MUSTANSIRIA DENTAL JOURNAL

The aim of this study was to compare the fracture resistance of roots following
root canal therapy using stainless-steel hand instrumentation (SS), Rotary Profile (PF)
instrumentation, Rotary ProTaper instrumentation (PT). Forty-five mandibular
premolars teeth were divided into three groups of 15 teeth each, according to the type
of instrumentation. All root obturated with gutta-percha and AH26 sealer. The roots
were vertically loaded using a universal testing machine. Fracture loads were analysed
by ANOVA and LSD test, and fracture patterns were analyzed with Chi-Square.
Profile & ProTaper groups have significantly lower fracture load than hand
instruments group (P < 0.05). Chi-Square showed a significant differences between groups (P < 0.05) .

Background :This study was conducted to evaluate the effect of yogurt on the
surface microhardness of two types of composite resins; (Filtek™ P90 Low Shrink
Posterior Restorative, 3M ESPE,USA), and (Filtek™ Z350 Posterior Restorative, 3M
ESPE,USA).
Forty samples of composite were prepared by using cylindrical mold (2mm in
hight and 8mm in diameter )..All specimens were stored in plastic container that
contain distilled water and incubated 37cº for 24 hours before they were tested. twenty
samples of each type of composite were divided into two groups (10) for each ,
baseline measurements for surface microhardness test was taken for all composite
samples using the micromet microhardness tester (Vichers hardness tester) with a
l00g load was applied for 15 seconds in which three indentations were made for each
sample and converted into Vickers Hardness Number (VHN ) .After baseline
measurement 10 samples of each type of composite were alternately immersed
manually by holding the specimen by a pair of tweezers from its sides, , in drinking
yogurt (Activia ,KSA) and artificial saliva for 10 cycles 5 seconds each at room
temperature (25cº). This was repeated three times a day (8am,4pm,12am) at 8hours
intervals for one week. the other 10 samples for each type of composite were
immersed in artificial saliva only. The total soaking time in both drinking yogurt and
saliva was 100 seconds. After the soaking sequence was completed the specimen was
rinsed with distilled water and subjected to surface microhardness test (Vichers
hardness tester).
Descriptive statistics(mean values and standard deviations with the minimum and
maximum values and Statistical analysis of data by using student t - test for all groups
was carried out between the means of each type of composites ,the results showed a
significant reduction in VHN values (at P<0.05)of Filtek™ Z350 Posterior
Restorative composites after immersion in artificial saliva, while the (Filtek™ Z350
Posterior Restorative, 3M ESPE) composite showed a highly significant reduction in
VHN values (at P<0.01)after immersion in drinking yogurt. Filtek™ P90 Low Shrink
Posterior Restorative composites showed a non significant reduction in VHN values
(at P>0.05) after immersion in artificial saliva and after immersion in drinking yogurt.
Filtek™ P90 Low Shrink Posterior Restorative composites have highest VHN
value than Filtek™ Z350 Posterior Restorative composites, and surface microhardness
results showed that drinking yogurt highly significantly effect on the Filtek™ Z350 Posterior Restorative composites while it has non significant effect on the Filtek™ P90 Low Shrink Posterior Restorative composite

Etching and re-etching are frequently done technique to alter the tooth surface and
makes it more receptive to adhesion. This study was done to assess the effect of reetching
technique on bond strength to enamel, dentin and dentino-enamel junction.
60 extracted human upper premolars teeth were collected cleaned, sectioned at the
level of cervical line, embedded in acrylic block exposing certain grounded flat
surface of the crown and divided into 2 groups:
Group A (30 etched specimens) etched with total etch (37% phosphoric acid)
for 15 sec.
Group B (30 re-etched specimens) etched and re-etched with total etch
(37% phosphoric acid).
Both groups were subdivided into:
Subgroup 1 10 enamel specimens
Subgroup 2 10 dentin specimens
Subgroup 3 10 dentino-enamel junction specimens
A standardized cylinders of light cure composite resin were bonded, and the
specimens were stored in deionized distilled water for 24 h. and testing was done with
zwick test machine and statistically analyzed using analysis of variance test
(ANOVA) and student t-test.
The results showed non significant difference between all subgroups in group
A(etching group) and between all subgroups in group A Vs. group B subgroup 2(reetched
E), and showed a significant difference between all subgroups in group A Vs
group B subgroup 3 (re- etched EDJ) and between group B sub1&2 (re-etched E & D)
Vs group B sub 3 ( re-etched DEJ) ,furthermore there were a highly significant
differences between all subgroups in group A Vs group B sub 2(re-etched D) and
between group B sub 2(re-etched E) Vs groupB sub 2(re-etched D).
Re-etching the enamel didn’t decrease the shear bond while re-etching dentin
markedly decreased the bond strength. Further more re-etching the dentino-enamel
junction lies in between.

