Radiographic and Prosthetic Assessment Prior to Implantoprosthetic Therapy

Jedan od osnovnih uvjeta uspješnosti terapije oseointegrirajućim usadcima jest dobro predkirurško planiranje. Svrha je ovoga rada prikazati na slučaju djelomične bezubosti u distalnom dijelu mandibule mogućnosti radiološke i protetske ocjene prije kirurškoga tretmana. Na modelu čeljusti učinjeno je dijagnostičko navoštavanje. Nakon toga izrađena je šablona iz vakuum termoplastične folije. Metalne kuglice poznatoga promjera stavljene su u pozicije navoštanih zuba kako bi se radiološkom tehnikom ocijenila mogućnost implantacije u predviđenim pozicijama. Učinjen je klasični ortopantomogram te na temelju njega i slojeviti tomogram s točnim presjecima mandibule na položajima budućih usadaka. Na temelju rendgenskih nalaza određen je položaj i duljina usadaka. Prikazan je klasičan dvofazni kirurški protokol te operacijska tehnika s intraoralnim pretprotetskim šablonama. Uporabljeni su usadci Astratech microthread koničnoga profila kako bi se promjerom usatka što više približili promjeru budućega zuba. Dužina usatka određena je u skladu s navedenom radiološkom raščlambom tako da je usadak na poziciji 35 kraći od usadaka 34 i 37 zbog anatomske pozicije foramena mentale. Pri kirurškome pozicioniranju usatka osim pozicije koja je određena šablonom usadci su u okomitome smjeru pozicionirani u skladu s biološkom širinom sluznice i u konačnici parodontološko estetskim zahtjevima. Rezultati prikazuju uspješnost terapije nakon dobra planiranja i pripreme. Prikazana je prednost slojevite tomografije u planiranju i određivanju anatomsko-morfoloških karakteristika donje čeljusti koja nam daje sigurnost u izboru dužine, a osobito širine usatka. Predkirurško planiranje je postupak kojime možemo predvidjeti položaj usatka i estetiku budućega protetskog rada te tako olakšati kirurški zahvat.One of the fundamental pre-conditions for successful therapy by osseo-integrating implants is good pre-surgical planning. The aim of this work is to present the possibilities of radiographic and prosthetic evaluation prior to surgical treatment in the case of partial edentulousness.in the distal part of the mandibula. Diagnostic wax-up is done on a model of the jaw. After which a pattern is made of vacuum thermoplastic foil. Metal pellets of known diameter are placed in the positions of the waxed-up teeth to enable radiographic evaluation of the possibility of implantation in the planned positions. Classical orthopantomography is performed on the basis of which a multi-layer tomogram is done with exact cross-sections of the mandibula in the positions of future implants. On the basis of radiographic findings the position and length of the implants are determined. The classical two-phase surgical protocol is described and surgical technique with intraoral pre-prosthetic patterns. Astratech microthread implants of conical profile are used to ensure that the implant diameter is as close as possible to the diameter of the future tooth. The length of an implant is determined in accordance with the cited radiographic analysis, so that the implant in position 35 is shorter in relation to implants 34 and 37, due to the anatomic position of the foramen mentale. During surgical positioning of implants, apart from the position which is defined by the pattern, in the vertical direction the implants are positioned in accordance with the biological width of the mucous membrane and finally with periodontal aesthetic requirements. The results show the success of the therapy following good planning and preparation. The advantage is shown of multi-layer tomography in planning and determining the anatomical-morphological characteristics of the lower jaw, which provides assurance in the choice of length and particularly the width of the implant. Pre-surgical planning is a procedure by which it is possible to foresee the position of an implant and aesthetics of future prosthetic work, and thus to facilitate the surgical intervention

Therapy of Advanced Periimplantitis - Case Presentation Clinical and Microbial Results after 10 Months

