ORIGINAL_ARTICLE
Dentoalveolar compensation in vertical skeletal dysplasia in an Egyptian sample
Introduction: The Dentoalveolar compensatory mechanism is the changes that occur in the dentoalveolar complex in cases of skeletal discrepancies (anteroposterior, vertical, transverse) in order to maintain functional occlusion. In a patient with a deep bite or an open bite coinciding with an extreme vertical lower face deficiency or excess, surgical approach that requires presurgical dental decompensation might be considered. Alternatively, simpler non-surgical treatment options involve dentoalveolar compensation. The determination of which option is suitable for a patient must be based on the feasibility of dentoalveolar compensation which in turn will depend on severity of skeletal discrepancy. An accurate estimation of the limits of dentoalveolar compensation is therefore a key to successful treatment. Aim of the study: To determine the extent of dentoalveolar compensation in various facial types and to investigate the influence of skeletal and dentoalveolar characteristics on overbites in long and short face individuals. Materials and methods: Lateral cephalometric X-rays from the department of Orthodontics, Alexandria University were evaluated till we got 90 lateral cephalometric X-rays of three equal groups: Long face, Average face and short face. 15 dentoalveolar measurements and 5 skeletal measurements were made on these Xrays. Comparison of linear, angular, area and ratio measurements were compared among the three study groups using ANOVA for normally distributed variables and Kruskal Wallis test for variables that were not normally distributed. Measurements that were significantly different among the three groups were further tested in comparison of pairs using Tukey post hoc test for normally distributed variables and Mann Whitney U test for variables that were not normally distributed. Comparison of overbite categories among the three groups was done using Wilcoxon signed ranks test. Non parametric correlation between study groups and categories of overbite was examined using Kendal tau b. Stepwise regression analysis was used to examine significant predictors of overbite in short, long faces separately and in the whole sample using all measured linear, area, angular and ratio measurements. Results: The results of this study showed that there were significant differences between the three groups in nine linear variables which were: ramus length, mandibular body length, anterior cranial base length, mandibular alveolar depth, mandibular and maxillary incisor alveolar and basal heights, mandibular and maxillary dentoalveolar heights and overbite. The prevalence study of different categories of overbite in the three groups showed that in the short face group about two thirds of the patients had deepbite while in the long face group only four cases had an openbite and more than half of the patients had normal or deepbite. The multiple regression analysis showed that that there were two powerful predictors of overbite in the short face group which were the ratio between the mandibular molar dentoalveolar height and mandibular incisor alveolar and basal height and the interincisal angle. In the long face group only one powerful predictor of overbite was determined which was the SN-Mandibular plane angle. Conclusions: The role of dentoalveolar compensatory mechanism in the establishment of the overbite had been shown, but still its effect is limited beyond certain limits. In the short face group the combined effect of both the mandibular molar and incisor alveolar heights play an important role in maintaining the overbite. An overbite of 3mm can be achieved if the ratio didn’t exceed 0.83.In the long face group the skeletal factors plays a more dominating role than dentoalveolar factors in controlling the overbite. Although the role of dentoalveolar compensation is more demonstrated in the long face group, its actual mechanism hadn’t been determined exactly. An overbite of 3mm can be achieved if the SN-Mandibular Plane angle didn’t exceed 39 degrees.
https://eos.journals.ekb.eg/article_78923_1cca26853f0e5eafe5ddee4a69ba2dd3.pdf
2011-12-01
1
27
10.21608/eos.2011.78923
Tarek
Yousry
1
Department of Orthodontics, Faculty of Dentistry, Alexandria University
LEAD_AUTHOR
Nadia
El-Harouni
dr_nadia2010@hotmail.com
2
Department of Orthodontics, Faculty of Dentistry, Alexandria University
AUTHOR
Essam
Abdullah
3
Department of Orthodontics, Faculty of Dentistry, Alexandria University
AUTHOR
ORIGINAL_ARTICLE
Effect of fluoride prophylactic agents on ceramic self ligating brackets
Purpose: To evaluate the effect of fluoride prophylactic agents on surface roughness (Ra) and fracture load (FL) of polycrystalline alumina bracket self ligating assembly. Materials and Methods: Fifty maxillary central incisors self ligation polycrystalline alumina brackets (Damon Clear) were used in this study. Brackets were divided into five equal groups. In group 1; specimens were immersed in distilled water (dH2O) for 8 hours. In group 2; specimens were immersed in 1.1% sodium fluoride solution (NaF) for 4 hours then in dH2O for another 4 hours. In group 3; specimens were immersed in NaF solution for 8 hours. In groups 4 and 5 the same procedures were followed as in group 2 and 3 respectively but 1.1% acidulated phosphate fluoride solution (APF) was used instead of NaF. Finally, Ra and FL of the self ligating assembly of the brackets were assessed. The data was subjected to analysis of variance (ANOVA) and Tukey post hoc tests. Results: Utilization of APF for 8 hours provided a significantly higher Ra value than the other studied protocols (P < .05). The later showed no significant differences between them (P > .05). No significant difference was found in FL among different studied groups (P >.05) except between brackets stored in dH2O and those stored in APF for 8 hours (P < .05). Conclusion: APF should not be used for long periods with polycrystalline ceramic self ligating bracket because it adversely affects Ra and FL of the ligature assembly. On the other hand, NaF could be used safely.