Abstract
Dietary awareness is an important issue in modern society. The consumption of
carbonated drinks is popular with the youth of today and the habit is carried over into
adulthood. One of the most important properties that determine the durability of
dental materials in the oral cavity is their resistance to dissolution or disintegration
and the longevity of dental restorations depends on the durability of the material and
its properties, such as wear resistance, durability of the interface between tooth and
restoration and the level of tooth destruction.
The aim of this study was to measure surface hardness of composite after storage
in dry condition and after immersion in saliva and solutions that represent the popular
diet.
Fifty disk shaped specimens (5×2mm) were prepared from Z100 universal
composite using polytetraflouroethylen mold. The specimens were divided into 5
groups (n=10) and stored for 7 days at 37 Cْ in different types of storage conditions
(dry condition, artificial saliva, coca cola, heptane and citric acid). After storage,
Brinell Hardness Numbers were calculated. The data were analyzed with one – way
analysis of variance (ANOVA) and LSD test.
There was a highly significant difference when comparing the storage agents.
Coca cola and citric acid solutions produced the highest reduction in microhardness of
composite. It was followed by heptanes, artificial saliva. The storage of specimens in dry container produced the highest Brinell Hardness Numbers. Microhardness of composites stored in dry condition was the highest value, followed by artificial saliva, heptane solution, cola soft drink and citric acid . Acid solutions have the potential to erode composite resin material and this reduction was highly significant, which means that people who consume acidic foods and drinks excessively should be aware of their esthetic restorations.

The purpose of this in vitro study was to determine whether shear bond strength
(SBS) to chemomechanically excavated dentine by Carisolv (CS) differed from the
SBS after conventional caries removal by bur (CB), with the use of the following
adhesive systems: [Total-etch (TE), etch and Compobond1, etch, prime and bonding
resin]; [Self-etch (SE), Xeno v, one component self-etching dental adhesive] and [Noetch
(NE), Compobond1, prime& bond only]. Fifty human molars with occlusal caries
were used to prepare dentin samples which were assigned to 5 groups: group I and III
the prepared samples treated by CB and CS respectively then with TE, group II and
IV the prepared samples treated by CB and CS respectively then with SE, while in group V the prepared samples treated by CS and then with NE. For each sample there was light cured composite core build up. After water storage, the samples were tested in a single-plane shear test assembly. The results demonstrated that there were
statistical significant differences with in the mode of caries removal groups and also
there were statistical significant differences between the bonding systems which affect
SBS of carious dentin at p < 0.01, with in favor of the TE over SE. The present data
demonstrate that with the use of CS on (carious dentin, there was either increase or decrease in bond strength in relation with different bonding systems.

Conventional tooth the presence of interdental papillae in the maxillary anterior
region plays a key esthetic role. The presence or absence of the interproximal papilla
is of great concern to periodontists, orthodontists, restorative dentists and to patients
The aim of the study was to determine the association between different distances
and central papilla recession
The central papilla was visually assessed in 50 adults students of age ranged between (19-25 years) in dental clinic, then by using standardized periapical radiographs for the maxillary central incisors, the following vertical distances were
measured: papilla tip to contact point (PT-CP), bone crest to contact point (BC-CP),
proximal cementoenamel junction to contact point (pCEJ-CP), bone crest to papilla
tip BC-PT(the papilla height (PH)).Interdental width (IDW) was measured
horizontally. Subjects were divided into 2 groups according to interdental width (IDW) and pCEJ-CP distance respectively: 1. (28) subjects with IDW≤2mm and pCEJ–CP >4 mm as narrow-long group 2. (22) Subjects with IDW≤2mm and pCEJ– CP ≤ 4 mm as narrow-short group.
Narrow-long group exhibited more papilla recession, (PT-CP) mean was 2.5mm and the difference was statistically significant. Positive correlations were found between (BC-CP), (pCEJ-CP), (IDW) and central papilla recession and more stronger
correlations were found with (BC-CP) (r = 0.856). Papilla height was negatively correlated with (BC-CP), (pCEJ-CP), (IDW) and stronger correlation was found between papilla height and (BC-CP) (r = -0.502)
Central papilla recession is associated with narrow interdental width and long pCEJ-CP distance, papilla presence influenced by different distances, some of them are (BC-CP), (pCEJ-CP), (IDW) distances, (BC-CP) had stronger effect on the presence of central papilla.

