Vol 6, No 2 (2009)
Proceeding Abstracts
-
Objective:
The aim of the present study was to compare the performance of laser fluorescence
(LF) method with other conventional diagnostic techniques in detection of small
occlusal caries in permanent teeth.
Materials and Methods:
Prior to this in vitro diagnostic study, a pilot study assessed intra-examiner reliability and reproducibility. The occlusal surfaces of 90 extracted human
premolars were examined with four diagnostic methods: probing, visual inspection, bitewing
(BW) radiographs, and LF. The teeth were then sectioned for the purpose of histological
examination. The data were analyzed using SPSS 15 software, and sensitivity,
specificity and other diagnostic criteria of the techniques were calculated.
Results:
The intra-examiner reproducibility for probing and also radiographic techniqueswas 100%. The corresponded figure for LF (88%) was more than visual inspection (82%).
The highest level of validity of the examiner turned out to be in probing technique
(76.9%). Sensitivity of visual inspection, probing, and LF methods was 54.5% and that of
BW radiography was 27.5%. Specificity and efficiency of LF method were 84.8% and
81.1%, respectively. Probing and visual inspection showed the highest specificity (97.5%
and 94.9, respectively) and efficiency (92.2% and 90%, respectively) among the methods.
Conclusion:
Specificity and efficiency of LF method were lower compared to those ofother methods. Among all the investigated methods, the most efficient methods in the diagnosis
of small occlusal caries in permanent teeth were probing and visual inspection,
respectively.
-
Objective:
Evidence shows periodontally infected patients may be at a higher risk of thrombotic accidents and adverse pregnancy outcomes, via induced systemic inflammatory mediators' production. Some authors have concluded that increase in systemic inflammatory markers occurs together with increase in serum levels of auto antibodies including anti-cardiolipin antibody (ACLA). The aim of the present study was to compare the serum ACLA level between patients with chronic periodontitis (CP) and periodontally healthy controls.
Materials and Methods:
Fifty-one patients with moderate and advanced CP (test group) and 49 periodontally healthy people (control group) were included in the study. Clinical parameters including PI, GBI, PPD and CAL were measured. Serum ACLA level of all cases was measured using ELISA method. The data were analyzed with Student t-test and Pearson's correlation.
Results:
A significant difference existed in serum ACLA level between test and control groups (P=0.001). All cases in both test and control groups, however, showed a normal range of serum ACLA level. A positive correlation also existed between serum ACLA level and periodontal parameters including CAL, PPD, GBI and PI (P<0.001, P<.001, P=0.001 and P=0.002, respectively). In addition, a moderately positive correlation (P=0.003) between age and ACLA level was found.
Conclusion:
An increased serum ACLA level might be associated with chronic periodontitis.
-
Objective:
Assessment of subgingival human cytomegalovirus (HCMV) and Epstein Barr virus (EBV-1) in subjects with aggressive periodontitis.
Materials and Methods:
Samples were obtained from plaques formed in subgingival regions of 26 aggressive periodontitis patients. All specimens were submitted to polymerase chain reaction in order to detect HCMV and EBV-1.Results:
HCMV and EBV-1 were observed in 27% and 25% of the participants respectively. Coinfection with both viruses was found in 52% of the patients.Conclusion:
Within the limitations of the present study, it can be suggested that HCMV and EBV-1 in subgingival plaques may be associated with aggressive periodontitis. Additionally, concomitant occurrence of these viruses may negatively affect the wellbeing of periodontal tissues -
Objective:
To assess the stability changes as a reflection of early healing around roughened- surface implants in human by resonance frequency analysis (RFA).
