MUSTANSIRIA DENTAL JOURNAL

Abstract
Background: This study investigated the influence of composite type and shade on depth of cure of light- activated composites.
Materials and methods: This study investigated the depth of cure of two composite materials using two different shades. Parameters included two shades (A1 and C3) of two different light-activated composites(Helio Progress and King Dental) cured for 40 seconds.
Results: Statistical analysis of the data by using the one-way analysis of variance revealed that, both composite type and shade significantly affect composite depth of cure.
Conclusion: This study indicated that, Although, both composite type and shade were significantly affect depth of cure but the effect of composite type on composite depth of cure is much more than that of composite shade.

The purpose of this in-vitro study is to evaluate and compare the fracture
resistance of endodontically treated teeth restored using cast posts cemented with
different types of cement. Thirty intact human maxillary central incisors were selected
for this study. The crowns were removed and endodontic therapy were done on the
roots, which were then prepared to receive cast posts, after their fabrication, the cast posts were cemented with zinc phosphate cement (group I), resin modified glass ionomer cement (group II),and resin cement (group III). The samples were subjected to compressive fracturing loads by a Zwick testing machine at a cross head speed of 5mm/min., with an angle of 45º to the long axis of the tooth. The results showed that the posts cemented with resin cement exhibited the highest mean failure load followed by posts cemented with resin modified glass ionomer cement , while posts cemented with zinc phosphate cement exhibited the lowest mean failure load.

Aim: The present study compares the accuracy of conventional and digital
radiographic system in the determination of apical fitness in endodontic therapy.
Method: Thirty three root canals of first upper and lower molar teeth were used in
this study; a K-file was inserted into the canal until its tip was fit snuggly one
millimeter shorter than the apex. Each tooth was radiographed twice with two
different radiographic systems; conventional & digital systems. The right-angle
paralleling technique with film holders was used in both systems. The distance
between the file tip and the center of radiographical apex from both imaging systems
was measured by two examiners and the mean of each two measurements was
recorded, the data was collected and analyzed statistically by paired t- test.
Results: The mean value of radiographic length reveals that there is a very small
difference between the measurements of conventional radiographic system(0.8727mm) and those measurements of digital radiographic system (0.8367mm) when compared with the real length measurements (1mm). Paired t-test shows that there is no significant difference (p < 0.05) was founded between the real measurements and the radiographic measurements are taken from both conventional and digital systems. In conclusion both the conventional and digital imaging systems can be used accurately for working length determination in an endodontic therapy.

on the same light-cured microfilled composite resin (Helioprogress, vivadent,
Germany). 40 specimens were prepared, stored in deionized distilled water at 37°C
for 24 hours and divided into 4 groups.
Group 1: The repair procedure done once.
Group 2: The repair procedure done twice.
Group 3: The repair procedure done for three times.
Group 4: The repair procedure done for four times.
All the specimens stored in deionized distilled water at 37°C for 24 hours before
testing. A universal zwick testing machine with a special designed chisel was used to
evaluate the shear bond strength of the repaired composite resin. The results showed
reduction in mean shear bond strength value from group 1 to group 4, furthermore a
significant difference was found between group 1 Vs group 3 and group 1 Vs group 4.

