Implant Intro Flashcards
What are questions to ask when evaluating for implant placement
Bone Quantity good? Bone Qualit good? Soft tissue Quantity Soft tissue Quality Can it be placed now? Is prep work needed
Albrektsson Criteria for sucess
- No mobility
- No peri implant radiolucency
- vertical bone loss less than .2mm after first year
- absence of signs/symptoms of pain, paresthesia, infection, etc
Other criteria for implant sucess
- Oseointegration
- functional restoration
- acceptable esthetics
- long term tissue health
Prereqs to implant therapy
Med hx
Dent Hx
Oral health status
adequate soft tissues and bone
Diabetes and Implant success
-mixed results but most studies don’t look at control of diabetes
Oates 2014
No evidence of altered implant survival with elevated HbA1c, BUT looked only at edentulous patients
Osteoporosis and Implants
No difference between studied groups
-unless smoking involved then 2.6% increase in failure rate
2 types of drugs for osteoporosis
- Antiresorptive drugs
- Antiangiogenisis agents
Antiresorptive drugs
alter bone metabolism mainly by inhibiting osteoclast function; altered bone metabolism in patients with bone cancers
– Bisphosphonates
– RANK ligand inhibitor (denosumab) – (monoclonal antibody
to RANK ligand (RANK‐L)
Antiangiogenisis agents
Antiangiogenesis agents – interfere with new blood
vessel formation; used in patients with certain types of
tumors/cancers (sunitinib, sorafenib, bevacizumab,
sirolimus)
Bisphosphonates
– decrease osteoclastic activity
– Oral agents:
•Alendronate (Fosamax), Risedronate (Actonel), Ibandronate
(Boniva)
–IV agents:
•Pamidronate (Aredia); Zolendronate (Zometa)
– given IV once every few weeks or months (mainly for bone
malignancy or Paget’s disease; used in some severe osteoporosis
cases)
• Reclast
– Yearly IV infusion of zolendronate for osteoporosis
“Osteonecrosis of the jaw”
originally
identified in patients taking bisphosphonates
– seen after invasive procedure like flap surgery,
implant placement or tooth extraction; spontaneous
cases have frequently been reported (make up large
percentage of cases)
– signs of ONJ: jaw pain, exposed bone, tooth mobility,
numbness, bone sequestration (similar to
osteoradionecrosis)
Bisphosphonate mechanism
• Bisphosphonates bind to bone mineral with minimal
metabolism of the drug
• Drugs are internalized by osteoclasts, resulting in:
– inhibition of osteoclast recruitment
– inhibition of osteoclastic activity
– decreased osteoclast life span
• Drugs also inhibit endothelial cell function in bone:
– may impair blood supply to bone
Which has greater risk for causing MRONJ, oral or IV infusible
Infusible
Does risk of MRONJ decrease after discontinuation of drug
No
Stats for MRONJ risk of different drugs in cancer patients
•Risk of ONJ in cancer patients taking placebo in clinical
trials = 0 ‐ 0.019% (0‐1.9 cases per 10,000 patients)
•Risk of ONJ in cancer patients taking zolendronate =
0.7‐ 6.7% (70‐670 cases per 10,000 patients)
– 50‐350 times higher risk for IV zolendronate than placebo
•Risk of ONJ in cancer patients taking denosumab = 0.7‐
1.9% (70‐190 cases per 10,000 patients)
– risk close to zolendronate
•Risk of ONJ in cancer patients taking bevacizumab
(antiangiogenic agent) = 0.2% (20 cases per 10,000)
MRONJ stats of different drugs in patients with osteoporosis
•Risk of ONJ in large, long‐term studies of oral
bisphosphonates for osteoporosis was 0.1% (10 cases
per 10,000), which increased to 0.21 (21 cases per
10,000) among patients with greater than 4 years of
oral BP exposure
•Risk for ONJ among patients treated for osteoporosis
with either zolendronate annually (Reclast) or
denosumab semi‐annually (Prolia) (0.017 – 0.04%)
approximates the risk for ONJ of patients enrolled in
placebo groups (0%‐0.02%)
Take homes of MRONJ
•Risk of ONJ for drug regimens used to treat
osteoporosis is more than 100 times lower than risk
for drug regimens used to treat cancer
•Risk for ONJ does increase with time of use (for both
cancer regimens and osteoporosis regimens)
Dental guidelines for MRONJ at risk pos (IV)
IV agents: Procedures that involve direct osseous injury
should be avoided. Recommend no surgery (including ext)
in patients taking IV agents (do endo, coronectomy, etc,
rather than ext tooth); recommend no dental implants in
these patients.
