MUSTANSIRIA DENTAL JOURNAL

The purpose of this in vitro study was to evaluate the combined effect of ProTaper file rotary instruments to K-flexo file hand instruments in curved canals in terms of instrumentation time, change in working length, and spreader penetration depth. Thirty curved mesial canals of extracted mandibular molars were used in this study, divided into two groups (15) canals for each group. In group I the canals were prepared with NiTi ProTaper file with slow speed contra angle hand piece (300rpm). In group II the canals were prepared by step-back technique with Gates-Glidden using stainless steel K-flexo hand instruments. Students\'t-test revealed that there was a highly significant difference between group I and group II in preparation time, and change in working length. In group II spreader penetrated significantly closer to working length than in group I.

It is of utmost importance that the clinician be familiar with the variations in root canal anatomy and the characteristics features in various racial groups, since such knowledge can aid location and negotiation of canals as well as their subsequent management. The aim of the present study is to investigate the incidence of three roots and four root canals in the mandibular first molar in Iraqi population. A total of 327 endodontically treated mandibular first molars were investigated in this study. Radiographs of working length determination and canal obturation at different angles of each tooth were mounted, projected and evaluated. The clinical records were reviewed and the findings for the number of roots and root canals were then recorded and tabulated. Roots with multiple canal systems were categorized according to whether the canals exited the root by a common apical foramen or by separated apical foramina. The results showed that 81.96% of the examined teeth had three root canals and the remaining 18.04% had four root canals. Most of the teeth ( 99.08% ) had two roots. Only three teeth ( 0.92% ) had three roots. There was no significant differences between males and females in the incidence of three roots and four root canals ( P > 0.05 ).

The purpose of this study was to evaluate the potential of using mineral trioxide aggregate (MTA) as a root canal filling material by comparing its apical sealing ability with that of laterally condensed gutta-percha with sealer in extracted one canal teeth. In addition, this study was evaluating the MTA and ZnPo4 cement as barriers to coronal microleakage.
Forty single canal extracted teeth, were prepared in a standard manner using GT file, randomly divided into two groups of 20 teeth, and obturated with laterally condensed gutta-percha or MTA.
In each group, 10 teeth received a 4-mm barrier of MTA or ZnPo4 cement. The sealing ability of each part was assessed by immersion in 1% methylene blue dye for 72 h. The leakage was recorded in apical and coronal part. Data were analyzed by One-Way ANOVA test, T-test, and LSD test.
Canal filled with laterally condensed gutta-percha showed significantly less apical dye penetration than canals obturated with MTA. However, coronal barrier filled with MTA showed significantly less dye penetration than ZnPo4 cement barrier.

In this study, the relationships between the over bite and the structure of the frontal alveolar and basal bone were investigated. The over bite, lower face height, and the anterior alveolar and basal midsagittal cross-sectional area from the maxilla and the mandible were assessed on lateral cephalograms from (88) un-treated subjects. The open bite group showed significantly larger maxillary and mandibular alveolar and basal cross sectional areas compared with the normal over bite group. It is concluded that open bite subject with long face have a larger mandibular and maxillary alveolar height, which is more associated with elongated and narrowed shape of the symphysis.

Background : Streptococcus mutans has been implicated as a principle microbial agent in the pathogenesis of dental caries. The aim of this study was to compare caries experience and salivary Streptococcus mutans count among groups of children having primary dentition and adults having permanent dentition.
Materials and Methods: The sample consisted of 100 children with an age of 4 – 5 years old and 100 adults with an age of 21 – 22 years old in Baghdad city. Dental caries was examined for the whole dentition and bacteriological analysis was done for the salivary sample to estimate the count of Streptococcus mutans in saliva.
Results: Caries experience of adults was significantly higher than that of children while salivary S.mutans count was significantly higher among children than the adults. Positive correlation of S. mutans with decayed surface was stronger than that with (dmfs/DMFS) for both children and adults.
Conclusion : S. mutans count was significantly higher among children than adults and caries experienc of permanent teeth was significantly higher than that of primary teeth.

Endocarditis is a localized microbial infection of the heart valves or endocardium adjacent to congenital or acquired heart defects. It is the dentist\'s responsibility to prevent the occurrence of endocarditis by following the latest recommendations usually issued by the American Heart Association on prevention of endocarditis. The purpose of this investigation was to determine the role of Dentistry in causing endocarditis among Iraqi at risk patients. A retrospective study of patient\'s records in three major hospitals in Baghdad was done. Thirty three cases of bacterial endocarditis were found and examined .The results indicated that (18%) of cases were preceded by dental procedures. Compliance with the guidelines on prevention of endocarditis is necessary for all at risk patients.

