Contact Sensitivity to Dental Prosthetic Materials - Alloys

Reakcije tipa IV, ili reakcije kasne preosjetljivosti, jedna su od manifestacija stanične imunosti. Te su reakcije uzrokovane specifično senzibiliziranim T-limfocitima. U stomatologiji posebice zanimljiva kontaktna preosjetljivost. Nadomjestci su u dugotrajnom izravnom doticaju s oralnim tkivima i slinom, a ujedno se u funkciji troše i savijaju. Ta zbivanja dovode do korozivnih procesa koji rezultiraju oslobađanjem iona, njihovom akumulacijom u tkivima i mogućom senzibilizacijom, to jest alergijskom reakcijom. Stomatolozi bi u svojemu radu trebali birati slitine s manjom tendencijom otpuštanja iona, odnosno dobre biosnošljivosti. Preporuča se izbjegavati uporabu slitina s visokim udjelom nikla. Epikutani (patch) test indiciran je u svakoga pacijenta koji u svojoj povijesti bolesti navodi preosjetljivost na kovine ili druge materijale koji će se upotrijebiti za izradbu protetskoga nadomjestka.Type IV reactions, reactions of delayed hypersensitivity, are manifestations of cellular immunity. Such reactions are caused by sensitised T-lymphocytes. In dental medicine contact sensitivity is of particular interest, as restorations are in long-term direct contact with oral tissues and saliva and during function they wear and bend, leading to corrosive processes which result in the release of ions, their accumulation in the tissues and possible sensitivity, i.e. allergic reaction. Dentists need to chose alloys with less tendency to the release of ions, in other words good biotolerance. It is recommended that the use of alloy with a high share of nickel should be avoided. Patch test is indicated for all patients with a history of hypersensitivity to metal or other materials used in the construction of a prosthetic restoration

Glass-Ceramics

Staklokeramika je polikristalni materijal koji nastaje kontroliranom kristalizacijom stakla. Tijekom kontrolirane, upravljane kristalizacije stakla nastaje dvofazni materijal; kristali i amorfna staklena matrica. Nastanak kristala, veličine nekoliko mikrometara, događa se kod postupka temperiranja sveukupnoga volumena stakla, stvaranjem klica i rastom kristala. Klice su ili latentno postojeće u staklu ili se dodaju kao netopljiv materijal u fino dispergiranoj podjeli mješavine (staklenoj amorfnoj masi). Postoje sustavi staklokeramike za laboratorijsku izvedbu i za strojno glodanje gotovih keramičkih blokića. Iskorištavanjem postupka lijevanja i vrućega tlačenja staklokeramike dobili su sematerijali s izvrsnim mehaničkim i estetskim svojstvima za izradbu nesamo pojedinačnih krunica, inlaya, onlaya već i tročlanih mostova.Glass ceramics is a polycrystal material which is obtained by controlled crystallisation of glass. During the controlled crystallisation of glass a two-phase material emerges: crystals and an amorphous glass matrix. The development of crystals, several micrometers in size, takes place during the procedure of heating the total volume of glass, formation of germs and growth of crystals. The germs are either latently present in the glass or are added as an insoluble material in the finely dispersed distribution of the mixture (glass amorphous mass). Glass ceramic systems exist for laboratory fabrication and machine milling of finished ceramic blocks. By the method of casting and heat pressing glass ceramics materials are obtained with excellent mechanical and aesthetic properties for fabrication single crowns, inlays and onlays and also of three-unit bridges

