Pros tutorials Flashcards
What is an occlusion?
A static relationship between the index teeth of a person dentition
What is the intercuspal position?
Maximum intercuspation of teeth independent of condylar position
What is retruded contact position?
Guided reproducible position where the condyle is in the most retruded position in the condylar fossa
What are index teeth?
Occluding surfaces of teeth in ICP
Why is RCP better for designing dentures when changing the occlusion?
- It is the most reproducible position
Why is ICP better for designing dentures when conforming to the current occlusion?
Using index teeth ensures denture construction will not change the occlusion
What are the ways obtain an inter-occlusal record?
- Wax records block - in free end saddles
- Bite registration
- Wax (modelling wax)
- Modified wax wafer (alminax)
When designing an RPD when will you require a record block stage?
- When replacing an index tooth (pre-molars and molars)
In what ways can you ask the lab to modify a wax record block?
- Finger rests
- Shellac base
- Metal wire strengthener
- Cocr base
How can you modify and improve survey lines?
- Etch and bond composite to increase undercut
What are precision attachments and what are they useful for?
Modifications made to intra-oral restorations or teeth which utilise certain components to increase denture retention
Give examples of precision attachments (2)
- Tubelock to teeth ( lock added in denture)
- Ball on post and diaphragm ( socket added in the denture for ball)
What are the challenges in precision attachements?
- Difficult to repair and replace
- Technically demanding
In some pateints localised periodontitis can cause significant tissue loss. Give 2 ways in which you will manage this?
- Alter path of insertion
- Use a two part denture
What are the indication for two part denture?
- When there is different paths of insertion
- When there is gross tissue loss
What are the components of a two part denture?
- Split pins on CoCr denture
- Acrylic slots on different path of insertion
When is a swing-lock denture indicated?
In Kennedy class 1 and 2 by using tissue and bone undercut under anterior labial sextant
What are the components of a swing lock denture?
- Hinge and lock
What are the challenges in a swing lock denture?
- Technically demanding
- Require excellent oral hygiene
Your patient has returned for a denture review appointment , complaining that their new complete denture fractured down the middle . They mention they have a headache and upon extra-oral examination, you notice **mild pain and hypertrophy upon palpating the masseter **
What major connector would you use for their new denture?
Buccal bar = buccally approaching major connector for posterior lingually tilted teeth
Your patient has returned for a denture review appointment , complaining that their new complete denture fractured down the middle . They mention they have a headache and upon extra-oral examination, you notice **mild pain and hypertrophy upon palpating the masseter **
What patient related factor has resulted in fracture of the denture?
Parafunctional habits = bruxism
Your patient has returned for a denture review appointment , complaining that their new complete denture fractured down the middle . They mention they have a headache and upon extra-oral examination, you notice **mild pain and hypertrophy upon palpating the masseter **
Give 3 features which you could incorporate into the new denture to reduce risk of future fracture?
- CoCr major connector with acrylic post dam - better reteion
- CoCr backing - reduce risk of fracture
- Crosslinked acrylic teeth - reduce wear resistance
Your patient has returned for a denture review appointment , complaining that their new complete denture fractured down the middle . They mention they have a headache and upon extra-oral examination, you notice **mild pain and hypertrophy upon palpating the masseter **
What is important to do before making a new denture for this patient?
** Manage parafunctional habit through: **
* Counselling (Education, home remediation, treat anxiety, psychologist referral),
* Medication - NSAIDs , TCA
* refer to oral medicine
What is retching?
Physiological mechanism involving involuntary contraction of muscles of soft palate and pharynx
What are the two types of retching and what can worsen it?
- Psychogenic
- Somatic
- worsened by anxiety
What are the triggers for psychogenic retching in dentistry? (4)
- Sight
- Smell
- Sound of dental instruments
- Thinking of impressions
What are the triggers of somatic retching in dentistry?
