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Article
The relation of anterior and lateral cranial base lengths with mandibular morphology and facial heights

Author: Yassir A. Yassir
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2008 Volume: 20 Issue: 2 Pages: 88-92
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: The cranial base is important in integrated craniofacial development and growth-especially the anterior cranial base, which has direct connections with the upper-middle face and integrates with the facial elements into a growth complex (ethmomaxillary complex). The aim of this retrospective cephalometric study is to find the relation between anterior (S-N) and lateral (S-Ar) cranial base lengths with mandibular morphology and facial heights.
Materials and method: The sample included 153 pretreatment digital lateral cephalometric radiographs of Iraqi orthodontic patients who attend the Department of Orthodontics in the College of Dentistry-University of Baghdad. The sample divided according to the ANB angle into skeletal Cl I (40 females and 35 males), and Cl II (40 females and 38 males). Nine linear measurements were digitized and recorded using AutoCAD 2007 computer program, the data then analysed by SPSS version 15.00 computerized statistical analysis.
Results: Males had higher mean values for anterior and lateral cranial base lengths than females, with no significant difference between classes. Mandibular morphology and anterior facial heights positively correlated with anterior cranial base especially in males. Lateral cranial base positively correlated with posterior facial height in males and females, and with mandibular body length and total mandibular length in males.
Conclusions: The effect of gender was greater than the effect of skeletal classes for the anterior and lateral cranial base lengths. Anterior cranial base was mainly positively correlated with anterior facial heights in both genders, while lateral cranial base mostly correlated with posterior facial height.
Keywords: Anterior cranial base, mandibular morphology, facial heights (J Bagh Coll Dentistry 2008; 20(2):88-92)

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Article
RAMUS HEIGHT AND ITS RELATIONSHIP WITH SKELETAL AND DENTAL MEASUREMENTS

Author: Yassir A. Yassir
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2013 Volume: 1 Issue: 1 Pages: 1-5
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Background: The purpose of this study was to assess mandibular ramus height and to assess the relationship of ramus heightwith various craniofacial and dental measurements in a sample of Iraqi adults with skeletal and dental Class I.Materials and method: The sample consisted of 95 Iraqi adults (54 females and 41 males) having normal occlusion andClass I skeletal pattern aged between 18 and 31 years. Each individual was subjected to clinical examination and digital truelateral cephalometric radiography. The radiographs were analyzed using AutoCAD 2007 software computer program to de- termine ten linear and seven angular measurements. Descriptive statistics were obtained and independent samples t-test wasperformed to evaluate the gender differences, while Pearson’s correlation coefficient test was used to identify correlationsbetween ramus height and other measurements.Results: All linear measurements were significantly higher in males, while angular measurements showed non-significantdifferences between males and females, except for SN-MP, SN-PP, and N-S-Ar angles which were significantly higher in fe- males than in males. For both genders, there were significant positive correlations between ramus height and posterior facialheight, maxillary and mandibular molar dentoalveolar heights, while there were significant negative correlations with SN-MP,PP-MP, and Ar-Go-Me angles. Ramus height in females showed a significant positive correlation with N-S-Ar angle, and asignificant negative correlation with S-Ar-Go angle.Conclusions: Ramus height was directly correlated with intermaxillary space in the posterior region, and inversely correlatedwith angles of mandibular rotation.


Article
Mandibular antegonial notch depth distribution and its relationship with craniofacial morphology in different skeletal patterns

