Dental implants are medical devices that replace missing teeth by anchoring a new tooth structure directly into the jawbone. Unlike a removable denture, an implant is designed to carry chewing forces through the bone in a way that resembles a natural tooth root. This makes implants important for restoring bite function, speech, appearance, and long-term jaw health.
The main parts are a ceramic crown, an abutment, and a titanium implant post with threads.
Key Facts
- A dental implant has three main device parts: crown, abutment, and implant post.
- Osseointegration is the process in which living bone grows tightly around the implant surface.
- Titanium is widely used because it is strong, corrosion resistant, and biocompatible.
- Pressure = Force / Area, so spreading chewing force over more bone area can reduce local stress.
- Stress = F / A, where F is load and A is the contact or cross-sectional area carrying the load.
- Implant stability depends on bone quality, implant geometry, thread design, healing time, and hygiene.
Vocabulary
- Dental implant
- A dental implant is an artificial tooth-root device placed in the jawbone to support a replacement tooth.
- Osseointegration
- Osseointegration is the direct bonding of living bone to the surface of an implant.
- Abutment
- An abutment is the connector piece between the implant post and the visible crown.
- Crown
- A crown is the artificial tooth-shaped cap that restores the visible chewing surface.
- Biocompatibility
- Biocompatibility is the ability of a material to function in the body without causing harmful reactions.
Common Mistakes to Avoid
- Thinking the crown is the implant, but the implant is the root-like post inside the bone and the crown is only the visible replacement tooth.
- Assuming the implant works immediately at full strength, but bone healing and osseointegration usually require time before heavy chewing loads are safe.
- Ignoring force direction, but sideways forces can create larger bending stresses than straight downward chewing forces.
- Treating titanium as biologically invisible, but its success depends on surface chemistry, cleanliness, bone response, and protection from infection.
Practice Questions
- 1 A person applies a chewing force of 180 N on an implant crown. If the effective load-bearing area is 30 mm^2, what is the average stress in N/mm^2?
- 2 An implant post has a circular cross-section with radius 2.0 mm. Calculate its cross-sectional area using A = pi r^2, then find the stress if it carries a 200 N vertical load.
- 3 Explain why threaded titanium posts can improve implant stability compared with a smooth post of the same diameter.