- Touching the trigger zones
What are the trigger zones that may cause retching? (5)
- Base of tongue
- Uvula
- Posterior pharyngeal wall
- Palate
- Pharyngeal folds
Give three management strategies for a retching patient
- Relaxation
- Distraction
- Desensitisation
Explain the relaxation technique to manage retching
- Passive - dim lighting , music and avoid sight of dental instruments
- Active - controlled rhythmic or relaxed abdominal breathing
- Combine this together to relax the patient
Explain how you would achieve the distraction technique to manage retching during jaw registration or impression taking (6)
- Talk to the patient
- Put salt on tongue
- Get patient to press or tap their temple
- Let patient close their eyes
- Rinse mouth with very cold water just before treatment
- concentrate on wiggling toes
Explain how you would preform desensitisation on a patient for impression taking to manage retching? (3)
- Repeated brushing or stroking of anterior palate or tongue with finger or toothbrush
- Homework for patient to brush or stroke anterior palate or tongue
- Swallowing with mouth open
What difficulties in prosthodontics may be associated with retching? (4)
- Impression taking
- Jaw registration
- Toleration of dentures
- Denture retention (as palate may be reduced)
What 3 changes can you make to the impression taking stage specifically to manage retching? (4)
- Modify stock trays
- Use lower trays in upper arch
- Modify special trays (palatal reduction)
- Mix alginate in warmer water - fast setting leading to less exposure time
What 5 denture design changes can you make to manage the retching patient?
- Buccal bar instead of lingual bar
- Gradually cutting back multiple post dams
- Thinner palatal coverage
- Rounded cusps on posterior lowers
- consider no second molars
Which retainer would you use for short term management retching?
Essix
What would you provide for a shortened dental arch that does not have sufficient units (3-3) or (4-4)?
- Implants
- Bridges
What is the most common reason of patient dissatisfaction in dentures?
- Poor retention and stability of lower denture
Which type of dentures are patients more dissatisfied with?
Partial
What factors make up effective communication in managing patient expectations before designing a denture? (6)
- Listen to patient
- Be empathetic
- Avoid jargon
- Answer questions
- Set realistic expectations
- Respect confidentiality
How can undertaking a thorough intra-oral examination help with managing patient expectations before designing a denture?
- Helps identify factors that can complicate denture design
- telling the patient about them to manage expectations
Give 5 intra-oral examination signs to look out for that may complicate denture design?
- Severely resorbed ridge
- Flabby ridge
- Tori
- Prominent mentalis, mylohyoid , Genial tubercles
- Pain on ridge
- High muscle attachments
What questions might you ask the patient to assess the risk of managing high expectations? (4)
- how long ago did you lose your teeth ?
- how many sets of dentures did you were ?
- how old is the last denture you had made ?
- are you wearing the last denture you had made?
Give some factors contributing to patient dissatisfaction with their dentures other than retention and stability of their lower denture? (4)
- Decreased chewing efficiency
- Aesthetic expectations unmet
- Facial aesthetics changed due to denture wearing
- Reduced self -esteem due to wearing a denture
Why can’t implants create the same proprioception as real teeth?
Because there is no PDL in implanted teeth leading to no physiological response to pressure
What 4 implant components that can be used to retain a denture? (4)
- Ball abutments
- Locator abutments
- Gold and titanium bar
- Screws
What are 4 post-implant treatment complications? (4)
- Peri-implant mucositis
- Peri-implantitis
- Infection
- Fenestration
According to SDCEP guidelines what is the role of a GDP in managing implant patients?
** Regular monitoring of implants **
* Baseline PA 1Y post-placement
* Baseline Periodontal pocket depth
* Tailored preventative advice to maintain good perio status
* Regular exams of peri-implant tissues
* PMPR
* Risk based recall
What is peri-implant mucositis?
Reversible inflammation of peri-implant soft tissues associated with an osseointegrated implant in the absence of cortical bone loss
What are the signs of peri-implant mucositis? (6)
- Increased pocketing
- inflamed mucosa
- Pain
- Tenderness
- Bleeding on probing
- Absence of bone loss
What is the management of peri-implant mucositis in GDP?
- Step 1 periodontal therapy
- CHX 0.2% for 7 days
What is peri-implantitis?
Inflammation of peri-implant soft tissue and hard tissue related to an osseointegrated implant with cortical bone loss
What are the signs of peri-implantitis? (7)
- BPE probes through epithelial barrier to alveolar bone
- Implant fracture
- Pain
- Tenderness
- Bleeding on probing
- Cortical bone loss
- Mobility
How to manage peri-implantitis in GDP?
