1 Prostho lec #6b : difficulties in complete denture construction & solutions Mon : 28\11\2011 Today we will continue talking about difficulties and solutions in constructing complete dentures. We started with tray size and selection and small mouth opening, retching, anatomical factors related to denture bearing area’s like: undercuts, flabby ridges, short upper lip, V shaped palate, spike ridge, flat ridge, high ridge. Most of the patients have reduced ridge height, especially in the lower arch, but some patients especially those who have teeth extracted due to decay not disease, sometimes the upper and lower ridge heights might interfere with the denture, so there will be no enough space for the acrylic base and teeth. In this case the ridge height will be causing difficulties in constructing complete denture. Usually it is limited interocclusal space, and you can't open it because lower face height will be increased, and sometimes you find that in part of the ridge, like for example, lower anterior segment, upper anterior segment, most patients have posterior teeth extracted before anterior teeth, because of decay, class 1 carries happen in pit and fissure. What’s the solution? If we can play a little bit with setting of teeth, make the acrylic base as thin as possible. Move teeth a little bit without affecting the neutral zone, sometimes it interferes with the prosthesis so you need to do surgical reduction. (osteoplasty) It's very common, in the upper anterior area, especially in patients where teeth are recently extracted, the bone would labially still not resorbed. Why is this area not important? Because if posteriorly if we push a little bit the cheeks it will not affect that much the esthetics but anteriorly if you ever stretch the lip it will be prominent and not acceptable esthetically. High ridge: Prominent ridge:
Transcript
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Prostho lec #6b : difficulties in complete denture construction & solutions
Mon : 28\11\2011
Today we will continue talking about difficulties and solutions in constructing complete dentures.
We started with tray size and selection and small mouth opening, retching, anatomical factors related to denture bearing area’s like: undercuts, flabby ridges, short upper lip, V shaped palate, spike ridge, flat ridge, high ridge.
Most of the patients have reduced ridge height, especially in the lower arch, but some patients especially those who have teeth extracted due to decay not disease, sometimes the upper and lower ridge heights might interfere with the denture, so there will be no enough space for the acrylic base and teeth. In this case the ridge height will be causing difficulties in constructing complete denture.
Usually it is limited interocclusal space, and you can't open it because lower face height will be increased, and sometimes you find that in part of the ridge, like for example, lower anterior segment, upper anterior segment, most patients have posterior teeth extracted before anterior teeth, because of decay, class 1 carries happen in pit and fissure.
What’s the solution?
If we can play a little bit with setting of teeth, make the acrylic base as thin as possible. Move teeth a little bit without affecting the neutral zone, sometimes it interferes with the prosthesis so you need to do surgical reduction. (osteoplasty)
It's very common, in the upper anterior area, especially in patients where teeth are recently extracted, the bone would labially still not resorbed. Why is this area not important? Because if posteriorly if we push a little bit the cheeks it will not affect that much the esthetics but anteriorly if you ever stretch the lip it will be prominent and not acceptable esthetically.
High ridge:
Prominent ridge:
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I have told some of you in jaw relation to make the acrylic base as thin as possible labially, but don’t leave a knife margin of the denture so you don’t cause trauma!
So usually we prefer acrylic to be 2 mm thickness but in this area we would prefer if it was 1 mm thick. If 1 mm was still thick for some patients we can do an open flange denture, cut the flange completely, it has many names sometimes they call it flangeless denture, open window denture, it doesn’t matter the idea is you don’t have a flange anteriorly, in the area of prominent bone.
What’s the consequence of having no flange anteriorly?
>> Loss of retention.
At the time the lip is contacting the borders of the denture, there is no problem, retention is there, and when you raise the lip a little bit, there will be loss of retention!
There is another thing with the patients that have class 2 div. 1 , we will teach you that with pre-prosthetic surgery, they will have proclined teeth, and mobility with decayed teeth, when they extract the tooth they will use Rongeurs forceps (do you know the bone cutters ?) removing the interseptal bone and creating grooves labially. It’s a simple procedure and this will retrocline the labial plate of the bone. So from the start we create an interception for the denture, where we move the bone backward, in this case class 2 div 1 its very significant , because its not only prominent bone, its PROCLINED bone. The good thing with patients that have class 2 div 1 , its no problem if you give them a denture with class 2 div 1
When the 3rd molar supra-erupts , the tuberosities follows. Sometimes even when we do extractions the tuberosities might do enlargements, it might be one of these two:
1) fibrous
2) Bony
3) Combination of 1 and 2
Don’t use only palpation! Sometimes when you palpate fibrous tissue might seem bony.
