Alterations of FHIT and P53 genes in keratocystic odontogenic tumor, dentigerous and radicular cyst

BACKGROUND: The purpose of this study was to determine fragile histidine triad (FHIT) and p53 protein expression, and to analyze FHIT and p53 gene status in keratocystic odontogenic tumor (KOT), dentigerous cysts (DC) and radicular cysts (RC). ----- METHODS: The methods used were immunohistochemistry and molecular genetic methods including loss of heterozygosity (LOH) and gene sequencing. ----- RESULTS: FHIT protein expression was different among groups. Aberrant expression was the highest in KOT, then in RC and DC. p53 protein expression was different among groups. LOH in paraffin-embedded specimens was detected in 22.6% and 12.9% for FHIT and p53 respectively. Mutation of p53 gene at codon 237 was observed in only two specimens (one KOT and one DC). Of the six frozen specimens, three exhibited FHIT gene LOH (two RC and one KOT). KOT showed loss of exons 6-7 at FHIT locus and mutation at codon 237 at p53 locus, but this could be a chance result. ----- CONCLUSION: Aberrations of FHIT and p53 genes/proteins could be considered markers responsible for the development of odontogenic lesions

Three-Rooted Maxillary First Premolars: Five Clinical Cases

Prvi gornji trokorijeni pretkutnjaci ne pojavljuju se često, ali njihovu pojavnost moramo imati na umu pri endodontskom tretmanu gornjih pretkutnjaka. Ulazi u bukalne korijenske kanale obično nisu dobro vidljivi, pa unatoč dobrom poznavanju anatomije, kliničkom iskustvu i radiografskoj snimci jedan od bukalnih kanala ostaje neobrađen. Incidencija prvih gornjih pretkutnjaka s tri odvojena korijena, tri kanala i tri apeksna otvora je između 4-6%. U radu je prikazano 5 endodontskih liječenja prvih maksilarnih pretkutnjaka s 3 korijenska kanala. Prvi slučaj je liječenje zbog protetske indikacije gdje su odmah uočena i tretirana sva 3 kanala, što je radiografski dokumentirano. Preostala 4 slučaja su retretmani jer prijašnja liječenja nisu bila uspješna zbog neprepoznavanja i netretiranja trećega kanala. Učinjeni retretmani radiografski su kontrolirani.Three-rooted maxillary first premolars do not occur usually, but their possibility always has to be considered. The buccal orifices of the root canals are not clearly visible. In spite of a good knowledge of tooth anatomy, clinical experience, and X-rays, the third canal is often overlooked. The incidence of maxillary first premolars with three roots, three canals and three foramina is about 4-6%. In this article 5 clinical endodontic cases of first maxillary premolars with three canals are presented. The first case presents endodontic treatment of the first right maxillary premolar for a prosthetic reason. All three canals were recognized and treated as documented by radiographs. The remaining cases were retreatment of the first maxillary premolars where third canals had remained unrecognized during previous endodontic procedures, resulting in failure of treatment. Retreatments were performed and results documented by radiographs

