Bioprogressive Therapy and Diagnostics

Bioprogresivna tehnika jest fiksna ortodontska tehnika nastala 1950- -tih godina na temelju edgewise tehnike. Njezin je utemeljitelj Robert Murray Ricketts. Ovaj rad donosi kratak pregled povijesti fiksne ortodoncije, objašnjava nastanak i razvoj Rickettsove tehnike, načela na kojima se temelji i metode kojima se ta tehnika koristi. Naglašen je Rickettsov doprinos ortodontskoj dijagnostici, predviđanju rasta pri planiranju i provedbi ortodontske terapije, a Rickettsova je bioprogresivna “filozofija”, kako ju zove sam autor, dovedena u kontekst i vezu sa suvremenim ortodontskim tehnikama.The bioprogressive technique is a fixed orthodontic technique, developed in the 1950s by Robert Murray Ricketts. This article provides a brief overview of the history of orthodontic practice, explaining the development of “Ricketts technique”, methods and principles that are incorporated in his bioprogressive therapy. It also discusses the importance of diagnostic methods, introduced by the author, that are still recognized as an important part of orthodontic therapy planning. This article explains the influence of bioprogressive philosophy on modern orthodontic techniques

Finite Element Method Stress Analysis Caused by Orthodontic Forces

Metoda konačnih elemenata pokazala se uspješnom u raščlambi prijenosa sila i naprezanja u biološkim sustavima. Svrha ovoga istraživanja bila je utvrditi razlike u distribuciji naprezanja i deformacija, ovisno o različitoj razini uporabe jednostavne vodoravne oralno usmjerene sile na labijalnu plohu zuba na matematičkom modelu zuba s pripadajućim potpornim strukturama napravljenom s pomoću metode konačnih elemenata. Kao predložak za izradbu modela poslužio je gornji očnjak izvađen iz parodontoloških razloga. Dobiven je trodimenzionalni model koji se sastoji od 4000 elemenata oblika heksaedra i 2367 čvorova, što čini ukupno 7101 stupanj slobode. Na model je upotrebljena vodoravna oralno usmjerena sila jakosti 1 N na pet različitih razina krune zuba, okomito na njegovu uzdužnu os. Za sva uporabljena opterećenja promatrana je deformacija, intenzitet naprezanja, te su izračunana ekvivalentna naprezanja po energetskoj teoriji čvrstoće (Huber- Mises- Hencky teorija).The method of finite elements has proved to be successful for analysis of the transmission of forces and stress in biological systems. The aim of this investigation was to determine differences in the distribution of stress and deformation, depending on different levels of application of simple horizontal orally directed forces on the labial surface of the tooth using a mathematical model of the tooth, with equivalent supportive structures, constructed means of the finite element method. An upper canine, extracted for periodontal reasons, was used as a pattern for construction of the model. A three-dimensional model was obtained consisting of 4000 elements in the shape of a hexahedron and 2367 nodes, totalling 7101 grades of freedom. Horizontal orally directed 1 N force, was applied to the model on five different levels of the tooth crown, vertically on its longitudinal axis. Deformation and stress intensity were observed for all the applied forces and equivalent stress calculated, according to the energetic theory of strength (Huber-Mises- Hencky theory)

Qualitative Analysis of the Enamel Surface After Removal of Remnant Composite

Postupak čišćenja zaostatnoga kompozita pošto je skinuta ortodontska bravica, problem je jer se često ošteti caklinska površina. Svrha je ovoga rada odrediti metodu čišćenja zaostatnoga kompozita koja najmanje oštećuje caklinsku površinu. Istraživanje je provedeno in vitro, na 30 premolara. Bravice su lijepljene i skidane istim postupkom, nakon čega su zubi nasumce podijeljeni u tri skupine. Prva je čišćena Band Driverom, druga tungsten karbidnim svrdlom, a treća klijeπtima za skidanje kompozita. Uzorci su analizirani svjetlosnim stereomikroskopom Olympus. Provedena je raščlamba mikrofotografija i procijenjen Surface Roughness Index (SRI). Najmanje izgrebana površina cakline ostala je nakon tungsten karbidnoga svrdla. Ono se je pokazalo najneškodljivijim sredstvom za čišćenje površine cakline od zaostatnoga sloja kompozita nakon skidanja ortodontskih bravica.Choosing the method of remnant composite removal after debonding is a problem, because most techniques cause deep scratches on the enamel surface. The purpose of this study was to determine the method that causes the least damage to the enamel. The study was carried out on a sample of 30 premolars. After brackets had been bonded and debonded, using the same procedure, the samples were divided at random into three groups. The composite remnants in the first group were removed using the Band Driver, in the second group using a tungsten carbide bur and in the third group using composite removing pliers. The samples were analysed using a light stereomicroscope (Olympus). The photomicrographs were graded and the SRI (Surface Roughness Index) “calculated”. The best enamel surface appearance was determined after using the tungsten carbide bur, which is considered the method which causes the least damage to the enamel surface

