Implants

Question 1

what is osseointegration

Answer 1

osseointegration is the direct functional and structural connection between a load bearing dental implant and living bone

Question 2

what are the 2 stages of osseointegration for dental implants

Answer 2

primary: (‘friction fit’) implant is anchored to bone via frictional forces provided between osteotomy and dental implant design features
secondary: process of functional connection between bone and a dental implant - living bone grows onto the surface of the implant

Question 3

tooth vs implant
- supra crestal fibres

Answer 3

tooth: more fibroblasts less collagen, collagen fibres perpendicular
implant: more collagen less fibroblasts, collagen fibres parallel

Question 4

tooth vs implant
- sub crestal

Answer 4

tooth: anchored to bone via periodontal complex, capable of physiological adaptation, resillient tissue attachment
implant: anchored to bone via direct functional contact, no physiological adaptation, rigid connection

Question 5

what materials are used for implants (3)

Answer 5

titanium
titanium-zirconium
ceramic (yttria stabilised)

Question 6

what are the different heights of implant and when are they used

Answer 6

bone height - aesthetic zones
tissue height - posterior

Question 7

what can be used to surface treat implants

Answer 7

sand blasting
acid etch
plasma spray

Question 8

pros and cons of rough surface implants

Answer 8

primary osseointegration is better with rough surface
however, if recession occurs, rough surface provides excellent surface for biofilm formation that patient cant clean thoroughly

Question 9

medical history considerations for implants

Answer 9

any conditions making patient unsuitable for long course of treatment
medications/ conditions affecting implant survival - bisphosphonates, poorly controlled diabetes

Question 10

social history considerations for implants

Answer 10

smokers have increased risk of implant failure and peri-implantitis

Question 11

dental history considerations for implants

Answer 11

attendance
oral hygiene
periodontal disease
anxiety
parafunctional habits

Question 12

risks associated with implants in the skeletally immature

Answer 12

relative infra occlusion
suboptimal aesthetics
occlusal disharmony

Question 13

discuss smile line relevant to implant placement

Answer 13

will impact on visibility of implant and prosthesis
high = >2mm ST on show
med = <2mm ST on show
low = >25% tooth covered

Question 14

discuss gingival phenotype and implant placement

Answer 14

thick gingival biotypes are less prone to recession and less prone to shine through than thin
most commonly differentiated by probe visibility

Question 15

discuss the length from bone crest to contact point regarding implant placement

Answer 15

distance from bone crest to adjacent contact point will determine height of papilla
<=5mm - low risk of poor aesthetics
5.5-6.5mm - medium
>=7mm - high

Question 16

why should implants be places at least 1.5mm away from adjacent teeth

Answer 16

lower risk of damage
lower risk of bone necrosis
lower risk of ST defects

Question 17

what are teh two methods of taking an impression for implants

Answer 17

open tray (screw in coping)
closed tray

Question 18

what can implant abutments be made from (3)

Answer 18

zirconia
titanium
alloys
gold

Question 19

pros and cons of screw retained abutments

Answer 19

pros: easier for repairs an maintenance, retrievable, less abutment height needed,
cons: technically demanding, more expensive

Question 20

pros and cons of cement retained abutments

Answer 20

pros: cement acts as a shock absorber, easier to fabricate, cheaper
cons: require sufficient abutment height, excess cement risk, often need cut for removal

Question 21

common causes of compromised soft tissue sites (3)

Answer 21

post extraction defects
trauma
hypodontia
periodontal disease
thin gingival biotype

Question 22

what are aesthetic outcomes of implant placement based on (4)

Answer 22

operator skill and experience
3D implant position
gingival biotype
distance from crestal bone to contact point
bone volume and morphology