Rem pros Flashcards
What are some challenges may occur when natural teeth are lost
- Alveolar bone loss in extraction sites (no loading…)
- Remaining teeth can change position
- Tooth overeruption
- Changes to dynamic occlusal schemes
- Extra occlusal load on remaining natural teeth
- Changes to speech
- Changes to facial appearance
- Patients self-conscious with low self esteem
What does changes to dynamic occlusion mean
- Changes in contact: lateral excursion
- Sometimes associated with cause temporomandibular disorders
What can extra load on teeth do
- Wear them down quicker
- Push them into different position
What can occur in terms of changes in facial appearance in loss of teeth
- Reduced OVD
- Upper lip not supported
- Angular cheilitis
What is the purpose of a dental prosthesis
- Replace lost tissue
- Restore normal function
- Restores normal appearance
- Prevents undesirable effects: drifting, overeruption, tooth wear
- Fixed or removable
Why provide a denture and advantages
- Good for extensive tooth loss
- Sort of replaces alveolar bone
- Easily removed: sports/cleaning
- Reversible (flexibility in tx planning)
- Minimal alteration to natural teeth
- Less expensive
- Good temp option/ people who will loose more teeth
What are the components of a partial denture
- Saddles (hold artificial teeth)
- Rests
- Clasps
- Connectors (major, minor)
What are the disadvantages of dentures
- Removable
- Often less well tolerated by patients (bulky, uncomfortable, loose)
- Metal clasps visible
- Plaque traps (caries, perio)
- Ulcers/ pain underneath sometimes
- Needs maintaining (or replacing)
What is the concept of shortened dental arch
- Adequate function can be maintained with reduced dentition
- 9-10 occluding pairs of teeth
- Anterior and premolar should be in good health
- Upper and lower tooth contact should be favourable (avoid severe ortho malocclusion)
- Is significant tooth wear likely: bruxism, patient still young
Other than standard dentures what other types and why
- Onlay or overlay denture: replace part of teeth
- Transitional denture: more poor prognosis teeth
- Immediate denture: after an extraction
- Test (diagnostic) denture: restore function while teeth restored, check new jaw relationship)
- Obturators: hide holes in palate
Why is it important to do dentures in stable dentition
- More comfortable in healthy tissue
- Dentures last longer: extractions need denture change
- Denture can worsen caries and perio
What to do in denture related stomatitis (basic)
- Candida albicans
- Leave out at night, milton’s solution
- Keep denture clean
- Medication (nystatin, micanzole)
- Underlying cause investigation
What is and what to do in traumatic ulcer
- Denture border too long into sulcus
- Identify area with pressure paste: problem areas change colour
- Trim area back
- Temporary soft lining may help: visco-gel
What is denture granuloma
- Chronic inflammation
- Remove cause (denture related) or allow for inflammation to reduce
- Review
- Surgery if necessary
then take impression
Treatment or modification to improve denture function
- Tooth preparation for Cobalt chrome
- Tooth support for overdenture
- Tooth wear cases
- Placement of implant to help retain/support dentures
What are the tooth modifications for RDPs
- Guide planes
- Rest seats
- Unfavourable tooth surface recontouring (eg, altering survey line position)
- Occlusal adjustment (adjusting the occlusal plane)
- Creation of retentive undercuts
What is the definition of guide planes
- Two or more parallel (axial) tooth surfaces on abutment teeth which are used to restrict the path of insertion of a denture
What is the definition of path of insertion
- Path followed by the denture from its initial contact with the teeth until its fully seated
What are the advantages of guide planes
1) Control path of insertion of a denture
2) Facilitate easy insertion and removal of denture
3) Contribute to overall retention of the denture
4) Minimise wedging stresses on abutment teeth (lateral forces)
5) Reduce amount of ‘blockout’ (space between denture and teeth)
6) Aid denture stability (prevents movement during function)
What are the types of rest seats and what is it
- Provides vertical support for the denture
- Occlusal
- Cingulum
- Incisal
What are the functions of rests
- Transmit occlusal forces to the teeth along longitudinal axes
- Maintain correct occlusal relationship of denture base to abutment teeth