The Role of Psycho-Emotional Tension and Stress in the Etiology of Bruxism

Uzrok bruksizma još uvijek nije potpuno razjašnjen. U literaturi se kao glavni etiološki čimbenik navodi psihogena sastavnica. Ovim radom pokušalo se je ocijeniti udio stresa, psihoemocionalne napetosti i anksioznosti u etiologiji bruksizma te ispitati povezanost nekih psihosomatskih simptoma s bruksizmom. Opažena je statistički znatna razlika (p<0,02) u rezultatima testa anksioznosti i podložnosti stresu između skupine ispitanika s bruksizmom i kontrolne skupine te je zaključeno da u pacijenata s bruksizmom postoji veća razina psihoemocionalne napetosti, stresa i anksioznosti. U skupine ispitanika s bruksizmom uočena je veća čestoća nekih psihosomatskih simptoma (tahikardija, palpitacije) u odnosu prema kontrolnoj skupini, p<0,01. Rezultati upozoravaju na važnost psihosomatskih čimbenika u etiologiji bruksizma.The cause of bruxism is still unknown. The most commonly referred factor in the etiology of bruxism is that of psychogenic origin. This study was an attempt to evaluate the role of stress, psycho emotional tension and anxiety in the etiology of bruxism. The aim was also to determine a connection between certain psychosomatic symptoms and bruxism. The analysis showed statistically significant difference (p < 0.02) in the results of the anxiety and stress test between the bruxism group and the control group. It was concluded that there is a higher level of psychoemotional tension, stress and anxiety in patients with bruxism. Higher frequency of psychosomatic symptoms (tachycardia, palpitation) was also present in the group with bruxism than in the control group (p<0.01). These results point out the importance of certain psychosomatic factors in the etiology of bruxism

Bruxism: An Unsolved Problem in Dental Medicine

Bruksizam je stanje za koje se može reći da prati čovjeka gotovo od njegova postanka - od barbarskih vremena, do današnjega modernog, stresom opterećenog čovjeka. Prema American Dental Association, čestoća bruksizma danas varira od 5 do 20 %. Velik raspon incidencije može se objasniti upravo činjenicom da osamdeset posto ljudi koji imaju neki oblik škripanja ili stiskanja zubima nije svjesno te parafunkcije svojega stomatognatog sustava. O tome je napisano mnogo radova, ali rezultati su još uvijek kontradiktorni. Pojavljuju se različite inačice uvriježenih pretpostavki i pokušaja rješavanja osnovnih problema - etiologije i terapije bruksizma, no najveći problem, bruksizam u svakodnevnoj stomatološkoj praksi, često ostaje neprepoznat ili neadekvatno liječen.Bruxism exists as long as humanity; since barbarian times, through the Bible and christianity until the modern stressful age. According to American Sleep Disorders Association, the prevalence of bruxism varies from 5 to 20 per cent. This difference can be related to the lack of awareness in eighty per cent of the popullation that has some form of teeth clenching and/or grinding. Many studies have been published, but the results are still contradictory. There is a large scale of different etiological and therapeutical approaches presented in the scientific literature, but the main problem - bruxism in every day practice often remains undetected and badly treated

Investigation of Contact Allergies to Component and Auxiliary Prosthetic Materials

