Silvana Jukić

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.

Coronal Microleakage of Two Root-end Filling Materials Using a Polymicrobial Marker

The purpose of this study was to evaluate polymicrobial coronal leakage of mineral trioxide aggregate (MTA) and amalgam. There were 108 single-rooted teeth randomly divided into 3 groups of 32 teeth each and positive and negative control groups of 6 teeth and obturated with gutta percha and either Diaket (3M/ESPE, Seefeld, Germany), AH Plus (Dentsply, De Trey, Konstanz, Germany), or Ketac Endo (3M/ESPE). These groups were further divided into 2 subgroups of 16 teeth in which root ends were resected and obturated with either MTA or zinc-free amalgam. The samples have been incorporated in a dual-chamber leakage model with a polymicrobial marker of five facultative anaerobes on the coronal part. Leakage was observing during a period of 90 days. The least leakage was found in a combination of Diaket and MTA (76.9 +/-14.8 days) followed by AH Plus and MTA (66.1 +/- 18.7), Diaket and amalgam (60.0 +/- 23.1), AH Plus and amalgam (56.9 +/- 22.1), and Ketac Endo and MTA (42.1 +/- 17.8), whereas the greatest leakage was observed in the Ketac Endo and amalgam group (40.0 +/- 17.24). Samples filled with MTA showed significantly better sealing than samples filled with amalgam (p < 0.05).

The Mutagenic Potential of AH+ and AH26 by Salmonella/Microsome Assay

The aim of this study was to examine the mutagenic potential of canal sealers AH+ and AH26 by Salmonella/microsome assay. The materials were tested immediately after mixing, 1 hr and 1 month later, respectively. The dimethyl sulfoxide extracts of sealers in amounts of 3.0, 1.5, and 0.75 microliters/plate were used. The plated bacterial strains of Salmonella were TA 98 and TA 100. The results showed that AH+ is mutagenic toward strain TA 100 1 hr after mixing. One month after mixing, mutagenic activity was expressed only in TA 98. Paste A showed strong mutagenicity toward TA 100. AH26 was more mutagenic to the TA 100 immediately after mixing, 1 hr later, and 1 month after it was polymerized. Also it was mutagenic toward TA 98 in the polymerized condition. Further examinations should be conducted to establish a definitive conclusion about mutagenic potential for these two endodontic materials.

Učestalost nalaza bakterijskog sadržaja u perzistentnim periapikalnim lezijama

Objectives To determine the percentage of persistant apical lesions positive for bacterial nucleic acids, to detect microorganisms difficult to cultivate in persistant apical lesions by PCR and relate them to endodontic failure, clinical symptoms and diabetes mellitus. Materials and methods The samples of persistent apical lesions were collected during apicoectomy. Bacterial ubiquitous primer 16S rRNA was used to detect 16S ribosomal RNA in 36 samples. A species–specific PCR was performed with primers targeted to the bacterial 16S rRNA genes of Prevotella Nigrescens, Pseudoramibacter alactolyticus, and Propionobacterium propionicum. Results Six samples (16.67%) were positive for bacterial ribosomal RNA. Pseudoramibacter alactolyticus was detected in three samples. Propionibacterium propionicum and Prevotella nigrescens were detected in one sample each. The prevalence of infection of such lesions with P. intermedia, P. propionicum and P. alactolyticus is low. Conslusion The study we conducted gave insufficient data about extraradicular infection and its connection with diabetes mellitus and clinical symptoms. Conclusions Apical lesions persisting after endodontic treatment could harbor microorganisms other than Actinomyces and Propionicum species.

Radiomorphometric indices of mandibular bones in an 18th century population.

OBJECTIVE To estimate four radiomorphometric indices of mandibular bones in an 18th century population sample, and possibly associate the findings with bone mass loss related to sex, age, nutritional habits and pathologies reflecting on the bone. DESIGN Thirty-six sculls (31 males, 5 females), recovered from the crypt of Požega Cathedral in Croatia were analyzed. Age estimation was based on tooth wear, and Eichner class was determined according to the number of occlusal supporting zones. The parameters in recording analogue orthopantomographs were set to constant current of 16 mA, exposure time of 14.1s, and voltage between 62-78 kV. Films were processed in an automatic dark chamber processor for 12 min, and digitized at 8-bit, 300 dpi. The thickness of the mandibular cortex was assessed below the mental foramen (MI), at antegonion (AI), at gonion (GI). Qualitative mandibular cortical index (MCI) was assessed. RESULTS Average values of MI, AI and GI were 3.97 ± 0.94 mm, 2.98 ± 0.56 mm, and 1.99 ± 0.55 mm, respectively. Statistically significant differences between males and females were found for AI right (p=0.014), GI left (p=0.010) and GI average (p=0.006), and were in all cases higher in males. There were no statistically significant differences between age groups for either index (p>0.05). Considering Eichner classification the differences were not significant for MI (p=0.422), AI (p=0.516), and GI (p=0.443), but in Eichner classes II, MCI was significantly higher (p=0.02). CONCLUSION The obtained data does not suggest generalized malnutrition or calcium, phosphorus and vitamin D deprivation in the historic population studied.