison with protocols III (PRP + RBDM) and IV (RBDM), but not with protocol II (BDB + RBDM). On the other hand, no significant difference was found among protocols II (BDB + RBDM), III (PRP + RBDM) and IV (RBDM) in the level of bone tissue resorption. Conslusion. The bone defect filling was largest and the level of bone resorption was lowest in the protocol with PRP applied in combination with BDB and RBDM

Production of Soluble Receptor Activator of Nuclear Factor Kappa-Β Ligand and Osteoprotegerin by Apical Periodontitis Cells in Culture and Their Modulation by Cytokines

RANKL, a bone-destructive cytokine, and OPG, its osteoprotective counterpart, are expressed in periapical lesions (PLs), which represent hystopatological manifestations of apical periodontitis. However, their regulation in PLs has not been elucidated yet. Therefore, our aim was to study the production of RANKL and OPG and their modulation by pro- and anti-inflammatory cytokines in PL cell cultures. Isolated PL cells were cultured alone or with addition of TNF-α, IFN-ϒ, IL-17, IL-4, IL-10, and IL- 33, respectively. The levels of RANKL and OPG in supernatants were measured by ELISA. The proportion of CD3+ (T cells) and CD19+/CD138+ (B cells/plasma cells) within isolated PLs was determined by immunocytochemistry. The levels of RANKL were higher in cultures of symptomatic PLs compared to asymptomatic PLs and PLs with the dominance of T cells (T-type lesions) over B cells/plasma cells (B-type lesions). A higher proportion of osteodestructive processes (RANKL/OPG ratio>1.0) were detected in symptomatic PLs. The production of RANKL was upregulated by IFN-ϒ and IL-17 and higher concentrations of IL-33. IL-10 and lower concentrations of IL-33 augmented the production of OPG. The addition of either RANKL or anti-RANKL antibody to the cultures did not modify significantly the production of OPG. In conclusion, this original PL cell culture model suggests that increased bone destruction through upregulated production of RANKL could be associated with exacerbation of inflammation in PLs with the predominance of Th1 and Th17 responses and increased secretion of IL-33. In contrast, IL-10 and lower levels of IL-33, through upregulation of OPG, may suppress osteolytic processes

Mesenchymal stem cells from periapical lesions modulate cytokine production by local immune cells

Background/Aim. Mesenchymal stem cells (MSCs) have been shown to suppress immune and inflammatory reactions. However, it is not known whether MSCs from inflammatory tissues, such as periapical lesions (PLs) have similar effects. This question was addressed in this study in which the aim was to examine the capacity of PL-MSCs for modulating cytokine production by local immune cells. Methods. PL-MSCs were isolated from asymptomatic (as) and symptomatic (sy) PLs. Their phenotype was analyzed by flow cytometry by detecting MSC surface markers. Anti-inflammatory and immunomodulatory properties of PL-MSCs were examined by measuring cytokine production in direct co-culture experiments with mononuclear cells (MNCs) isolated from asPLs and syPLs, respectively. The levels of cytokines in supernatants were determined by specific ELISA kits. Results. Both PL-MSCs lines were characterized by typical MSC phenotype, with the predominance of CD29, CD44, CD90, CD105 and CD166. However, the lines, independently of their similar phenotype had the same modulatory effect on cytokine production, but the response of asPL-MNCs and syPL-MNCs was different, in spite of similar composition of these MNCs. Both MSC lines inhibited the production of inflammatory cytokines, such as interleukin-1_ (IL-1_) and tumor necrosis factor-_ (TNF-_). However, IL-8 was only down-regulated in the co-culture of these MSC lines with syPL-MNCs. The PL-MSCs also modulated the production of immunoregulatory cytokines. Transforming growth factor-_ (TGF-_) was up-regulated by both as- and syPL-MNCs but IL-10 was up-regulated only by asPL-MNCs. Conclusion. Our results showed that PL-MSCs contribute to the restriction of local inflammatory and immune responses, but this effect is probably less efficient during the exacerbation of PL inflammation. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 175102