Trauma from Occlusion: Dental Implants Flashcards
What are the 2 types of trauma from occlusion?
- Tremendous amount of force
2. Support of tooth is compromised causing normal forces to be traumatic
What are some examples of tremendous amounts of forces leading to trauma from occlusion in dental implants
- Bruxing
2. High restorations
What is the relationship between force and physiologic limits of the tooth in regard to trauma from occlusion?
Trauma from occlusion occurs when the forces on the tooth are GREATER than the physiologic limits allowed by the tooth
Describe attachment of a natural tooth vs an implant
- Natural Tooth: PDL attachment apparatus
- Dental Implant: Direct bone-implant surface mechanical binding (osseointegration) – NO PDL buffer zone, NO ‘give”
Describe the ability to adapt with a natural tooth vs a dental implant
- Natural tooth: can “adapt” to heavy forces
- Implant: Continuous bone remodeling at bone-implant surface interface – no mobility during remodeling
Describe physiological vs pathological mobility in a tooth vs an implant
Tooth: Tooth mobility can be a physiological OR a pathological phenomenon
Implant: Implant mobility is ALWAYS pathological, never physiological
Can you tie an FPD between a tooth and an implant? Why or why not?
No! Because the tooth has a different level of mobility than the implant. This would lead to bone damage and/or fracture.
(you can tie b/t 2 implants tho)
What 3 structures are in contact in a natural tooth socket?
Bone, PDL, and cementum
Describe dental implant osseointegration
Direct contact between living bone and the implant surface
Where is the only place that you could find very very very minor movement of an implant in health
within trabecular bone – super tiny – if asked, say implants are immobile!!!
What are the 3 factors that determine osseointegration?
- Primary stability
- Healing at the interface
- Functional implant loading
Describe healing at the interface with dental implants, and max vs mand times
- Bone formation and early remodeling occurs during healing at the interface following implantation
- Max early remodeling = 3 mos
- Mand early remodeling = 6 mos
What is primary stability of a dental implant and what does it depend on?
- Primary stability is the stability of the implant at the time of the placement (mechanical interlocking mechanism b/t a screw and bone surface)
- Depends on bone density and implant fixture design
What are the 3 types of functional loading of the implant?
- Immediate loading (at time of placement)
- Early loading (before conventional healing time, ~6wks)
- Late loading (following 3-6 mos, depending on location)
What are the 4 restorative designs of dental implants?
- Single tooth restoration
- Multiple unit fixed-type restoration (splinted)
- Full mouth fixed type implant supported restoration
- Full mouth removable type implant supported restoration
What are the 5 major consequences of having an implant in high occlusion?
- Porcelain fracture
- Implant to abutment (screw loosening or fracture)
- Implant fixture fracture
- Increasing mobility of adjacent teeth
- Eruption/malocclusion/intrusion, etc of adjacent teeth (observed following functional loading of the dental implant)
Describe the effect of extraction on sensory nerves of the PDL
Sensory nerves to supply the PDL are GONE following extraction
What happens to the inferior nerve following extraction?
Myelinated fiber content of the inferior nerve is reduced by 20%
Where might an implant get some sensory information?
Presence and potential function of sensory nerve fibers in the BONE and PERI-IMPLANT environment
Why does the implant have a small amount of proprioception?
There is a gradual increase in the FREE nerve endings close to the implant-bone interface during healing
How do implants maintain mechanical sensation after the extraction has already occurred?
Mechanical sensation comes from existing mechanoreceptors within the periodontium.
Describe sensory feedback pathways in periodontium
Sensory feedback thru receptors localized within pdl (viscoelasticity) and with bone (elasticity) are necessary for fine tuning jaw and limb motor control – needed for tactile sensibility and thickness discrimination
How do “tactile sensibility” and “thickness discrimination” vary between natural teeth and implants?
Natural teeth: detection threshold of 20 um thickness and 1-2 g upon tooth loading
Implants: detection thresholds of 50-100 um thickness and 50-100 g upon loading (100% less efficient at detecting thickness and pressure)
What are the 2 types of implant studies?
- Animal models
2. finite element analysis (FEA)
What are the 3 types of forces on an implant?
- Static forces
- Functional forces
- Excessive forces
What are static forces?
Constant forces applied as in orthodontic movement
What are functional forces?
Expected intermittent multidirectional forces that would occur when a tooth/implant is in normal function
What are excessive forces?
Forces that well exceed those of teeth/implants in function, such as cantilevered implants
What are the restrictions between implants and orthodontics?
Cannot do ortho ON implants because need PDL in order to achieve orthodontic movements….will result in HYALINIZATION. Do ortho first!
What 4 factors does loading time depend on for an implant?
- Primary stability of the implant
- Implant design (thread size)
- Restorative design
- Presence/absence of risk factors
What are some risk factors that can effect loading time?
Diabetes, smoking, bone resorption
Functional and well controlled loading may increase _____, but 100% bone-implant surface contact is _______.
Functional and well controlled loading may increase BONE TO IMPLANT CONTACT, but 100% bone-implant surface contact is NOT POSSIBLE
Occlusal trauma is a _______ etiological factor for periodontal disease, but it can be a ______ etiological factor for peri-implant disease
Occlusal trauma in perio disease = Secondary factor
“ “ in peri-implant disease = PRIMARY factor
What is the only direction of force that an implant can accept? What happens if this is not respected?
Axial (vertical) loading only….otherwise get peri-implant bone loss, bacterial ingress, infection and retrograde peri-implantitis
What are the extra steps you must take if placing an implant in a patient who bruxes?
- Provide a mouthguard
- Use longer and wider dental implants
- Surround with thick bone for support
What is the concept behind “all-on-4”
Hybrid dentures with 2 straight implants and 2 implants at an angle in the intermentalous region so that posterior teeth can be soundly cantilevered.
What is the #1 requirement of “all-on-4” implants (and all implants really)
MUST PLACE IN GOOD QUALITY BONE – there will be bone resorption, huge amounts in particular with all-on-4.
What are the 3 most common problems as far as the physical implant is concerned when there is high occlusion?
- Chipping
- Loosening
- Implant fracture