Since the conventional radiograph was introduced in 1901, it seems that it has wide spectrum in it use in medical, dentistry & engineering branches.
The importance came from its value in diagnosis and predicate the causes of different effects. This lead to more researches for more advanced programs , which continued through last century lead to an advanced radiography like digital one, C.T. scan and M.R.I. Still the conventional radiographs are the baseline for this progress a far farther for future progression.
Aim of the study is to prove a new approach in \"Bisecting angle technique\".
The present study indicate the new approach in using the bisecting angle technique since the old one give instructions on three main lines:-
A. Patients positioning in the dental chair.
B. Positioning of dental intraoral film inside patient mouth.
C. The position of the cone of X-ray machine in both vertical and horizontal angles.
But Al-Safi method gives instructions number D- about the anatomical landmarks that lead to the apex of the tooth to which central beam is directed, by drawing a line from ala of the nose to the tragus of the ear called ala tragus line indicate the apecies of maxillary teeth , for the mandibular arch a line draw indicate apices of mandibular teeth from the angle of the chin to the angle of the mandible in proper manner.
In present study, two groups of fifth years students in the college of Dentistry in Baghdad had been taken. The first group had given instructions A-B-C-, second group had given instructions A-B-C- and D- according to Al-Safi method.
The statically analysis using t-test shows , a significant difference between the first and second group in the effectiveness of sharpness and allignments artifacts , from the same point of view there were no significant difference between members of second group while there is a significant difference between members of the first group.
The results indicate that the new approach in instructing the second group of students were gave wide predictors for their work and better results in decreasing the technical errors and dental artifacts.

Background: In this study forces required to dislodge a maxillary complete denture were compared for different types of posterior palatal seals \" Group 1 single beading design , Group 2 double beading design and group 3 with butter fly posterior palatal seal.
Materials and Methods :Using a specially designed strain gauge force transducer and strain measuring device ,the force required to dislodge a maxillary complete denture measured and compared. Ten male subjects are selected with age range 55-65 yrs, the primary impression made in the usual manner and the final impression made with zinc oxide euogenol paste after the border seal made with tracing stick impression compound ,then the master cast duplicated using a heavy body silicone impression materials in order to produce a three additional casts, then the casts scraped to incorporate the posterior palatal seals and produce the three groups .a denture base constructed after postdum scraping.
Results: Comparing the three groups the results shows that a significant difference found between the group 1 and 2 and group 1 and 3 with no significant difference found between group 2 and 3. Using ANOVA Table with LSD.
Conclusion: No Design Provide superior priority than the other type of posterior palatal seals but a double beading and butter fly posterior palatal seal can improve the retention of a maxillary complete denture.

Aims of the study: To identify the must appropriate type of dental stone produces with minimal setting expansion
Materials and methods: Three typee of dental stone compared, two groups produced depending on the mixing ratio so that the setting expansion values obtained by the aids of extensometer then compare them statistically.
Results and discussion: Comparing setting expansion within each group the lowest setting expansion found in Elite model stone while the highest value in Silky Rock model, in Q.D. dental stone While comparing the two groups with each other shows no considerable changes take place due to increase in the W/P ratio
Conclusion: Increasing the W/P ratio to a considerable limit results in a minimal changes in the setting expansion for Silky Rock stone, while for Q.D. dental stone & Elite model the setting expansion decreased. Heat generated from the mixture didn't affected by the changes in W/P ratio.

Sixty-six patients have been diagnosed and distinguished as having destructive periodentitis out of one thousand slowly growing chronic periodontitis (S.G.Ch.P.), constituted 6.6%, females was 68.18%, male was 31.81%, a significant difference was found between male and female.
Possible activating and inverting factors was studied, restraint stress and depression appear having a significant relationship, nutritional factor as well showed a significant influence on inversion of S.G.Ch.P. into DP.
High gingival index, sever bone destruction; deep packet and an eventual tooth mobility with generalized distribution pattern were the characteristic clinical feature of the disease.
In conclusion local bacterial and systemic conditions either psychic or somatic may interfere in the activation and inversion of the adult periodentitis into destructive periodontitis under the basis of systemic and psychological factors .

A thorough investigation of the occurrence of malocclusions among schoolchildren would be of major importance in the planning of orthodontic treatment in the public dental health services. For this purpose it is necessary to have available detailed information on the prevalence of individual malocclusions among students at different ages and more over , an analysis of the need for orthodontic treatment in the different school classes .
The sample consisted of (4808), 13-18 years old student taken from Baghdad intermediate and preparatory female schools. A clinical examination was used to determine the prevalence of occlusal features and the need for Orthodontic treatment based on the definitions of grades for the Index of Orthodontic Treatment Need (IOTN).
Of the sample (29.68%), (17.55%), (16.7%), (26.04%). In addition (10.02%) have been categorizer under Grad 1 (No need), Grad 2 (little need), Grad 3 (moderate need), Grad 4 (great need) and Grad 5 (very great need) respectively. The statistical differences between these grades were non- significant (P> 0.05). The scarcity of orthodontic treatment may be explained by the lack of dental health education programs , lack of a health insurance system concerned with orthodontic treatment in Iraq , history of failed orthodontic treatment and most of general practitioners favor not to advice , motivate and refer the patient for orthodontist.