Refer and grade based on clinical signs
Early onset - explant
Mild/moderate - Remove abutement and Step 1 (PMPR , CHX mouthwash)
Severe - remove abutement, surgical access , Step 1 perio (PMPR) , AB ± surgery
A patient have a natural lower dentition with a complete upper denture
How can this cause issues with in the upper maxillary edentulous ridge?
- High forces directed on anterior area of edentulous ridge causing rapid alveolar bone loss that is replaced with fibrous tissue due to response to trauma
A patient have a natural lower dentition with a complete upper denture
What are the consequences of this?
- Trauma to soft tissues
- Flabby ridge formation
What 2 issues are associated with a flabby ridge?
- Tissue displaceability
- Tipping of denture
Give 3 ways in which you can reduce the rate of a flabby ridge?
** Maximise stability by **
* mandibular posterior extension support and good peripheral extensions
* Effective post dam and posterior seal (upper)
* Maximise palatal coverage
* Use Overdenture abutements (retained roots or implants)
A patient has a complete upper denture opposed by natural lower anterior teeth with no posterior, leading to an ** increased overbite ** reducing the denture stability
Give 2 management options for this?
- Reduce incisal edges of lower teeth
- Reposition the upper denture teeth higher up
A patient has a complete upper denture opposed by natural lower and posterior teeth. The lower teeth have have an **irregular occlusal plane where the teeth do not have even contacts in ICP **
What issues does this cause for the stability of the upper denture?
Displacement of denture upon eccentric movements
A patient has a complete upper denture opposed by natural lower and posterior teeth. The lower teeth have have an **irregular occlusal plane where the teeth do not have even contacts in ICP **
How would you manage this? (4)
- Accept and monitor
- Use of overlay appliance
- Extraction of posterior teeth
- Minimal or major localised occlusal adjustments
A patient have a natural upper dentition with a complete lower denture. There is an irregular occlusal plane
Why is this much harder to manage compared to upper denture opposed by natural lower teeth?
- Less available physiological tissue for support
- High forces directed onto lower ridge
- Leading to pain and significant trauma to lower ridge
A patient have a natural upper dentition with a complete lower denture. There is an irregular occlusal plane
How can this be managed? (2)
- Soft liners ( Palliative as may need constant reliners)
- Impant retained lower complete dentures
According to kelly (1972) how does combination syndrome occur? (5)
** Maxillary denture is opposed by natural anterior mandibular dentition which is said to cause **
* Bone loss from anterior part of maxillary ridge
* Hypertrophy in the tuberosities
* Papillary hyperplasia in the hard palate
* Extrusion of mandibular anterior teeth
* Bone loss under denture base
Give 5 common types of denture fractures?
- acrylic tooth detachment
- midline fractures
- flange fractures
- clasp fracture or bent
- acrylic saddle detaches from Cocr base
Give 5 common reasons for denture fractures?
- Bruxism
- Dropping
- Thin section of acrylic
- Work hardening failure
- Denture processing problem - porosity
- Soft linings
How would you fix a fractured flange?
- Impression with denture in situ + standard impression
- Send to lab with denture
- Return and fit
How would you fix a fractured denture?
- If all fragments can be located
- Disinfect and send to lab for repair
- no impression is needed
How would you fix a lost acrylic tooth? (2)
- Reattach with self-cure acrylic or -
- Match shade and trim new acrylic tooth and set with self-cure acrylic
How can you repair an acrylic-cocr denture? (3)
- Solder on retentive tags
- Use 4-meta or silicoat to retain acrylic on Cocr
- If need to fix quickly (temporary) = self-cure acrylic or superglue
In what way can you strengthen denture repair? (3)
- Wire mesh
- Glass fibre mesh (in bruxists)
- Stainless steel wire in lowers
What types of dentures are additions for?
Partial dentures only
What is an immediate addition?
When a tooth is lost after denture construction & tooth added on the day of tooth extraction
Give an example of an immediate addition?
- Post-XLA immediate single tooth addition to existing RPD
Give an example of a post-immediate addition?
- Post-XLA after socket healing
- Take impression with denture in situ
- Send to lab
Give an example of a retention addition?
