TY  - BOOK
AU  - Salama,Omar Ahmed El-sayed
AU  - Nassif,Essam
AU  - El-Sharaby,Fouad Aly
AU  - Aboalnaga,Amira
TI  - Alterations in the mechanical properties of  different brands of Nickel Titanium orthodontic  archwires following their exposure to the oral  environment in adult patients with moderate  crowding : : A Prospective Clinical Trial 
U1  - 617.643 23
PY  - 2021///
KW  - Orthodontics, Corrective
KW  - Orthodontics
N1  - Supervisors : Prof. Dr. Essam Nassif Professor in Orthodontics and Dentofacial Orthopedics Faculty of Dentistry Cairo University, Prof. Dr. Fouad El Sharaby Associate Professor in Orthodontics Faculty of Dentistry Cairo University, Dr. Amira Aboalnaga Lecturer in Orthodontics Faculty of Dentistry Cairo University; Thesis (M.Sc.)--Future University in Egypt, Faculty of Oral and Dental Medicine, Orthodantics Department , 2021; Includes bibliographical references (pages 127-148)
N2  - This present study was conducted to evaluate the change in mechanical 
properties of different brands of Nickel Titanium archwires following their 
exposure to oral environment.
The 117 wires were randomly divided into three groups (A), (B) and (C) 
according to brand of 0.016” round NiTi archwires; each of 39 archwires.
Group A: Dentaurum
Group B: American Orthodontics
Group C: IMD Orthodontics
Each group was further subdivided into 3 different subgroups (1), (2) and 
(3) according to intervention method, each of 13 archwires.
Subgroup 1 (IN VIVO): The wires were placed intraorally for 8-12 weeks
for leveling and alignment stage. 
Subgroup 2 (AS RECEIVED): The wires were measured as received from 
the manufacturer (negative control group).
Subgroup 3 (IN VITRO): The wires as received from the manufacturer 
were placed in artificial saliva for 8 weeks (positive control).
The results of the study were:
Condition, regardless of wire brand, had a statistically significant effect on 
mean plateau slope, resilience, elastic modulus.
As regards American Orthodontics wire, there was a statistically significant 
increase in mean Plateau slope after storage in artificial saliva as well as a 
statistically significant increase after usage in the patient’s mouth. While for 
Dentaurum and IMD Orthodontics wires, there was no statistically significant 
change in mean Plateau slope after storage in artificial saliva followed by a 
statistically significant increase after usage in the patient’s mouth
As regards American Orthodontics as well as IMD Orthodontics wires, there
was a statistically significant decrease in mean resilience after storage in artificial 
saliva as well as a statistically significant decrease after usage in the patient’s 
mouth. While for Dentaurum wires, there was a statistically significant increase 
in mean resilience after storage in artificial saliva followed by a statistically 
significant decrease after usage in the patient’s mouth. There was no statistically 
significant difference between resilience of new wires and wires used in the oral 
cavity.
As regards American Orthodontics as well as Dentaurum wires, there was 
no statistically significant change in mean modulus of elasticity after storage in 
artificial saliva followed by a statistically significant decrease after usage in the 
patient’s mouth. While for IMD Orthodontics wires, there was a statistically 
significant decrease in mean modulus of elasticity after storage in artificial saliva 
followed by non-statistically significant change after usage in the oral cavity. 
There was no permanent deformation present in any of the samples after 
comparing pre- and post-operative stereomicroscopic photographs.
In summary of the in-vitro studies, Dentaurum group showed desirable 
properties such as the release of light, continuous and almost constant forces 
during an extended period of activation.
Yet, the wire brand had no statistically significant effect on mean Little’s 
Index, so from the clinical perspective, all the wire brands performed the same in 
terms of resolution of crowding
UR  - http://repository.fue.edu.eg/xmlui/handle/123456789/6060
ER  -