https://eos.journals.ekb.eg/article_78924_c68c515608f48512a5e6c3fb19caffda.pdf
2011-12-01
29
39
10.21608/eos.2011.78924
Yasser
Abdelnaby
1
Department of Orthodontics, Faculty of Dentistry, Mansoura University
LEAD_AUTHOR
Mahasen
Taha
2
Department of Orthodontics, Faculty of Dentistry, Mansoura University
AUTHOR
ORIGINAL_ARTICLE
Maxillary midline diastema among Saudi schoolchildren in Riyadh: prevalence and some related etiological factors
The aim of this study is to investigate the maxillary midline diastema in Saudi schoolchildren in Riyadh; particularly prevalence and some likely related etiological factors with regard to gender and age. The present epidemiologic study was undertaken in intermediate schools of Riyadh City. A total of 1,825 Saudi schoolchildren (1007 boys and 818 girls) aged 12 to 16 years were randomly selected. Clinical examination was carried out in the schools within the students’ classrooms by two experienced examiners using simple plain mouth mirror, small light source and stainless steel ruler. Students with a history of orthodontic treatment or prosthodontic restorations in the upper anterior teeth and periodontal disease were not included in the sample. An especially composed chart was used to record demographic dataand inter arch parameters. All data were analyzed using SPSS program and simple descriptive statistics with regard to boys and girls. Results revealed the prevalence of maxillary midline diastema was 394 (22%) out of 1825 students examined. A similar figure, though slightly greater prevalence of maxillary midline diastema in boys (22%) than in girls (21%). The highest prevalence was observed in 13 years age group (7.7%). The width of maxillary midline diastema ranged between 1-2 millimeters demonstrated (79.2%) of total sample, greater in boys (91%) than girls (64.4%), and (100%) in 16 years age group. The maxillary midline diastema width of 3-4 millimeters occurred more in girls (35%) than boys (9%), and in 12 years age group (35.5%) than other age groups with decrease up to 16 years of age. Among the observed etiological factors in both sexes and different age groups, spacing in anterior region (35.5%) was the most frequent etiological factor associated with maxillary midline diastema. Followed by increased ovejet (15.7%), missing tooth (11%), while the frequency of deep bite and anterior open bite was 6.3% and 5.8% respectively. It was concluded that maxillary midline diastema is a common occurrence in Saudi children associated with multifactorial etiology. Consideration of etiological factors and individual treatment planning are essential in the proper management of maxillary midline diastema.
https://eos.journals.ekb.eg/article_78925_391b93b9adedf787ae8ce473d3029cbc.pdf
2011-12-01
41
55
10.21608/eos.2011.78925
diastema
malocclousion
children
maxillary
midline
Sahar
Albarakati
1
Department of Pediatric Dentistry and Orthodontics College of Dentistry, King Saud University, Saudi Arabia
LEAD_AUTHOR
Yousef
Al-Dlaigan
2
Department of Pediatric Dentistry and Orthodontics College of Dentistry, King Saud University, Saudi Arabia
AUTHOR
ORIGINAL_ARTICLE
The comparison of soft tissue profile after treatment with fixed functional appliance, with dental anchorage and skeletal anchorage systems
Skeletal Class II due to mandibular retrusion is one of the major orthodontic problems. Nowadays, a great variety of non-compliance appliances are available to advance the mandible forwards. The study was carried out on 19 Class II Div 1 patients who were divided into two groups. The first group was treated using Twin Force Bite Corrector (TFBC) while the second Group was treated with Twin Force Bite Corrector with skeletal anchorage using mini-plates. Pre-treatment and 3months post-treatment cephalograms were obtained. The changes in the soft tissue profile were inspected. The results showed significant changes in soft tissue measurements after placing TFBC. In addition, there was a significant advancement in soft tissue pogonion in the second group due to the more mandibular advancement.