Sve više bude postavljenih usadaka neizbježno je da će biti više komplikacija u vezi s takvim terapijskim postupkom. Jedna od komplikacija koju je najteže izliječiti i koja posljedično može dovesti do gubitka usatka jest bakterijski uzrokovan periimplantitis. U ovome prikazu slučaja opisat će se uspješna terapija uznapredovala periimplantitisa. Pacijent u dobi od 58 godina poslan je parodontologu zbog smetnji u usnoj šupljini u obliku neugodna zadaha te gnojenja oko zuba i usadaka. Prigodom parodontološkoga pregleda opaženo je da su oba usatka na mjestima 22 i 25 zahvaćena periimplantatnim mukozitisom te da postoji krvarenje i gnojenje pri sondiranju. Kod usatka u području 25 postojao je i problem potpunoga nedostatka keratinizirane gingive. Na temelju kliničkog i rtg nalaza te pozitivnog mikrobiološog nalaza na parodontopatogene dijagnosticiran je periimplatitis oko oba usatka. Inicijalna parodontološka terapija završena je u četiri posjeta. Pacijent je dobio upute kako da održava oralnu higijenu te je uključena antiseptička terapija, ispiranje klorheksidinom i uporaba klorheksidinskoga gela izravno u džepove oko usadaka. Kako i nakon takve terapije gnojenje nije prestalo, uključena je i antibiotska terapija te ispiranje džepova jodom. Nakon što je infektivni proces uspješno stavljen pod nadzor, u daljnjem terapijskom postupku proveden je parodontološki kirurški zahvat kako bi se oko usatka 25 pokušao ispraviti nedostatak keratinizirane gingive i dobiti nov pričvrstak. Pošto je režanj odignut, površina usatka očišćena je sterilnom vatom natopljenom u klorheksidin, a s nepca je uzet vezivni presadak te je postavljen na kosti i na izložene navoje usatka. Preko presatka postavljen je Gengigel (hijaluronska kiselina) radi boljeg cijeljenja rane. Pet mjeseci nakon operacije ponovljena je mikrobiološka raščlamba te više nije bilo parodontnih patogena, a klinička mjerenja su pokazala da je smanjena dubina sondiranja, da ne postoji krvarenje ili gnojenje i da je nastala zona keratinizirane gingive od 2 mm oko usatka 25.With the ever increasing number of placed implants it is inevitable that the number of complications connected with such therapeutic procedure will also increase. One of the complications which is hardest to treat and which consequently can lead to loss of the implant, is bacterial caused periimplantitis. This case presentation describes the successful therapy of advanced periimplantitis. The male patient, aged 58 years, was referred to the periodontist because of problems in the oral cavity in the form of unpleasant breath and suppuration around the tooth and implant. During the periodontal examination it was observed that both implants on places 22 and 25 were affected by periimplantic mucositis and bleeding and suppuration occurred during probing. With regard to the implant in area 25 the problem of complete loss of keratinised gingiva was also present. On the basis of the clinical and X-ray findings, and positive microbial test for periodontopathogens, periimplantitis was diagnosed around both implants. Initial periodontological therapy was carried out in four visits. The patient received instructions on the maintenance of oral hygiene and antiseptic therapy was included, rinsing with chlorhexidine and application of chlorhexidine gel directly into the pockets around the implants. As after this therapy the suppuration did not stop antibiotic therapy was included, with rinsing of the pockets with iodine. After successful control of the infective process, further therapy involved a periodontological surgical operation in order to correct the loss of keratinised gingiva around implant 25 and to obtain new attachment. After lifting the flap the surface of the implant was cleaned with sterile cotton wool soaked in chlorhexidine, and from the palate a connective transplant was taken and placed on the bone and the exposed thread of the implant. Gengigel (hyaluronic acid) was placed over the transplant for better healing of the wound. Five months after the operation microbial analysis was repeated. Periodontal pathogens were no longer present and clinical measurements showed reduced probing depth, absence of bleeding and suppuration, and the occurrence of zones of keratinised gingiva of 2 mm around implant 25

New experimental model of acute aqueductal blockage in cats: effects on cerebrospinal fluid pressure and the size of brain ventricles