Authors: Ausama A. Al-Mulla --- Yassir A. Yassir
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2009 Volume: 21 Issue: 1 Pages: 107-111
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: Antegonial notch is a small concavity at the inferior surface of the mandible. The purpose of this study is
to identify the distribution of mandibular antegonial notch depth and its relationship with craniofacial morphology in
different skeletal patterns.
Materials and method: The sample included 191 pretreatment digital lateral cephalometric radiographs (93 males,
98 females) collected from the Orthodontic Department in the College of Dentistry, University of Baghdad. The
sample was divided into three groups according to the skeletal classes, and then each group divided according to
depth of mandibular antegonial notch into: shallow, medium, and deep groups. Sixteen angular and thirteen linear
measurements were used.
Results: Cl I had the highest percentage of medium antegonial notch. Cl II had the highest percentage of deep
notch, while Cl III had the highest percentage of shallow notch. Males had significantly deeper notch than females in
Cl I and Cl II. Significant difference found between males skeletal Cl II and Cl III. The craniofacial measurements
showed significant changes with the increase in antegonial notch depth variably in different classes.
Conclusions: Angular measurements of cranial base more concerned with mandibular morphology than linear
measurements. The increase in vertical growth pattern and backward rotation of the mandible in association with
the increase in notch depth appeared particularly in skeletal Cl II.
Keywords: antegonial notch, craniofacial morphology, skeletal patterns. (J Bagh Coll Dentistry 2009; 21(1): 107-111)

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Article
Simulated canine retraction with different sizes of stainless steel archwires (An in-vitro study)

Author: Yassir A. Yassir ياسر عبد الكاظم ياسر
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 1 Pages: 146-150
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study aimed to assess five different sizes of archwires regarding canine retraction and distopalatalrotation in an invitromodel.Materials and method: A total of 50 acrylic canine teeth were fabricated as a replica to a natural tooth, to which0.022×0.030 inch slot standard edgewise brackets were bonded. They were ligated to straight .018 inch, 0.016×0.022inch, 0.017×0.022 inch, 0.018×0.022 inch, and 0.019×0.025 inch stainless steel archwires using loose steel ligature wire.The teeth were moved through softened wax (at 50°C) along the archwires using NiTi closed coil springs then theamount of tooth movement, and the degree of rotation were measured.Results: The descriptive statistics showed that the maximum distance of canine retraction and rotation was with 0.018inch wire, while the minimum was with 0.019×0.025 archwire. For canine retraction only a non-significant differencesbetween 0.016×0.022 and 0.017×0.022 archwires and between 0.018×0.022 and 0.019×0.025 archwires were found,while for canine rotation the non-significant differences were between 0.017×0.022 and 0.018×0.022 archwires andbetween 0.018×0.022 and 0.019×0.025 archwires as detected by ANOVA test and post hoc Scheffe test. Pearsoncorrelation coefficient test revealed non-significant correlation between the distance moved by the canine and itsdegree of rotation.Conclusion: The greatest amount of canine retraction and rotation achieved with 0.018 inch stainless steel archwire,while the opposite occurred with 0.019×0.025 inch wire. 0.017×0.022 inch archwire combined properties acceptableboth regarding canine retraction and rotation.