Kontaktna alergija je odgođena reakcija preosjetljivosti u kojoj se lokalizirana lezija kože ili sluznice javlja zbog opetovanoga doticaja s alergenom. Od fiksnog ili mobilnoga protetskog rada u usnoj šupljini nastaju korozijski procesi na površini nadomjestka te otpuštanja iona koji, kao hapteni, mogu pokrenuti alergijsku reakciju. Svrha ovoga istraživanja bila je epikutanim alergološkim testom ispitati pojavnost alergije na gradivne i pomoćne protetske materijale u pacijenta s lihen ruber planusom, stomatitisom i stomatopirozom. U istraživanju su sudjelovala 32 pacijenta s fiksnim i/ili mobilnim nadomjestkom i 7 pacijenata s jednom od navedenih dijagnoza bez nadomjestaka. Ispitivanje je provedeno standardnom tehnikom (patch testom) na 13 alergena. Rezultati istraživanja pokazuju veću vjerojatnost na pozitivan patch test u osoba s navedenim bolestima i s nadomjestkom u usporedbi s ispitanicima bez nadomjestaka (P = 0,62). Pričvršćenjem fiksnog ili postavljanjem mobilnoga nadomjestka raste vjerojatnost da će se simptomi pogoršati (P = 0,019), a pogotovo ako se radi o nadomjescima od Co-Cr-Mo slitine. Povećanjem broja članova fiksnih nadomjestaka, ili pak postojanjem mobilnih nadomjestaka u objema čeljustima, raste i vjerojatnost pozitivnoga rezultata patch testa na kobaltni klorid (P = 0,05). Lichen ruber planus povećava vjerojatnost na pozitivan patch test u najvećem broju slučajeva (P = 0,05). Najviše pozitivnih rezultata bilo je na alergene nikla, kobalta i kroma (svaki 17,95%), a negativan nalaz dobiven je kod dibutilftalata i HH smjese. Stomatopiroza povećava vjerojatnost da ispitanik ima pozitivan rezultat testiranja na krom (P = 0,019). U žena je pojava pozitivnoga patch testa veća na sve alergene (P = 0,05) osim na epoksidne smole, kod kojih je manja nego u muških ispitanika (P = 0,036). Zbog sve češće kontaktne alergije u populaciji potrebno je provesti potanka ispitivanja protetskih materijala prije nego što ih se uvede u kliničku praksu, a u pacijenata s atopijskom anamnezom alergološka testiranja i imunološke testove prije protetske sanacije.Contact allergy is a delayed reaction to sensitivity in which a localised lesion of the skin or mucous membrane occurs as a result of contact with an allergen. The fitting of a fixed, or placement of a mobile, prosthetic appliance in the oral cavity causes corrosive processes to occur on the surface of the restoration and the release of ions which, as haptens, can induce allergic reaction. The aim of this investigation was to examine the occurrence of allergies to component and auxiliary prosthetic materials by patch test in patients with lichen ruber planus, stomatitis and stomatopyrosis. Thirtytwo patients with fixed and/or mobile restorations and seven patients with one of the above diagnoses without a restoration, participated in the investigation. Testing was carried out by standard technique (patch test) with 13 allergens. The results of the investigation indicate the greater probability of a positive patch test in subjects with the aforementioned diseases and with a restoration, in relation to subjects without a restoration (P = 0.62). The probability of symptoms worsening increased with the insertion/ fitting of a fixed or placement of a mobile restoration (P = 0.019). This was particularly so in the case of restorations made of Co-Cr-Mo alloy. With the increase in the number of units of fixed restorations, or the presence of mobile restorations in both jaws, the probability of a positive patch test to cobalt chloride also increased (P = 0.05). Lichen ruber planus increased the probability of a positive patch test in the majority of cases (P = 0.05). The greatest number of positive results were for the allergens nickel, cobalt and chrome (each 17.95%) and a negative finding was obtained for dibutylphthalate and HH mix. Stomatopyrosis increased the probability that the subject would have a positive result for chrome (P = 0.019). The occurrence of a positive patch test was greater in women for all allergens (P = 0.05), apart from epoxy resin, where it was less than in the male subjects (P=0.036). Because of the greater incidence of contact allergies in the population a more detailed investigation of prosthetic materials is needed prior to their introduction into clinical practice. In the case of patients with atopic history allergological testing and immunological tests should be performed prior to prosthetic treatment