It is generally assumed that cerebrospinal fluid (CSF) is secreted in the brain ventricles, and so after an acute blockage of the aqueduct of Sylvius an increase in the ventricular CSF pressure and dilation of isolated ventricles may be expected. We have tested this hypothesis in cats. After blocking the aqueduct, we measured the CSF pressure in both isolated ventricles and the cisterna magna, and performed radiographic monitoring of the cross-sectional area of the lateral ventricle. The complete aqueductal blockage was achieved by implanting a plastic cannula into the aqueduct of Sylvius through a small tunnel in the vermis of the cerebellum in the chloralose-anesthetized cats. After the reconstitution of the occipital bone, the CSF pressure was measured in the isolated ventricles via a plastic cannula implanted in the aqueduct of Sylvius and in the cisterna magna via a stainless steel cannula. During the following 2 h, the CSF pressures in the isolated ventricles and cisterna magna were identical to those in control conditions. We also monitored the ventricular cross-sectional area by means of radiography for 2 h after the aqueductal blockage and failed to observe any significant changes. When mock CSF was infused into isolated ventricles to imitate the CSF secretion, the gradient of pressure between the ventricle and cisterna magna developed, and disappeared as soon as the infusion was terminated. However, when mock CSF was infused into the cisterna magna at various rates, the resulting increased subarachnoid CSF pressure was accurately transmitted across the brain parenchyma into the CSF of isolated ventricles. The lack of the increase in the CSF pressure and ventricular dilation during 2 h of aqueductal blockage suggests that aqueductal obstruction by itself does not lead to development of hypertensive acute hydrocephalus in cats

Deep learning based approach for optic disc and optic cup semantic segmentation for glaucoma analysis in retinal fundus images

Optic disc and optic cup are one of the most recognized retinal landmarks, and there are numerous methods for their automatic detection. Segmented optic disc and optic cup are useful in providing the contextual information about the retinal image that can aid in the detection of other retinal features, but it is also useful in the automatic detection and monitoring of glaucoma. This paper proposes a deep learning based approach for the automatic optic disc and optic cup semantic segmentation, but also the new model for possible glaucoma detection. The proposed method was trained on DRIVE and DIARETDB1 image datasets and evaluated on MESSIDOR dataset, where it achieved the average accuracy of 97.3% of optic disc and 88.1% of optic cup. Detection rate of glaucoma diesis is 96.75

Trajectory-based interpretation of laser light diffraction by a sharp edge

In the diffraction pattern produced by a half-plane sharp edge when it obstructs the passage of a laser beam, two characteristic regions are noticeable. There is a central region, where it can be noticed the diffraction of laser light in the region of geometric shadow, while intensity oscillations are observed in the non-obstructed area. On both sides of the edge, there are also very long light traces along the normal to the edge of the obstacle. The theoretical explanation to this phenomenon is based on the Fresnel-Kirchhoff diffraction theory applied to the Gaussian beam propagation behind the obstacle. Here we have supplemented this explanation by considering electromagnetic flow lines, which provide a more complete interpretation of the phenomenon in terms of electric and magnetic fields and flux lines, and that can be related, at the same time, with average photon paths.Comment: 13 pages, 5 figure

In Vitro Release of Metal Ions from a Gold-Platinum Alloy in Saliva-Simulated Conditions

The aim of this study was to evaluate the behavior of high-noble gold-platinum alloy samples (18+8 Rafinerija plemenitih kovina, Zagreb, Hrvatska), in a phosphate buffer pH 6.0. The aim of the study was to determine the type and amount of released metal ions from the alloy, and to evaluate how the time of exposure to the phosphate buffer pH 6.0 influences the release of metal ions from the alloy. Manufacturer samples 8.06.5 1.0 mm in size, with a surface area of 133mm2 were used. The release of metal ions from the tested alloy was measured in ten time periods (after 1, 2, 3, 4, 5, 6, 7, 14, 21 and 30 days). Six samples were used (n=6) for each time period that the alloy was in the solution, which means that a total of 60 samples was analyzed. Solutions, in which the samples were placed, were analyzed with the inductively coupled plasma atomic emission spectrometer (ICP-AES, JY 50P, Jobin-Ywon, France). It was found that four metal ions were released: zinc ions (Zn), chromium ions (Cr), copper ions (Cu) and iron ions (Fe). The most released ions from the gold-platinum alloy were those of zinc (Zn), and the least released were those of iron (Fe) (p<0.01). The results of the study show that the time the tested alloy spent in the phosphate buffer pH 6.0 solution has an effect on the release of ions (p<0.01)

Evaluation of Periodontal Parameters in Patients with Early Stage Chronic Lymphocytic Leukemia

