implants Flashcards
osseointegration
A direct functional and structural connection between a load bearing dental implant and living (organised) bone.
A soft tissue cuff similar to gingivae develops around the Implant
2 stages in osseointegration
Primary osseointegration- Implant is anchored in bone due to frictional forces provided between osteotomy and dental implant design features
Secondary osseointegration- The process of a functional connection between bone and a dental implant. Living bone grows onto the surface of a dental implant
healing following implant insertion
- Immediately after implant installation
- Granulation tissue in wound chamber (days)
- Immature (woven bone) (weeks)
- Mature lamellar bone (months)
- Collagen orientation present at 4/52, mature tissue attachment 6-8/52
tooth
organisation of tissue supra and sub crestal
Supra-crestal soft tissue
* More fibroblasts
* Less collagen
* Collagen fibers orientated perpendicular to root surface
Sub-crestal
* Tooth anchored to bone by periodontal complex (bone/PDL/cementum)
* Capable of physiologic adaption
* “Resilient” tissue attachment
implant
organisation of tissue supra and sub crestal
Supra-crestal soft tissue
* More collagen
* Less fibroblasts
* Collagen fibers orientated parallel to implant crown
Sub-crestal
* Implant anchored to bone by direct functional contact
* No Physiologic adaption present
* Rigid connection
material options for dental implants
Titanium (Ti)
- Commercially pure type 4 titanium (most implants)
- > 85% to produce titanium dioxide
titanium Zirconium (Ti-Zr)
- 85% Ti, 15% Zi
- Increased strength compared to Ti
Ceramic Implant (Y-TZP)
- Yittra stabalised zirconia
- Marketed as a ceramic implant
- Non-metallic coloured (prevent shine through)
- High survival at 1 and 2 years (Roehling 2018
feature of tissue level implant
Polished collar – above gum line (interface between implant and abutment at tissue level compared to bone level)
implant design features
No significant effect on implant survival or success on different implant designs (Jolkstad 2018)
Bone level/tissue level
- Bone level commonly used in aesthetic zone
- More space to design emergence profile etc
Tissue level used posteriorly
Tapered/parallel
- Tapered may provide increased primary stability in immediate placement
- Tapered may be used where there is root convergence apically
how to decide on implant length and diameter
Implants come in a variety of lengths and diameters (3-4.5mm diameter)
These may be selected due to:
- Site
- Indication
- Local anatomy
High survival of narrow diameter implants (Scheignitz 2018)
High survival of short <10mm implants (Telleman 2011)
implants suface tx
machined/turned
roughness - smooth, mild, moderately, rough
to allow reparative osteoblasts and cytes to grow into the implant to provide a good connection
- sand blasting
- acid etch
- plasma spray
what is the purpose of a dental implant
Replace missing teeth
- Functionally
- Aesthetically
- Psychologically?
Primary aims of dental implant treatment
- Replace missing teeth with aesthetic, functional and predictable restoration
- Low rate of complications during healing and maintenance period
- Long term stability
pt assessment for dental implants
areas to asses
Patient Level
- Presenting complaint
- Motivation
- Medical history
- Dental history
- Social History
- Age/skeletal maturity
Mouth level
- Extra-oral
- Intra-oral
Site Level
- bone quantity and quality
- periodontal status of tooth
- endodontic status of tooth
- prosthetic value of tooth
pt presenting complaint
considearations
will implant solve this issue
are their expectations realistic - esp aesthetics
MHx considerations
anything that render them unsuitable for prolonged course of tx
- ASA class;
- haematological issues
anything that may effect survival rate of implants
- medications - SSRIs, PPIs, Bisphosphonates, steroids
- radiotherapy
- poorly controlled diabetes
- CVD - increased survival!
SHx considerations
smoking
- inc risk implant failure and peri-implantitis in smokers
- dose dependent relationship
- affects - vascularity, fibroblast/osteoblast function, polymorphonucleocyte function
DHX considerations
- Patient attendance
- Motivation
- Self-performed plaque control
- What treatment has the patient accepted in the past?
- Suitable for a surgical procedure
- Presence of bruxism?
risks of placements of implants prior to growth stopped
Relative infra-occlusion
Suboptimal aesthetics
Occlusal disharmony
Implant fenestration
due to continued downward and forward growth of jaw but implants fixed
smile line considerations
Defined as
High- >2mm ST show
Medium- <2mm ST show
Low- lip covers >25% of teeth
Will impact on visibility of implant and prosthesis
Peri-implant ST often most difficult to mask
Key to establish if VME present
gingival biotype considerations
Described as
- Thick flat
- Thick scalloped
- Thin scalloped
Most commonly differentiated through probe visibility (De Rouck 2009)
Will impact on risk of recession, risk of implant visibility through tissues
- Thin (recession and unpredictable healing)
- Thick tissue more likely to scar and less likely to develop papilla – e.g. flat
Associated with underlying bony morphology
what determines the presence of papilla
In a single tooth site the distance from the bone crest/alveolar bone to the adjacent contact point will determine the presence of the adjacent papilla
infection effect on implant
Infection at the proposed implant site will affect the survival and success of dental implants
Categorised as
- Acute
- Chronic
Little evidence that chronic infection at local site will impact on success or survival of dental implants (Waasdorp 2010)
How long will infection take to resolve prior to implant placement?
- Infection usually resolved 2 weeks
- If not placing immediately, early placement protocol usually protocol of choice- Leave 4-8 weeks
surrounding dental implant site factors
restorative status adj teeth
suboptimal aesthetics if there is recession due to subgingival restoration margins (encroach on biologic width)
consider replacing them?
width of edentulous span
assess bone for implant placement in
3 dimensions
volume
orientation
any relevant local anatomy
maxillary anatomy to be aware of
maxillary sinus
nasal floor
naso palatine canal
Infra orbital nerve
how to determine risk of implant placement
ITI’s classification system SAC: Straightforward, Advanced, Complex.(international team for implantology)
soft tissue stability post implant
consideration for recession
Gap of <5mm interproximally will be entirely filled by soft tissue (to alveolar crest)
Gap of >5mm = black triangles and recession likely