Patient’s Attitude to Rubber Dam Use

Svrha rada bila je procijeniti stajalište pacijenata prema uporabi koferdama i utvrditi utječu li neki klinički čimbenici na to njihovo stajalište. Pripremljen je upitnik s 10 pitanja koji su pacijenti anonimno ispunjavali nakon završena endodontskog postupka s koferdamom. Pacijenti su svrstani u dvije skupine: 1. skupina - terapeuti su bili studenti zadnje godine Stomatološkog fakulteta i 2. skupina - terapeuti su bili stomatolozi specijalisti i specijalizanti restaurativne stomatologije i endodoncije. Podatci su statistički obrađeni deskriptivnom statistikom i testovima Pearson hi-kvadrat i raščlamba varijance. Većina pacijenata (69,1%) u objema skupinama želi i dalje uporabu koferdama te smatra da je njegovo nošenje ugodno i udobno (58,2%). U 40,0% pacijenata stomatolog nije dao objašnjenje o razlozima uporabe koferdama, a kada je objašnjenje dano bilo je jasno svima osim dvoje. Vrijeme potrebno da se koferdam postavi bez pomoći asistentice u prosjeku je bilo oko 3 min, a trajanje endodontskoga liječenja pod koferdamom u prosjeku je bilo 68 min. Uspoređujući studentsko i doktorsko vrijeme za postavu koferdam i trajanje zahvata s koferdamom, studentima je u usporedbi sa specijalistima trebalo više vremena za jedno i drugo. Iz ovoga istraživanja može se zaključiti da: pacijenti nemaju odbojno mišljenje prema uporabi koferdama, postavljanje koferdama ne traje dugo, iskustvo terapeuta utječe na pacijentovo stajalište.The purpose of the study was to assess the patient’s attitude towards the use of a rubber dam and to determine whether any clinical factors influence it. After receiving endodontic treatment under a rubber dam, patients were asked to complete an anonymous questionnaire. They were divided into 2 groups: Group 1 - operators were final-year dental students at the School of Dental Medicine University of Zagreb and Group 2 - operators were (dentists) dental specialists and resident dentists at the Department of Restorative Dentistry and Endodontics, School of Dental Medicine University of Zagreb. The data were statistically analysed by descriptive statistics and Pearson chi square and variance analysis. The majority of the patients (69.1%) in both groups would prefer rubber dam use at their next appointment and consider it pleasant and comfortable to wear (58.2%). Dentists did not explain the reason for the use of the rubber dam to 40.0% of the patients, but when they did, all but two patients understood the explanation. The time required for placing the rubber dam without the assistant’s help was 3 minutes on average and the duration of the endodontic treatment under rubber dam was 69 minutes on average. When compared to the dental specialists students required more time to place the rubber dam and to perform endodontic treatment under it. From this study it can be concluded that patients do not have a negative attitude towards the use of a rubber dam, that the placement of a rubber dam does not take long and that operator’s experience influences the patient’s attitude

The Mutagenic Potential of Chloroform, Orange Oil, Eucalyptus Oil and Halothane by Salmonella/Microsome Assay

Svrha rada bila je ispitati mutagenu aktivnost četiriju komercijalno dostupnih otapala gutaperke Salmonella/mikrosomskim testom. Ispitana su bila otopala: kloroform, narančino ulje, eukaliptusovo ulje i halotan u količinama od 10 μl, 30 μl, 50 μl, 100 μl i 200 μl. Upotrijebljen je standardni Ames test inkorporacije na ploči pri čemu su rabljene bakterije Salmonella typhimurium soja TA 98 i TA 100 s metaboličkom aktivacijom enzimom S9. Rezultati istraživanja pokazuju citotoksičnu aktivnost eukaliptusova ulja u svim koncentracijama, narančina ulja u koncentracijama od 50 μl i većima. Kloroform je pokazao citotoksičnost u koncentracijama od 100 μl i 200 μl. Niti jedno otapalo gutaperke nije pokazala mutagenu aktivnost Ames testom u ispitivanim koncentracijama.The aim of this study was to examine mutagenic activity of four commercially available gutta-percha solvents by means of the Salmonella/ microsome assay. The examined solvents were: chloroform, orange oil, eucalyptus oil and halothane in amounts of 10 μl, 30 μl, 50 μl, 100 μl and 200 μl. Standard plate incorporation Ames test was preformed by using two tester strains of Salmonella typhimurium, TA 98 and TA 100, with metabolic activation of S9. The results showed toxicity of eucalyptus oil in all aliquots, orange oil in aliquots of 50 μl and above and chloroform in aliquots of 100 μl and 200 μl, but all four substances responded negative to the Ames test. These results indicate that the tested solvents do not possess mutagenic activity toward the Salmonella strains used

Remaining Filling on the Root Canal Walls after Retreatment with Three Gutta-percha Solvents