Dentoalveloar Compensatory Mechanism in Skeletal Open Bite

Svrha istraživanja bila je utvrditi morfološke značajke u ispitanika sa skeletnim otvorenim zagrizom, odnosno povećanim mandibularnim kutom povezanost dubine prijeklopa s vrijednostima veličine kuta mandibularne baze, kuta maksilarne baze i međučeljusnoga kuta povezanost dubine prijeklopa s vrijednostima prednje i stražnje visine lica, te dentoalveolarne kompenzatorne mehanizme kod okomitoga tipa rasta. Uzorak se sastojao od 77 laterolateralnih rentgenkefalograma ispitanika sa skeletnim otvorenim zagrizom, obaju spolova, dobi od 13 do 18 godina. Utvrđeno je da 49,4% ispitanika ima otvoreni zagriz a 50,6% ispitanika je kompenzirano, tj. da 41,5% ima normalni prijeklop, a 9,1% duboki zagriz. Ne postoji povezanost dubine prijeklopa s vrijednostima veličine kutova koje čine maksilarna i kranijalna baza, mandibularna i kranijalna baza, te međučeljusnoga kuta. Prednja donja visina (spa-gn) i ukupna prednja visina lica (n-gn) statistički su znatno manje u skupini ispitanika s dubokim prijeklopom. U skupini ispitanika s dubokim zagrizom prona|eno je statistički znatno smanjena udaljenost vrha kvržice gornjega prvog molara i apeksa od baze maksile.The object of the study was to determine morphologic characteristics in subjects with skeletal open bite and increased mandibular angle; correlation between the depth of the over bite and values of the size of the angle of the mandibular base, maxillary base and intermaxillary angle; correlation between the depth of the over bite with values of anterior and posterior facial height and dentoalveolar compensatory mechanism in vertical type growth. The sample consisted of 77 laterolateral cephalograms of subjects with skeletal open bite of both genders, aged from 13 to 18 years. It was determined that 49.4% of the subjects had open bite, while 50.6% of the subjects were compensated, i.e. 41.5% had normal over bite and 9.1% deep bite

Prevalence of Malocclusion in Patients with Down’s Syndrome

U osoba s Downovim sindromom pronađene su znatne promjene koje zahvaćaju kranioorofacijalno područje. Ovim radom željela se utvrditi čestoća pojedinih vrsta ortodontskih anomalija u tih ispitanika. U tu svrhu pregledano je 112 ispitanika s citogenetski potvrđenom dijagnozom Downova sindroma. Svi ispitanici podvrgnuti su potpunom stomatološkom pregledu. Za određivanje ortodontske anomalije uporabljena je sljedeća klasifikacija: kompresije, anomalija preranoga gubitka, progenija, otvoreni zagriz, pokrovni zagriz, jednostrani unakrsni zagriz, te obostrani unakrsni zagriz. U 92% ispitanika postojala je ortodontska anomalija. Najzastupljenija je bila progenija, i to u 43,8% ispitanika. Zbijenost i jednostrani križni zagriz pronađeni su svaki od njih u 17% ispitanika. Obostrani križni zagriz pronađen je u 5,4% ispitanika, anomalija preranoga gubitka samo u 1% ispitanika, a pokrovni zagriz nije pronađen ni u jednome slučaju.Significant alterations of the cranio-orofacial region have been observed in subjects with Down’s syndrome. The aim of this study was to assess the frequency of particular orthodontic malocclusion in these subjects. A group of 112 subjects with cytogenetically confirmed diagnosis of Down’s syndrome was examined. All the subjects underwent a complete dental examination. The following classification was used to determine malocclusion of crowding, premature tooth loss, class III malocclusion, open bite, class II division 2 malocclusion, unilateral cross bite and bilateral cross bite. Clipper language programs were designed for data processing. Malocclusion was found in 92% of the subjects. Class III malocclusion was most frequently observed (43.8%). Crowding and unilateral cross bite were found in 15% of the subjects respectively. Bilateral cross bite was present in 5.4% of the subjects. Premature tooth loss was observed in only 1% of the subjects whereas class II division 2 malocclusion was not recorded in any of the subjects examined

