3 Implant Final Exam Review: Focus on Biomechanics and Occlusion Concepts

25-100

natural teeth move apically about _______μm under load

3-5

•implant moves about ______μm under load

lower incisors

Almost all natural roots are wider in diameter than implants, except _____

similar

Natural teeth have elastic modulus _____ to bone

5 to 10 times

Implants have elastic modulus _____ to bone

4 to 5

for an implant, Occlusal awareness is ____ times less than a natural tooth

reduced

Although patients with dental implants are able to bite and chew, the fine motor control that was present with vital teeth is ______

20 microns

What is the occlusal thickness perception for tooth to tooth:

48 microns

What is the occlusal thickness perception for tooth to implant:

64 microns

What is the occlusal thickness perception for implant to implant:

8 microns

What is the occlusal thickness of shimstock:

25 microns

What is the occlusal thickness of accufilm articulating paper:

63 microns

What is the occlusal thickness of ardent articulating (fullarch) paper:

cortical

the bone surrounding a tooth is _____

trabecular

the bone surrounding an implant is _____

4

In patients with bruxism, the duration of tooth contact /24hrs is ____ hours per day

300 lbs/sq. in.

In patients with bruxism, the magnitude of force is up to _____

vertical and hotizontal

In patients with bruxism, the direction of applied force is _____

isometric

In patients with bruxism, the type of muscle contraction is _________

Neuromuscular protective mechanism reduced

In patients with bruxism, the Proprioceptive influence is ______

- coronal restoration

- abutment/framework

- abutment screw

- implant platform

- internal walls of implant-abutment connection

- implant body

- bone

how do forces travel on an implant?

implant threads

force applied axially to the implant is redirected by the _______

Mechano-transduction

__________ is the process of load transformation into biological and biochemical reactions

magnitude

The _______ of the forces acting on the bone‐implant interface, the direction of the forces, and the period these forces are applied, will determine the maintenance of the osseointegration equilibrium or its breakdown

greater

The stiffness of oral implants of titanium or its alloys is

several times _____ than that of cortical bone

compressive

bone is strongest under ______ forces

tensile

bone becomes weaker under ______ forces

shear

bone becomes EVEN weaker under ______ forces

true

t/f: Marginal bone loss around oral implants is common during the first year of function

• reflection of the periosteum during surgery

• preparation of the implant bed

• occlusal overload

• the configuration of the coronal part of the implant (implant

neck)

• microgap between the abutment and implant/ bacterial

invasion

• biological width

What are some some CLINICAL factors that contribute to

marginal bone loss:

thread major diameter - thread minor diameter

how do you measure thread depth?

Crest Module (implant neck)le

- Transosteal region of the implant body

- Characterized as a region of highly concentrated

mechanical stress and bone loss

narrowing

Implants with ________ cross sections at the top, create more

favorable load transfer characteristics for single-tooth implants...

engaging

single implant restorations MUST have a _______ conical connection

non-engaging

multiunit implant restorations can have a _______ conical connection

platform switching

-a concept of using a dental implant abutment of

smaller diameter than the dental implant

• longitudinal radiographic observation has

demonstrated decreased vertical bone

resorption

smaller

platform switching is when the abutment is _____ diameter than the diameter of the implant

produces a surface on the top of the

implant collar, onto which soft tissue can grow:

• Soft tissue will not only be on the lateral surface of the implant,

but also on this top surface

• This increases volume of soft tissue

Why does platform switching work?

0Better blood supply provided by this increased soft tissue volume

leads to better soft and hard tissue stability.

• Physiological stresses on the gingiva e.g. when chewing will not

lead to a loosening of the gingiva at the vertical implant surface,

as the gingiva also adheres to the top surface of the implant

collar.

• The absence of these micro-movements is said to reduce the

bone resorption.

• Tighter soft tissue seal.

What are the benefits of platform switching?

