MUSTANSIRIA DENTAL JOURNAL

Abstract
widespread use of rotary Nickel-Titanium systems has caused manufacturers to
produce gutta-percha cones that match the taper of the canals prepared with these
systems. The aim of this study was to use electrochemical method to compare the
apical sealing ability of taper single-cone, Thermafil obturation in canals prepared
with ProTaper and ProFile instruments. Forty extracted human mandibular premolar
were divided into 2 groups. All canals in group (A) prepared with ProFile, while all canals in group (B) prepared with ProTaper. Each group subdivided into two subgroup according to the method of obturation, (Thermafil and matched taper- single cone).The apical leakage in these groups was evaluated using an electrochemical method. T-test showed a non significant difference between Thermafil and matched taper-single cone obturation technique in the same group. A significant difference was found between ProTaper and ProFile group in both obturation techniques.

This study was done to assess bond strength of Polycarboxylate cement reinforced by different amount of Hydroxyapatite. In this study a hydroxyapatite materials were added to Polycarboxylate cement at different ratios;10%, 15%, 20%, 25% and 30% ( by weight ) and the bond strength was detected by construction a cylinders from these mixed materials, constructed on exposed dentine of human extracted premolar teeth and by Zwick’s universal testing machine the bond strength were detected for these mixed materials. Results showed that the Polycarboxylate reinforced by hydroxyapatite has higher bond strength than conventional Polycarboxylate cement and the hydroxyapatite powder to Polycarboxylate cement powder ratio by weight best to be 20%. The addition of hydroxyapatite to conventional Polycarboxylate cement increased its bond strength to dentine.

Abstract
in vitro study to evaluate the effect of an at-home bleaching product on the
surface hardness of three composite restorative materials.
The aim of this study was to evaluate the effect of at-home bleaching on the
surface hardness of the tooth colored restorative materials.
Thirty specimens were prepared; 10 specimens of each material 5 specimens
control of each group. All specimens were stored in distilled water at room
temperature for 24 hrs before testing. A universal testing machine (Micromet micro hardness testers) was used for testing brinell surface hardness for the three groups& for every tested material. Three tested materials was assessed by ANOVA& further exploration between all possible paired combination of tested material was assessed by bonferroni adjusted t-test p value less than 0.05 was considered statistically significant .
The statistical analysis showed that at home bleaching technique have statistically significant effect of the micro hardness of composite resin.
At-home bleaching agents have a softening effect on some tooth
colored restorative material, and the patient must be aware before using them

Abstract
The aim of this study was to determine the prevalence of dental erosion among 10-12 year old children in Mosul city, mean erosion in teeth and surfaces, amount of
carbonated beverages and fruit juice consumed in the sample, and the correlation
between dental erosion and some variables. Total sample consisted of 400 children
derived from different primary schools in the city center. Examination was performed
according to tooth wear index by Smith and Knight 1984 modified by Millword et al
1994.
Results showed that dental erosion was highly prevalent 74.2% in the sample,
increasing with increasing age, with boys showing a higher prevalence in dental
erosion compared to girls with significant difference. Mean erosion scores for primary
teeth were slightly less then permanent teeth, with a significant difference between 10 and 12 years of age for both dentitions.
Buccal/labial surfaces exhibited more erosion, followed by lingual/palatal and finally occlusal /incisal surfaces, with boys showing more erosion in all surfaces than girls. A large proportion of the sample consumed carbonated beverages 3-5 /week with boys consuming more than girls as seen in the erosion group, fruit juice was also largely consumed by the sample, especially the group that showed erosion. A positive correlation was found between erosion, level of father’s education, time of drinking,
method, amount of carbonated beverages and fruit juice consumed.
Preventive measures are considered to be the only effective course of management
of dental erosion, by reducing intake of carbonated beverages and fruit juice, also modification of erosive drinks, medicines and foods may prove to be an acceptable future strategy world wide

Clinical and animal experiments have demonstrated the role of masticatory muscle function in normal and abnormal dentofacial development. This study was aimed at observing the role of antagonistic tooth contacts in the value of maximum bite force among a sample of Iraqi children and to seek the existence of a correlation between
maximum bite force and the angulations of the mandibular incisors.
Maximum bite force was measured in 46 children (23 males and 23 females). The
teeth that occluded with its antagonist were counted clinically and the children were
then classified as those with full contact of opposing teeth and those with partial
contact. The angle of inclination of the mandibular incisors was obtained by cephalometric lateral views for each child.
Maximum biting force was higher in children with full contact of teeth than in
children with partial contact of teeth. The difference was statistically insignificant. A
clear correlation existed between maximum bite force and the angulations of the mandibular incisors.
Maximum biting force affected the inclination of the mandibular incisors.
No difference was found in the value of maximum biting force between patients with full contact of teeth and those with partial contacts.

