Since 2007, I have been giving the lecture on complications of dental implant surgery to the Graduate Diploma in Dental Implantology course in the National University of Singapore. It is important for dentists embarking on providing dental implants in their practice to understand what the potential complications are and how to manage them. But what ARE complications?
A complication is an unwanted outcome that usually does not happen but can happen. However, we need to differentiate it from a sequelae of surgery, which is something which will naturally happen after a surgical procedure. When you undergo surgery, there will be some pain, some swelling and maybe some bleeding and bruises. This is a natural response of the body to surgery. These occurences will happen. It's only a matter of degree. Some people swell a lot, some hardly, while others bruise more extensively than most people. These are normal and natural and they are self limiting ie they go away on their own.
A complication, on the other hand, usually does not happen. If it happens, it does not necessarily mean that the dentist has messed up. Surgery is not an exact science and variations in anatomy and physiology do exist that can complicate the procedure even with the best planning. There are many potential complications that can happen with dental implant surgery. I won't go into the details here but the most important are the following:
1. Nerve injury:
this is probably the most important complication to note before any implant surgery in the lower jaw. There is a nerve in the lower jaw that provide sensation to the lip. Inserting dental implants into the bone may injure the nerve leading to numbness of the lip. Depending on the degree of injury, the intensity and extent of numbness and the recovery varies. In most cases, the sensation recovers completely or to a level that is not bothersome to the patient but in some, there may be significant numbness on a permanent basis. Fortunately, this nerve is purely sensory in function and as such, mobility of the lips are not affected. Due to possibility of a permanent morbidity, it is important that a patient who is comtemplating implants in the lower jaw understands this. Modern imaging techniques such as cone beam CT scans provide cross sectional and 3D images that can be measured to determine the appropriate size implants to minimize the risk significantly.
2. Implant failure
Dental implants are titanium screws that are screwed into bone, just like placing a wood screw into a piece of timber. However, the similarity ends there. Once inserted into bone, the dental implant elicits a certain response from the bone. The bone cells abutting the implant undergoes resorption first and then followed by new bone formation. This process typically takes about six weeks. During this healing period, overloading the implant or infection can affect the bonding of the bone and that may lead to the implant coming loose. In such cases, the implant will need to be removed, and a new one replaced.
3. Aesthetic complications
Today, dental implants are no longer replacing function. It is also expected to restore aesthetics in the front teeth. However, if the implant is not situated in an optimal position in the bone, the subsequent crown that sits on it may not look as aesthetic as it can otherwise be. This may be due to insufficient bone being available to support the implant in the optimal position. To achieve a good aesthetic result, additional procedures such as bone and gum grafting may be needed before implant placement to create an ideal base on which to site the implant.
There are many more potential complications that can happen in dental implant surgery. However, with advance planning tools such as CT scans and computer programs to plan and guide the placement of implants, complication rates can be reduced significantly. The skill and experience of the surgeon placing implants are also important factors that may affect the complication rate.