Teeth on Dental Implants

There are various materials and techniques used for replacing teeth on dental implants.

The choice of materials will be advised based on each patient’s individual requirements and must be decided at the start, as the choice has an influence on the numbers and positions of actual dental implants required.   

Fixed Teeth on Implants

Zirconia or titanium based zirconia abutment and zirconia or all ceramic crown

A customised implant company-manufactured or CAD CAM solid high-strength zirconia abutment is screwed into the implant. This supports a CAD-CAM milled zirconia crown core layered with customised porcelain to match the patient's natural teeth

Indications: Single teeth at front of mouth where best aesthetics are required. Crown is cemented or bonded

Advantages: Best aesthetics, light transmission and tissue response to zirconia

Disadvantages: Less tough than titanium abutments and more costly. Unsuitable for larger reconstructions where multiple teeth are missing or at the back of the mouth.

Titanium abutment and ceramometal* crown or bridge
(*ceramometal = precious metal porcelain = porcelain fused to precious metal)

A customised implant company-manufactured solid high-strength titanium alloy abutment is screwed into the implant and used to support a custom-shaped and cast precious gold alloy core layered with high-strength customised porcelain to match the patient's natural teeth or create a uniform customised shade for multiple teeth.

Indications: All teeth from single tooth to full mouth of single teeth to large full arch bridges. Crowns or bridges are cemented or screwed into position.

Advantages: Best combination of maximum strength and good aesthetics for back teeth or multiple teeth where matching shade nuances to natural teeth is not critical. Best durability.

Disadvantages: Can be costly for multiple units due to gold alloy content. Where full arches need to be replaced, 3 to 4 segments may be required for technical reasons requiring more implants to be placed at the start of treatment. Breakage is infrequent but can be laborious and costly to dismantle and replace. 

Titanium abutments with titanium or cobalt chromium framework and acrylic teeth

Customised implant company-manufactured solid high-strength titanium alloy abutments are screwed into the implants and used to support premium high-density factory-manufactured acrylic denture teeth and pink veined acrylic gum bonded to a supporting precision cast gold alloy or CAD CAM milled titanium or cobalt chrome framework bridge.

Indications: Full arch screw-retained bridgework only, especially in cases where there has been irregular tissue loss and only a limited number of implants can be placed.

Advantages: Very good tooth and gum combination aesthetics can be achieved. Considerably less costly than full arch ceramometal bridgework and can be used on fewer implants. Technically easier construction for laboratory. Shock absorbing function when biting especially when both arches are implant supported when there is no “give” as exists with natural teeth. Screw retention makes removal straightforward for cleaning and servicing.

Disadvantages: Mainly suitable for full arch bridges or large sections. Screw holes apparent, though my preference is to design these bridges so that the screw holes are on the inside surface. Lack of cement inside bridge leads to percolation of bacteria under the structure that can cause odour.

Caution

The acrylic teeth on this kind of restoration tend to deteriorate quite rapidly in the mouth. Relatively frequent servicing can be required every 1- 2 years as acrylic wears, chips, stains and scratches. Acrylic tooth chipping is relatively common and can be troublesome, especially when opposing natural teeth. For this reason, the acrylic veneering on these cases is not guaranteed. Approximately £1,500 - £1,800 an arch may be required for a full-service, consisting of removing the bridge, replacing the teeth and gum on the metal  framework and refitting with new prosthetic screws as required. This can normally be done in one day or overnight during which time you may need to be without teeth. Composite resin is more durable than acrylic though initially more costly to manufacture. However, repair of composite resin in the mouth is much easier than repair or replacement of acrylic teeth and it is less likely that the bridge would need to be removed for repair..

Titanium abutment and gold, titanium or cobalt chrome framework and composite resin teeth

As above but where where composite resin (the material used in tooth coloured fillings) is used to sculpt tooth and gum onto the framework instead of use of acrylic.

Indications: Full arch or sectional, usually screw retained (but occasionally cemented), bridgework or long-term provisional bridges especially in cases where there has been irregular tissue loss and only a limited number of implants can be placed. Metal composite crowns and bridges are often used as provisional crowns when strength and durability are required for between three months to 2 years prior to final metal ceramic restorations.

Advantages: More durable than gold / acrylic and minor chips and breakages easy to repair in the mouth. Very good tooth aesthetics can be achieved. Less costly than full arch ceramometal bridgework but more costly than gold acrylic as very time-consuming and requires great skill to build individual teeth in composite resin layers. Shock absorbing function when biting especially when both arches are implant supported and there is no “give” as exists with natural teeth. Screw retention makes removal straightforward for cleaning and servicing but can also be cemented to eliminate screw holes as the material used can be repaired in the mouth unlike acrylic.

Disadvantages: Long-term staining and chipping still possible though less than acrylic. Composite resin gum work can appear more opaque and artificial compared to acrylic but still very natural.

Removable teeth on implants

I would normally prefer to provide a patient with fixed teeth when providing them with dental implants. However occasionally, it is necessary to have a removable denture that is supported by or retained by dental implants.

Implant-retained dentures may be recommended when :

  • Insufficient bone is available to place multiple implants and the scope of bone augmentation required is beyond what a patient is comfortable with, perhaps due to advanced age or complicated medical history.
  • A large amount of jawbone structure bone has been lost so that the denture is required to fill out the soft tissues of the face. This cannot easily be achieved with fixed bridgework.
  • When a patient has a clenching or grinding habit and a history of breaking fixed teeth. A  denture designed to unclip when extreme force is applied can be used to dissipate destructive forces. It is also cheaper to replace in the event of breakage or wear.
  • A spare can be easily provided for reasonable cost.
  • The patient is used to having dentures or prefers removable teeth as they may not have the manual dexterity to cope with cleaning around fixed bridgework
Various modern CAD CAM or low profile attachment mechanisms are available to give excellent retention to dentures, immobilising them during eating but allowing removal for cleaning:

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