Large tuberosities:
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Now for large tuberosities when the patient just bites normal the patient tuberosity will bite on the ridges.
So no way that you can do complete denture for this case without doing surgical reduction or cutting of the denture!
Most patients would refuse surgery even though its simple surgery. Large tuberosities is in two dimensions, one is large vertically, one is large buccolingually.
Some patients would have very big large tuberosities buccolingually and severe undercut but the heights are fine. And others might have vertical tuberosities it will be fibrous tissue or bone, in both cases in surgery they will teach you how to do a surgery technique (wedge shaped) to reduce the tuberosity size. In cases where it's not severe enlargement we can do thin base acrylic where it doesn’t make any interference.
Some people say tuberosities is very important in complete dentures some of them think its primary stress bearing area and if it has mild to moderate undercuts it can aid in retention so in some tuberosities we relief or do surgical reduction.
Sometimes we need to relief the record block and when we do insertion for the frenum. What will happen if you don’t relief the denture for the frenum?
Sometimes things might happen straight away, for example as soon as you insert the denture the denture will dislodge. The frenum is a very friable soft tissue, most of the time it dislodges the denture, so when you leave it without relief and the patient comes for review you will see him with an ulcer. And it’s a very common mistake with students.
Just to remind you the labial frenum doesn’t move laterally so it should be just a slot. Buccal frenum on the other hand should be V shaped as it moves up and down, anterior and posterior.
How do you know if the patient has high frenum attachment? It might reach up to the embrasure between the teeth. So when you raise the upper lip you will see blanching of the papilla. So in complete denture there is no teeth and it will reach to the crest of the ridge. Usually we do a slot but if it was really high we will use a technique in surgery called frenectomy. Which has multiple techniques.
High frenal attachment:
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Especially seen in mentalis, in bad cases the labial surface of the ridge is sloped and the lower lip up to the ridge, and it's very tense so when you hold his lip you feel him resisting. This is usually because of tense mentalis or the modulus area.
In these patients the muscle is already pushing back, the best thing to do is make a concavity in the labial flange of the denture, and set the lower incisors as posterior as possible, keep in mind the neutral zone, tongue and lip! Also you should extend the lower denture as posterior as possible covering 2/3 to 3/3 of the retromolar pad area.
Also the occlusal plane should be below the tongue so tongue helps stabilize it.
Tempromandibular dysfunction and complete denture, there is no contraindication. Patient might have pain so he will not allow you to do centric relation in a proper way or he might have a problem in the TMD’s that create a deviation in the mandible so it will be hard for the operator to exactly locate the CR.
They will also have limited mouth opening, especially the ones with disc displacement without reduction.
It's very common to make a complete denture for a patient with CVA, most of them are hemi-paralyzed, so in these patients the control of the muscles in there face is hard.
Most old age patients has Parkinson's disease , and this disease affects the retention of complete denture. Some patients may also take drugs that cause xerostomia.
Now as for the behavior of the patient most of time it’s constructed for patients who are of old age, (above 50 or 60) so their behavior and communication skills is different. Also “you don’t know what you don’t know” à memorize this sentence. Most of you are around 22 years old, dealing with patients with old age who have different expectations and you are dealing with them with YOUR behavior, sometimes it works sometimes it doesn’t.
Tense muscles:
TMDs:
Systemic diseases behavior and communication: problems
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Even if you are a good student and work good with a good demonstrator , the final denture might still have a problem because of the communication, the patient might not come to try in!
So many patients has severe gag, and as soon as the demonstrator goes and see the patient instead of the student, the gag disappears we will take an impression without a problem! What will be the problem here? Communication problems
This is very important. Firstly we will discuss denture induced stomatitis, the other name for it is denture sore mouth, this disease is painless, patients rarely complains of soreness. Denture stomatitis has 3 clinical pictures classified by “Gretchen” (I am not sure) in 1962, as you can see complete denture science seems like an old science! Its common sense cause it was the only way to restore edentulous mouth.
So he classified it into 3 types:
Type 1: hyperemia associated with trauma from the complete denture
It's so easy to diagnose because as soon as you remove the complete denture JUST the area covered by denture is affected. Most of the time its upper , in upper jaw , because of the wide upper surface, from the posterior area of the vibrating line the area is normal, anterior to the vibrating line (place of denture) not normal.
Sometimes you might construct a denture that’s already rocking, and that’s during function, something that will cause trauma. And the people with flabby ridges during function will cause trauma, or people might have good denture but the problem is in occlusion and occlusion problems they cause the denture to move and rock à trauma.
So type one is associated with trauma from denture.