- Prevent trauma to gingival margins
- Provide some horizontal stability
- Prevent ingress of food between abutment teeth and denture base
- Act as indirect retainers as required (resist rotation and displacement)
When is occlusal adjustment of natural teeth necessary
- When rest seat preparation alone will not provide adequate space for rest or clasp
- To crease space for denture base/teeth
- To correct a natural tooth occlusal interference
- To improve the level of the occlusal plane
How can tooth undercuts be created for clasps
- Dimpling (remove a bit of tooth structure)
- Addition of composite
- Cast restoration (ideal contours can be created)
How are dentures held in place and prevents looseness(6)
- Saliva layer between the denture and underlying soft tissues can act as a ‘weak glue’ or help make a seal around a denture to give a suction effect (peripheral seal)
- Muscle of the oral cavity can press against denture surfaces keeping them in place (neutral zone)
- Upper and lower teeth can help keep dentures in place when patient bites together or chews food with no interferences
- Gravity with lower dentures
- clasps grip onto natural teeth (direct retention)
- rests can rest against natural teeth helping to prevent denture from rotation(indirect)
What if the denture flange is too thin
- Does not work as well to fill the width of sulcus
- No peripheral seal
What is posterior ‘post dam’ seal
- Junction between hard and soft palate
- Compressible tissue
- Near vibrating line, Fovea palatine
- Acrylic ridge extending there to create suction
What is the definition of support
- Resistance of a denture to displacement towards the supporting tissues (especially when subjected to occlusal loads on teeth)
What does complete denture support depend on (3)
- Amount of cover of underlying tissues or denture bearing area
- Condition/firmness of underlying tissues or denture bearing area
- denture fits supporting tissue properly
partial: rests allow force distribution
What is the problem with flabby ridge
- Fibrous underlying tissue: not very good
- Extremely mobile
- Implant, surgery, soft liners, denture design
How do you check the support of a complete denture
- Press down on occlusal surface and see if it moves or wobbles
- Look to see how much area is covered (extensions ideal?)
- Look for signs of trauma to tissues (imprint, inflammation)
What Is the definition of retention
- Is the ability of a denture to resist displacement away from the denture bearing area in a direction perpendicular to the surface of the tissues (whilst at rest)
What is the definition of stability
- Is the ability of the denture to resist movement in relation to the underlying bone during function (eating and speaking) (in any direction)
What does retention of a denture depend on (7)
- denture fitting supporting tissue properly (mucosa and teeth)
- Area covered by denture (denture bearing area)
- Adaptation of the denture to underlying tissues: correct flange extensions
- Border seal around edge of denture (suction)(peripheral seal)
- Muscular control by tongue and cheeks and polished surface suitable and only in neutral zone
- Gravity (lower)
- direct retainers (clasps) and guide planes
How to check denture has good retention
- See if moves when patient at rest (lip apart)
- Pull dentures away from supporting tissues (check tongue holding denture)
- Push anterior teeth and see if back drops
Clinically how can you assess where the posterior border is
- Look at colour change
- Foveae palati
- Palpate junction with blunt instrument
- Ask patient to say ‘aah’ and see where the vibration is
What affects stability of complete dentures
- **Degree of support available **
- Degree of retention available
- Area covered by denture base
- Degree of alveolar bone resorption
- Consistency of the supporting tissues
- Position of the teeth and design of ‘polished surfaces’ and only occupies neutral zone
- Correct vertical and horizontal occlusal relationship
- Freedom to make excursive movements
- Level of the occlusal plane
What 4 things maximise denture stability
- Good support
- Good retention
- Denture occupies ‘neutral zone’
- An occlusal scheme that avoids knocking dentures of place
How do you check the stability of a complete denture
- Patient history (denture movement during function)
- Press on occlusal surface (see if other part moves)
- Observe denture movement during speech or eating