Svrha istraživanja bila je utvrditi količinu zaostale gutaperke i cementa na stijenkama korijenskoga kanala nakon uporabe triju različitih otapala gutaperke: eukaliptusova ulja, halotana i narančina ulja. Sedamdeset jednokorijenskih zuba je instrumentirano «step back» tehnikom te ispunjeno gutaperkom i Diaket cementom tehnikom hladne lateralne kondenzacije. Nakon 180 dana pohrane u fiziološkoj otopini uzorci su podijeljeni u tri skupine. Revizija je napravljena ručnim instrumentima s dodatkom otapala. Postupak je završen kada nije bilo tragova gutaperke i cementa na instrumentu ili na papirnatome štapiću. Zubi su raskoljeni te snimljeni kamerom montiranom na steromikroskop. Površina zaostale gutaperke i cementa izračunane su računalnim programom «ISSA». Najviše je punila zaostalo na stijenkama korijenskoga kanala nakon revizije s narančinim uljem (3,85 ±3,15 mm2), zatim s halotanom (3,72 ±2,52 mm2), a najbolji su rezultati postignuti s eukaliptusovim uljem (2,82 ±1,31 mm2), ali bez statistički znatne razlike.The aim of the investigation was to evaluate the amount of remaining gutta-percha and cement on dentine walls of the root canal after retreatment with three different gutta-percha solvents: eucalyptus oil, halothane and orange oil. Seventy one-rooted teeth were instrumented by “step-back” technique and filled with gutta-percha and Diaket cement using a cold lateral condensation technique. After 180 days storing in saline solution the samples were divided into three groups. Retreatment was done by hand instruments with the addition of solvent. The procedure was considered finished when there were not obvious traces of guttapercha and cement on the instrument or paper point. The teeth were split and photographed by camera mounted on a stereomicroscope. The area of remaining gutta-percha and cement was calculated by computer program “ISSA”. The greatest amount of remaining root canal filling was found after retreatment with orange oil (3.85 ±3.15 mm2), followed by halothane (3.72 ±2.52 mm2), and the best result was achieved with eucalyptus oil (2.82 ±1.31 mm2), but without statistical significance

A Comparison of Oral Status of the Fourth-Year Students of Various Colleges at the University of Zagreb

Svrha: Svrha istraživanja bila je usporediti oralni status studenata četvrte godine Stomatološkog fakulteta te studenata četvrte godine ostalih fakulteta Sveučilišta u Zagrebu. Ispitanici i postupci: Istraživanjem je bilo obuhvaćeno 78 studenata stomatologije i 78 njihovih kolega s ostalih fakulteta Sveučilišta u Zagrebu. Pregledi su obavljeni prema metodologiji i kriterijima SZO-a (WHO-a) stomatološkim zrcalom, a parodontološkom sondom Community periodontal index (CPI). Rezultati: Prosječna vrijednost KEP-indeksa svih ispitanika bila 7,97 (s.d.= 4,48), a bila je veća kod muškaraca negoli kod žena (p=0,043). Studenti stomatologije imali su prosječan KEP 6,96 (s.d.=4,82), a oni s ostalih fakulteta 8,97 (s.d.=3,88), sa statistički značajnom razlikom (p=0,005). Prosječan CPI statistički se značajno razlikovao (p=0.001) i kod studenata stomatologije je iznosio 1,91 (s.d.=2,40), a kod ostalih 2,99 (s.d.=2,23). Većina studenata ostalih fakulteta ( 66 %) treba, osim preventivnog tretmana, i konzervativno liječenje za razliku od studenata stomatologije od kojih 83 posto ne treba nikakvo liječenje ili treba samo preventivno. Zaključak: Premda je pojavnost karijesa, parodontnih bolesti i potreba za stomatološkim liječenjem niža kod studenata stomatologije, razmjerno visoka vrijednost KEP-a u objema skupinama ispitanika upućuje na nužnost boljeg preventivnog djelovanja u društvu. Zbog svijesti o oralnom zdravlju i preventivnim mjerama studenti stomatologije mogu biti pozitivan primjer kolegama s ostalih fakulteta.Objectives: To compare oral status of the fourth-year students of the School of Dental Medicine, and other fourth year students from the University of Zagreb. Materials and methods: Research included 78 dental students and 78 students of other colleges of the University of Zagreb. A standard dental check-up was performed following the WHO‑prescribed methodology and criteria, and by using a dental mirror and community periodontal index (CPI) probe. Results: Mean DMFT of all examined subjects was 7.97 (s.d. = 4.48), with a higher value for males than females (p =0.043). The dental students had a mean DMFT of 6.96 (s.d. =4.82) and the non-dental students group DMFT of 8.97 (s.d. =3.88). This difference was statistically significant (p =0.005). Average CPI indices difference of the examined groups (dental students – 1.91, s.d. =2.40; non-dental students – 2.99, s.d. =2.23) was also statistically significant (p=0.001). The majority of non-dental students (66%) needed, in addition to preventive measures, a conservative dental treatment, in contrast to the dental-students group, where 83% required only preventive or no dental treatment at all. Conclusions: Although the incidence of dental caries, periodontal diseases and treatment need is lower in dental students, the relatively high value of DMFT indices in both groups indicates the need for better preventive measures. Due to an inherent increased awareness of oral health and preventive measures, the dental students could set a good example to their fellowstudents of other colleges

