Soghra Yassaei; Farzaneh Eslami; Roya Ghafouri fard
Abstract
Aim: Considering the importance of stability on the orthodontic treatment outcomes, the instability may cause dentoskeletal and soft tissue changes in patients after the treatment. The aim of this study was to evaluate dentoskeletal and facial soft tissue relapse in class II patients whom have been treated ...
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Aim: Considering the importance of stability on the orthodontic treatment outcomes, the instability may cause dentoskeletal and soft tissue changes in patients after the treatment. The aim of this study was to evaluate dentoskeletal and facial soft tissue relapse in class II patients whom have been treated with functional appliances. Materials and Methods: 23 patients with Class II Division 1 malocclusion who had received treatment with Farmand functional appliance and had at least two years of post treatment follow up, were evaluated using cephalometric analysis for dentoskeletal and soft tissue changes. The lateral cephalometric radiographs of the patients immediately after the treatment (T1) and two years follow up (T2) were traced and statistical analysis was performed to obtain the amount of occurred relapse between T1 and T2.Results: The mean decrease of ANB angle between T1 and T2 was 0.73 º, which was not statistically significant. Overall, the mean changes of skeletal and dental variables (FMA, GOGN-SN, U1 to SN, U1 to FH and IMPA) in T1 and T2 were not statistically significant. For the soft tissue variables, the mean increase of the nasolabial and mentolabial angle in T1 and T2 were not significant. The mean changes of Z and H angles in T1 and T2 were 0.53º and 0.63 º, which were not statistically significant. Conclusion: Dentoskeletal and soft tissue facial changes that occurred during treatment with Farmand functional appliance remained stable at least 2 years after treatment.
Seyed Mohammad Hosseinikhah; Zahra Ebrahimi Nik; Soghra Yassaei; Seyed Morteza Saadat Mostafavi; F. Faghir
Abstract
Background and aim: There are no strict criteria in determining the need for orthodontic treatment and dentists often have different opinion on assessing the orthodontic treatment needs. Making an appropriate estimation of the need and demand for orthodontic treatments is necessary to organize and provide ...
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Background and aim: There are no strict criteria in determining the need for orthodontic treatment and dentists often have different opinion on assessing the orthodontic treatment needs. Making an appropriate estimation of the need and demand for orthodontic treatments is necessary to organize and provide meaningful orthodontic services. In this study, the orthodontic treatment needs were evaluated in highschool boys of Yazd.Materials and methods: 420 students who were studying in 14 different high schools were randomly selected. All participants were examined under normal white light and DHC(dental health component) ruler. To assess the orthodontic treatment needs, the dental health component of IOTN index was used. The data were analyzed by Chi-square test and p-value was 0.05.Results: Measurements showed that 44.8% of students scored 1, 15.1% scored 2, 13.6% scored 3, 15.3% scored 4 and 10.7% scored 5 in DHC records. The most frequent malocclusions observed in this study population were contact point displacement (27.3%), crossbite (13.3%), hypodontia (12.8%) and increased overjet (9.3%).Conclusion: Based on the results, approximately one fourth of participants had definite need for orthodontic treatments (IOTN Grades 4 and 5) which is a warning sign. More studies are needed to be done on different populations of the country to make the governors able for organizing oral health programs and providing beneficial dental insurance.
Abdolrahim Davari; Soghra Yassaei; Mahdjoube Goldani Moghadam; H. Zoghi
Abstract
Aim: The objective of this study was to determine the effect of thermocycling on shear bond strengths (SBSs) of a light cured compositeafterdifferent thermal cycles.Materials and methods: 80 Bovine incisors were randomly divided into 4 groups of 20 teeth. Each teeth were etched with 37% phosphoric acid ...
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Aim: The objective of this study was to determine the effect of thermocycling on shear bond strengths (SBSs) of a light cured compositeafterdifferent thermal cycles.Materials and methods: 80 Bovine incisors were randomly divided into 4 groups of 20 teeth. Each teeth were etched with 37% phosphoric acid and brackets were bonded using a light cured composite (Resilience). Thermocycling was done between 5° C and 55° C for 500, 3000 and 6000 cycles in group 2,3 and 4 respectively. Teeth in group1 (control group) were not being thermocycled. The SBS values were measured by means of Dartec testing machine.
Results: The results showed significantly higher SBS values for the control group compared to test groups (2-3 and 4). No significant different was observed between test groups.
Conclusion: Thermal changes during thermocycling significantly reduce the mean SBS of conventional etch and rinse adhesive system (Resilience), but SBS in 500, 300 and 6000 cycles had no significant difference. Clinical significance: Alteration in values of shear bond strengths under thermocycling would be representative of expected behavior of orthodontic brackets in clinical situations.