https://eos.journals.ekb.eg/article_78926_00195d3826cf8a154050912704b1af49.pdf
2011-12-01
57
75
10.21608/eos.2011.78926
soft tissue profile
fixed functional appliances
skeletal anchorage
Wael
Refai
1
Department of Orthodontics, Faculty of Dentistry, Minia University
LEAD_AUTHOR
ORIGINAL_ARTICLE
Comparing different porcelain surface polishing techniques after orthodontic brackets debonding
Objectives: The present study was designed to investigate different polishing techniques used to restore feldspathic porcelain surface regarding surface roughness after debonding of orthodontic brackets. Methods: Metal discs of 1 cm diameter and 1 mm thickness (n=85) were prepared from Wiron 99 non-precious alloy (BEGO Bremer Goldschägerei with Herbst GmbH& Co. Bremen. Germany). The discs were veneered from one side by 1 mm thickness Vita VMK Master feldspathic porcelain (Vita zhan fabric H. Rauter GmbH & Co. KG. Germany). Five of these intact samples composed the control group (C). Orthodontic metal brackets were bonded at the center of each of the remaining discs (3M, Unitek),and then discs were water stored for 30 days before rebounding. Brackets were debonded using bracket removing pliers, and resin was removed with a sharp chisel. The prepared specimens (n=80) were divided into 4 groups (n=20) according to the surface treatment they were to receive: (G1): using (Shofu, USA) porcelain veneer jkit, (G2): using (Ultradent, USA) porcelain finishing kit, (G3): using (Sof-lex 3M, USA) porcelain polishing kit, and (G4): no surface treatment. The surface roughness (Ra) was evaluated quantitatively using USB Digital microscope with a built-in camera (Scope Capture Digital Microscope, Guangdong, China). WSxM software was used to calculate root mean square (RMS) of the average height of every specimen expressed in (μm) in each group including control samples. Data was analyzed with 2-way ANOVA followed by student’s t test (p<0.05). Results: The polishing techniques affected surface roughness significantly (P<0.001), with significant higher Ra values than the glazed baseline porcelain. The surface roughness values were not statistically different among the polishing groups (P>0.05). Conclusion: The results of this study indicated that the tested polishing techniques improved the surface roughness greatly, however, were not able to reestablish the original glazed porcelain smoothness.
https://eos.journals.ekb.eg/article_78927_c2de9e88da78185e34c05a1e78aed0ad.pdf
2011-12-01
77
90
10.21608/eos.2011.78927
Hany
Eid
1
Department of Orthodontics, Faculty of Dentistry, Misr University for Science and Technology, 6th of October city, Egypt
LEAD_AUTHOR
Nasser
Hussein
2
Department of Fixed Prosthodontics, Faculty of Dentistry, Misr University for Science and Technology, 6th of October city, Egypt
AUTHOR
ORIGINAL_ARTICLE
Assessment of four cephalometric measurements utilized in evaluation of the maxillary position in anteroposterior direction
Aim of the work: The present study was conducted to assess four cephalometric measurements utilized in evaluation of the maxillary position in the anteroposterior direction. The assessment was depending on normality parameters of each measurement and the correlation between them. Material and Method: Lateral cephalometric radiographs of forty Egyptian adults (20 males and 20 females) with an age range from 19-22 years were selected for this purpose. All had accepted normal occlusions, normal skeletal relationship and balanced profiles. The radiographs were traced and the following measurements were done; SNA angle, A point to nasion perpendicular distance, condylion to A point distance, and basion to A point distance. Statistical analyses were performed to asses these four measurements. Results: The results revealed that Ba-A was the best measurement satisfied the normal distribution assumption. Ba-A and SNA angle had the highest symmetrical distribution. There were significant correlation between all measurements except between Co-A and either SNA and A-Np. In addition, there were significant differences between males and females regarding Co-Aand Ba-A measurements. Conclusion: In assessing the maxillary growth, Ba-A measurement satisfied the normal and symmetrical distribution assumption better than the other studied measurements. The males norms of Co-A and Ba-A measurements should not be used for females.
https://eos.journals.ekb.eg/article_78928_3a742c4503a36657a48c8eb0e53121cd.pdf
2011-12-01
91
102
10.21608/eos.2011.78928
Yasser
Abdelnaby
1
Department of Orthodontics, Faculty of Dentistry, Mansoura University
LEAD_AUTHOR
Mahasen
Taha
2
Department of Orthodontics, Faculty of Dentistry, Mansoura University
AUTHOR