المقدمة: ھدفتْ ھذه الدراسةِ لتَقییم خمسة أحجام مختلفةَ من أسلاك التقویم فیما یتعلق بسحب ودوران الناب في دراسة مختبریة.0.030 بوصةِ. وتم ربطھا الى × المواد والطریقة: ما مجموعھ 50 ناب أكریلیكِ صُنِعتْ كنسخة طبق الأصل إلى سنّ طبیعي، ولصقت علیھا حواصر بقیاس الشق الداخلي 0.0220.025 بأستخدام روابط × 0.022 بوصة، و 0.019 × 0.022 بوصة، 0.018 × 0.022 بوصة، 0.017 × اسلاك تقویم فولاذیة مقاومة للصدأ مستقیمة بقیاسات 0.018 بوصة، 0.016معدنیة فضفاضة. حُرّكتْ الأسنان خلال الشمعِ الناعمِ في 50 درجة مئویة بواسطة نوابضحلزونیة مغلقة من مادة النیكل تیتانیومِ، ثمّ قِیستْ كمیة حركةِ السنِّ ودرجة الدورانِ.0.025× النَتائِج: أظھر الإحصاء الوصفي بأنّ المسافةَ القصوى لحركة ودوران الناب كَانَ مع سلك التقویم بقیاس 0.018 بوصةِ، بینما الحَدّ الأدنى كَانَ مع سلك التقویم بقیاس 0.0190.025 . بینما لدوران الناب، × 0.022 و 0.019 × 0.022 ، وبین 0.018 × 0.022 و 0.017 × بوصة. فیما یخص حركة الناب وُجدت أختلافات غیر ھامة فقط بین الاسلاك بقیاس 0.0160.025 ، كما توضح بإختبار أنوفا وبعد ھذا إختبار شیف. كَشفَ إختبارُ معاملِ × 0.022 و 0.019 × 0.022 وبین 0.018 × 0.022 و 0.018 × الإختلافات غیر الھامّة كَانتْ بین 0.017إرتباطِ بیرسون وجود إرتباط غیر ھامّ بین مسافةِ تَحرّكَ النابِ ودرجة دورانھ.0.025 بوصةِ. سلك التقویم × الخلاصة: الكمیة الأعظم لسحب ودوران الناب أنجزا بسلك التقویم الفولاذي المقاوم للصدأ 0.018 بوصةِ، بینما العكس حَدثَ مع السلك بقیاس 0.0190.022 بوصة یجمع خصائصمقبولةَ فیما یخصسحب ودوران الناب


Article
Wits appraisal and Tweed triangle for a sample of Iraqi adults

Authors: Noor F. K. Al-Khawaja --- Yassir A. Yassir --- Mohammed Nahidh
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: 4 Pages: 134-140
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: This study aimed to establish the normal value of Wits appraisal and Tweed triangle for a sample of Iraqi
adults and to verify the existence of sexual dimorphism.
Materials and Methods: 95 dental students (41 males and 54 females) having normal occlusion and acceptable
facial profile were chosen for this study. Each student was subjected to clinical examination and digital true lateral
cephalometric radiograph. The radiographs were analyzed using AutoCAD 2007 to measure the distance
representing the Wits appraisal and the angles representing Tweed triangle. Descriptive statistics were obtained for
the measurements for both genders separately and for total sample; independent samples t-test was performed to
evaluate the gender difference.
Results: The results indicated that the mean value of Wits appraisal was higher in males than females with a nonsignificant
difference between both genders, on the other hand, the Frankfort- mandibular plane angle was higher in
males than females while the Frankfort- mandibular incisor angle was higher in females than males and mandibular
incisor- mandibular plane angle was nearly similar in both genders with a non-significant difference.
Conclusions: The normal values of Wits appraisal and Tweed Triangle were established. The Iraqi sample showed Wits
appraisal of females near to that of Jacobson while of males was higher. Regarding Tweed triangle, both genders
showed more proclination of lower incisors than of Tweed with a Frankfort- mandibular plane angle near to that of
Tweed.
Key words: Tweed triangle, Wits appraisal. (J Bagh Coll Dentistry 2011;23(4):134-140).

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Article
An in vitro evaluation of shear bond strength of chemical and light-cured bonding materials with stainless steel, ceramic, and sapphire brackets

Authors: Yassir A. Yassir --- Ammar S. Kadhum --- NoorM.H. Garma
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: 2 Pages: 133-138
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: This study was intended to compare shear bond strength of chemical and light-cured bonding
materials with stainless steel, ceramic, and sapphire brackets, and to measure adhesive remnant index after
debonding.
Materials and method: Sixty non-carious, free of cracks upper first premolar teeth, which have been extracted from
18-25 years old Iraqi patients seeking orthodontic treatment were selected. Three types of orthodontic brackets were
used in this study: stainless-steel, ceramic, and sapphire brackets. All bracket types used were of standard edgewise
system. The teeth were divided into two groups of 30 teeth each. One group was used for testing the chemicallycured
primer-activated resin of no-mix type, while the other was used for testing of the light-cured resin. The
chemically and light-cured groups were further subdivided according to bracket type into three groups of 10 teeth
each. The samples were tested for bond strength using an Instron universal testing machine, while for adhesive
remnant index the enamel surface and bracket base of each tooth were inspected under magnifying lens (20X) of a
stereomicroscope.
Results: The highest shear bond strength values were found in sapphire brackets followed by stainless steel and
ceramic brackets respectively, both in no-mix and light-cured groups as revealed by ANOVA test. T-test showed that
the shear strength values were higher for all light-cured groups as compared to no-mix groups.
Conclusions: Sapphire brackets have the highest shear bond strength as compared to stainless-steel and ceramic
brackets. Light-cured resin has better bonding properties than no-mix resin.
Key words: Shear bond strength, stainless steel, ceramic, sapphire. (J Bagh Coll Dentistry 2011;23(133-138).