Abstract
Zamzam water has scientifically been proven to contain high concentration of
calcium, magnesium, fluoride and many other minerals. This study aimed to test the
ability of zamzam water to increase the resistance of enamel surface against acid
dissolution compared to sodium fluoride. Teeth sample of 15 maxillary first premolars
were randomly divided into 3 groups, study group treated with zamzam water, control
positive treated with sodium fluoride and control negative treated with deionized
water. The treatment lasted for two minutes once daily for 20 days interval. Then the
concentration of the dissolved calcium ion in the etching solution of 2N HCl was
measured by flame atomic absorption spectrometer. The amount of the released
calcium ion from zamzam water treated group was lesser than that released from
sodium fluoride treated group. However the difference was statistically not
significant. A highly significant more calcium was dissolved from the water control
group compared with the mentioned agents P<0.01. Zamzam water effectively increase tooth resistance against acid dissolution, therefore it is useful to harden enamel surface against dental caries challenge.

Nickel and chromium can cause hypersensitivity in some people , this study was
conducted to investigate the alteration in the nickel and chromium concentrations in saliva of patients with fixed orthodontic appliance.
The investigation is comprised of 45 orthodontic patients .The selected sample
divided into 3 groups. The first group consisted of 15 patients with fixed appliances in their upper & lower arches. The second group consisted of 15 patients with a fixed appliance placed only in the upper arch. The control group consisted of 15 patients who were not undergoing orthodontic treatment.
Nickel and chromium release was quantified with the use of an atomic absorption spectrophotometr. The analysis of variance was used to determine if differences existed between the nickel and chromium release according to time interval. Four samples of stimulated saliva were collected from each patient before insertion of fixed appliance, 1 week , 1month , and 2month after insertion of the appliance.
A considerable variation in the concentrations of both nickel and chromium was observed. Significant differences were found between the no-appliance samples and the samples obtained after insertion of the appliance. Nickel and chromium concentrations of saliva are significantly affected by fixed orthodontic appliances during the first 2 month of treatment.

The purpose of the current study was to evaluate the calvarial thickness parameter
in both genders, and in different skeletal patterns. The sample included 120
pretreatment digital lateral cephalometric radiographs of Iraqi subjects (60 males and
60 females) aged between 17 to 30 years, attending Orthodontic Clinic in the College
of Dentistry; Baghdad University, and private clinics in Baghdad city. The 120
radiographs were divided into 3 groups (40 radiographs for each group) according to
the ANB angles: ANB angle smaller than one degree (Class III), between two and
four degrees (Class I), and larger than four degrees (Class II), each group was further
subdivided into two subgroups according to gender (20 radiographs for each gender). Four linear measurements were used exclusively in the assessment of calvarial thickness parameter in both genders.
The mean calvarial thickness values changed from highest to lowest in sphenoid, parietal, occipital, and frontal bones respectively. In the skeletal class II malocclusion the frontal and occipital bones' thickness showed highly significant gender differences
(P<0.01) using Student's t- test, with females had thicker frontal bone than males, and
males had thicker occipital bone than females, in addition the skeletal glass II group
showed no significant gender difference (P>0.05) regarding sphenoid and parietal bones' thickness. The most vital outcomes of the present study were the frontal and occipital bones can be used as important key bones for understanding the calvarial phenotypic description and sexual dimorphism in different skeletal patterns, while the sphenoid and parietal bones can be used as reference bones for standardization of cephalometric analysis.

This study aimed to evaluate the facial proportion in a sample of Iraqi adults usingPeck and Peck analysis and to verify the presence of genders differences.
60 Arab adult subjects (30 males and 30 females) having normal skeletal and dental relation and acceptable facial profile were chosen for this study. Each individual was subjected to clinical examination and digital true lateral cephalometric
radiograph in the natural head position. The radiographs were analyzed using
AutoCAD 2007. Descriptive statistics was obtained for the variables for both genders; independent samples t-test was performed to evaluate the genders difference.
The mean values of the facial, maxillo-facial, naso-maxillary, maxillary and total vertical angles are nearly similar in both genders with a non-significant difference.
There is slight increase in the nasal angle in females and mandibular angle in males with a significant and highly significant genders difference respectively.
Both genders showed proportional faces, although there is slight increase in the nasal angle in females and mandibular angle in males.