Abstract
Early detection of upper canine eruptive problems, give a better chance for the preventive steps to be taken. 328 maxillary canines in pre-emergence phase, were studied on the bases of (164) panoramic radiographic records of Iraqi children age 5- 12 years (72 boys - 92 girls). Canine inclination (CI) (relative to a plane between the
suborbital points), and its relation to the lateral incisor (CLR) were studied. The lateral incisor developmental stage (LID) was evaluated too.
Results showed that, in initial stages of (LID), the canine lateral incisor relation
(CLR) is almost characterized by overlapping, a situation rarely seen in the final
stages. Only 8-15% of the overlapping is found when the lateral incisor was
completely developed (CO), detecting possible canine anomalies in this stage, especially when associated with other clinical signs as non-palpation of the cuspid bulge in the alveolar process. Then extraction of the primary canine is advised to prevent impaction

This study was designed to assess the microscopical changes of the enamel surface
before and following the treatment with different concentration of metal salts,
involving zinc, strontium, magnesium, in addition to stannous fluoride and de-ionized water as the control.
Microscopic examination was conducted on teeth samples before and following pH-cycling procedure and following the treatment with the selected metal salt under polarized microscope (100X).
The best obvious remineralization was found following treatment with stannous fluoride, followed by zinc chloride. Samples treated with strontium chloride showed rather poorly mineralized surfaces. No signs of mineralization were observed for samples treated with magnesium chloride.
Although stannous fluoride was the best in the remineralization of initial caries, results for other metals seem to be promising if used for prevention of dental caries

One of the most important practical deficiencies of present denture base materials
is fracture, therefore many attempts have been made to reinforce of the repaired
denture base resin, a desirable objective for this service is to obtain optimum strength
for repair, which can be achieved by making available a good bound between original
and repair materials.
The present study was carried out to evaluate and compare the effect of different
surface treatments (monomer, acetone, combination monomer + acetone) on the
transverse strength of acrylic denture base.
Seventy (70) specimens were prepared from pink heat-cure acrylic resin of which
(10) specimens were considered a control group. The remaining specimens were
divided into two main groups (30specimens repaired by Ivomat and 30 specimens repaired by air method).
The joint treated before cold-cured acrylic resin was applied to the joint space.
Specimens were repaired by cold-curing resin (major). Then they were stored in
distilled water at (37 Co) for (48) hours. These were subjected to three-point loading
testing machine to determine the transverse strength.
The results showed that air cured acrylic resin has significant lower transverse
strength than Ivomat cured acrylic resin also show that the specimen treated with (Acetone + monomer) have a higher transverse strength.
Finally, it can be concluded that curing methods and surface treatment will
improve transverse strength of the repaired acrylic denture base resin.

Acrylic denture base is the part of the denture that rests on the foundation tissue &
to which the teeth are attached. The main objective of this study was to determine the
effect of different cleansers solution on the impact strength of heat cure acrylic resin.
Thirty (30) rectangular shape samples from acrylic were prepared with dimension of (55 mm *10 mm *2.5 mm) length, width& thickness .The acrylic was fabricated in the same conventional way for construction base palate. All the specimens were examined by vernier before immersion in solution to check the size of each samples, the samples were divided into three group (A, B& C) each group contain ten samples.
The samples in first group (A) were immersed in distilled water, the samples in
second group (B) were immersed in peroxide solution, while the sample in the third
group (C) were immersed in prepared cleanser solution (citric acid).After period of
immersion (for 3 week & 15 minutes every day).Finally each samples rinsed by distilled water & cleaned thoroughly by apiece of cotton before testing. The impact strength was tested in chapy impact machine. The statistical analysis of the results showed that there was no statically significant difference in impact strength value among the testing groups. This means that the all cleanser solution that were used in this study had no effect on the impact strength.

The calcium, inorganic – phosphate of 20 pregnant women with age (20 – 45)
years wearing removable partial denture divided into 3 trimester and 10 women
married non pregnant as control.
In resting saliva the concentration of calcium not changed significantly in pregnant women, and inorganic – phosphorus found not to be changed significantly.
The aim of this study was to see the pregnancy related change in human saliva and relation to the oral findings and effect of wearing removable partial denture.

Background: Squamous cell carcinoma of the oral cavity constituted a major health
problem and can be a leading cause of death. Several studies link high risk Human
papillomavirus -16 to oral squamous cell carcinoma as an important etiological
factor. Several molecular markers have also been the subject of an intense
research work, trying to clarify their role in oral carcinogenesis. Of these, the
cancer suppresser gene P53 has been extensively studied.
Aim of the study: to detect the association of the molecular markers Human
papillomavirus -16, in the oral Squamous cell carcinoma using in situ
hybridization technique and To correlate Human papillomavirus -16 with clinical
data (age, sex, risk factors grade &stage).
Material & Methods: Tumor tissues from 33 patients with newly diagnosed as oral
squamous cell carcinoma & who were surgically treated collected, formalin fixed & paraffin embedded. Sections on charged slides were made from each tissue block and submitted to in situ hybridization technique utilizing Human papillomavirus -16, cDNA probe.
Results: Human papillomavirus -16 was localized by in situ hybridization
specifically within the nuclei of cancer cell it was detected in (27) (81.8%) of 33
oral squamous cell carcinoma patients. Most of Human papillomavirus -16
positive patients were within the age group (50-59) years. However, there was no significant correlation between Human papillomavirus -16 positive &age. No significant correlation was found to sex &risk factors (smoking &alcohol
consumption) either. Most of cases were moderately differentiated squamous cell carcinoma (79%). however no significant correlation was detected regarding histopathological grading or clinical staging with Human papillomavirus -16.
Conclusions: Oral HPV-16 infections are strongly associated with OSCC. Among subject with or without the established risk factor of tobacco& alcohol use