Hyperemia à you just see red mucosa. Usually its pinpoint
Oral diseases and pathologies:
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Type 2: generalized erythema.
All area covered by denture is red.
Both these cases are reversible (if you do a good denture, correct the faults, prescribe medications)
Type 3: you will see papillary hyperplasia
you will find enlargements. This is irreversible, they can be removed by surgery. You don’t have to remove them but sometimes you will need to because they will affect the support of the denture!
The incisive papilla may be enlarged, it happens in some patients, there is a problem if it gets enlarged too much some patients might get neuroma’s which is a benign growth of the nerve bundle. So sometimes they can get neuroma’s in the mental area, or incisive papilla area.
Etiology and treatment?
Etiology : most common cause from denture trauma. So when you see denture stomatitis you must examine the complete denture and adjust the defects or faults of the denture. Poor oral hygiene is the second cause, so both these causes are the MAIN causes for denture stomatitis.
The lesion is sometimes superimposed with fungal infections >>They found that pts
with denture stomatitis has candida albicans with higher percentage than normal
people," candida albicans is part of the normal flora in many people 30-60% " ,is it
the cause ? we don’t know! Bcz sometimes if u treat denture stomatitis with
antifungal, the lesion doesn’t go >> but they found that many pts with denture
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stomatitis has candida on the fitting surface of the denture and on the oral mucosa
>> as u know, fungal infections don’t happen in normal pts, it only happens in
immunocompromised pts >> this means that diabetic pts are at high risk to develop
denture stomatitis bcz of immune suppression and trauma.
Treatment:
The etiology determines the treatment:
>> if the cause is trauma, then the treatment is "ideally" adjusting the denture b4
jumping into constructing new dentures unless the mistakes are uncorrectable. In
this case u need to make new dentures, but remember u can't take an impression of
a diseased mucosa so:
>> u either ask the pt to completely remove the dentures and wait for the tissues to
recover or u use the tissue conditioner " visco-gel" which is a soft lining material so
that it reduces the trauma on the denture bearing area bcz it absorbs forces.
>>Then u adjust the occlusion : usually pts with old dentures have already flat teeth
with class III postural position of the mandible, u adjust them by something called
"occlusal pivots", this will bring back new vertical dimensions and new centric
relations with the existing dentures before constructing new dentures, then u make
the new denture fixing the old denture problems .
Poor denture hygiene >> this is common in 24-hour denture wearers >> always
advice ur pts to remove the dentures at night and to put them in 0.2 chlorhexidine
solution. Or they can use highly diluted bleaching agents " but these can even
convert the pink acrylic into white" . or they can use sodium hypochlorite highly
diluted >> the best are denture cleansing tablets, these are available in pharmacies
>> just one tablet in a cup of water is sufficient (these tablets r usually 0.2
chlorhexidine) >> pts should also buy soft brushes and "ideally" should brush them
after every meal under tab water " with water underneath to avoid denture
fracture if they were dropped" and brush the fitting, polished and occlusal surfaces
of the denture.
Antifungal drugs can be used : Nystatin , Amphoterisin, Miconazole "the most
commonly used" in gel form >> paint it on the fitting surface of the denture 3-4 X
daily. Be careful when prescribing Miconazole bcz if it is systematically absorbed, it
can cause severe side effects in pts under anticoagulant therapy.
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Surgery might be needed in some cases of type 3. Remember this : females "there is
female predisposition" & diabetics
Burning mouth syndrome:
The pts complain of a burning sensation " he exactly tells u : 7ass b nar in my
mouth!".
Differential diagnoses : denture stomatitis, but remember pts don’t complain of pain
in denture stomatitis. So the most important differential diagnosis is allergy to
acrylic.
You usually open the pt mouth but u can't see anything abnormal, or u see general
manifestations that aren’t specific to the syndrome like the tongue appearance
similar to iron-deficiency anemia
Etiology:
It is a psychosomatic pain, of unknown etiology.
Broad-spectrum antibiotics : these will kill the normal flora giving the chance to
opportunistic microorganisms to cause the burning mouth syndrome.
Fungal infections can sometimes cause the syndrome.
How to distinguish it from acrylic allergy? Simply when the pts wear the denture,
they will have the burning sensation and u can see the mucosa red and reacted to the
acrylic.
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Dry mouth:
Can be a pathology like in Sjoegren`s
syndrome or secondary to medications like the
antihypertensive agents that cause xerostomia
>> post-radiotherapy pts bcz radiotherapy
affects the salivary glands function
why this is important in complete dentures?