Svrha rada: Procjenjivao se parodontni status ispitanika s KLL-om u ranom stadiju i uspoređivao s parodontnim statusom zdravih ispitanika u kontrolnoj skupini te analizirala veza između parodontoloških i hematoloških parametara bolesnika s KLL-om. Materijali i metode: Pregledano je 60 ispitanika: 30 oboljelih od KLL-a – u stadiju Rai 0 (ispitna skupina) te 30 zdravih osoba iste životne dobi (kontrolna skupina). Kriteriji za isključivanje bili su: postojanje neke druge sistemske bolesti ili stanja (npr. dijabetes), već provedena parodontna terapija, liječenje antibioticima tijekom posljednja tri mjeseca i uzimanje lijekova. Socijalno-demografski podatci prikupljeni su upitnikom. Ispitanicima s najmanje osam zuba obavljen je kompletan parodontološki pregled i određeni su API, PBI, PPD, REC i CAL. Medicinski podatci oboljelih od KLL-a preuzeti su iz njihove medicinske dokumentacije, a hematološki parametri očitani su iz nalaza krvne pretrage. Rezultati: Skupine su se međusobno razlikovale s obzirom na dob, broj zuba i učestalost odlazaka stomatologu (p 0,05), nego samo za REC (F = 4,601; p 0,05). Zaključak: Rezultati ovog istraživanja pokazali su da su oboljeli od KLL-a imali lošiji parodontni status negoli zdravi ispitanici. Uzročno-posljedična veza između parodontoloških i hematoloških parametara nije dokazana.Objective: To assess periodontal conditions in patients with early stage CLL and to compare it with the periodontal status of age matched healthy controls and to analyze the relationship between periodontal and hematological parameters in CLL patients. Materials and Methods: 60 subjects were examined: 30 patients with CLL Rai 0 (test group) and 30 age-matching healthy individuals (control group). The exclusion criteria were: presence of other systemic disease or condition (e.g. diabetes), history of treatment for periodontitis, use of antibiotics during the last 3 months, use of medications. Socio-demographic data were obtained by means of a questionnaire. Participants with at least 8 teeth underwent a full mouth examination assessing API, PBI, PPD, REC and CAL. Medical data for CLL patients were collected from the patients’ records, while hematological data were obtained from the hemogram. Results: Difference between groups was statistically significant for age, number of teeth and frequency of dental checkups (p0.05), only for REC (F=4.601; p0.05). Conclusion: The results of this study showed that patients with CLL had worse periodontal status compared to healthy subjects. Causal relationship between periodontal and hematological parameters was not proved

Influence of Smoking on the Periodontal Status of Adolescents

Mnoga su istraživanja potvrdila da je pušenje jedan od najvažniji čimbenika rizika za nastanak, progresiju i uspješnu terapiju parodontalne bolesti. No samo je nekoliko istraživanja provedeno da bi se utvrdio utjecaj pušenja na mlađu populaciju. Poznato je da je težina parodontalne bolesti izravno povezana s dnevnom količinom cigareta, ali i s godinama pušenja. Potrebno je prepoznati prve znakove negativna utjecaja kako bi se moglo djelovati. Svrha ovoga istraživanja bila je odrediti postotak pušača među učenicima, utvrditi ima li razlike u parodontalnom statusu pušača i nepušača, te ustanoviti utjecaj pušenja na gubitak pričvrstka. Istraživanje je provedeno na 517 srednjoškolskih učenika. Uzimani su podatci o dobi, mjestu stanovanja. socijalnom statustu, navici pušenja, navici pušenja roditelja, navikama oralne higijene i posjeta stomatologu. Parodontalni se je status prikupljao s pomoću CPI i LA indeksa. 34,6% ispitanika bili su redoviti pušači. Dob u kojoj srednjoškolci počinju pušiti sve je niža. Oni koji sada imaju 16 godina počeli su pušiti s 14, ali oni koji sada imaju 14 i 15 godina počeli su pušiti s 12. Djeca kojima roditelji puše imaju dvostruko veću vjerojatnost da i sami postanu pušači, u usporedbi s onom djecom kojoj roditelji ne puše. Krvarenje je češće u pušača (4,61) nego nepušača (4,19) (p=0,001).Pušači imaju znatno više sekstanata s kamencem (1,47) nego nepušači (0,88) (p<0,001). Gubitak pričvrstka znatno je veći u pušača (1,68) nego nepušača (,59) (p<0,001). Količina popušenih cigareta ima velik utjecaj na gubitak pričvtstka. Godišnji gubitak pričvrstka u redovitih i jakih pušača iznosi 0,07 mm. Navike oralne higijene ne razlikuju se između pušača i nepušača, ali učenici s lošom oralnom higijenom imaju veći gubitak pričvrstka. Pušenje utječe na parodontalnu bolest, čak i u mladoj populaciji. Zato je prijeko potrebno obavijestiti mlade pušače o negativnim posljedicama te navike.Different studies have proven that smoking is one of the most important risk factors for the occurrence, progression and successual therapy of periodontal disease. However, only few studies have been conducted to prove the influence of smoking in a younger population. As we know that the severity of periodontal disease is directly associated with the amount of daily smoked cigarettes and also with the duration of smoking, it is important to find out when the first signs of negative influence appear so that we can act appropriately. The aim of this study was to determine if the periodontal status of smokers and non-smokers has differences, and to establish the influence of smoking habits on loss of attachment.The study was conducted on 517 highschool students. For each examinee data was taken concerning their age, place of residence, social status, smoking habits, smoking habits of their parents, oral hygiene habits and attendance to a dentist. The periodontal status was measured by the CPI and LA indices. Among the examines 34.6% were regular smokers. Students who are now 16 started to smoke when they were 14, but students who are now 14 and 15 started at age of 12. Children whose parents smoke had a two-fold increase of becoming smokers themselves, compared to children whose parents did not smoke. Bleeding was more frequent in non-smokers (4.61), than in smokers (4.19) (p=0,001). Smokers had significantly more sextants with calculus (1.47) than nonsmokers (0.88) (p<0,001). Loss of attachment was significantly greater in smokers (1.68) than in non-smokers (1.59) (p<0.001). The amount of smoked cigarettes had a great influence on loss of attachment. The annual loss of attachment in regular and intensive smokers measured 0.07 mm. Oral hygiene habits did not differ between smokers and non-smokers, but students with poor oral hygiene habits had greater attachment loss. Smoking has an influence on periodontal health even in this young age population, therefore it is necessary to inform young smokers about the negative cosequencese that smoking has