The Release of Metal Ions in the Gingival Fluid of Prosthodontic Patients

Korozija nadomjestka i njegovo trošenje u funkciji zatvaraju krug koji uzrokuje oštećenje nadomjestka i štetne reakcije na okolnome tkivu ili čak na udaljenim organima. Svrha ovoga istraživanja bila je identificirati ione Au, Pt, Ag i Pd u sulkusnoj tekućini (ST) u fiksnoprotetskih pacijenata i odrediti masu iona u dobivenom uzorku. U istraživanju je sudjelovalo 20 ispitanika, od toga 15 je imalo fiksne nadomjestke i isti stupanj higijene, a 5 nije imalo nikakav protetski rad te su poslužili kao kontrolna skupina. Nadomjesci su bili izrađenih od slitina Au − Pt, Au − Pt, Ag − Pd i Ni − Cr te pričvršćeni u ustima: - od 1-14 dana, i 3-8 godina. Uzorci su dobiveni ulaganjem adsorbcijskoga papirića (AP) u gingivni sulkus (GS) zuba nosača u vremenu od deset minuta. AP s uzorkom ST analizirani su s pomoću spektrometra masa s induciranom združenom plazmom (ICP-MS). Rezultati su statistički obrađeni programskim paketom SPSS, a upotrijebljena je deskriptivna statistika i korelacija uzoraka. U cijelome uzorku statistički se znatno povezane koncentracije Ag, Au i Pt, a koncentracija Pd ponaša se prema vlastitu uzorku. Raščlambom rezultata u kontrolnoj skupini nije utvrđena statistički znatna povezanost za iste međuodnose. U podskupini Ag-Pd slitine utvrđena je statistički znatna povezanost između koncentracija Ag, Au i Pd, a najizrazitija je veza između koncentracija Au i Pd. Postoji statistički znatna razlika u koncentraciji Pt između podskupina s novim radovima s najvišom vrijednosti u skupini slitina Au (P=0,023) u usporedbi s kontrolnom skupinom.Utvrđena je statistički znatna promjena vrijednosti Ag (P=0,011) i Pt (P=0,039) s padom vrijednosti obiju tih kovina u ispitanika sa starim protetskim radovima.Corrosion of prosthetic restorations and simultaneous wear during usage leads to damage of the restoration and harmful reactions on the surrounding tissues or even on distant organs. The aim of this study was to identify the ions Au, Pt, Ag and Pd in the gingival fluid of patients with fixed prosthetic appliances and to determine the mass of ions in the obtained sample . The study included 20 subjects: of which 15 had fixed prosthetic appliances and the same level of hygiene, and 5 without have any prosthetic appliances, who served as a control group. The prosthetic appliances were made from alloy compounds: Au - Pt, Au - Pt, Ag - Pd, Ni - Cr, fixed in the mouths: from 1-14 days, and 3-8 years. Samples were obtained by placing adsorbent paper (AP) in the gingival sulcus (GS) of the abutment tooth for a period of ten minutes. AP with samples gingival fluid (ST) were analysed by means of a mass spectrometer with fused plasma (ICP-MS). The results were statistically analysed by the programme packet SPSS, with descriptive statistics and correlation of samples. In the whole sample statistically significant correlation was found for the concentrations of Ag, Au and Pt, while the concentration of Pd was characteristic for each sample. Analysis of the results in the control group did not reveal statistically significant correlation for the same inter-relations. In the sub-group Ag-Pd alloys statistically significant correlation was established between the concentrations of Ag, Au and Pd, and the most marked correlation found was between the concentrations of Au and Pd. Statistically significant differences were determined in the concentrations of Pt between the subgroups with new appliances, with the highest value in the group of Au alloy (P=0.023) in comparison with the control group. Statistically significant changes were determined in the values of Ag (P=0.011) and Pt (P=0.039), with a fall in the values of both metals in subjects with older prosthetic appliances

A Method for Testing Abrasive Wear of Aesthetic Prosthetic Materials

Trenje i trošenje zbivaju se na dodiru tvarnih površina koje su više ili manje hrapave. Tijekom abrazijskoga trošenja nastaje istiskivanje materijala prouzročenog tvrdim česticama koje prave pritisak prema površini, ili kližu duž nje (trotočkasto abrazijsko trošenje), ili pak tvrdim izbočinama (dvotočkasto abrazijsko trošenje). Zahtjevi za estetskom opskrbom grizne plohe postavljaju pred kliničara problem izbora materijala za fasetiranje. U ovome članku opisana je metoda za ispitivanje abrazijskoga tro- šenja parova zub-protetski materijal za fasetiranje. Da bi se ocijenila ta metoda ispitana su dva različita protetska materijala za fasetiranje (polimerni materijal SR Chromasit, Ivoclar i glinična keramika, Sign Ivoclar) na modificiranom Taber abrazeru, u suhim uvjetima. Dobivene su znatne razlike u tragovima trošenja na uzorcima ispitivanih materijala. Testirana metoda omogućuje ispitivanje uzoraka različitih materijala međusobno ili u paru s prirodnim zubom, pod različitim opterećenjima te s postojanjem trećeg tijela ili bez njega (hrane ili umjetne sline), što je u kliničkoj praksi vrijedan podatak pri izboru vrste konstrukcije i materijala za fasetiranje.Friction and wear occur due to the contact of surfaces which are more or less rough. During abrasive wear the extrusion of material occurs, caused by hard particles which apply pressure toward the surface or slide along it (three-body abrasive wear) or by hard protrusions (two-body abrasive wear). Because of demands to provide a satisfactory aesthetic mastication surface the clinician is faced with the problem of the choice of material for veneering. The article describes a method for testing abrasive wear of pairs of tooth-prosthetic material for veneering. In order to test the method two different prosthetic veneering materials were tested (polymer material SR Chromasit, Ivoclar and Clay ceramic, Sign-Ivoclar) on a modified Taber abraser, in dry conditions. Significant differences were determined in the wear scars on specimens of the tested materials. The method enables the testing of specimens of different materials mutually or in a pair with a natural tooth, under different loading and with or without a third body (food or artificial saliva), which in clinical practice represents valuable data during the choice of the type of construction and veneering material

