Vol 8, No 1 (2011)
Proceeding Abstracts
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Objective: Punica granatum has been used for many years in folk medicine due to several
purposes. The aim of the present study was to evaluate the effect of methanolic extract of
Punica granatum peel (MEPGP) against Streptococcus mutans, Staphylococcus aureus,
Streptococcus salivarius, Streptococcus sanguinis, Staphylococcus epidermidis, Actynomyces
viscosus, Lactobacillus acidophilus and Candida albicans.
Materials and Methods: In this in vitro study, the mentioned oral organisms were cultured
in blood agar and mueller-hinton media and then paper disks containing MEPGP at
concentrations of 4 mg/ml, 8 mg/ml and 12 mg/ml were inserted on medias. The antimicrobial
activity was evaluated by agar disk diffusion method. The effects of three different
concentrations of MEPGP against microorganisms were compared using one-way
ANOVA and Tukey tests.
Results: All concentrations of MEPGP had antibacterial activity against S. aureus and S.
epidermidis. Only at concentration of 8 mg/ml and 12 mg/ml MEPGP was effective
against L. acidophilus, S. mutans and S. salivarius. Furthermore; no concentrations of
MEPGP inhibited A. viscosus and C. albicans.
Conclusion: This study suggests that MEPGP might be used as an antibacterial agent in
controlling oral infections. -
Objective: Implants are being used in orthodontics as a reliable mode of anchorage. Among other factors, the cortical bone thickness plays a major role in determining the stability of these implants. The objective of this study was to study the relationship of various
arch forms and the cortical bone thickness and to determine if the cortical bone thickness varies between various arch forms. This would help to determine the ideal length of an implant for a particular arch form.
Materials and Methods: A cross sectional tomograph was obtained from 30 patients. Based on arch forms the patients' tomographs were equally divided into three basic square, tapered and ovoid categories, each consisting of 10 patients. Consequently, their buccal and lingual cortical plate thicknesses were measured.
Results: The results showed that there was a statistically significant difference between the three arch forms, in which the square arch form had the greatest cortical bone thickness among the three arch forms.
Conclusion: Patients having a tapered arch form may require implants with greater length than patients having a square or an ovoid arch form. Since the availability of the cortical bone in square arch patients is greater, there is more stability for the implants in these cases;
therefore, implants with a shorter length may be used in these cases. -
Objective: Predoctoral dental implant education is included in dental school teaching curricula in most of the developed and some developing countries; however, it was not introduced into undergraduate curriculum of some countries and Iranian dental schools. Our purpose was to investigate the status of the predoctoral dental implant education of dental schools in the world.
Materials and Methods: One hundred-thirty five dental schools were randomly selected representing 62 countries divided into two regions. The first region included North America and Europe, and the second region comprised of Asia, South America and Africa. A questionnaire including onset year, lecture hours, lectures available on the internet, required textbooks, department jurisdictions, the year of dental school the course was offered, clinical and laboratory courses, implant systems used surgically and in restorative phase, and type of restorations treated by predoctoral students was mailed electronically to the predoctoral implant dentistry directors.
Results: Ninety-two (68%) schools responded; of which 79 (86%) incorporated implant dentistry in their predoctoral teaching curricula, 39 (49%) offered surgical and prosthodontics courses in which students mainly observe. Of these 39 dental schools,28 (71%) and 11 (29%) dental schools are from the first and second region, respectively.
Conclusion: A large percentage of responding schools included implant education in the predoctoral dental curriculum. Onset year of course, topics included in lecture series, lecture hours, faculty to student ratio and practical course vary among schools. Fifty percent
of responding dental schools including Iranian dental schools do not have curriculum guidelines for predoctoral implant dentistry. -
Objective: Application of chemical solvents especially in problematic canals is usually a
part of the retreatment process.This study was performed to compare the solubility of Gutta-
Percha and Resilon in chloroform and to find the effect of sample thickness as well as
the time of shaking on their solubility.
Materials and Methods: Specific weight of Resilon and gutta-percha was placed in a
sample tube and after adding 1.0 ml of chloroform at 37ºC, the tubes were capped and
shaked for 1, 3 and 5 minutes. The amount of non dissolved material was determined by
reweighting of each sample and the percent of solubility was assessed according to the exact
weight loss of the samples. The procedure was repeated three times for a given thickness
and time of shaking. The difference in the solubility of Gutta-Percha and Resilon as
well as the effect of sample thickness and time of shaking on solubility were assessed by
repeated measurement ANOVA (p<0.05).
Results: Resilon has significantly higher solubility than Gutta-Percha in chloroform
(p<0.05). Resilon as well as Gutta-Percha Solubility are increased significantly over the
time .The amount of solubility is not affected by sample thickness.
