Dental implants are commonly used to replace single or multiple missing or damaged teeth. Once natural teeth are removed the jaw bone will shrink where the tooth or teeth have been removed. Over time the jaw bone will continue to decreasing in volume and the density can also become softer. Removable dentures do not provide any stimulus to the jaw bone to maintain the normal shape and form of bone. Healthy natural teeth transfer pressure and stresses and this in turn maintains the jaw bone due to bone being a dynamic tissue which responds to this stimulus.
We see many cases in our clinic where patients have lost teeth and have used a removable denture for a prolonged period of time. In many cases the amount of bone that is available for dental implant treatment is reduced but still sufficient for dental implant treatment. In some cases the volume of bone can be so limited that dental implant treatment can be complex. Dental implants need good amounts of bone tissue in order to provide a secure and stable foundation for the implants.
The upper jaw is usually softer and has less volume of bone for dental implant treatment. We also see that the upper jaw tends to resorb or shrink more after tooth loss. Zygomatic implants are longer dental implants that are inserted into the zygomatic bone ( cheek bones ). They are not used in the majority of cases for upper dental implant treatment but in cases where there is extreme atrophy of the upper jaw bone. The implants are longer and used only in the upper jaw.
A 53 year old female patient presented to our clinic with a main complaint of multiple missing teeth and an inability to cope with a removable denture. There were a number of existing natural teeth still present however these were mobile, infected and causing some discomfort during function. The patient wanted to replace her dentures and problem teeth with dental implants. After a thorough implant consultation it was decided that the mobile teeth needed to be removed and all infections cleaned. A removable denture was made and the bone allowed to heal. Following a 4 month healing period 3 dimensional ct scans were taken to ascertain the volume of bone that was available for implant treatment. Whilst there was sufficient bone in the anterior aspects of the upper jaw, we found limited height and width of bone in the posterior regions.
The patient was given the option of grafting bone in the posterior regions or zygomatic implants. In an attempt to avoid bone grafting ( sinus lift surgery ) the patient opted for zygomatic implants which do not require bone grafting. There are advantages and disadvantages of each approach. Whilst bone grafting is considered to be less invasive when compared to zygomatic implants the results can be unpredictable and generally take longer to heal. Zygomatic implants avoid the need for bone grafting but do involve a more invasive surgery which could also involve greater risks and potential complications.
The surgery was carried out under conscious sedation. Four conventional root form implants were placed in the upper anterior region and two zygomatic implants were placed in the posterior regions. All of the implants were embedded securely into healthy bone. A stability test was carried out following the implant placement and the implants were adequately secure to support a provisional fixed bridge on the same day of the surgery. After 4 months of healing the implants, gum tissues and bone were checked and confirmed to be healing well. New impressions were taken to complete a definitive implant supported bridge.
The patient also completed implant treatment on the lower arch. The mandible had a greater volume of bone of very good quality. A standard protocol of teeth on 4 implants was used. The patient will be reviewed every 6 months for the first year and then yearly to ensure that the implants and bridges are functioning well. The bridges are removed yearly to ensure that they are being correctly maintained and cleaned. The bridges are made with a passive seating technique using an acrylic, composite resin and metal alloy.
For more information about dental implants please visit our website www.brightonimplantclinic.co.uk