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Article
The relation between ramus notch depth and some of the craniofacial measurements in different skeletal patterns

Authors: Ali Ismail Al-Bustani --- Yassir A. Yassir --- Sami K. Al-Joubori
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2009 Volume: 21 Issue: 4 Pages: 104-108
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: This study was designed to investigate the relationship between the ramus notch depth and some of the
craniofacial measurements in Iraqi adults with skeletal Cl I, Cl II and Cl III; and to find out if there were any differences in
the ramus notch between the skeletal classes.
Materials and method: The sample consisted of 174 pretreatment digital lateral cephalometric radiographs of Iraqis aged
between 18-25 years old (85 females and 89 males). Seven linear and six angular measurements were analyzed using
AutoCAD (2007) software computer program. Descriptive statistics and gender differences were done for the
measurements. ANOVA test compared the ramus notch depth between the skeletal classes, while Pearson correlation
coefficient test was used to identify the correlations between ramus notch depth and other measurements.
Results: From linear measurements only the ramus notch depth was not significantly different between genders. Nonsignificant
differences of the ramus notch depth between the skeletal classes were revealed by ANOVA test. Significant
positive correlations of the ramus notch depth were found with the ramus length, total anterior facial height, lower
anterior facial height, posterior facial height and the saddle angle for the total sample.
Conclusions: The ramus notch depth is not affected by gender or sagittal jaws relationship. The increased ramus notch
depth may be one of the signs of the long face syndrome without openbite. Deep ramus notch is associated with the
mandibular retrusion or backward position of the ramus.
Key words: Ramus notch, craniofacial measurements. skeletal patterns. (J Bagh Coll Dentistry 2009; 21(4): 104-108).

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Article
Time-related salivary cathepsin B levels and periodontal status in different orthodontic force magnitudes

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Abstract

Background: Biologically active substances, such as Cathepsin B (CAB) which is a lysosomalcystein protease may beinvolved in periodontal metabolism in the degradation of organic bone matrix containing collagen fibers in responseto mechanical stress from orthodontic appliance. The aims of study were to determine and compare salivary levelsof CAB, pH as well as clinical periodontal parameters (Plaque index PLI and gingival index GI) with differentorthodontic force magnitudes at different time intervals.Materials and methods: A twenty-four patients (both gender) with age range (17-23) years had Angle's Class IIdivision 1 malocclusion with GI <0.5 enrolled in this study. The level of salivary CAB and pH, in addition to the clinicalperiodontal parameters (PLI and GI) were measured before (baseline), 1 hour (1H), 1 day (1D), 1week (1W), 2 weeks(2W) and 3 weeks (3W) after fixed orthodontic appliance placement with different forces applied to the teeth (F1 (40gm), F2 (60 gm) and F3 (80 gm)).Results: The highest mean concentration of salivary CAB was (12.057) at F1 in 1D visit with highly significantdifferences among the visits as well as among the forces (p≤0.05). Weak correlations were revealed between all pairsof forces as well as between each visit with the baseline visit about salivary CAB except the strong negativecorrelations between F1 with F3 at 3W and baseline with 3W visits at F3. Maintenance of good oral hygiene duringthe study period demonstrated that the highest mean values of PLI and GI were (0.2) and (0.25) respectively, inaddition to the non-significant differences regarding pH among the visits.Conclusion: The concentration of salivary CAB was increased following fixed orthodontic appliance insertion. Thevery light continuous orthodontic force could produce significant increase of this enzyme activity and give enougheffectiveness to produce tooth movement as compared to the higher forces


