Denture revision notes! Flashcards
Primary impression
prealse pour upper the upper and lower alginate impresions in 0:50 stone and provdie spical trays
upper - 3mm space non perforated llight cured acrylic resin trya with extra olral handles
lowers - close fitting light cured acrylic resin tray with extra oral handles
master impressions
please pur up the scondary impressions in 100% dental stone
please provide wax record blocks on light cured bases
Jaw reg
please mount the casts to the hreg providied
lease provide try in of wax teeth
mould and shade
detail in specal features
Tooth trial
please wax up for finish in heat cured acrylic
Denture hyg
please remove denture at night and soak in water
do not soak in boiling water as can distort denture
please clean over a bowel of water to prevent damage if dropped
clean denture after ever meal]may impinge on speech adn salivation
may get intial discomfort and pain
lceanwwith a soft bristle brush adn imild soap or denture cleaners not toothpaste
if yuing dental dhesvie then small amount and removed everyday
if denture becomes sore and can’t wear then wear 24hrs before appt to allow dentist to see sore aras
routine dental check ups 1year
Denturec leaners
alkialine peroixe - sterodent - hardens soft linings
alkaline hypochloritres - milton -only use for 10mins
ezymes - proliners - expensive and bleaches acrylic
abrasive cleaners - denturecreme abrasive - smokers
Attwood classification for boneresoprtion
class I - dentate - the area before xtraction of tooth from the socket
class II - post xla - tooth as just been removed from socket, bone deposition has started to form, edges sharpened
CLass III - broard avloear process - bone deposition continues and no reduction in height
Class IV - knife edge avleoar process - the alveolus shape starts to thicken into a knife edge appearance
Class V - flat ridge - resoprtption starts to occur creating a flat ridge
Class VI - submerge ridge - the alveolar bone starts to resprp into the basa lbone
Primary impressions
supplies a negative impression of the tissues in the mouth
becomes a positive impression when cast in dental stone
uncercuts - alginate
no undercutes - use non elastic impression compound
chec for - perheral seal, voids, tears, air bubbbles, surface detaail, extension to post dam, flange depth adn sulucs captures, denture bearing areas
MAster impressions
provedes a more accurate impression of the mouth
allows good functional depth adn width of sulcus to be captures with border modelling and muscle trimming to provide good perpiheral seal
occlusal stops - upper = canine and post dam, lower = retromolar pads and ridge of canine area
Jaw reg
LIMBO
lips
incisal lvel
mid line
buccal corridor
occlusal plane
shade
moulde
special features
jaw red
Tooth trial
check for extention retention, stability, aesthetics ,spreech, freeway space, denture bearing areas, present of post dam for retetnion, occlsuion, perpiher extentions
Delivery
repeart same steps carried out at tooth trial
provide denture hyg insutrctions and review in 1week
Why dentures fravture
trauma and impaction
thina crylic surface
work hardening on metal
bruxists pts
deep overbite
use of soft linings
advatanges of acrylic
cheap
good aethetics
easy to use for technicina
can allow relines and rebases
ca`nall allowaddiotoin of teeth
disadvatagnes of acrylic
allergy ot monomer
fracture resitance is decreased
denture whitening
can absorp wter easily
risk of caindial infecitons
impact strength reduced
disadvatnages of immediate dentures
gross irregularties ofteeth make processing dififcult
requires good co-operation from pt as need review appts
alveolar bone resoprtion overtime
incrseased cost as need relines and rebases
Review appts after imeedaite denture placement
24hrs - to check socket area and healing
1 week - to check the denture and healing status
1month - the socket will have healed check denture retention
3-6months potential for reline/rebase of denture
12 months - provide new denture for pt using the copy technique
Reline
the addtion of a lining materia on the fitting surface of thre denture to fil the space between the denture and the new contoured tissue
Rebase
the complete removal of the denture base and replaced with a new one
uses for reline and rebases
only if the only issue is do with retetnion
pt happy to live without denture for period of time
reline advantages
can be carried out at chairside
improves retetnion
can be permanent or temporary
Rebases advatanges
does not alter the paaltal thickeness
allows the colour of denture bases to change if been bleached
types of relines
temp - implant surgery, tissue conditioner
soft - used for cancer pts, bruxists, atrophic ridges
permanenent - acrylic - for immediate dentures, bad master imps, perpiheral seal
replica dentures
replicated polished surface of the denture and can have some small changes e.g - occlulsion and adaptation
why do copy dentures
if pt wants a second set - care home
detoritation of the denture base
immediate dentures requires
retention is the only issue with the denture
good occlusion and polished surface
wear of occulsa surface
contra indications for copy dentures
if there are more issues than just renttion - ovd, neutral zone, facial height
