Which of the following is not true about ultrasonic:
A. oscillates between 1500 to 3000Hz ***
B. release energy known as cavitation
C. acoustic steaming
D. implosion
Ultrasonic No. cycle
1. Magnutorestrictive 25000-40000 rpm
2. Pezoelectrive 60,000-80,000 rpm
X-Ray important informations:
Submentovertex: for diagnosis zygomatic arches
Occipitomental: Best radiograph for fracture of the middle third of face (Nasoethmoid f)
Reverse town's: for condyle & subcondylar region
Water's x-ray: view for maxillary sinus and midface fracture.
Panorama: full mouth examination
Lateral cephalometric: for orthodontic
Post. Anterior "PA" view: for vertical favourable and unfavourable fracture of the angle
Lateral Oblique 30: for horizontal favourable and unfavourable fracture of the angle
Lateral Oblique 15: for Ramus and body of the mandible
Bitewing x-ray: for caries (interproximal) in post. Teeth
MRI: for TMJ & is very good for soft tissue (therefore for TMF as disc is soft tissue)
CT scan: is for good for hard structures.