The goal of this study was to determine how air-inhibited layer and time affect the interfacial bond strength when immediate and delay light cure composite repair was done using micro filled composite (helioprogress kit, viva dent, Germany).
In group A there was no air-inhibited film on the surface of the initial layer of restoration, while in group B an air-inhibited layer was present. In both groups the surface layer was abraded and divided into further subgroups.
Sub-group I: repair was done immediately after storage in distilled water of 37oC for 15 min, whereas in Sub-group2: delay repair was done after storage for 1 week.
Result showed significant difference between the immediate and delay sub-group in both groups, while there was no significant difference with or without air-inhibited layer when immediate and delay repair was done.

The aim of study was to evaluate the effect of dietary habits (frequency of sweet consumption per day, pattern and type of sweet consumption) on dental caries prevalence on primary and permanent teeth.
The study was conducted on (286) primary school children, (132) boys and (154) girls 6-12 years old. Assessment of the dental caries were performed according to the basic method of the oral health survey of WHO. The recording of dental caries was performed using DMFT and deft indices.
The result showed that the mean DMFT for the total sample was (2.20) and for deft was (2.21). the boys reported less mean DMFT than girls with significant differences between them, while boys reported high mean deft than girls with no significant differences between them.
The result indicated that the pattern of eating sweets in between meals was found to be of predominant behaviors. Also the result demonstrated that the group eat sweet between the meals have highly significant mean DMFT and deft than the other groups.
The study revealed that the frequency of sugar consumption per day was 5.9 in girls and 4.7 in boys and the predominant form of frequency sweet eat was sweetened beverage followed by sticky foods. The mean DMFT and deft was highly significant in group eat (sticky foods, beverage sweetened and non-Sticky foods) than the group eat only (non-sticky foods and beverage sweetened).
From the findings of this study reducing sugar consumption, reducing the frequency of sweet consumption specially between the meals and avoiding sticky foods is an important part of caries prevention.

In this study an attempt was done for correction of the alveolar bone defect that result from the surgical enucleation of periapical cystic lesion in the premaxillary region, by using autogenous symphysis bone graft.
Forty six patients were collected from different places of Iraq .A twenty nine patients from College of Dentistry / University of Baghdad, Fifteen patients were collected from private Clinic, and two patients were collected from College of Dentistry /University of Sulaymania in the period from (Feb. 2003-Jan.2005). The average age of the patients was ranged from (29-43) years of old, 33 were males and 13 were females. Surgical enucleation of periapical cystic lesion was done for all cases with measurement of mesio-distal dimension, superio-inferior dimension for the surgical wound of the cystic lesion. The labial alveolar bone defects were closure by autogenous symphysis bone from the lower jaw of the same patient by second operation. The region of symphysis bone graft was filled by Frios Algipore.
The results of the present study shows that osseointegration of symphysis bone graft in the region of post-surgical removal of periapical cystic lesion have a moderate healing during the first month 19 (41.3%). A significant osseointegration of symphysis bone graft after 6 months, which revealed an excellent healing process 36 (78.3%). A highly significance of osseointegration of Algipore augmentation occurs in the symphysis region 37 (80.4%).

The goal of this study was to determine how air-inhibited layer and time affect the interfacial bond strength when immediate and delay light cure composite repair was done using micro filled composite (helioprogress kit, viva dent, Germany).
In group A there was no air-inhibited film on the surface of the initial layer of restoration, while in group B an air-inhibited layer was present. In both groups the surface layer was abraded and divided into further subgroups.
Sub-group I: repair was done immediately after storage in distilled water of 37oC for 15 min, whereas in Sub-group2: delay repair was done after storage for 1 week.
Result showed significant difference between the immediate and delay sub-group in both groups, while there was no significant difference with or without air-inhibited layer when immediate and delay repair was done.

Class III malocclusions are considered one of the most complex and difficult orthodontic problems to diagnose and treat. The aim of this study was to quantify the facial profile deviation of class III from almost norms cases. A comparative study of 26 class I and 31 class III subjects at age range of 18-26 years was performed using a lateral cephalometric radiograph.
The results revealed that the facial height (upper, lower and total) in female is not affected by skeletal pattern of class III than class I. While in male, a significant decrease in upper facial height and a significant increase in lower facial height in class III adults with a non-significant differences in total facial height than class I samples. In addition, class III subject exhibited significant increase in both skeletal and soft tissue convexity angles. Furthermore, longer and thinner chin with a more flattened labiomental fold angle and a more flat feature of chin in the patient with class III than class I patient, except for female in class III who show a non-significant decrease in chin thickness than class I.