Abstract
Dental pulp tissue is a highly specialized conneclive tissue contains a formative
and protective cells that can be affected easily by stimuli such as occlusal trauma
subjected by occlusal overhang filling.
Sixteen albino rats aged range (6-8 months) weight range (0.5-0.75 kg) were
subjected the occlusal overhang filling made for upper first molar for 2 periods, and
according the periods, rats divided in the 2 groups. Groups I (8rats) subjected for occlusal trauma for 2 weeks duration group II (8rats) subjected for occlusal trauma for 8 weeks duration. Histological evaluation have been done for 2.8 weeks using hematoxyline and eosin stain.
Occlusal trauma for 2 weeks in group I showed wide irregular predentin formation will displacement in odontoblast cell.
While in group II for 8 weeks duration, histological feature for pulp tissue showed hyalinization (50-95 μm) in length.
Occlusal trauma for long period cause hyalinization of pulp tissue that negativelyinfluence on endodontic treatment in future.

Abstract
Candida is a genus of yeast .Many species of this genus are symbiont of animals
host including humans. While usually living as commensally in oral cavity, some
candida can cause disease .The most significant member of the genus is candida
albicans which can cause infection called candidiasis or thrush especially in elderly
denture wearers.So the denture seems to be frequently the sources of fungal infection.
The current study aimed to determine the fungal prevalence rate in oral cavity
among denture wearers patients in comparison to those without dentures and also to
determine the local risk factors includes trauma due to ill fitting denture, nocturnal wear of the denture, heavy smoking and the age of the denture.
The result of this study showed that the prime etiology of candida growth was the
material of prosthesis itself. 57% of the denture wearers showed growth of candida while 22% of subjects who had their own dentitions showed candida growth that them prosthesis is the dominant etiological factors in candida growth other local factors must be considered.

Abstract
The prevalence of metabolic syndrome (MetS) is increasing worldwide, and it
appears to increase independently the risk of cardiovascular disease. Periodontitis has
been shown to have an association with the risk of cardiovascular disease.
The aim of the present study is to investigate the association between periodontal
status and the main components of metabolic syndrome, singly, and in combination in
type 2 diabetic patients.
One hundred and seventy five patients (96 males and 79 females) with type 2
diabetes mellitus (T2DM) were enrolled in the study. The following clinical
characteristics were reported: age and gender, body mass index (BMI) and blood
pressure. Periodontal status was assessed using periodontal disease index which
includes plaque, calculus, and periodontal component of the index. An assessment of
serum lipid analytes included estimation of serum triglycerides (TG) and serum high
density lipoprotein cholesterol (HDL-C).
There was a significant difference in mean value of periodontal disease index
(PDI) between normotensive and hypertensive diabetic patients (3.31±0.83 vs.
3.82±0.65, P<0.001). Also there was a significant difference in PDI between normal
and high TG groups (3.49±0.73 vs. 3.81±0.61, P<0.01). There was a significant
increase in TG level in hypertensive compared to normotensive diabetic patients
(P<0.01). Only in presence of hypertension and obesity in addition to diabetes that
PDI was significantly increased in comparison with diabetic hypertensive non obese
patients (4.1±0.58 vs. 3.62±0.64, P<0.001). There were no significant differences in
TG level between obese and non obese diabetic patients while there was a significant
increase in TG level in patients who were hypertensive obese compared to
normotensive non obese (174.64 ±61.39 vs. 150.80±54.96 respectively, P<0.05). Presence of two or more characteristics of MetS has resulted in a significant increase of PDI when compared with patients who had only diabetes (P<0.001).
In conclusion, hypertension and hypertriglyceridemia as main components of MetS are singly associated with periodontitis in T2DM and the presence of any two studied components of MetS in addition to diabetes will attain the worst deterioration in periodontal status.

Partial recording of indices of periodontitis have long been used in clinical and
epidemiological studies to predict full-mouth situation. The two most widely used
partial recording indices for periodontal surveys are the community periodontal index
of treatment needs (CPITN) and the Ramfjord teeth.
The aim of this study was to evaluate the usefulness of Ramfjord teeth in
predicting the full-mouth periodontal status of an adult population in patient attending the collage of dentistry- Baghdad University.
The study participants were 240 patients we divide them into three main groups according to the age of the patients and each group were divided in to two sub groups according to the sex of the patients. Pocket depth was measured in millimeters with
periodontal probe The difference in the mean pocket depth measured from the full mouth(F) and Ramfjord teeth(R) by using paired t - test was non significant in all the groups. Also
in all groups the correlation coefficient as well as beta coefficient was high
The high agreement between Ramfjord teeth and full mouth periodontal pocket depth confirm the epidemiological validity of Ramfjord teeth to represent the full mouth.