2024-03-29T07:18:21Z
https://eos.journals.ekb.eg/?_action=export&rf=summon&issue=11772
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
Influence of the cross section shape on the ion release and subsequent weight change of different orthodontic alloys
Nasser
Barakat
Wael
Refai
Ibrahim
Mahmoud
Hak
Kim
In this study, effect of the cross section shape on the ion release of different orthodontic alloys as well as subsequent weight changes was investigated. In vitro experiments were carried out on three different alloys: stainless steel, nickel-titanium, copper-titanium alloys. Both round and rectangular wires were utilized. The results revealed that the cross section did not have considerable impact. In case of stainless steel and nickel-titanium alloys, the round cross section revealed high ion release. However, in case of nickelcopper- titanium alloy, the rectangular cross sectional wires showed more ion release. Concerning weight changes, stainless steel wire showed more weight increase. Conversely, rectangular copper titanium wire showed weight loss.
Orthodontic wires
corrosion in orthodontics
cross section effect
2011
06
01
1
13
https://eos.journals.ekb.eg/article_78913_369d85386d50eed879c89fe3d4813322.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
A radiographic comparison of apical root resorption between Herbst and Jumper twin block bite appliances
Mahasen
Taha
Shaza
Hammad
Objectives: The objectives of this study were to compare the amount of apical root resorption after orthodontic treatment with Herbst and Twin Block Bite Jumping screw (TBBJS) functional appliances, also to determine the prevalence of root resorption in the maxillary and mandibular incisors and the dental arches. Methods: 30 patients were divided into two groups 15 patients each. The first group was treated with Herbst appliance and the second group with TBBJS appliance. After treatment, periapical radiographs were obtained of the maxillary and mandibular incisors with the long-cone paralleling technique. Root resorption was scored according to the method of Levander and Malmgren. Results: Results of the Mann-Whitney U test showed that there were no statistically significant differences between the Herbst and TBBJS groups. The amounts of root resorption were predominantly small. The prevalence of resorption for the incisors was greatest for the maxillary central, followed by the maxillary lateral, mandibular central, and mandibular lateral incisors. Conclusions: There was no difference in the amount of root resorption between the Herbst and TBBJS groups with more resorption in maxillary arch than mandibular arch.
2011
06
01
15
28
https://eos.journals.ekb.eg/article_78915_48d62e768f639ff47d06b8a99b989c5f.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
Effect of topical fluoride on the mechanical properties of force-dispensing components in orthodontics
Sara
El-kabbany
Samir
Ibrahim
Ahmed
Salama
Heba
Shalaby
Fatma
Abdel-Aziz
Compromised oral hygiene, a frequent complication with orthodontic treatment, can lead to enamel demineralization anddecay. Therefore, orthodontists commonly prescribe a daily topical fluoride. The purpose of this investigation was to study the effect of two types of fluoride prophylactic gels on: 1. The mechanical properties of nickel titanium (Ni-Ti) and stainless steel (SS) orthodontic wires. 2. Stress relaxation characteristics of conventional, memory elastomeric chains and NiTi closed coil springs. To fulfill this purpose, the studied sample was divided into three equal groups of ten according to the type of test media; acidulated fluoride agent, neutral fluoride agent and artificial saliva (control). The wires were tested in their received condition and after one hour and half immersion in the test media at 37°C. The loading and unloading elastic modulus and yield strength of the wires were measured with a 3-point bend test on a universal testing machine. The elastomeric chains and the closed coil springs were subjected to stress relaxation test. Force readings were taken at initial activation and then at time intervals 1hour, 24 hours, 1, 2, 3 and 4weeks. The results concluded that 1. Topical fluoride agents decrease the functional unloading mechanical properties of Ni-Ti and SS orthodontic wires which could contribute to prolonged orthodontic treatment. 2. Ni-Ti coil springs and memory elastomeric chains were not significantly affected. So, they are recommended in association with Topical fluoride agents for delivering steady-continuous force for a period up to four weeks.
2011
06
01
29
47
https://eos.journals.ekb.eg/article_78917_8ba63e43fed7814438f38e5736eed99e.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
Evaluation of the connecticut intrusion arch in leveling deep curve of Spee
Ahmed
El Beali
Ahmad
Hafez
Hala
Badr
The Aim of the present study was to evaluate the suitability of Nitanium Connecticut intrusion arch in leveling deep curve of Spee. The sample of this study consisted of 10 Class II division 1 growing female patients with a mean age of 13.28 (± 1.43). Lower short 0.017 x 0.025 inch nitanium Connecticut intrusion arches were used for all patients after the teeth had been initially aligned. Superimposition of lateral cephalograms taken before and after leveling for each patient was made to determine the anteroposterior and vertical displacement of the lower incisors as well as the vertical position displacement of lower first molar. Statistical paired t- test was done to determine significant difference between the pre-leveling and post-leveling measurements. In the present study the lower incisors were significantly intruded by 2.63 mm in 5.2 months (P < 0.001). Significant lower incisors proclination as indicated by the increase in the angle of the axis of the most protruded lower incisor to the Mandibular plane (MP), Frankfort horizontal plane (FH) and NB Plane by 3.5°, 4.125°, 2.625° respectively (P < 0.001) as well as the increase in the distance from Ii to NB line by 1.688 mm. There was also a significant decrease in the amount of overbite by 2.813 mm (P < 0.001). Mandibular lower first molars vertical position was not significantly changed(0.625mm P > 0.05). As well as no significant change in the following measurements; lower facial height (0.5mm P > 0.05), posterior facial height (0.365mm P > 0.05) and the FMA angle (0.375mm P > 0.05). It was determined that the Connecticut intrusion arch was effective in intrusion of lower incisors.