Background: Clinical preventive procedures must be done after careful assessment;
one of the major risk factor is the occlusal morphology of the posterior teeth. These
caries free fissures must be sealed. This in vitro study evaluated the microleakage of
two types of sealant materials (unfilled resin and flowable composite) on enamel
surfaces prepared using two methods (acid etching with enameloplasty and acid
etching alone).
Material and methods: Thirty two extracted human third molar were selected and
randomly assigned in to 4 groups of eight teeth each; group A, the occlusal surfaces of
teeth were acid etched ,then sealed with concise white sealant; group B, they were
acid etched then sealed with wave mv flowable composite ;group C, they were
prepared with bur ,acid etched ,then sealed with concise white sealant ;group D, they
were prepared by bur, acid etched, then sealed with wave mv flowable composite. The
sealed surfaces were stored for seven days in distilled water, then specimens were
thermocycled 500 cycles, immersed 24 hours in a 2% buffered methylene blue dye,
then sectioned and analyzed for leakage under a stereo microscope. Chi-square test
was performed to test the differences of leakage among the four groups.
Results: The results showed that there was no significant difference (p>0.05) in
microleakage for the same material with and without bur preparation. Concise white
sealant produced significantly (p<0.05) less microlaekage than wave flowable
composite.
Conclusion: under the conditions of the present study, bur preparation
(enameloplasty) followed by acid etching produces no less microlaekage than did acid
etching alone. Concise white sealant (unfilled resin) demonstrated less amount ofmicrolaekage when compared to wave mv flowable composite.

Magnesium is one of the major cations in plant and animal tissues and is an essential constituent of the bone and tissue, as well as the body fluids. Concentrations of most electrolytes in saliva are subjected to considerable alteration. The aim of this
study was to investigate the salivary magnesium in relation to dental caries. A sample
of 46 adults was involved with age range of 20-45 years. Samples of stimulated saliva
were collected and prepared to be analyzed for magnesium estimation using atomic
absorption spectrophotometer. Clinical examination was done for dental caries using
WHO criteria. The salivary magnesium concentration was 0.38mg/dl. Neither the sex, nor the age influenced the concentration of magnesium in supernatant stimulated saliva. Negative correlations were found between salivary magnesium and age, salivary flow rate, while, a positive correlation was recorded with dental caries. All these associations were not proved to be significant (P<0.05). Further investigation should be done on whole saliva to clarify the association between magnesium and dental caries. The magnesium relation with the other elements must be considered.

Cephalometric radiographs were taken for (48) subjects with class I occlusion ; (25) females and (23) males , which selected on the standarization of the radiographs.
Sample ages range 8-10 years . cephlometric tracing are carried out using the same points, lines, angles and axis of Rickett's analysis.
On comparing the results of this research which is carried out on Iraqi sample with Rickett’s analysis on Caucasian people of the same age appears that there are differences in most of these measurements and this due to racial factors and ethnic variations which play a great role in differences between each ethnic group .
The results of Iraqi measurements (mean values ) as fallows:-
facial axis (Y-axis) =91.3°; facial depth angle =81.2° ; Frankfort-mandibular plane angle=30°; convexity of point A (mm)=2.7mm; lower incisor to A-pog =1.8mm;angle =26.1° and finally ANS-Xi-Pm angle (lower facial height) = 45.8°.

Background: This study is to compare between Amalgam and Mineral Trioxide
Aggregate as retrograde filling in the healing process of periapical surgery by clinical
and radiographical evaluation.
Material and method: A follow up study of twenty patients, eleven were
females, nine were males, of average age (12-36) years old, with forty upper central
incisors involved with chronic periapical lesions, each patient has two central incisors
with two separated periapical lesions, the right side was apically filled with Zinc free
Amalgam and named as a control group (Group A), and the left side was filled with
MTA as a study group (Group B). All patients were recalled within three months and
six months, and subjected to clinical and radiographical examinations, to evaluate the
healing process of both groups.
Results: Clinically the study shows three failure cases (7.5%), one case (2.5%)
was objectively failure which shows sinus formation in Amalgam group and two
cases (5%) were subjectively failure, which shows pain and tenderness, one case in
each group. Radiographically, the study reported a remarkable bone formation 27
cases (67.5%), fifteen cases in MTA group and twelve cases in amalgam group after
six months. While 10 cases (25%), showed delayed bone formation, four cases were
in MTA group and six cases were in Amalgam group, and three cases (7.5%) were
showed enlargement in the size of radiolucency, one case in MTA group and two
cases in Amalgam group. According to the follow up during the six months, the MTA
group showed higher successful rate than Amalgam group, and the failure cases in
group A was 10% and 5% in group B.
Conclusions: The study shows that the best results are in those patients who have
failure in root canal filling, and in those patients who did not have labial sinus formation and labial cortical bone perforation. MTA group, shows decreased in (Mesio-Distal, Superio-Inferior dimensions and cavity surface area), faster than the Amalgam group.