Variations of Mandibular Variables in Skeletal Orthodontic Anomalies

Svrha istraživanja bila je odrediti: veličinu mandibularnoga kuta, visinu ramusa i dužinu mandibularnoga korpusa, te usporediti dobivene rezultate ovisno o tipu skeletne ortodontske anomalije, dobi i spolu ispitanika. U istraživanju je sudjelovalo 77 ispitanika (30 muških, 47 ženskih) -s dijagnosticiranim anomalijama otvoreni zagriz, progenija i pokrovni zagriz- koji su svrstani u tri dobne skupine. Na laterolateralnim rengenkefalogramima izmjerene su sljedeće varijable: mandibularni kut, visina ramusa i dužina mandibularnoga korpusa. Mandibularni kut bio je najmanji u ispitanika s pokrovnim zagrizom (prosječno 123°), najveći u pacijenata s otvorenim zagrizom (prosječno 135°), a u ispitanika s progenijom iznosio je prosječno 130°. Postoji statistički znatna razlika između veličine mandibularnoga kuta i vrste anomalije (p<0,05). Dokazano je da postoji statistički znatna razlika između linearnih skeletalnih varijabli i dobnih skupina (p<0,05). Kod vrijednosti visine ramusa i dužine mandibularnoga korpusa statistički znatna razlika postoji između prve (6-12 god.) i treće (16-18 god.) dobne skupine (p<0,05). U ispitanika su vrijednosti linearnih skeletnih varijabli više od istih varijabli izmjerenih u ispitanica, no razlika nije statistički znatna.The object of the study was to determine the size of the mandibular angle, height of the ramus and length of the mandibular corpus, and to compare the obtained results, depending on the type of skeletal orthodontic anomaly, age and gender of the subject. Seventy-seven subjects participated in the study (30 male and 47 female) with diagnosed anomalies of open bite, mandibular prognathism and Class II/2 malocclusion, classified into three age groups. The following variables were measured on a laterolateral cephalometric radiograph: mandibular angle, height of the ramus and length of the mandibular corpus. The mandibular angle was smallest in the subjects with over bite (average 123°), largest in patients with open bite (average 135°) and in subjects with progeny it amounted to an average 130°. Statistically significant difference was found between the size of the mandibular angle and the type of anomaly (p<0.05). Statistically significant difference was determined between linear skeletal variables and age groups (p<0.05). With regard to the values of the height of the ramus and length of the mandibular corpus statistically significant difference was found between the first age group (6-12 years) and the third age group (16-18 years) (p<0.05). In the male subjects values for linear skeletal variables were higher than the same variables measured in female subjects, although the difference was not statistically significant

Stereomicroscope Analysis of Enamel Surface after Orthodontic Bracket Debonding

After orthodontic brackets debonding, the remaining resin has to be removed. The purpose of this study was to determine the most efficient method as well as to introduce a new method of composite removal. The study was carried out on a sample of 30 premolars, extracted for orthodontic purposes. Brackets had been bonded using the Ortho One Bisco composite resin. After the removal of brackets, samples were randomly divided into three groups of ten. Composite remnants in the first group were removed using the Band Driver (KaVo). For the second group, the tungsten carbide bur (Komet) was applied. In the third group, composite remnants were removed manually, using adhesive removing pliers (ORMCO). The samples were analysed using a light-stereomicroscope (Olympus). Photomicrographs were examined and the ARI (Adhesive Remnant Index) was calculated. Post Hoc tests (Scheffe, Tukey) indicated a statistically significant difference between groups 1 and 2 as well as between groups 1 and 3. The tungsten carbide bur was found to be the most efficient instrument for composite remnant removal

HEALTH ACTIVITIES AS A PUBLIC SERVICE

Javne službe su djelatnosti koje se obavljaju u javnom interesu pod posebnim pravnim režimom. Njima se zadovoljavaju potrebe građana, te su djelatnosti javnih službi vrlo široke i različite. Stoga, ovaj završni rad, pored temeljnih pojmova vezanih za javne službe, obrađuje zdravstvenu djelatnost kao javnu službu. U radu se analiziraju pojedina bitna pitanja zdravstva kao što su organizacija zdravstvene djelatnosti, zatim sama zdravstvena djelatnost, kadrovi u zdravstvu i financiranje