2011
06
01
49
62
https://eos.journals.ekb.eg/article_78918_b6730d738c109951829e9ce5978c501a.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
Evaluation of spontaneous space closure after extraction of the first permanent molars
Mahasen
Taha
Objectives: The aims of this study were to evaluate changes in the position of the upper and lower premolars and second molars after first permanent molars "FPMs" extraction, compare the changes in the position of the upper and lower teeth, evaluate the over eruption of the upper FPMs in case of extraction of the lower one, and evaluate the midline shift in a unilateral extraction cases. Materials: Fifty female patients with age range 8-10 (mean age 8.9±0.9) years had one to four FPMs extracted due to severe caries. Each case was followed up for two years after extraction. Where the sample was ended by 43 patients only. The angular and millimetric changes were documented by panoramic radiographs. Over eruption and midline shift were observed clinically. Results: Both the upper and lower premolars showed distal tipping. However the lower tipped more than the upper. Also the lower second premolar showed more distal tipping than the lower first premolar .The lower second molar showed more mesial tipping than the upper one which moved more bodily. There were no over eruption of upper second molar or midline shift. Conclusion: Extraction of the FPMs severely affected by caries is a good treatment alternative. Favorable spontaneous space closure by adjacent teeth could be expected without any intervention, if it is extracted prior to the eruption of the second molar.
Extraction
panoramic radiographs
midline shift
2011
06
01
63
75
https://eos.journals.ekb.eg/article_78919_ef4dcc8b513f6201c2317c61110b0e97.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
Effect of bonding brackets by sulphated polyacrylic vs. Conventional acid etching on deciduous and permanent enamel
Shaza
Hammad
Abeer
Abdellatif
The aim of this study was to compare the shear bond strengths of metallic brackets bonded to deciduous and permanent enamel treated with crystalline growth solution (40% sulphated polyacrylic acid) and the adhesive remnants after debonding. Also, to verify the topographic difference of the treated deciduous and permanent enamel surface using Scanning Electron Microscope (SEM) compared with conventional acid-etching. Two sets of sixty freshly extracted deciduous and permanent teeth were collected. Each set was divided into 2 groups of 15 teeth each; groups I and II(deciduous teeth) and groups III and IV (permanent teeth). For groups I and III, 40% sulphated polyacrylic acid was applied and for groups II and IV, conventional acid-etching was used. Brackets were bonded, and the shear bond strength was measured using a universal testing instrument. The residual adhesive was examined using a stereomicroscope at 20 times magnification. The SEM topographic pattern of treated enamel was evaluated. Shear bond strengths of the brackets of the four groups were compared by Two-Way Analysis of Variance (ANOVA). T-test was done for inter-groups comparison. The least recorded shear bond strength was 12.65± 0.15 MPa in group I; the deciduous teeth treated withsulphated polyacrylic solution. Most of enamel surfaces treated with the sulphated polyacrylic acid were left clean with no or minimal adhesive remnants, after brackets debonding. The deciduous enamel treated with the sulphated polyacrylic acid revealed formation of less abundant crystals than that appeared on permanent teeth enamel as shown by the SEM. Thus it is concluded that, 40% sulphated polyacrylic acid can be used for bonding metallic brackets to deciduous and permanent teeth.
Crystalline growth
deciduous teeth
bonding
Shear bond strength
2011
06
01
77
91
https://eos.journals.ekb.eg/article_78920_1b5f7d2339c34b249a1f9639989a2d76.pdf
Egyptian Orthodontic Journal
1110-435X
1110-435X
2011
39
June 2011
The correlation between shape of the nose and the underlying hard tissue structures in adults: (cephalometric study)
R
Al-Majadi
A
Kaddah
Aim: To evaluate the relationship between the nose shape and the underlying hard structures. This study was performed in Orthodontic Department, Damascus University. Methods: The sample included 60 patients (48 male & 12 female) divided into 3 groups according to ANB ANGLE (20 class I, 20 class II, 20 class III). Seven skeletal parameters and 13 nasal parameters were measured on lateral Cephalograms by digital tracing) ORTHO-DAMASCUS 1996). Pearson correlation r was used for statistical analysis. Results: There was a correlation between skeletal and nasal parameters. The Facial hight, anteroposterior and vertical position of the maxilla and mandible were correlated with the nose shapeand length. In skeletal class I patients NMA, NLA were negatively correlated with the SNA, SNB (r = - 0.60, P < 0.05), (r = - 0.52, P<0. 05). A positive correlate between B angle with NMA, Nbone Lenght (r= 0.55, P<0.05, r= 0.52, P < 0.05 respectivly) negative correlated with Cconv. (r= - 0.47, P<0.05), positive correlation was found between SN-Go Me and NMA, NboneL (r = 0.54, P < 0.05,) (r = 0.54, P<0.05). In skeletal class II a negative correlated between SPP and NMA (r= -0.53, P<0.05) and positively correlated with SFC (r = 0.60 , P < 0.01) and negatively correlated between S.Go/ N.Me and DConv. (r = - 0.47, P<0.05).In skeletal class III a positively correlated between ANB and NLA (r = 0.61, P < 0.01) and positively correlated NS- SPP and NL (r = 0.57, P < 0.05) and negatively correlated between NS- SPP and NBA (r = - 0.46 , < 0.05). Conclusions: In long faces, the nose appears convex and increase in length with the nose tip inclined downward while in short or normal face the nose appears convex or straight with shorter nasal bone and a nasal tip inclined upward. The nasal tip moves with the anterior part of the maxilla.
2011
06
01
93
110
https://eos.journals.ekb.eg/article_78921_54e9dfc48765d3ef1f03ec16fe7119df.pdf