Wound Healing and Anatomical Considerations Flashcards
What are the 2 types of implant healing
Fibro osseous integration
Osseointegration
What is fibro osseous integration
Layer of fibrous connective tissue formed between a dental implant and surrounding bone
Fibro osseous integration is __ contact
tissue to implant
How is the short and long term success of Fibro osseous integration
Initially good success rates but extremely poor long term success
this type of implant healing is considered a failure by todays standards
Fibro osseous integration
Seen in earlier implant systems
Fibro osseous integration
T/F: Fibro osseous integration has bone direct contact with the implant
FALSE
No bone direct contact with the implant
What is osseointegration
The direct contact between living bone and a functionally loaded dental implant surface without interposed soft tissue at the light microscope level
Osseointegration is __ contact
Bone to implant
Osseointegration:
A __ healing process whereby clinically asymptomatic rigid fixation of implant is achieved and maintained in bone during __
time-dependent
functional loading
What are the 4 phases of healing
Hemostasis
Inflammation
Proliferation
Remodeling
Explain the 4 phases of healing
Hemostasis - clot formation within minutes
Inflammation - recruitment of immune cells
Proliferation - angiogenesis and fibroblast activity
Remodeling - maturation of bone (osseointegration)
What happens in the first few hours of healing
Blood clot is in contact with the implant surface
- erythrocytes, neutrophils, and macrophages are trapped in a network of fibrin
What happens in days 3-4 during healing
The clot is replaced by granulation tissue composed by mesenchymal cells, disorganized connective tissue matrix and the first vessel sprouts are evident
What happens 1 week after healing
Most of the inflammatory cells are resorbed and immature woven bone can be evidenced together with newly formed vessels
What happens 2 weeks after healing
Woven bone formation is more pronounced and surrounds the whole implant mixed with old bone which is a clear sign of osteogenesis. Osteoclast formation is evidenced and contributes to bone remodeling
What happens 4 weeks after healing
Newly formed mineralized bone extends from the prepared bone surface to the implant coating
What happens 6-12 weeks after healing
Bone enters the remodeling phase, more mature bone with the presence of primary and secondary osteons is evident
Osseointegration: Initial stability
The degree of tightness of a dental implant immediately after placement in its prepared osteotomy.
An implant is considered to have initial stability if it is clinically
immobile at the time of placement
Osseointegration: Secondary Stability
The fixation of a dental implant to the bone over time and after osseointegration has occurred
Bone interface is stronger __ compared with __
On the day of implant placement compared with 3 months later
(Look at graph)
What 4 things are needed for osseointegration
- A biocompatible material (the implant)
- Atraumatic surgery to minimize tissue damage
- Implant placement in intimate contact with bone
- Immobility of the implant, relative to bone, during the healing phase
Osseointegration:
Supporting bone is in __ with the implant surface
direct contact (no periodontal ligament)
Connective tissue zone
fibers running parallel to the implant surface and no inserting fibers
What are some systemic, local and technique factors influencing healing
Systemic = smoking, diabetes, medications (bisphosphonates)
Local = surgical trauma, implant surface, infection
Technique = flapless, open surgery
Smokers experienced almost twice as many
implant failures compared with nonsmokers
Smokers have a decreased resistance to __
inflammation and infection
With smoking there is a high failure rate of
implants and bone grafts
What is the relative contraindication and absolute contraindication with smoking
Any amount of smoking = relative contraindication
Excessive smoking (>1.5 packs/day) = absolute contraindication until smoking cessation
Direct correlation between implant osseointegration and __ with diabetes
glycemic control
Diabetic patients are prone to developing __
infections and vascular complications
What is the contraindication for diabetes with implants
Well-controlled diabetes: NO contraindication
Insulin-controlled: Contraindication depending on the state of control
When might a patient be taking bisphosphonates
Treatment of osteoporosis, metastatic cone cancer, and paget disease
With bisphonsphonates there is reduced __ via a direct effect on the osteoclast
bone resorption
Bisphosphonates can cause drug-induced __
osteonecrosis of the jaw
Contraindications for bisphosphonates with implants
Oral bisphosphonates: relative contraindication
IV bisphosphonates: absolute contraindication
What is surgical trauma
The surgical process of the implant osteotomy preparation and implant insertion results in a regional acceleratory phenomenon of bone repair around the implant interface
The implant-bone interface is weakest and most at risk for overload at __ because the surgical trauma causes __
3 to 6 weeks
bone remodeling at the interface
Proven to be critical for adhesion and differentiation of cells during the bone remodeling process essential to osseointegration
Implant surface
What implant surface gives weaker bone integration and which gives stronger bone responses
Smooth (0-0.4) and minimally rough (0.5-1) = weaker bone integration
Moderately rough (1-2) = stronger bone responses than rough (>2)
Implant surface increases what 5 things
increased surface area
increased cellular attachment
increased primary stability
increased bone implant contact
increased success rate
Implant surface features can be subtractive and additive. What s subtractive and whats additive
Subtractive = Etching with acid, blasting with an abrasive material, treatment with lasers
Additive = hydroxyapatite coating and titanium plasma spraying, oxidation or anodization
Open surgery X flapless
Good: Less invasive, maintains tissue vasculature, no vertical incisions, less discomfort
Bad: Malpositioning (unless guided)
Anatomical considerations:
Maxillary sinus
Bone quality in the posterior maxilla is typically poorest of any area
Bone resorption and increased pneumatization of the sinus
Anatomical considerations:
Nasal cavity and incisive canal
Vital structures that define anatomic limitation of implant placement
Implants should be placed 1 mm short of the nasal floor and should not be placed in the maxillary midline
What are the 4 maxillary Anatomical considerations:
Maxillary sinus
nasal cavity/floor
incisive canal
Bone density
What are the 4 mandibular Anatomical considerations:
inferior alveolar nerve
anterior loop
mental foramen
Anatomical considerations:
Anterior loop of IAN
The anterior loop measurement should be added to the 2-mm safety zone to ensure adequate space between the implant and foramen
Anatomical considerations:
Inferior alveolar nerve
Minimum 2 mm safe distance between the implant and nerve
Pre, intra, post operative PA’s super important
CBCT when not sure
What 2D images for general assessment
Panoramic
What 3D images for precise anatomical mapping
CBCT