- poorly retentive RPD
- impression in situ
- send lab for addition or SS wrough wire
When denture retention is inadequate a clasp is added to try to improve retention
What are the advantages of acrylic? (4)
- Aesthetics
- Cheap
- Technically easy
- Easy to add to, reline or repair
Why is it not possible to repair flexibe dentures?
Due to weak bonding between acrylic tooth and nylon
What is the disadvantages of acrylic? (5)
- low impact resistance and strength - needs to be thick
- poor resistance to fracture fatigue
- Water absorption and candida growth
- Allergies
- Risks to technicians
What does acrylic consist of?
Powder
* Polymer - PMMA beads
* Initiator - Benzoyl peroxide
* Pigment - organic dyes
** Liquid **
* Monomer - MMA
* Crosslinking agent
* Inhibitor - hydroquinone
* Activator - only in self cure
What is the difference between relining and rebasing?
- Relining (done chairside) = adding material to the base of denture to fill space between denture and altered tissue
- Rebasing (done in lab) = replacing the entire acrylic baseplate
Give 3 reasons for providing a temporary reline?
- immediate denture no longer fits due to bone resorption
- Tissue conditioning = aid healing in inflammation
- After implant surgery
In which 2 types of patients would we use a soft temporary reline?
- Bruxists
- Cleft patients (obturators)
What risk can a soft lining pose?
Highly susceptible to candida bacteria
Give 3 reasons for providing a permanent reline?
- Issues with peripheral seals
- Post-immediate denture
- prolong lifespan of previous denture
Give the clinical steps taken to rebase an upper denture that is loose? (5)
- Use acrylic bur to remove undercuts from denture
- Take a ** wash impression using the closed mouth technique**
- Send to lab (asking for rebase)
- Disinfect
- re-insert and review within 1-2 weeks
How can milled crowns be useful in denture design?
- Can be modified to provide greater denture retention
** with ** - guide planes (parallel preps)
- undercuts
- rest seats
How to avoid single teeth saddles?
Anterior bridges combined with denture
What are some pathological changes than can affect dentures? (8)
- MRONJ/ORN
- Denture stomatitis
- Candida
- Aphthous ulcers
- Denture hyperplasia
- Flabby ridges
- Paget’s disease
- Allergies
Patient presents at denture review with an ulcer at the upper right maxillary tuberosity. How do you manage this?
- Paint pressure indicator paste over area of ulceration
- Seat denture and adjust area using straight handpiece
- Polish
- instruct the patient on HSMW for 3 days
The patient returns after 3 weeks and the same ulcer is still present. What could this indicate and what should you do next?
- Refer urgently to maxfax as it may be malignant
A new patient presents to you with denture stomatitis. What are 2 different management strategies for this?
** Provide denture hygiene instructions **
* take dentures out at night
* clean with soft bush and soapy water
* consider daily rinse
** may prescribe antifungals **
** investigate MH **
* haematinics
* diabetes
What is the aetiology of angular cheilitis?
- Diabetes
- Anaemia
- immunosuppression
- poor lip support
- Candida or strep
- low OVD
How does denture hyperplasia happen?
- overextension denture border
- leading to chronic irritation of sulcus
- leading to ridge resorption
- leading to fibrous tissue replacement
How to manage denture hyperplasia? (3)
- Trim flange and apply tissue conditioner
- review and repeat
- make new denture when tissue shrinks back or to oral surgery for excision
Can a bisphosphonate/radiotherapy denture wearing patient be at risk of MRONJ?
Yes
What denture materials can be related to allergic reactions?
- PMMA
- Nickel from CoCr
What is the difference between the effects of CoCr and acrylic denture on periodontal destruction?
CoCr less periodontally destructive
What is a key aspect of RPD major connector design to maximise periodontal health in a periodontitis patient?
- Reduce tissue coverage (less gingival tissue)
- Use lingual bar connector
What are 3 key teeth for retention and support to keep in dentures for periodontitis?
- Last standing molars
- Canines
- Premolars
- Periodontitis patient with lower bilateral free end saddles presents to you
- You judge that the remaining teeth are of very poor prognosis and the patient will likely need a complete lower denture within 6 months
What can you offer the patient in the meantime and why? 3 reasons
- Lower acrylic RPD
- Easier transition for patient to edentulism
- Reduce the mobility of anterior teeth
- Reduce rate of flabby ridge formation
What are the advantages of providing no prothesis in periodontitis patients?