pt has lost denture
issue with polished surface of dentures
Loose denture
polished surface - over or under extended
occulsal surface - high occulsal plane, new jaw reg required
impression surface - lack of adhesvice, mandibular atrophic rdige, flabby rdie, bony deposits, warping denture base
neatural zone
the teeth on the denture base are plasced in an area to ensure maximum avoidance of muscles extra and intra orally
complaints of dentures
ulcers
dry mouth
angular chelitis
denture stomatitis
denture induced hyperlpasia
speech and speaking diificults
pain on cheek and tongue
pain on one side
teeth meet too soon
localised pain to premolar region
lack of chewing, collapse in face
poor mastication
flappy ridge
where bone resoprtion and loss has occrued and replaced with fbirous tissue
support weak and leads to insibility
netural zone
the teeth ares et on the denture base to ensure maximum reduced interfence with the exntra and oral muscles
the tongue and the lips and cheeks are at equilibrium with oe another
over dentures
gains support by covering one or more teeth, the roots of teeth been treated or implans
indcations for over dentures
pt transitioning from partial to complete dentures
elederly pts with few remaiining teeth and mucosal born denture support
attrtion/erosion/abrasion
hypodontia
cleft palatle
not to sue overdentures when
poor oh
caries risk high
erio status poor
retention
rethe resitance to vertical movment of the dentures away from the tissues
what provides retetnion
muscular - the lips, tongue, cheeks, mom
physical - adhesion/cohesion with salvia between denture and mucosa, surface thension, viscotiy
how to acheive retetnion
large impression surface
accruace of fit - thin acrylic on fitting surface
denture fixatives
sft linings
post dam placmeent
extended flanges and good border seal
Support
the resitance of the denture to occulsal y directed loards towards th etissues
acheived by soft tisses and the alvolar ridge
manidble - buucal shelf, retromolar pads, alveolar mucosa
maxialla - hard paalte, alevolar mucosa, zygomatic butress, resudal shelf
Stability
resitance of denture to horizontal and rotational forces
use a light denture to help with gravity
ensure netural zone manintaed
good occulusion
upper muscles - buccinator, oris, levator anguli
lower muscles - buccinator, superior constrictor, depressor labii iferorisis
crietiera for a denture base
dimensianally stable
radiopaque
non irritant
non toxic
insoluble
inexpensive
long shlef light
high softening temp
good asethetics
insoluble in water
high elastic limit
high thermal conductivity
high abrasion resisitance
high impact strength
PMMA
advatanges - high softening temp, dimesinally stable. good aethetics
disadvatnages - radiolucent, low theraml conductivity
PMMA issues
poroosity - gaseous due to monomer boiling away, contraction insuffiecnt pressure
granuiliaty - insufficent mixing ratio
crazing - due to the differnce in coeffeicnts between the acrylic base and porcelain teeeth
residual monomer - can casue irritation
Mandible
suppport - buccal shelf, alevolar residular ridge
limign - buccal and lingual sulcus and frenum, retromolar pads
relief - genia ltubercles, tori, mylohyoid rdige
Maxialla
support - ruguae, hard palate
relief - plataine fovea, incisal papille, palatine fovea
liminting - buccal and lingual frenum and sulucus, hamular notch
Static occlusion
contact ebtween the teeth when the madnible is not moving
Dynamic occlusion
contacts made betweenthe teeth when the mandible s moving
ICP
occlusion the person makes with theri teeth when they bite down in mainmum intercuspation - centric occlsuion
Kennedy classes
class 1 - unilateral free end
class II - biltaeral feee end
class III - bilateral bounded
class IV - anterior bonunded
craddock classes
claa 1 - tooth borne
class ii - mucosa borne
class III - tooth and mucosa borne
Aims of dental surverying
to determine the path of insertion
to determine the presence of guide planes
to provide survery lines to check for preence of undercuts adn depth/position
Guide planes
an extra area of retention close to the base and parallel to the path of insertion
Clasps
0.155mm ot engage a 0.25mm undercut
undercut guages
0.25mm - cocr
0.5mm - gold
0.75mm - wrought S.S
Reciprocation
an opposing element to the clasp arm which prvents too much pressure of the classp on the tooth
Guide planes provine
incrases stability and appearance
reciprocation
prevent of clasp deformation
Aims of rests
to prevent overuption of unopposed teeth
to allow even distrubution of occlulsal forces
indirect retention
reciprocation
to determine the axis of rotation in free end saddles
prevent movment of RPD towards mucosa
issues with rest seats
can remove tooth tissue
can expose dentine
loss of occlusal stops when denture not worn
Path of displacement
direction in which the denture dislodges during function and perpendicular to occlusal placne
RPI
r = mesial rest
p- distal proximal guiding plate
I = i bar clasp
the denture saddle compresses on the oral mucosa and rotates around the mesial rest. the distal plate and the i bar move down and disengage from the tooth to avoid torque
it relieves stressts on the abutment tooth cclose to the free end saddle
