Orthodontic Bone Anchorage Devices
Also known as Temporary anchorage devices
What are bollard skeletal anchorage devices
Bollard skeletal (bone) anchors are a fundamental part of orthodontic treatment, planning and subsequent treatment delivery. These anchorage devices are commonly used to facilitate movement of teeth within the upper and/or lower jaws - when a large amount of tooth movement is required, or dental anchorage is insufficient because of absent teeth or periodontal loss (loss of bone around the teeth).
These devices are referred to by an array of names including: mini-plates, micro-implants, micro-screw implants, mini-screws or temporary anchorage devices (TADs).
A description of the bollard miniplate:
The bollard mini-plate device consists of 3 parts:
- A 2 or 3 hole titanium mini-plate
- A neck (round connecting bar), and
- A cylinder-shaped fixation unit with a blocking screw.
Through the holes in the mini-plate the bone anchorage device is then fixed by titanium screws.
Where are the devices placed
- In the cheekbone.
- In the nasal bones of the upper jaw.
- In the canine (teeth next to your four front teeth) region of the lower jaw.
- In the molar (wisdom teeth) region of the lower jaw.
What does the surgery involve
Your orthodontist has referred you to a specialist oral and maxillofacial surgeon to perform this procedure.
The anchorage devices are generally placed under local anaesthetic. In some difficult cases however, the devices are placed under intravenous sedation or general anaesthetic.
Maxillary or infrazygomatic placement of the bollard mini-plate
The specialist surgeon will make an L-shaped incision to expose the required bone which will allow placement of the bollard mini-plate. The incision is strategically made to enable secure contact to the exposed bone using 2.3mm x 5mm titanium screws and bollard plates. The first screw is not completely fixed in order to allow some rotation of the mini-plate. The lower hole is drilled and the screw is then inserted, followed by the upper one and all are fixed for a strong and stable placement. Resorbable stitches are then placed to close the incisions.
What to expect following surgery
Following surgery, you will need to gently rinse your mouth with an antiseptic mouth wash for 3-4 days and clean around the bone plates with a cotton swab. It is important that you do not irritate the bone anchors with your tongue or fingers.
Your surgeon will allow a 3-4 week healing period following surgery before undertaking any further treatment.
Mandibular (lower jaw) placement of the bollard mini-plate
Your specialist surgeon will make an L-shaped incision to the lower jaw in the lower canine region to expose the bone to enable placement of 2.3mm x 5mm titanium screws and bollard plates. The first screw is inserted but not completely fixed in order to allow some rotation of the mini-plate. The second hole is drilled and the screw is inserted in the mandibular (lower jaw) region and both are fixed for a strong and stable placement. Resorbable stitches are then placed to close the incision sites.
What is a Bollard Mini-Plate with Hook
Description of the bollard mini-plate with hook
The general design of the bollard mini-plate (with hook) is completely similar to the design of the standard bollard, except for a part in the mouth which consists of a small tube with an elastic hook. The purpose of this hook is to facilitate attachment of elastics or spring coils by your orthodontist, if required.
(SEE BOLLARD MINI-PLATE ABOVE)