- Better hygiene
- Less priodontal damage
Disadvantages of providing no prothesis to periodontal patients with free end lower saddles?
- Lack of posterior support lead to increased mobility of remaining teeth
- Lack of denture wearing experience making it hard to transition
What is the difficulty related to dentures in periodontal disease patients? (4)
- Impression taking
- Fitting Cocr denture
- Path of insertion
- Positioning denture teeth
What medical problems can be related to dentures? (6)
- Xerostomia
- Anaemia
- Frality
- Tremors
- Anti-resorptive medications
- Dementia and capacity issues
What is the aetiology of xerostomia?
- Dehydration
- Drug induced
- conditions : Sjogren’s , Sialosis , HIV , cancer treatment
- Trauma
- developmental deficiency of acinar tissue
What might be the consequences of xerostomia related to dentures? (3)
- Poor denture retention
- Candida infections
- Traumatic ulceration
What is the aetiology of anaemia? (5)
- Poor intake of Fe / B12 / folate
- Increase blood loss through menstruation or internal bleeding
- Leukaemia
- Reduced Hb production
- Increased Hb loss
What are the consequences of anaemia that might affect dentures?
- Recurrent apthous ulcers and other conditions irritating the mucosa
- Angular cheilitis
- Immunosuppression leading to infections
What are the types of anti-resorptive drugs? (3)
- Bisphosphonates - Alendronic acid
- RANKL inhibitors - Denosumab
- Anti-angiogenics - Bivacizumab
What is the risk associated with anti-resorptive drugs?
- MRONJ
How to manage someone with risk of MRONJ who wants dentures?
- Retain the teeth if possible to prevent the risk and provide overdentures with roots in situ
Causes of tremors? (3)
- Parkinson’s
- Huntington’s chorea
- Strokes ( cerebral vascular accident)
What denture related issues might be associated with tremors?
- Achieving RCP in jaw registration
- Issues with taking impressions
- Insertion and removal of dentures
- Need simple treatment plans - use cuspless teeth
What is frality
- Vulnerability after a stressor event due to poor resolution of haemostasis
What are the characteristics of Frality? (3)
- Reduced strength
- Slow walking speed
- Low energy
Can be associated with multiple long term conditions
Associated with multiple hospital admissoins and care home addmision
What is the difficulty related to dentures in patients with Frality?
- Difficulty to tolerate complicated treatment
- Better to provide replica dentures instead of making a new denture
What is dementia ?
Umbrella academy for disorders or conditions characterised by a decline in memory , cognition and language making everyday activities difficult
What is the name of the ACT associated with people that have dementia?
- Adults with Incapacity Act 2000
What is AMCUR?
** Factors of identify capacity to consent **
* Acting
* Making a decision
* Communicating the decision
* Understanding the decision
* Retaining the decision
What are the principles of adults with incapacity act? (5)
- Patient benefit
- Minimum intervention
- Take into consideration patient wishes
- Consult relevant others
- Encourage residual capacity
Who can consent for dental treatment on behalf of a patient who lacks capacity to consent? (4)
- Combined power of attorney
- Welfare power of attroney
- Welfare gaurdian
- Dentists who have completed training to complete section 47 of AWI
What are some basic questions you could ask to assess patient capacity? (4)
- What is this place?
- How old are you ?
- What is your date of birth?
- What year is it?
What dental issues might arise with patients with dementia? (4)
- Ability to consent
- Remembering appointments
- Remembering instructions
- Manual dexterity
What details should dentists include in section 47 when treating patients with lack of capacity? (4)
- The lack of capacity
- The proposed intervention
- Who they have consulted
- That the Act principles has been observed
Who are vulnerable adults?
- Adults that cannot safeguard their wellbeing, properties or rights due to physical or mental disability who are at risk of harm
What act is there for vulnerable adults?
Adult support and protection Act 2007
Give some examples of Adult support and protective services ? (4)
- Social services
- GP
- Police
- Indemnity organisation
According to the 3 point test in the ASP act, an adult is at risk of harm is one that ..?
- Unable to safegaurd their wellbeing / property
- Is at risk of harm
- Because they are affected by disability
