intro to partial dentures and patient assessment Flashcards
what patients are likely to have missing teeth
head and neck cancer patients
what percentage of the population don’t have all their teeth
60%
what are reasons for missing teeth
- caries
- periodontal disease
- endodontic infection
- trauma
- congenitally absent
in 2009 what was the average amount of sound and untreated teeth in Scotland
17.9
anatomical consequences of missing teeth
extra-oral *change in facial appearance *TMJ problems intra-oral *alveolar resorption *tooth movement *toothwear
what happens with alveolar resorption in tooth loss
- normally the teeth and the alveolar bone fill out the face, but if missing teeth then the denture must now do this
- lack of pressure on the bone cause resorption
- particularly in the mandible
- maxilla goes back with bone loss and mandible gos forward (class 3 - sunken face)
what happens to tooth movement with tooth loss
teeth can start to grow into empty spaces from opposing arches or on the same arch and can move/tilt
- causes problems with biting
aesthetic consequences of missing teeth
loss of hard and soft tissues which support the face
functional consequences of missing teeth
- mastication - soft diet needed possibly, depending on how well they can chew
- speech
- psychological - some patients can’t cope with the loss of their teeth and don’t want dentures (affects quality of life)
how to replace missing teeth
- resin bonded bridgework
- conventional bridgework
- implant crowns
- implant bridgework
- complete dentures
- removable partial dentures
what is resin bonded bridgework
- cna have medial cantilever
- retainer attached to abutment tooth
- Pontic then attached on messiah side of this abutment tooth
- probably most successful
- can have fixed-fixed
- a Pontic between 2 abutment teeth with retainer attached
what is an abutment tooth
a tooth which something rests on
what is a Pontic
a fake tooth
what is conventional bridgework
- more destructive to tissues
- like doing crown prep
- can have cantilever or fixed-fixed - retainer is a fixed tooth that slides over and sits on abutment tooth
what are implant crowns
- implant goes in the bone
* implant crown screws on to top of implant abutment
what is implant bridgework
- 2 implant abutments are screwed into bone with missing tooth in the middle
- implant crowns are on either side of Pontic (all attached) and crowns screw onto abutments
- material is easy to take off incase there is any problems
what are complete dentures
- removable dentures - no attachments for stability
- implant retained denture - snaps into place, some teeth on denture will sit on implants
- implant supported dentine - screw retained, non-removable
- removable partial dentures
what are the advantages and disadvantages of removable partial dentures
Advantages - less expensive -removed for cleaning -minimal tooth prep replacement of tissues possible Disadvantages -clasps unattractive - can cause gagging - retention and stability problematic
what are the advantages and disadvantages of fixed partial dentures
Advantages: - natural appearing - better stability - not easily removed - minimal sot tissue coverage Disadvantages: - expensive - suitable for short span - lots of tooth prep required
what is a saddle
area with no teeth
- can be free end or bounded
what is a rest
makes tooth supported
- can have occlusal or cingulum
what is a major connector
baseplate
- holds whole denture together
what is a clasp
attached to the abutment tooth
what does the WHO say about missing teeth
if the premolar region is intact and there is at least 1 pair of occluding molars then masticatory efficiency is not affected
what people are likely to have missing molars
those with sever periodontal disease
what is a shortened dental arch
- dentition where most posterior teeth are missing
- satisfactory oral function without the use of RPD
- priority given to maintaining an anterior and premolar dentition in one or both arches
- in some circumstances, don’t need to replace posterior missing teeth if there is a stable dentition
what is occlusal stability determined by
*pdl support, number of teeth in arches, interdental spacing, occlusal contacts and tooth wear
what typically occurs if there is one or more tooth missing in an arch
tooth mobility, tooth migration and supra-eruption of unopposed teeth
what is sufficient adaptive capacity
when there is 3 to 5 occlusal units left
- pair of occluding premolars = 1 unit
- pair of occluding molars = 2 units
how can you extend a shortened dental arch
- bridgework - max one unit on each side of arch, minimal contact in excursion, heavy contact may lead to failure
- implants - single tooth, can be cantilever or fixed bridge
- RPD - bilateral free end saddle (most common)
when is a patients occlusion considered stable
if they can achieve a reproducible ICP
- achieved by most patients with at least 10 occluding pairs of teeth
what are the 3 types of support for removable partial dentures
- tooth borne
- mucosa borne
- tooth and mucosa borne
what is tooth borne support
everything rests on the teeth
- no free end saddle
most desirable as doesn’t rest on tissues
what is mucosa borne support
everything rests on mucosa, none on teeth
what is tooth and mucosa borne support
mixture of rests on teeth and mucosa
what is the material (base) of RPD’s
- acrylic (pink)
- cobalt chrome (metal)
what must be included in the history taking of patient for RPD
- need full denture history (how many, how long, what kind, preferred)
- need full medical history (identify problems that could affect treatment)
- need social history (distance travelled to practice, ability to attend, hobbies - musical instrument -, smoking, alcohol, diet)
what problems could affect treatment
- arthritis
- neuromuscular
- mucosal diseases
- xerostomia (makes dentures rough feeling)
- osteoporosis
what must be included in the patient exam
- extra-oral
- lower facial height
- nasio-labial angle
- opening - how far? (enough for impressions)
- any abnormalities
- smile line
- aesthetics of existing dentures
- intra-oral
- general examination (perio status, endo status, caries, toothwear, indirect restorations)
- edentulous spaces (missing teeth, number, position, length)
- occlusion (contacts)
- missing teeth classes for saddle
what are the missing teeth classes
- Kennedy Class I - bilateral free end saddle
- Kennedy Class II - unilateral free end saddle
- Kennedy Class III - unilateral bounded saddle
- Craddock Class I - saddles supported on both sides by substantial abutments
- Craddock Class II - vertical boring forces resisted entirely by soft tissue
- Craddock Class III - tooth supported at only one end of the saddle
what must the dentures be examined for
- support - resistance to vertical movements of the denture towards the tissue
- retention - resistance of the displacement of the denture away from the tissue
- stability - resistance to horizontal movement of the denture
- aesthetics
- extension
- occlusion
- material
- design
- condition of teeth and base
- health of denture bearing area (denture stomatitis?)
- abutments (choose best teeth)
what special investigations are done
for abutments:
- periapcial radiographs to ensure teeth are adequate
- sensibility testing (EPT or ethyl chloride)
what are some diagnosis given to the patient
- endodontic
- periodontal
- caries
- toothwear
- shortened dental arch
- combination syndrome - when have full upper denture and partial lower and so you have no teeth in one area to know how hard you are biting as no PDL (cause bone resorption)
what can be some denture problems
- over/under extension
- reduced support, retention and stability
- fractured clasps/baseplate
- no freeway space
- poor aesthetics
- worn teeth
how should the treatment plan be made
discussed with the patient for the best solution
