CIT Occlusion & Bite Registration in Implant Dentistry

Question 1

Why must occlusal forces on implant-supported restorations be managed more carefully than on natural teeth?

Accepted Answer

Implants lack a periodontal ligament, so they have no shock-absorbing mechanism or proprioceptive feedback

Answer

Natural teeth have a periodontal ligament (PDL) that acts as a shock absorber and contains proprioceptive nerve fibers that sense bite force. Osseointegrated implants have no PDL, so they transmit occlusal forces directly to the bone without attenuation and without the fine tactile feedback that natural teeth provide.

Question 2

Which occlusal scheme is generally preferred for a full-arch implant-supported fixed prosthesis to minimize lateral stress on implants?

Accepted Answer

Canine-guided (mutually protected) occlusion

Answer

Canine-guided or mutually protected occlusion is preferred for implant-supported restorations because it directs lateral excursive forces through the anterior teeth (or implants in that position), disoccluding the posterior implants and reducing the harmful lateral (non-axial) loading on posterior implants.

Question 3

During bite registration for an implant-supported crown, why is it important to have the patient bite lightly rather than at maximum force?

Accepted Answer

Maximum clenching compresses natural teeth in their sockets, potentially leading to an inaccurate registration that is too thin

Answer

Natural teeth can intrude 25–100 microns in their sockets under heavy occlusal load due to the PDL. If the patient bites hard during registration, the natural teeth are compressed; when they rebound, the bite record becomes too thin, and the final restoration may be fabricated in supraocclusion.

Question 4

A cantilever extension on an implant-supported bridge creates what type of potentially harmful force on the supporting implants?

Accepted Answer

Rotational and lever-arm forces that magnify stress at the implant-bone interface

Answer

A cantilever acts as a lever. Forces applied to the unsupported end are magnified at the fulcrum (the most distal implant), creating rotational moments and non-axial stress at the implant-bone interface. This significantly increases the risk of mechanical complications and bone loss around the supporting implants.

Question 5

Which bite registration material is most commonly used in contemporary implant dentistry due to its dimensional accuracy and rigidity after setting?

Accepted Answer

Polyvinyl siloxane (PVS) bite registration material

Answer

Polyvinyl siloxane (PVS) bite registration materials are preferred because they have excellent dimensional stability, minimal distortion after setting, are rigid enough to maintain the recorded position during model mounting, and do not deform during trimming. Alginate lacks stability; ZOE is messy and brittle; modeling compound has thermal limitations.

(CIT) Certified Implantology Technician Practice Test

(CIT) Certified Implantology Technician Practice Test

CIT Occlusion & Bite Registration in Implant Dentistry