When to reline/modify vs when to remake a denture

For some reason, I had a long period of no denture cases coming in. For maybe 1-2 years I did a couple of fractured denture repairs but no new denture cases. Lately there have been some new ones coming in which have been enjoyable to work with. I thought I would make a post regarding modification vs remaking of dentures. Of course by modification I don't mean something simple like adjusting a denture sore spot, where we obviously wouldn't remake a denture, but for where there is a significant discrepancy between what the denture should be like and what it is like e.g changes to the fit or teeth.

One common dilemma when a patient comes in with an old set of dentures is do we do nothing, do we try to improve the current denture, or do we start again and create a new set for the patient. My take on this is simple, if I can make an improvement to their current denture and this improvement will make a significant difference to the patient then it is justifiable to do something for them. This means that there is likely an issue with the denture fit, teeth or occlusion, or the patient has a complaint about their current denture that is attributable to a deficiency in the denture's design. For the latter point, there are patient who will just never have denture success. Their oral environment is unfavourable, dry mouth, no ridges, poorly active muscles. Or their personality is unfavourable with high expectations, lack of adaptability or lack of motivation. This is the best time to do nothing, be honest with the patient and refer the case. For some, they will catch you unawares, where their dentures have significant design drawbacks and you think you can make an improvement but their personality is also unfavourable. These you will have to figure out carefully or just take the hit when the failure inevitably comes. 

For those who we decide to proceed with treatment for, we ask ourselves, do I have to remake a denture, or can I modify the existing dentures to improve the situation. This comes down somewhat to logistics but mainly to what the actual issue is with the denture and how much work it is to resolve it vs the cost (in terms of money and time) or remaking the denture.

Logistically, if the patient can't afford a new denture and can only afford a modification, then as long as the modification will give a reasonable result and the patient is understanding of the limitations then the choice is easy. Just modify. If they need something done quick, maybe modify, because a reline or tooth modification will generally take one or two appointments and will be done within a couple of days. If for some reason, the patient cannot be without their dentures for a single second, potentially modification won't work if it requires sending to an external lab for any period of time.

Ok, so we have a patient in the chair and are assessing their dentures. This may be a new patient examination or an existing patient who has come for their regular check up or with a denture concern. Common issues patients will complain about are loose dentures, painful dentures, food packing under the denture. When I assess a dentures, on a fundamental basis, there are two aspects that matter: The fitting surface and the occlusion. 

The fitting surface then comprises of the peripheries of the denture and all the internal area. If there peripheries are under extended, then the support of the denture is less, perhaps there are sore spots from stress concentration during function, perhaps there is food getting under the denture due to a lack of peripheral seal. If the denture is over extended, then commonly there will be sore spots from the denture pushing into unattached mucosa or a lack of retention as the border muscle movements with flip the denture around. If it is a partial denture, these shortcomings may be less obvious as there are teeth to support and retain the denture but they are still important. If there are pressure spots in the internal surface of the denture, sharp spots of acrylic, these ares can easily be adjusted after being located with a fit checking material. If the peripheries are overextended, these can be adjusted with a bur and underextended peripheries can be corrected with a denture reline. If there is a major fit discrepancy or if the reline will move the occlusal surfaces of the teeth into an unacceptable position then you may be leaning towards a full remake as there is a lot of work to do to make the denture into an acceptable condition and there are a lot of factors that you need to control which increases the risk of treatment failure. 

The occlusal surfaces of the denture are formed by the teeth and here, we may find any number of issues. The teeth form the aesthetic as well as the functional component of the denture. If the tooth size or position is incorrect, we can make minor adjustments or remove and replace some teeth. If the occlusion is off e.g there is a poor functional relationship in centric occlusion then minor adjustments can be made. If  there are major changes to the occlusion then you may consider a remake. Essentially if I am reestablishing the anterior as well as the posterior occlusion it is probably better to do a remake. If the aesthetics is acceptable and I need to change the posteriors e.g due to wear, or if the posterior occlusion is spot on and the patient wants to change the anterior tooth shape, shade etc then I have no trouble in suggesting a denture modification over a remake.

If everything is just off or the patient just wants a new denture or you don't want to risk modifying their existing denture, then perhaps consider a remake. Especially those patients who have poorly fitting, worn down dentures for long periods of time and think their denture is the best, you do have a higher risk of having a poor outcome even with a technically better fitting, better looking denture.  

When I am not sure what the problem is, or I am unsure if addressing a denture problem will result in success, I like to try a provisional solution to see if the patient can tolerate the change. This is no different to provisional crowns or veneers to see if the patient can tolerate a vertical dimension change or an aesthetic or phonetic change in a dentate rehabilitation. 

Provisonal modification of the occlusion can be done in acrylic resin or composite resin. I generally use expired composite. If there is an aesthetic change the patient is wanting, I can mock up different shaped teeth, add length to teeth or overlay a different shade just like I would with a chair side tooth borne mock up. If the patient approves it, I can send the dentures off to the lab and get them to choose a set of teeth that match the mock up and they can change them over. If I am looking at changing the posterior occlusion, generally it is for a patient who has uneven contacts or worn posterior teeth so there will be space to add composite resin to even up the occlusion. Remember, we are aiming for bilateral even contacts in centric occlusion. This is easy to achieve with composite resin additions. If I have a sandblaster handy, I will sandblast the tooth surface, apply etch, bond (preferrably a universal bonding agent) and put a sausage of composite along the tooth surfaces I want to add to. Then I will place the denture back in, get the patient to bite together. If the composite needs more height I will squeeze the sides of the composite sausage to raise it higher. Once I see indentations from the opposing arch, I will remove the denture and thoroughly cure the composite. The case below will give a clinical example of this.

The following patient has upper and lower cobalt chrome based partial dentures for a number of years and has been complaining lately of soreness to the lower right lingual area. I applied fit checker paste to the area in question and found no localised pressure spots.  you can see that there is a lack of tooth support on the lower denture with no rest seat on the lower right first premolar and the rest seat on the lower left first premolar not contacting the tooth. The force from the lingual plate and the lack of posterior support has consequently led to flaring of the anterior teeth which is evident in the gap between the denture base and the tooth surfaces. Here, ideally we are looking at a remake of the dentures as the denture base is not easily modifiable to make the denture function acceptable.

 

 

However, I do need to assess these dentures to see what is causing the patient's main complaint and to gauge whether or not I can make an improvement with a new set of dentures. When I assess the occlusal relationship I can see a pretty significant posterior open bite. Why did this happen? I have no clue. The denture teeth are worn so they were in function at some point. I can only guess that there has been some residual ridge resorption more on the left side which has led to the upper and lower dentures sinking down further on that side. However, what this means for the patient's function is that they are not able to chew properly on the left side and when chewing on the right side there will be tipping forces that cause uneven pressure on the right side ridges. In the upper, there is sufficient support from the palate to resist movement so the patient feels discomfort at the weakest link which is the lower right soft tissues.   

To test out if improving the occlusion would improve the denture, I added composite on the left side of the lower denture to fill in the space. I didn't have a sandblaster handy, so I roughened the tooth surface with a bur, bonded the surface and added the composite. The patient noticed an immediate improvement in the feel of the dentures and had no sore spots after this appointment. If the denture bases were well fitting and properly designed, I would proceed to change the teeth over to new denture teeth at this new bite. As the dentures are poorly designed and ill fitting, we will proceed with confidence to provide some new dentures with an improved design, proper tooth support and occlusion. 

 

I will make another post about the temporary modification of the denture fitting surface to test if improvements there will lead to an increase in success of the denture.