Comparison of the Bond Strengths of Zinc Phosphate, Glass-Ionomer, and Compomere Cement for Dowel Cementation

Unatoč dosad mnogim provedenim istraživanjima, ne postoji jedinstvena ocjena koji je cement najbolji za cementiranje konfekcijskih kolčića. Svrha rada bila je ispitati i usporediti retenciju konfekcijskih kolčića cementiranih s trima različitim vrstama cemenata: cink-fosfatnim, stakleno-ionomernim i kompomernim. Prikupljeno je 30 zuba i endodontski preparirano do dubine od 7 mm i ISO promjera 140. Podijeljeni su u 3 skupine od 10 uzoraka. S pomoću triju navedenih vrsta cemenata u njih su cementirani kolčići od čelične žice. Pošto se je cement stvrdnuo, izmjerena je vlačna sila potrebna za izvlačenje kolčića iz korijenskoga kanala. Za cink-fosfatni cement iznosila je 175±33,17 N, za stakleno-ionomerni 235,5±46,93 N, a za kompomerni 275,63±96,42 N. Kolčići cementirani kompomerom imaju znatno jaču retenciju od kolčića cementiranih cink-fosfatnim ili stakleno-ionomernim cementom. Stakleno-ionomerni cement mnogo jače retinira od cink-fosfatnoga cementa. Prednosti cink-fosfatnog cementa jesu manja osjetljivost na pogrješke u radu i razmjerna jeftinoća, te još uvijek u mnogim kliničkim okolnostima ostaje cement izbora.In spite of numerous previous studies, there is no final conclusion on which type of cement is the best for dowel cementation. The purpose of this study was to compare the retention of dowels cemented with three different cement types: zinc phosphate, glass-ionomer, and compomere. Thirty teeth were divided into 3 groups, root-canals were prepared to ISO 140, to 7 mm depth and dowels were cemented. After 40 hours the tensile force needed to dislodge the dowels was recorded. For zinc phosphate it was 175±33.17 N, for glass-ionomer 235.5±46.93 N, and for compomere 275.63±96.42 N. The dowels cemented with compomere had significantly higher tensile strength than those cemented with zinc phosphate or glass-ionomer cement. Glass-ionomer cement had significantly higher tensile strength than zinc phosphate cement. The advantages of zinc-phosphate are its low price and simple usage. Thus, in many clinical situations it may be the cement of choice