Non anatomic Teeth are also called as Zero Degree or Cuspless teeth used in Complete dentures in Prosthodontics. Complete or Removable Partial Dentures are used in patients who have lost their natural teeth and want replacement. In normal cases, two types of teeth are used – Acrylic and Porcelain teeth which are decided depending on the requirement. Most commonly Cuspless teeth are made of Acrylic material.
Non Anatomic Teeth are Defined as: The Artificial teeth with occlusal surfaces which are not anatomically formed but which are designed to improve the function of mastication.
Cuspless teeth are Defined as: The artificial teeth which are fabricated without the cuspal prominences as seen in natural teeth to improve mastication and increase surface area.
Zero Degree teeth are Defined as: The artificial teeth which do not have any cuspal inclinations compared to the horizontal occlusal tooth surface.
The Indications of Non-Anatomic or Zero Degree or Cuspless Teeth:
- Flat ridges
- Knife edge ridges
- Large inter ridge space
- Milling type of chewing pattern with broad excrusions
- Where debilitation has reduced the patients co ordination needed to handle a cusped type of occlusion
- In patients with bruxism to decrease the force on basal tissue
- Patient with neuromuscular disorder where accurate jaw relations cannot be taken
- In case of highly resorbed ridges as they do not get locked or displace the denture during its function
Cuspless teeth are most commonly used in cases where loss of Vertical height is observed and attaining proper intercuspation is not possible, for this Acrylic teeth are used as they tend to grind depending on the patients habits and jaw relation. In cases like Bruxism where the patients tend to grind their teeth, cuspless teeth can help them in chewing and also prevent damage to the TMJ.