Conclusion: Comparison of Resilon and Gutta-Percha solubility in chloroform shows
that one of the advantages for Resilon could be the chance for using possible safer organic
solvents during retreatment. -
Objective: To measure the long-term linear hygroscopic expansion (LHE) of several materials
using bulked and layered techniques.
Materials and Methods: Seven materials were used; Fuji Cap II, Fuji II LC, Photac-Fil
Aplicap, Vitremer, Dyract, Tetric and Z100. Ten specimens (6×4 mm) were made for each
material using layered and bulked techniques (each group comprises five specimens). The
specimens were stored in distilled water at 37°C. The length of each specimen was measured
immediately after preparation, 24 hours, one week, one month, three months, six
months, nine months and one year. This was used to calculate the percentage change in the
length of materials. The mean LHE and standard deviation were calculated. Repeated
measure analysis and paired sample t-test were used.
Results: The type of material and time had a significant effect on LHE. Fuji Cap II and
Fuji II LC exhibited no significant changes after one-year and one month, respectively.
However, layered specimens of Photac-Fil Aplicap and Tetric showed constant expansion
until six month, whereas bulked specimens reached the constant length at three months.
Constant expansion was obtained for layered and bulked specimens of Dyract and Z100 at
six month. Layered specimens of Vitremer showed no significant differences except between
24 hours and one year measurements. But in bulked specimens, the results at nine
months and one year were significantly different from those obtained at three months and
before.
Conclusion: Fuji II showed no significant LHE and resin-modified glass ionomer cements
(RMGICs) exhibited the highest LHE. Dyract maintained an intermediate LHE in comparison
with RMGIC and composite resin. -
Objectives: This study evaluated the effect of surface polishing on mercury release from
dental amalgam after treatment with 16% carbamide peroxide gel.
Materials and Methods: Ninety-six samples from two different amalgam brands were
prepared in truncated cone-shaped PVC polymer molds with an external surface area of
195 mm². Half of the specimens were polished with green and red rubber, a brush and tin
oxide paste at low speed. Samples were treated with 16% carbamide peroxide gel in
tubes containing 3 mL of carbamide peroxide gel and 0.1 mL of distilled water for 14 and
28 hours. Subsequently, carbamide peroxide gel on the sample surfaces was rinsed away
with 7.0 mL of distilled water until the volume of each tube increased to 10 mL. The
mercury level of each solution was measured using the VAV-440 mercury analyzer system.
Considering the surface area of each amalgam disc, mercury amounts were calculated
in μg ⁄mm². Data were analyzed using two-way ANOVA.
Results: There were significant differences between the mean levels of mercury release
from polished vs. unpolished amalgam surfaces after treatment with 16% carbamide peroxide.
Increasing the storage time from 14 to 28 hours did not result in significant
changes in the amount of mercury release. There was no significant interaction effect
between amalgam surface polish and storage time statistically.
Conclusion: Polished amalgam restorations release less mercury after treatment with
carbamide peroxide bleaching gel in comparison with unpolished amalgam restorations. -
The improvement in survival and local control measures in children with neoplasm in the
head and neck region may lead to increased iatrogenic adverse effects of treatment. The
aim of this study was to report a new case of the long-term effects of chemoradiotherapy
on oral health and dental development in a patient treated for Hodgkin's disease at an early
age. In this case report, a 26-year-old female is presented, who at the age of 5 years received
chemotherapy and radiotherapy for Hodgkin's disease in the neck region. The patient
consulted the Department of Oral Medicine because of dental changes and tooth loss
despite adequate dental care and oral hygiene. Clinical examination revealed loose teeth
and inflamed gingiva of the mandible, x-ray showed premature root resorption, V-shaped
and shortened roots and alveolar bone loss. After examination, the patient was referred for
extracting the mandibular teeth and then wassent to the prosthetics department. Therefore,
in order to decrease dental treatment sequelae in patients who have had cured malignant
disease, these cases should have life-long dental care and follow-up. -
Acute Lymphoblastic Leukemia (ALL) is the most prevalent hematological malignant tumor
during childhood. Unilateral infiltration into the gums is less prevalent and more often
observed in the AML type.
A 12-year-old girl with symptoms of pain and swelling in the buccal vestibule and also at
the posterior part of the right palate of the maxilla was referred to a private dental office.
The patient had been inflicted by ALL and had undergone complete chemotherapy. A
week prior to her admittance into the hospital, the workup of the patient's blood revealed
her recovery. The clinical and radiographic evidence did not show any dental problems.
The histological examinations on the patient's jaw revealed the correct diagnosis of ALL
and the patient underwent chemotherapy for the second time.
This case has been reported to point out that intraoral unilateral swelling of the upper jaw
may be propounded as the primary diagnostic symptom of ALL.