>>Adhesion cohesion:
>>Trauma: more important: saliva doesn’t only help in dentures retention, but it
also help in protecting the soft tissues from trauma bcz it acts as a lubricant. So what
are the consequences of reduced salivary flow?
>>Reduced retention
>>Trauma
>>Increased risk of opportunistic infections esp. fungal infections bcz of the lack of
the "wash effect of saliva " >>even patients with partial dentures and xerostomia will
develop rampant caries and can lose all the remained teeth in something like 6
months!"
U all know that u can clinically detect xerostomia using the dental mirror which will
stick to cheeks. Mucosa is wrinkled and dry and u can see ulcerations.
Dry mouth is a very awful sensation >> if u want
to try it: bring 5 tea biscuits and eat them at
once without drinking water :P !
Xerostomia is degrees " it's not as sever in drug
induced as in Sjoegren's syndrome"
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Management:
>>Synthetic saliva: most pts doesn’t like it!
>>Ask the pts to drink as much water as they can.
>>Chew gum! Esp. paraffin wax, of course this is in
case of functioning salivary glands!
Luckily and interestingly, implant dentistry isn’t affected by dry mouth bcz implants
don’t decay, and don’t need saliva for retention, so it can be a solution in pts with
xerostomia. The only problem is peri-implantitis
In all the 3 conditions : visco-gel is used to rapidly relief the pain >> it is an elastic,
almost transparent highly viscous material even when it sets >> most pts indicate
rapid relief after application of this tissue conditioner, it also helps to eliminate
infections if they are present. The problem with visco-gel is that it becomes hard after
one week, harbors a lot of plaque and can cause infection b itself!
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U need to understand that u might have a young pt,
These Pts usually have very difficult social life : ldrjt enno he ignored his mouth y3ni
he didn’t do any oral hygiene measurement bcz his mouth is the last concern or bcz
he is depressed, and bcz he is young and edentulous he is shy : bt$ofhm by6l3o ymen
w ysar lma yjo y$elo e dentures l2no ma bdhm any observer y$ofhm! >> so these pts
have the age as a main concern.
Old pts just want something to eat and to speak , y3ni they care about function and
aren’t concerned about appearance even if they have a canted occlusal plane!!
Now we will mention things that u might think are funny, but we face them in the
real life:
Some pts who are heavy smokers and their oral hygiene is the last concern get their
teeth extracted when they are in their 30s while they are still single! >> now when
these want to get engaged mst7eel yro7 bdon asnan :P >> they need CDs >> most of
them can't afford implants >> minimum number of implants in the DTC costs over
7ooo JDs >> hwe already ma m3o ytzwj , f ma balk ro7 yzb6 asnano b 7ooo! >> so hl
mskeen ma 9fa 2damo ela CDs >> CDs are solutions and nightmares at the same time
>> they don’t want their partner to know about the dentures >> this is cheating -.-!
>> this can lead them to separate! >> keep in mind : pt confidentiality is very
important!
Pts age and expectations:
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A practitioner working correctly can see his pt every week. "Ideally " one month is
enough for CDs. Students need one semester! Intervals shouldn’t be very long esp.
between 2ry impression and insertion bcz resorption is a continuous process esp. in
pts with recent extractions.
El mraf8en eli m3 el pt. bejek pt w jayb m3o el 3$ere : e$e 9`3er e$e kbeer e$e 3l
ymeen w e$e 3l $mal 8al e$ jayeen ytfrjo!! Behave professionally >> only keep the
escort if the pt is very old and he helps in communication with the pt. otherwise
dismiss them!
Laboratory technicians aren’t enemies! they are ur supervisors in the lab so plz
follow their instructions. In prosthodontics the relationship with the technicians is
very important: all the issues should be understood between us & them. It's an
equation and need both sides to fabricate good work .
Bad experience doesn’t necessarily means bad work , it might just be unrealistic pts
expectations. It can also be the opposite: y3ni el pt bjeblk 5 dentures & all of them
have mistakes that prevent pt satisfaction. How do you know the case? Examine the
dentures!
e.g., the 1st denture: very bad occlusion
2nd denture : bad occlusion & poor fitting
3rd denture: retention perfect, stability perfect, occlusion perfect >> in this case do
you think that if you make a new denture the pt will be satisfied?! No. u need to be
smart!
Appointments durations and intervals:
Communication with laboratory technicians and quality of lab work:
Escorts:
Pts having bad experience with complete dentures:
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U might have a pt with good dentures, but have complaints like worn teeth or loose
dentures >> in this case copy dentures is the treatment of choice.
Important note:
The exam material included from the 1st lec to the end of the difficulties lec NOT