Incidence of Dentinal Micro Cracks during Root Canal Preparation with Self Adjusting File, Reciproc Blue, and ProTaper Next

Introduction: Forces formed during root canal instrumentation could cause the crack formation in dentinal walls. Their propagation may result in vertical root fracture and eventually tooth loss. The aim of the study was to explore microcrack formation after root canal preparation with Self-adjusting File (SAF), Reciproc Blue (RB), and ProTaper Next (PTN) instruments on young premolars by means of micro-computed tomography. Methods and Materials: Forty-five upper premolars with two canals, were extracted due to orthodontic reasons from patients aged 16 to 20 years and stored for up to two months. The teeth were scanned with a micro-CT (Nikon XT H 225, Tring, UK) at structural resolution of 20.2 µm and randomly divided into three groups: SAF, RB, and PTN. Specimens were instrumented and irrigation was performed with 12 mL of 2.5% sodium hypochlorite (NaOCl) and 4 mL of 17% ethylenediaminetetraacetic acid (EDTA) per root canal. Subsequently, the specimens were scanned under the same conditions as before, in wet condition and 24 h after drying. The presence of microcracks in dentinal walls was evaluated using the image-processing software Volume Graphics VGStudio Max 3. Results: No dentinal defect was found in any evaluated specimen, neither in pre-nor post-operative scans in wet and dry condition. Conclusion: Under the circumstances of this in vitro study instruments with improved design and metallurgy do not cause dentinal microcracks in young premolar teeth.Keywords: Dentin; Micro-computed Tomography; Nickel-titanium; Root Canal Preparatio

The Loss of Hard Tissue at the Tooth Cervix

Zubni vrat posebno je osjetljivo područje gdje se očituju razni patogeni procesi. Gubitak tvrdih tkiva zubnoga vrata dijeli se prema etiologiji na: karijes, eroziju, abraziju i abfrakciju. U radu je prikazan način nastanka svake od tih lezija, njihov klinički izgled i terapijski pristup. Naglašena je važnost preventivnoga djelovanja stomatologa sa svrhom da se smanji čestoča cervikalnih lezija.On the cervical part of the tooth various pathological processes can be seen. Loss of hard tooth structure in the tooth cervix can be caused by caries, erosion, abrasion and abfraction. In this paper the mechanism of the development, clinical appearance and therapeutic approach for each of these lesions is discussed. The role of the dentist is emphasised in the prevention of the incidence of cervical lesions