What are healing abutments (gingiva formers) and cover screws in implants?
- a cover screw or
- a healing abutment (gingiva former)
In both cases certain professional criteria have to be met, which need to be taken into account by the implanting dental specialist.
1. When sealing with a cover screw a flat-head screw is placed inside, so the gum above it can be completely sealed. The benefit of this method is that the cover screw is deep underneath, and completely sealed by, the gums allowing the wound to heal without complications and minimising the risk of infections. The downside of this solution is that another surgical intervention (viz. the exposure of implants) will be necessary one month before the fabrication of the permanent tooth replacement, during which the gums are exposed and the implants are identified individually, and the cover screws are unscrewed and gingiva formers (healing abutments) are screwed into their place. Now the gums require another healing period so that the precision impressions can be taken from a fully healed gum level.
Cover screw in the implant (source: internet)
Cover screws are indicated in the following instances:
- Bone graft surgery, sinus lift, vertical and horizontal bone graft, in other words, where membrane, i. e. bone graft material is used and complication-free healing is all-important.
- The primary stability of the implant is inadequate with torque values less than 30 Ncm on installation.
- Smoking patients.
Follow-up panoramic radiograph following installation of the implants. As the radiograph clearly shows, the stability of the lower implants allowed for the placement of healing abutments, while in the upper arch cover screws were screwed into the implants due to lesser stability and a contour augmentation bone graft. Taller screws (gingiva formers) were used below, whereas flathead screws (cover screws) were inserted above.
The maxilla following implant surgery and healing. The implant is fitted with a cover screw which seals at bone-level deep underneath, and does not show through or protrude over the gum line
2. When sealing with a gingiva former (healing abutment) a taller screw sticking through the gum is inserted into the implant. The healing abutments mould the gum into the desired shape for the permanent abutment and tooth replacement to have a perfect gum contour. If the gums are sutured with a gingiva former following implant surgery, 3 months later the dentist will take precision impressions of a fully healed gum surface that no longer bleeds. The thorough cleaning of the healing abutments with a soft bristle brush is crucial in preventing the build-up of tartar and bacteria, the presence of which may give rise to inflammations which may even entail the rejection of the implant.
Healing abutment in the implant (source: internet)
Healing abutments are indicated in the following instances:
- The primary stability of the implant is adequate with torque values exceeding 30 Ncm on installation
- The patient does not smoke.
- No bone graft was performed on the installation of the implant.
- No provisional denture is worn at the site of the surgery.
Panoramic radiograph of implants sealed with healing abutments following implant surgery:
Healing abutments in the implants of the mandible
Gums moulded to shape by gingiva formers around the implants of the mandible
Whatever screw is installed following implant surgery, the instructions of the treating specialist must be observed at all times. In order for the replacement teeth to be aesthetic and successful in the long-run, cooperation is required between the dental staff and the patient.