Combination syndrome is an oral condition in which you have serious bone loss in the front side of your upper jaw, which results in various changes in both your upper and lower jaw in terms of bone mass and density.
The condition was named so by Dr. Ellsworth K. Kelly, a Professor of Denture Prosthesis at the University of California, in 1972.
Dr. Kelly documented the changes that removable partial dentures on the lower jaw in 6 dental patients caused to their complete dentures on the upper jaw.
It was later described as a ‘complex pathologic condition of the entire stomatognathic system‘ by Dr. Len Tolstunov, Professor of Oral and Maxillofacial Surgery, University of the Pacific School of Dentistry, San Francisco, California.
The stomatognathic system includes the complex functions and structures of tissues and organs within the mouth.
In this article, we bring you 10 hand-picked points to give you a comprehensive idea of what combination syndrome is and how it is diagnosed and treated.
Combination Syndrome: 10 Solid Facts
1. Combination syndrome can cause serious bone loss
If you live with missing teeth for a long time, your jaw will not receive the pressure to maintain its bone mass. The result will be a severe bone loss – where you are missing your teeth and elsewhere within the mouth.
In other words, a prolonged period of tooth loss in one jaw will affect other parts of the jaw and the other jaw. The situation may turn so complex that you may need a team of dentists to make your mouth fully functional again, if at all possible.
Also read: How to replace a missing tooth?
2. Combination syndrome can reduce your chewing ability
The condition will affect your teeth alignment and your chewing habits.
You may soon find that you are using a certain number of teeth to chew your food more than others. You may even use only one side of your mouth to chew your food, withdrawing any pressure from the other side.
The result is bone resorption on that side and a gradually reduced capacity to chew food on your part.
Also Read: 14 Solid Facts About Transient Lingual Papillitis (According to Medical Experts)
3. Removable dentures need as much attention as your natural teeth
Now the question is: where does it all start?
Do you begin to lose bones because your dentures do not fit your mouth well?
Or, your dentures do not fit your mouth well because you are losing bones?
Dr. Kelly solves this confusion in his paper. ‘The most perfect denture,’ he writes, ‘will be ill-fitting after bone is lost from the anterior part of the ridge.’
4. Combination syndrome may require a robust treatment plan
Your combination syndrome treatment plan may include the following:
- Bone grafting
- Dental implantation
- Replacement of implants
- Tooth extraction
- Sinus augmentation surgery, or adding bone to your upper jaw to make it taller
- The application of local anesthesia
- Denture relining or rebasing
- Root canal
5. Combination syndrome has 3 classes
Based on the clinical and radiographic evaluation of a 76-year-old woman who complained of having difficulty chewing and speaking clearly, Dr. Tolstunov divided the combination syndrome into the following three classes:
- The upper jaw without any teeth
- The upper jaw with some teeth remaining on both sides at the back
- The upper jaw with some teeth remaining on one side at the back
Point to note: the classification deals with only the upper jaw.
6. Combination syndrome has 10 modifications
The modifications concern the condition of the lower jaw in relation to the three classifications of the upper jaw mentioned above.
The modifications can be the following:
- The lower jaw missing some teeth at the back on both sides
- The patient has a full set of natural teeth or implant-supported crowns or bridges on the lower jaw
- Teeth are present at the front side of the lower jaw and on one of its sides at the back
- Teeth are present (or recently removed) only at the front side of the lower jaw
- The patient has some teeth left at the front of the lower jaw and on one side at the back, but the teeth at the back do not come in contact with the teeth on the upper jaw at the back
- Similar to the previous modification, but the teeth, in this case, come in contact with those on the upper jaw
7. The treatment of the combination syndrome depends on several factors
Treating a patient with combination syndrome can be a huge challenge for a dentist. One of the reasons for this is that the success of the treatment does not depend on how the missing teeth are replaced but also on what the teeth present are doing to them.
For example, if you have some healthy teeth left on both the upper and the lower jaw, and they come in contact with each other correctly, the pressure on the opposite jaw will cancel each other. The condition will delay the growth of bone for implantation purposes.
The success of the treatment, overall, will depend on the following:
- You have or haven’t teeth left on your jaws
- You have a history of tooth loss
- Your teeth are in good or bad condition
- How long have you been living with missing teeth
- What kind of dental appliances do you use?
- The quality of your dental appliance
- Did you undergo dental implant surgery before?
- The density of the jawbone
- The presence or absence of bruxism
And many more.
8. Occlusal imbalance remains to be the topmost reason for the combination syndrome
If you have an occlusal imbalance (your teeth are not properly aligned), you may suffer from the following:
- Tooth wear
- Bone or gum loss
These conditions gradually push you towards the combination syndrome condition. The purpose of the treatment should, therefore, be focused on eliminating the occlusal imbalance.
That is where the reconstruction of the upper jaw or maxilla comes in.
However, dentists should make every effort to prevent any unfavorable combination of a complete denture for the upper jaw and a partial denture for the lower jaw.
9. The implant-supported denture treatment is a popular solution to the combination syndrome
If your dentures are implant-supported, and your teeth on the upper and lower jaws contact each other evenly, that will help the jawbones at the front to rest.
The chewing pressure will be distributed evenly across the backside of your mouth.
Frequent relining of ill-fitting dentures may temporarily slow down the progress of the combination syndrome, but it won’t stop it.
10. Replacing the missing teeth early is the best preventative method for the combination syndrome
Dentists recommend early treatment of missing teeth, so the condition does not aggravate into a combination syndrome.
The longer you live with your missing teeth, the longer your jawbone will continue to shrink.
Besides, wearing dentures does not apply enough pressure to your jawbones to end their bone loss.
However, based on your oral condition and treatment history, you may need a combination of treatments to control your combination syndrome.
Kelly, E. Changes caused by a mandibular removable partial denture opposing a maxillary complete denture. The Journal of Prosthetic Dentistry. 1972 Feb;27(2):140-50.
Tolstunov, Len. Combination Syndrome: Classification and Case Report. Journal of Oral Implantology. 2007; 33 (3): 139–151.
Tolstunov, Len. Combination syndrome symptomatology and treatment. Compendium of Continuing Education in Dentistry. 2011 Apr;32(3):62-6.
Colgate. Sinus Lift Surgery: Answering Common Questions. Accessed on 5 December 2022.
Carlino, Paolo, et al. Surgical and Prosthetic Rehabilitation of Combination Syndrome. Case Reports in Dentistry. 2014; 2014: 186213.
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