Gingival health status survey was conducted concerning 19-23 years old students in Al- Mustansiria University / college of dentistry.
The total sample composed of 150 students (75 males and 75 females).
The clinical examination was conducted by using blunt mouth probe, following the (GI) described by Silness and Loe (1963).
Results of this study have shown that mean of gingivitis decreases with advancingn class level with a high significant difference between all classes due to higher awareness regarding prevention of dental diseases among finished dental students.
Results also show that gingivitis among males is higher than that among females for all classes because of having better oral hygiene practices than males.

This study was planned to compare some of the soft tissue measurements in
individuals with skeletal Cl I and Cl III, to find out the measurements which may be
used as a clinical diagnostic aid to discriminate between both skeletal classes.
Seventy three digital true lateral cephalometric radiographs of Iraqi adults were
divided according to the ANB angle into 38 skeletal Cl I and 35 Cl III. The soft tissue
measurements were analyzed using AutoCAD (2007) software computer program.
Descriptive statistics were used to describe the measurements, while independent
samples t-test was used to rule out gender differences and skeletal class differences.
Gender differences were found significantly in skeletal Cl I for all linear
measurements; while in Cl III the significant differences were limited to the
anteropoterior measurements only (modified profile thickness at upper lip, modified profile thickness at lower lip, upper lip thickness, and lower lip thickness), with non significant difference for vertical linear measurements (upper and lower Lip height and Mouth height). All angular measurements showed non-significant gender differences. Independent samples t-test revealed that the main differences between classes were found in the labiomental and soft tissue profile angles, which were significantly higher in Cl III than Cl I, while the modified profile thickness at upper lip was significantly higher in Cl I than Cl III, for both genders and for the total sample. Lower lip height, mouth height, and the upper lip height also showed significant differences between classes but with less importance.
The labiomental angle and modified profile thickness at upper lip can be used as diagnostic aids to discriminate whether the subject has a Cl I or Cl III skeletal relation.

Fracture or debonding of plastic teeth from the denture base are common clinical
problems, the optimal combination of acrylic resin denture teeth and microware cured
denture base resin is not well known .one hundred and twenty teeth (florident, acrylic
teeth cross-linked, china) were prepared and cured by heat cured (AkrilEks, heatcuring
resin for denture powder liquid, GuLSA LTD. Izmir-Turkey), and microware
cured (Acron mc, microwave-curing denture base resin powder liquid, GCLAB
Technologies inc. Alsip,IL60803 Japan) acrylic resin were used, then the teeth were
divided into six groups and treated with different surface treatment, the first group
received no further treatment(control); the second group treatment with diatoric
preparation; the third group treated with thinner(Turpentine-DYNA CoAT, Thinner, Netherlands); the fourth group treated with tone(Propanone, Acetone, England 99% Purity-Analyer); the fifth group were diatoric conditioned with acetone; the sixth group were diatoric conditioned with thinner;(2nd group, 5th group and 6th group had been a cutting mesiodistal retention grooves 2mm deep and 3mm wide acute into ridge lap in acrylic resin teeth. One hundred and twenty specimens were divided into two groups, first one was processed by conventional method and the other one processed by microwave method and then tested by instron universal testing machine (instron corporation 1195,canton mass).The results showed than microwave-cured resin has a significant lower shear bond strength(SBS) mean values than water bathcured resin to all denture teeth types. All surface treatment application improved
the(SBS) significantly level at(p value < 0.05), while the sixth group (diatoric conditioned with thinner) showed the highest(SBS) than other group. The types of acrylic denture resin, surface treatment and curing technique influenced the shear bond strength of the tooth to the base the results of this study influenced the shear bond strength of the tooth to the base. The results of this study indicate that diatoric condition with thinner may be recommended to be applied on the denture ridge lap prior to denture base processing.

To evaluate the effectiveness of different microwave irradiation exposure times on
the disinfection of dental stone samples immersed in different solutions, and its affect
on the dimensional accuracy and surface porosity.
Dental stone casts were inoculated with an isolate of Bacillus subtilis to
examine the efficiency of microwave irradiation as a disinfection method while
immersed in different solutions; water, 40% sodium chloride, or without immersion
for different durations. Dimensional accuracy and surface porosity were also evaluated. Significant reduction in colony counts of Bacillus subtilis were observed after 5 minutes of microwave irradiation of immersed dental casts in water and NaCl solution. No evidence of growth was observed after 10 minutes while immersed in water or NaCl solution. Dimensional accuracy of dental stone was significantly affected by immersion in water for 5 or 10 minutes during exposure to microwave irradiation while it was insignificant affected by immersed in NaCl solution, or in dry air. The surface porosity of dental stone was significantly affected by the immersed in water and NaCl solution for 5 or 10 minutes while it was insignificantly affected by dry conditions during microwave disinfection.
Immersion the dental stone casts improved the effectiveness of microwave irradiation as a disinfection method. The dimensional accuracy and surface porosity was adversely affected but within the clinical limitation.