Article
Size and Morphology of Sella Turcica in Iraqi Adults

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Abstract

AbstractTo measure the size and describe the morphology of sella turcica on true lateralcephalometric radiographs; and to determine if there is any statistical significantdifference in the size of sella turcica regarding the genders and skeletal classes.The sample included 130 pretreatment digital lateral cephalometric radiographs(67 female and 63 males) with an age range between 17-25 years, collected from theOrthodontic Department in the College of Dentistry, University of Baghdad. Thesample was divided according to ANB angle into 3 skeletal classes. The size of sellaturcica (length, depth, and diameter) was measured and its morphology wasdetermined. Frequency distribution and percentage described the morphology,independent samples t-test was used to test genders difference, while ANOVA testwas performed to show if there is any statistical significant difference in the size ofsella turcica among the skeletal patterns.Males had slightly higher sella turcica measurements than females with a nonsignificantdifference between genders; on the other hand, class III sample had highersella turcica measurements with a non-significant difference among the skeletalclasses. In addition to the normal morphology, six distinct variations of sella turcicawere identified with the highest percentage to the normal morpholgy.All the linear measurements of the sella turcica were within standard range.Neither gender nor skeletal patterns showed significant differences in sella turcicalinear measurements. Normal morphology of the sella turcica was found in themajority of subjects.


Article
Assessment of sagittal lip position and some affecting factors in a sample of Iraqi adults

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Abstract

This study aimed to determine the sagittal lip position and some of the factorsaffecting it regarding the gender differences, and their correlations in a sample of Iraqiadults.Sixty two participants (37 females and 25 males) collected among dental studentshaving Cl I skeletal and occlusal relations and full permanent dentition regardless thethird molars were chosen for this study. Each person was subjected to clinicalexamination and digital true lateral cephalometric radiograph. The radiographs wereanalyzed by using AutoCAD 2007 computer program to measure the sagittal lipposition using the soft tissue analyses of Steiner, Burstone, Ricketts, Sushner,Holdaway, and Merrifield. Descriptive statistics were obtained from themeasurements of both genders; independent samples t-test was performed to evaluatethe gender differences and Pearson’s correlation coefficient test was used to find thecontributing factors to the sagittal lip position.Sagittal jaw angles were significantly higher in males than females, while verticaljaw angle was higher in females. Lower incisors showed slight proclination in bothgenders. The mean values of H-angle and revised H-angle in males were nonsignificantlyhigher than that of females, while the mean value of Z-angle was nonsignificantlyhigher in females. Upper and lower lips thickness mean values weresignificantly higher in males. Females had non-significantly more projected nosecompared to males. Regarding the sagittal lip position, upper and lower lipmeasurements were non-significantly higher in males than females in Ricketts,Steiner, Burstone, and Holdaway analyses, but it was significant in Sushner analysis,while Z-angle of Merrilfield was non-significantly higher in female sample. Pearson’scorrelation coefficient test revealed that upper and lower lip thickness wassignificantly positively correlated with sagittal lip position, while nose projection wassignificantly negatively correlated.Sagittal position values of the upper and lower lips in a sample of Iraqi adults areclose to the norms of Ricketts, Steiner, Sushner, Burstone, and Holdaway analyseswith a slight tendency of upper lip toward retrusion and lower lip toward protrusionwith the exception of that when compared with Sushner norms. In addition to the chinposition, lips thickness and nose projection are the most important factors thatinfluence the sagittal lip position and compensate for the variations in the jaw basesbetween genders.

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