Abstract
Thorough clinical and radiographic examination is necessary to detect, evaluate
and diagnose periodontal disease. The aim of present study is to evaluate interdental
bone loss in patients with chronic adult periodontitis radiographically. One hundred eighty sites (for maxillary anterior teeth only) were examined for type and severity of alveolar bone loss. The results reveal that 80% of all examined sites had different severity of bone loss. Mild bone loss was more frequent than Moderate or Severe and
horizontal more than vertical or angular bone loss. Interdental bone between central and lateral incisors was the most affected site in this study.

This Study represents an attempt to investigate histologically the effect of metallic
mercury vapor on the developing rat teeth after inhalation by pregnant rats .
In this study albino – wistar rats were used and divided into control and
experimental groups.
The control group consisted of 8 pregnant rats, and the experimental group
consisted of 12 pregnant rats. Then 20 born rats from the control group and 20 born
rats from the experimental group were selected to be sacrificed at the ages of (3&13)
days.
The specimens were prepared for processing and staining with haematoxylin and eosin, and examined under light microscope.
Results showed no histological abnormalities in the dental tissue of the
experimental group when compared to that of the control group .
This Study represents an attempt to investigate histologically the effect of metallic mercury vapor on the developing rat teeth after inhalation by pregnant rats .
In this study albino – wistar rats were used and divided into control and
experimental groups.
The control group consisted of 8 pregnant rats, and the experimental group
consisted of 12 pregnant rats. Then 20 born rats from the control group and 20 born rats from the experimental group were selected to be sacrificed at the ages of (3&13) days.
The specimens were prepared for processing and staining with haematoxylin and eosin, and examined under light microscope.
Results showed no histological abnormalities in the dental tissue of the
experimental group when compared to that of the control group .

Background: Denture cleaner solutions are used extensively for the cleaning of
prosthesis both plastic and metallic component .The chemical composition of cleaner
solution are virtually important in defining their adverse effect on properties of acrylic
part of prosthesis
Aims of the study The present study carried out to study the effect of some
cleaning solution on tensile strength and indentation hardness of both types of acrylic
resin (hot and cold cured) and compare the effect on different types of denture
materials.
Materials and methods: Specimens of hot and cold cured acrylic resin were
prepared according to ADA specification for both indentation hardness and tensile
strength test. The specimen were immersed in distilled water for seven days then were
left in containers containing one of the following denture cleaners, Staradent 1%H202,
5%HCL& vinegar solution. Each container contained five specimens of either heat
cure or cold cure with one type of denture cleaners and they were left for seven days.
Specimens were then tested for indentation hardness and tensile strength test.
Results: The results showed that Vinegar solution has an deleterious effect on tensile strength and indentation surface hardness of hot cured acrylic resin as compared with control while for cold cure all specimens affected by all cleaning solutions.

The present study was performed to evaluate the effectiveness of newly designed
motor-driven fiberglass burs in root planing and compare it to manual instrumentation
using universal curette. Twelve patients complaining from periodontitis with deep
periodontal pockets were involved in this study. A total number of 139 pocket sites
received root planing by motor-driven fiberglass burs and 131 pocket sites were
planed manually by curette.
The root planing procedure was opened type; it was performed by modified
widman flap operation. The clinical parameters that were used in this study are
(plaque index, bleeding on probing, probing pocket depth and relative attachment level). They were recorded in 4 periodic visits 2 of them before treatment and 2 after treatment to assess the improvement and to make a comparison between the two methods of treatment.
The results revealed that there was a significant improvement in all of the clinical parameters after treatment with fiberglass burs.
Also the results showed that that there was no significant difference between the improvement that was implemented by the two methods of treatment.