Materials and Methods:
One hundred and fifty one ITI SLA implants were placed in either maxilla or mandible of 68 patients. Bone type was classified into 4 groups according to Lekholm and Zarb index. RFA was used for direct implant stability measurement on the day of implant placement, and at 14, 30 and 60 days after placement. Student t-test and ANOVA served for statistical analysis.Results:
No early failure occurred. The highest and lowest primary stability was measured in type 1 and type 4 bone, respectively. Implant stability increased over time in types 3 and 4 bone but continuously decreased in type 1 bone during the first 60 days of healing. In type 2 a small decrease in stability was observed until 30 days, and after that the stability increased. The difference between implant stability in type 2 and type 4 bone at each time point was highly significant (P<0.001). Implant stability did not change significantly during the 60-day period in type 2 bone (P>0.05). The effect of implant length and diameter on stability at different times was tested with mixed model ANOVA, and no significant difference among groups was observed (P>0.05)Conclusion:
The present study demonstrated that the pattern of stability changes was different among various bone types. With regard to primary stability and pattern of stability changes in types 2 and 3 bone, immediate and early loading protocols can be recommended in these two bone types, respectively. -
Objective:
The present in vitro study was undertaken to compare the effects of hydrogel and solution forms of sodium ascorbate on microleakage of composite restorations subsequent to a non-vital bleaching procedure with 10% carbamide peroxide.
Materials and Methods:
Forty-eight sound extracted human maxillary incisors were obtained. Following root canal therapy, the teeth were randomly divided into an unbleached control group (group 1) and three experimental groups in which bleaching was performed (12 teeth in each group). Non-vital bleaching with 10% carbamide peroxide was carried out for periods of 8 hours a day for one week. In group 2, the specimens were restored immediately after bleaching. Group 3 specimens were treated with sodium ascorbate solution, whereas in group 4 specimens, sodium ascorbate hydrogel was used before placement of composite restorations. Following thermocycling, the specimens were subjected to dye leakage (methylene blue) test. Statistical analysis was carried out using Kruskal- Wallis and Dunn multiple comparison tests at a significance level of P<0.05.Results:
Significant differences existed in microleakage scores among the four groups (P<0.0005). Pairwise comparison of groups with Dunn test revealed that higher microleakage scores in group 2 compared to each of the other three groups was statistically significant (P<0.001) while the differences between other groups were not statistically significant (P>0.05).Conclusion:
Ten percent carbamide peroxide significantly increases microleakage of composite restorations when bonding is performed immediately following non-vital bleaching. Compromised sealing ability of composite restorations is reversed with application of both forms (hydrogel and solution) of sodium ascorbate, as an anti-oxidant. -
-
Objective:
The purpose of the study was to evaluate the influence of adding nanofiller particles to a dentin bonding agent on resin-dentin bond strength.
Materials and Methods:
Fifty-four human intact premolar teeth were divided in to 6 groups of nine. The teeth were ground on occlusal surfaces and polished with 320 and then 600 grit silicon carbide papers. An experimental bonding system based on acetone/alcohol solvent was provided with filler contents of 0.0, 0.5, 1.0, 2.5, 5.0, and 10.0 weight percent fumed silica nanofiller. After dentin surface etching, rinsing and blot drying, the experimental bonding agents were applied to dentin surface. A composite resin was, then, bonded to the dentin on the bonding agent. The specimens were thermocycled for 500 cycles and sectioned in stick form. After two week of storage in distilled water, resin-dentin microtensile bond strength of the specimens was measured. Data were analyzed by one way ANOVA and DunnettT3 tests.Results:
Bond strength to dentin was significantly affected by the filler level. Minimum and maximum resin-microtensile bond strength was in the experimental bonding agent with no filler (5.88 MPa) and with filler level of 1.0 weight percent (15.15 MPa), respectively and decreased with the increase of filler content down to 8.95 MPa for the filler level of 10.0 weight percent.Conclusion:
Filler content seems to be one of the important factors influencing the bond strength of dental adhesives. Maximum dentin bond strength was obtained with 1% silanized nanofiller silica added to experimental adhesive system. -
Langerhans cell histiocytosis is a relatively rare unique disease process characterized by an abnormal proliferation of immature dendritic cells usually affecting children and young adults. Jaws are involved in less than 10% of children with the disease while mandibular involvement in young children is uncommon and bilateral affection is very rare. The purpose of this report is to describe a unique and very rare case of simultaneous and bilateral occurrence of Langerhans cell histiocytosis in both the jaws of a four-year-old boy.