5.3

incidence of abutments screw loosening _____% in the first year after loading and 5.8%-12.7% after the 5-year follow-up

increase

increased micro-motion and micro-gap of the implant-abutment interface may _____ micro-leakage at the implant-abutment interface and causing biological complications

true

t/f: abutment screw loosening may progress into abutment screw fracture and can lead to implant fracture

preload

• an engineering term used in

dentistry to describe the degree

of tightness or clamping force of a

screw, usually in implant

prosthodontics

• the tension created in a screw,

especially the threads, when

tightened

torque

preload is positively correlated with the value of the screw tightening _____

false

t/f: larger tightening always means better for the implant

true

t/f: when the preload exceeds the yield limit of

the abutment screw's material, the screw is

permanently deformed and loses its

function, thereby loosening or even

fracturing screw

Newtoncentimeters (Ncm)

• The unit of measurement for implant torque is _____

Impression copings, healing abutments

Which parts of the implant are NEVER torqued?

better

the internal connection might have ______ resistance to torque loss and screw loosening than external connection

true

t/f: the original components are more stable than the nonoriginal ones in general

cantilevers

ID this system

cantilevers

lead to stress concentration and increase the

risk of screw loosening:

false

t/f: Connecting implants and natural teeth is recommended

greater

Angled forces are associated with ______ crestal bone stresses

longer

the______ the cantilever, the greater the load magnification and the more stress is concentrated in the bone (anchoring the neck of the implant adjacent to the cantilever

narrow

A _______ occlusal table

-require less force to penetrate into

food during mastication

• facilitate daily home care, since they

are not overcontoured

• more realistic when resorption

pattern of bone is considered

single

a _______ contact is centered over the long access of the implant, is preferred.

increase

______ in the numbers of implants can result in a more favorable load distribution in the bone, provided that they are adequately spaced and located so as to evenly

distribute forces both to the bone and to each other

better

Nonlinear implant alignments resist lateral forces _____ and, theoretically, this may be of benefit in patients with lateralized chewing cycles that lack anterior

guidance.

0.9 and 2.2

In cases of reduced vertical bone dimensions and

increased interocclusal space, the use of single tooth

restorations with crown-to-implant ratio in

between _______ is NOT EXPECTED to

increase the failure rate and

• the patient shows signs of parafunctional activities.

• the quality of bone anchoring the implants is questionable

(type IV bone or grafted sites).

• implants are misangled, that is, not perpendicular to the plane of occlusion.

• relatively short implants (less than 10 mm in length) have been employed.

• the patient presents with or is to be restored with group function.

• the restoration is in the maxillary posterior quadrant

Splinting of the implants supporting posterior restorations is recommended, when:

• implants of 10mm in length or longer are placed.

• the quality of bone is good.

• implants are placed with perfect angulation (perpendicular to

the plane of occlusion).

• there is no parafunctional activity.

• anterior guidance is provided by the anterior dentition.

Nonsplinted designs are used in posterior

quadrants only in the mandible and only under the following circumstances:

mandible

Nonsplinted designs are used in posterior quadrants only in the ______

anterior canine

The implant restorations were designed to be independent

of one another because the patient presented with ideal

______-protected guidance.

closely as possible

for Single Implant Prosthesis, Implant diameter Correspond as ________ to the lost tooth

Perpendicular

for Single Implant Prosthesis, Implant angulation is ______ to the curves of Spee and Wilson

narrow

for Single Implant Prosthesis, the Occusal table should be ______ to minimize nonaxial forces

minimal

for Single Implant Prosthesis, Cusp height/ angles should be _____

In central fossa, larger flat contact area (1,5-2

mm), avoid contacts at marginal ridges and

inclined planes

for Single Implant Prosthesis, MIP contacts should be:

Increased- to dissipate occlusal forces

for Single Implant Prosthesis, proximal contacts should be ______

Bilateral balanced

Occlusal Recommendations for OVERDENTURES:

• ________ occlusion using lingualized occlusion

lingualized

Occlusal Recommendations for OVERDENTURES:

• bilateral balances occlusion using _______ occlusion

Monoplane occlusion

Occlusal Recommendations for OVERDENTURES:

• ________ on severely resorbed ridges