Factors Related to Oral Health Related Quality of Life in TMD Patients

The aims of the study were to determine the impact of temporomandibular disorders (TMD) on self-percieved oral health related quality of life (OHRQoL) and to compare OHRQoL of patients with TMD with a control group. A total of 81 TMD patients participated in a study group and 400 adults served as the control group. The mean OHIP summary scores were computed for all patients with the same diagnosis and the same subgroup of axis I according to the RDC/TMD exam form. The mean OHIP subscores for all seven domains of the OHIP questionnaire were compared between the study and the control group. The hierarchical linear regression model was used to assess the most important variables according to the RDC/TMD protocol that contribute to OHRQoL in TMD patients with the OHIP summary score as dependent variable. According to this study,TMD had a high association with reduced OHRQoL (p<0.001). More diagnoses of axis I according to the RDC/TMD protocol (p<0.001), higher age of TMD patients (p<0.001) and diagnoses associated with limited jaw movements contributed to more impaired OHRQoL (p=0.008 and p=0.030, respectively). Female TMD patients had no significantly different OHRQoL compared to male patients (p=0.436). According to regression analysis, higher age (p<0.001), more physical diagnoses (p=0.018) and diagnosis Ib (p=0.169) explained 39.1% of the variability (p<0.001) of the OHIP summary score in TMD patients

Analysis of Fixed Prosthetic Appliances in Patients living in the Metković Region, Croatia

Epidemiološke studije o stanju postojećih fiksnoprotetskih radova ili o potrebi za novim, a sa svrhom da se planiraju potrebni protetski timovi te poboljšaju materijali i postupci, prijeko su potrebni u suvremenoj protetici. Svrha rada bila je utvrditi koji je estetski materijal upotrijebljen za izradbu fiksnoprotetskih radova u pacijenata metkovićevske regije te utvrditi čestoću krunica i mostova ovisno o dobi, spolu, stručnoj spremi, zaposljenju, društveno-ekonomskom statusu i čestoći posjeta stomatologu. Pregledano je 212 pacijenata nositelja fiksnoprotetskih radova. Pregledi su izvedeni u Domu zdravlja Metković tijekom 2001. godine. Deskriptivna statistika i χ 2 testovi upotrijebljeni su prigodom statističke obradbe podataka. Izvedeni su sljedeći zaključci: Stariji pacijenti imali su znatno više mostova nego krunica (p0,05), niti između pacijenata različita stupnja naobrazbe (p>0,05). Umirovljeni pacijenti imali su znatno više mostova nego krunica u usporedbi sa zaposlenima ili nezaposlenima (p0,05). Pacijenti niske stručne spreme imali su više fiksnoprotetskih nadomjestaka starijih od 10 godina u usporedbi s pacijentima srednje ili visoke stručne spreme (p<0,01). Zabilježena je razmjerno česta upotreba keramike (64%) u usporedbi s polimernim materijalima (36%). Nije bilo razlike između spolova ovisno o materijalu za fasetiranje fiksnoprotetskoga rada (p>0,05). Pacijenti stariji od 60 godina i pacijenti niže stručne spreme imali su više polimernih fasetiranih radova od mlađih pacijenata (<39 godina) koji su imali uglavnom sve radove fasetirane keramičkim materijalima (p<0,01).Epidemiological studies on the condition of existing or the need for new fixed prosthodontic appliances, with the purpose of planning required prosthetic teams, improved materials and methods, are essential in modern prosthodontics. The aim of this study was to evaluate the aesthetic material used in patients with fixed prosthodontic appliances in the Metkovi} region and determine the frequency of crowns and bridges in relation to age, gender, level of education, employment, socio-economic status and frequency of regular visits to the dentist. examination The study included 212 patients, wearing fixed prosthodontic appliances, who were examined in the dental office (clinic) at the Metkovi} Medical Centre during 2001. Descriptive statistics and (2 tests were used during data analysis. The following conclusions were made: 1. The older group of patients had significantly more bridges than crowns (p0.05), or between patients of different levels of education (p>0.05). Retired patients had significantly more bridges than crowns compared to employed or unemployed patients (p0.,05). Less educated patients had more fixed prosthodontic appliances older than 10 years than better educated patients (p0.05). Patients older than 60 and less educated patients had more acrylic appliances than younger patients (<39 years) who had mainly only ceramic appliances (p<0.01)