The mental foramen is the opening of the short mental canal, through which the
mental nerve the terminal branch of the inferior alveolar nerve exits, knowing the
exact position of the mental foramen is essential in oral surgical procedures. This
study determines this position in a selected Iraqi population.
240 panoramic radiographs of Iraqi population selected from three different oral
and maxillofacial centers to identify the normal range of position of the mental
foramen, both horizontal and vertical position were studied, radiographs with any
errors or taken for patients not co inside with our criteria were excluded.
In horizontal position , 51.31% were found apical to the lower second premolar , 43.64% between the first and second premolars, 3.07% were found between second premolar and lower first molar, 1.09% were found apical to the lower first premolar, 0.87% were found between lower canine and lower first premolar.
In vertical position,60.08% were found inferior to the apex of the related tooth, 36.84% were found within the apex of the related tooth while 3.07% were found superior to the apex.
The mental foramen can be found anywhere from lower canine to the lower first molar, although 94.95% of the studied radiographs showed that mental foramen was located either between the lower premolars or at the apex of the second premolar.

The removal of impacted third molars is one of the most common procedures in
oral surgery. This is because third molars show high incidence of impaction and are
often associated with pain due to pericoronitis.
Assess the reasons for extraction and describe the type of tooth angulations and
state of eruption. Determine the association of selected factors with pericoronitis as a
reason for extraction.
A total of 256 patients having symptomatic third molars and referred to the oral surgery department for consultation, diagnosis and treatment of partially or completely impacted third molars in the mandible and maxilla were included in the sample. All these teeth were surgically treated. the most common cause of surgical extraction of third molars was pericoronitis
(86.7%). The condition occurs mostly in mandible and in the 25-29 years age group. Horizontal/transverse third molars were more affected by pericoronitis (96.9%) followed by vertical angulations (91.6%). Pericoronitis encountered more frequently with complete soft tissue impaction (93.3%).
pericoronitis was the most common cause of third molar extraction. Factors associated with increased risk of having pericoronitis include: age group 25-29 years, mandible location, Horizontal / transverse angulation type and complete soft tissue impactions.

Abstract
The application of laser is widely used in many branches of medicine and surgery.
The high energy laser has coagulating, cauterizing and destructive effect, while the
low energy laser has a bio- stimulating effect.
A hole was made using a surgical bur in zygomatic bone of four rabbits and a low energy laser was applied on zygomatic bone of experimental group and compared to control non- irradiated group.
This study showed that application of low-energy laser has a promoting effect and facilitate bone deposition in the bony defect of the experimental group when compared to control group. It may be concluded that application of low-energy laser have promoting effect on acceleration of bone healing.

Saliva is an easily collected fluid that contains locally and systemically derived
markers of periodontal disease. The purpose of this study was to compare the level of
salivary alkaline phosphatase activity in healthy subjects and patients with periodontal
disease (gingivitis and periodontitis), and to evaluate the relationship of this enzyme
with different clinical parameters in all patients included in the study.
The study included 65 patients referred to Department of Oral Diagnosis, College
of Dentistry, University of Baghdad, they were divided into three groups, 20 healthy
subjects, 20 subjects with gingivitis and 25 one with periodontitis. The clinical
parameters including plaque index (PI), gingival index (GI), probing pocket depth (PPD) and clinical attachment loss (CAL) were recorded and salivary samples collected for analysis of alkaline phosphatase (ALP) levels. A highly significant increase in mean values of clinical parameters was found in patients with periodontal disease (gingivitis and periodontitis) compared to healthy subjects, also a highly significant increase in the mean values of alkaline phosphatase activity was illustrated as the severity of periodontal disease increased. ALP level was closely related to the gingival index, probing depth and attachment loss in patients
with periodontal disease, while no relation was shown to plaque index.
Salivary alkaline phosphatase could be used as a useful marker for monitoring periodontal disease.
.

During two years period from 2009-2010 cases with oral lesions and oral diseases
were recorded and analyzed, based on clinical, radiographic and biopsy examinations.
The oral diseases were divided into 8 groups ,including 110 cases oral lesion, other oral diseases were trailing well behind ,followed by soft tissue swelling 51 cases, ,congenital anomalies48 cases ,bone diseases 45 cases ,salivary gland diseases 31,other conditions 18cases , and neuralgia 14 cases.