non biological allografts (e.g. bioactive glass) sterilised bone grafts (e.g. bovine bone xenografts) bone bank allografts (e.g. human demineralised bone matrix) autologous bone grafts (e.g. same patient donor hip / skull / rib)

Collagen Membrane

Tissue Engineering - Maxillary Atrophy

We have been able to demonstrate successful regeneration of the upper jaw using Engineering Assisted Surgery™ techniques.

The wasted upper jaw (Maxillary Atrophy) occurs in patients following an upper dental clearance, and historically has been an extremely difficult problem to solve, often involving major surgery, not without risk for many patients.

Patients with Maxillary Atrophy have a significant disability which significantly impares the quality of life. Upper dentures become extremely loose to the extent that they cannot be worn - not even with the use of denture fixative. The condition may be initiated by the rocking motion of an upper denture in a patient with missing lower posterior teeth, and who does not wear a occlusion balancing lower denture. This rocking motion is produced by the lower anterior incisor teeth, which bite only into the front upper denture. The underlying bone cannot withstand this trauma - and disappears.

The management of this condition has been revolutionised by Engineering Assisted Surgery™ techniques and by Tissue Engineering in particular. Safer treatment options are now possible without recourse to major surgery - or even hospitalisation - as an outpatient procedure in the dental surgery, under local anaesthesia.

Following upper jaw regeneration, upper dentures can be made and stabilised with dental implants, without palatal cover, greatly enhancing the quality of life for patients. A stabilised denture is known as an Overdenture.

Lower overdentures can be very comfortable and effectively stabilised using an inexpensive Mini Dental Implant System. Many patients state that these overdenture solutions produce result which feel as is they have been given back their own teeth.

The cost of this treatment modality is very much reduced, making these treatment options more accessable for patients.

Case 1

Computer Planning

Platelet Rich Plasma - Blood Clot and Growth Factors

Platelets are rich in:

• chemical messengers

• growth factors
  
  

• Promotes enhanced healing and regeneration of bone and soft tissue

• Guides the growth of soft tissue in the reconstruction of  defects

• Guides the growth of bone in the reconstruction of defect
  
• 15-30% increase in bone trabecular density

• acceleration of bone maturation by 2 months

• earlier placement of implants possible
  
  
  
  Surgery
  
       
  
       
  
  

     

Transitional Stabilisation (6months)

OPT Radiograph 6 months

Radiographs show that the implant has lost its attachment to bone, but the clinical image shows that the implant although submerged is still functioning without any evidence of peri-implantitis.

Transitional Stabilisation at 6 months

Denture Conversion and Stabilisation @ 6 months

Long 18 mm inexpensive Mini Dental Implants were placed in the grafted area and denture stabilisation was achieved without recourse to major surgery, with excellent retention of an upper denture.

Over a 6 month period several Mini Dental Implants were lost and were simply replaced without significant increase in cost.

Outcome - 6 months

Lower Dental Clearance and Provision of New Dentures

A lower clearance was carried out at 6 months with stabilisation of an immediate lower denture.

The upper denture was made without palatal cover.

Note the facial rejuvenation achieved with the overdenture technique.

This has been achieved without recourse to soft tissue enhancement of any kind, and illustrates the importance of the teeth and jaws and lip support achieved by the overdenture in the generation of facial harmony.

There is....

• improvement in muscle tone
• better exposure of the upper incisor teeth
• filling out of the nasolabial folds.

This outcome would not have been possible with single tooth implant treatment plan unless combined with major jaw advancement osteotomy surgery, which still would have provided an inferior rejuvenation effect.

Outcome - 5 months post clearance

Outcome @ 2 years

Outcome @ 2 years confirms osseointegration of 4/7 MDI implants in the maxilla. Two implants in the anterior maxilla and one implant in the region of the right premolar (bicuspid) are mobile. Two of the loose implants appear to be tissue integrated - i.e. adherant to soft tissue to the effect that the implants are functioning, and are assisting in a superb retention of the upper palateless denture.

This is an important observation and may have importance in the creation of a tissue integrated system which may function in the absence of bone. Loose implants remain under close review and may be augmented with bicon implants as a two staged technique.

2 year Outcome - Palateless Upper Denture

Mandibular Implants

(despite gingival recession all implants are osseointegrated and functioning)

Outcome: Excellent Retention @ 2 years

Click Image for Patient Comment

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Overdenture Retention

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Case 2

Computer Planning

A case of severe maxillary atrophy treated with the same method of grafting as Case 1.

The patient decided to undergo treatment of the maxilla only.

No hospitalisation was required.

An initial plan using Mini Dental Implants was converted to bicon implants http://www.bicon.com following loss of implants (see below).

Bone density was assessed and bicon Implant placement was planned using Simplant 9 software.

Grafted Maxilla

Computer Planning - Simplant 9

http://www.materialise.com/simplant/main1_ENG.htm

Bicon Implants

Bicon Implant Placement - Virtual Reality

Simplant 9 Computer Planning

Bone Density in Grafted Maxilla

Grafted Bone and Misch Grading of Bone Denisty

• D1 (dark grey) at the apex of the implant (very dense bone)

• D2 (blue) in the apical third of the implant (dense bone)

• D3 (green) in the mid third of the implant (almost extending into D2)

• Platelet rich plasma moves bone denisty up by one Misch Grading e.g. from D3 - D2

Outcome

Click Image for Patient Comment

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Overdenture Retention

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Discussion

The use of Engineering Assisted Surgery™ techniques in association with Tissue Engineering and the use of Mini Dental Implants secured a successful outcome possible in Case 1, without the need for major surgery, general anaesthesia nor hospitalisation.

In Case 2 initial placement of Mini Dental Implants initially provided excellent retention and were replaced with bicon implants as a two-staged procedure. This resulted in a successful outcome.

It is interesting to note in Case 2 that one of the Mini Dental Implants fractured in dense bone. This implies that osseointegration occurred and that the fracture was related to loading of the implant in dense bone graft with possible compromised elasticity.

Key Points:

• EAS Technology has converted two very difficult case into comparatively easy cases
  
• Minimal Surgery under local anaesthesia
  
• Single Site Surgery (no second surgery site for donor bone graft)
  
• No Hospitalisation
  
• Early rehabilitation
  
• Low Risk - Overdenture option easier to salvage than individual tooth replacement

• Low Cost
  
• Excellent Outcome - Superior Dental Aesthetics (Gum line) with denture flange

• Excellent Outcome - Superior Facial Rejuvenation with Overdenture option

• Individual tooth replacement with dental implants - poor gum aesthetics and little rejuveneation without major jaw advancement surgery