• If patient is about to start IV agents, try to remove teeth with
poor prognosis ahead of time and make sure patient’s oral health
is good before drug initiation
2014
INFORMED CONSENT
MRONJ risk pt oral med Dental guidelines
-patients taking oral agents < 4 years and have no other”
“clinical risk factors (e.g., diabetes, corticosteroids, smoking, alcohol, poor OH, chemotherapy, etc.): no alteration in planned surgery. If implants are placed,”
“nformed consent concerning possible future implant failure.”
• Patients taking oral agents > 4 years with or without any
concomitant medical therapy (steroids/antiangiogenic
agents): contact prescribing physician to discuss
discontinuation of drug for 2 months prior to oral surgical
therapy and until after bony healing is complete (which
could be several months after tx)
MRONJ drug holiday
dictated by physician not dentist
What are some medications types that might alter surgical plan
– anticoagulants (Coumadin/warfarin)
–diabetes medications (e.g., insulin)
–CNS depressants, especially if conscious sedation is
to be used (antidepressants, antianxiety agents,
some antihistamines, others)
Radiation therapy impact on Implants
– Increases risk of implant failure (and complications such as
osteoradionecrosis)
– Failure rate dependent on total radiation dose
• 2.6% failure rate with <55Gy total radiation
• 10.1% failure rate with >55Gy total radiation
– Hyperbaric oxygen may decrease failure rate, but little direct
evidence
Smoking and Implant SURVIVAL
• Systematic review analyzed 14 articles with
implant survival data for smokers (12 to 144
months)
• Overall survival rate:
SMOKERS 89.7%
NONSMOKERS 93.3%
Pooled estimate of difference in overall survival rate was 2.7%
better for nonsmokers (p=0.0009). Statistically significant, but not
clinically impressive.
Smoking and Implant SUCCESS
• Analyzed 7 articles with implant success data for
smokers (12 to 48 months)
– Varying success criteria in articles
• Overall success rate:
SMOKERS 77.0%
NONSMOKERS 91.0%
Pooled estimate of difference in overall success rate was 11.3%
better for nonsmokers (p=0.005). Statistically significant, and
impressive clinical difference.
Smoking and Implant big pictures
– Smoking decreases implant survival, but mainly at
maxillary sites
– Smoking decreases implant success in both
maxillary and mandibular sites
– Impact of smoking is lower with use of microroughened
surfaces than for machined surfaces
Does oral health need to be controlled before implants
Yes
Periodontitis and survival
– Implant survival lower when subjects had more than
30% of teeth with bone loss >4mm (i.e., history of
periodontitis)
even if disease was currently under control!
Periodontitis and Perioimplantits
O.R. for peri‐implantitis was 4.7 in subjects with
>4mm bone loss at >30% of teeth compared to <30%
of teeth at time of implant placement
• % of subjects who developed peri‐implantitis requiring
surgery, and/or systemic or local antibiotics:
– Periodontally healthy = 10.7%
– Hx of treated moderate periodontitis = 27.0%
– Hx of treated severe periodontitis = 47.2%
Periodontits and roughened implants
Implant survival rates are slightly lower in patients with
past hx of periodontitis, but survival rates are generally
>90% with microroughened surfaces
Implant PD and periodontitis
– Periodontally healthy = 4.2mm
– Hx of treated moderate periodontitis = 5.1mm
– Hx of treated severe periodontitis = 5.5mm
• % of implants having 6mm PD at 1+ sites during maint:
– Periodontally healthy = 6.6%
– Hx of treated moderate periodontitis = 29.5%
– Hx of treated severe periodontitis = 45.6%
Why do you want adequate soft tissue
– to cover implant site – to ensure esthetic result – to allow long‐term maintenance of health
When is it best to treat soft/hard tissue defects
Prior or at implant placement
Why do you want adequate hard tissues
– to allow for implant placement – to ensure implant stability – to allow long‐term maintenance of health
What drives implant placement location
Where it needs to be restoratively not where tissues are adequate. If tissues can’t be augmented then implant shouldn’t be used
How is bone located
– palpation – bone sounding – radiographs • Incisions should always be placed over bone • Implant must be placed in bone or bone must be augmented Anatomical Considerations • Where is the bone?? – palpation •Least accurate technique •Can determine gross bony contours •Often overestimates/underestimates amount of bone truly present
Palpating Bone
•Least accurate technique •Can determine gross bony contours •Often overestimates/underestimates amount of bone truly present The time to find out how much bone you have is not the day of surgery
Bone sounding
• patient is anesthetized and probe is placed through soft tissue to bone • bone can be “mapped” and transferred to cast • Better to use template that covers entire F&L
Radiographic imaging of bone
•Very useful
•Can still under/overestimate actual bone
•Can choose between many types of
radiographs (2‐D and 3‐D)
– variations in magnification and image distortion
can be critical
•3‐D imaging is a huge plus for many patients; not as
important for others
