Dentures Flashcards

1
Q

Neurocentric

A

Position: closest to the tongue as possible
Proportion: reduce Occlusal table by 40%
Pitch: parallel between ridges
Form: non-anatomic
Number: reduce posterior teeth from 8 to 6

Devan

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2
Q

Neil’s Lateral Throat form

A

Class I: 8-12mm of extension below the mylohyoid ridge (long, wide flange)
Class II: 4-6mm of extension below the mylohyoid ridge
Class III: 2-3mm of extension below the mylohyoid ridge; RARE

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3
Q

Kelly Combination syndrome

A

Papillary Hyperplasia
Max ant ridge resorption
Extrusion of mand ant teeth
Downgrowth of tuburosities
Resorption of mand post ridge

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4
Q

House palatal throat form

A

Class I: 5-12 mm post from hard palate
Class II: 3-5 mm post to hard palate
Class III: anterior to hard palate

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5
Q

The area in the mouth where the force of the tongue pushing out is neutralized by the forces of the cheeks and lips pressing inward so that normal muscle activity retains dentures rather than dislodges them.

A

Neutral Zone

Berersin Scheiser

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6
Q

Dentogentics

A

Frush and Fisher

Sex
Age
Personality

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7
Q

Balancing ramps

A

Nepola and Sears

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8
Q

PDI for edentulism

A

1) residual bone height
2) residual bone morphology
3) muscle attachments
4) maxillo-mandibular relationship

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9
Q

Pear shaped pad

A

Cradock

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10
Q

-6 factors of retention

A

adhesion: the physical attraction of unlike molecules
​-cohesion: the physical attraction between like molecules
​-interfacial surface tension: resistance to separation by the film of liquid between
the denture base and the supporting tissues (combines cohesion and adhesion).
​-mechanical locking into undercuts
​-peripheral seal and atmospheric pressure: *the most important factor
​-orofacial musculature: correct position of denture teeth must be in the neutral zone

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11
Q

The quality of a prosthesis to resist displacement by functional horizontal or rotational stress. THIS IS THE MOST IMPT FACTOR. Occlusion that is not balanced in excursive movements will create instability of the denture, loss of retention and eventually frustration to the patient.

A

Stability

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12
Q

The quality inherent in the prosthesis that resists dislodgement along the path of insertion

A

Retention

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13
Q

6 purposes of posterior palatal seal

A

​1. retention of max denture
​2. firm contact with the palatal tissue reduces the gag reflex
3. it reduces food accumulation
​4. the pressure on the tissue makes the distal border of the denture less noticeable to the dorsum of the tongue.
​5. it compensates for dimensional change
6. the thickened area provides added strength across the denture

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14
Q

the arbitrary terminal hinge axis: measured out from the posterior margin of the tragus of the ear – 13mm on a line between the tragus of the ear and the outer canthus of the eye.

A

Beyrons point

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15
Q

Hanau’s formula

A

L = H/8 + 12
​-H is the horizontal condylar inclination established by the protrusive record
​-L is the lateral condylar inclination

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16
Q

Theilman’s formula

A

K(balance) = IG x CG / CH x OP x CC

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17
Q

Foundation area on which a dental prosthesis rests

A

Denture support

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18
Q

5 ways to improve denture support

A

​1. surgical removal of pendulous tissue
​2. use of tissue conditioning materials
​3. surgical reduction of sharp/bony ridges
4. surgical enlargement of ridge
5. implants

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19
Q

6 advantages of a anatomic teeth

A

​-1. Can establish mechanical and physiologic occlusion.
​-2. Penetrates food more easily.
​-3. Articulate in harmony with TMJ and masticatory muscles.
​-4. Resists rotation of denture base through interdigitation with cusps.
​-5. Better esthetics.
​-6. Less trauma to underlying tissues.

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20
Q

What is Frenum composed of?

A

Non keratinized, unattached alveolar mucosa with an underlying fibrous attachment to bone. 35% of max frenum have small striated muscle; Gartner, 1991

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21
Q

Muscles of Mastication

A

●Temporalis
Origin: lateral surface of the skull (temporal fossa)
Insertion: Coronoid process, anterior border of ramus
Action: elevates mandible, posterior part retrudes jaw
●Masseter
Origin: zygomatic arch (process)
Insertion: lateral surface of ramus, coronoid process
Action: elevates mandible
●Medial Pterygoid
Origin: medial surface of lat pterygoid plate, pyramidal process of palatine and tuberosity
Insertion: medial surface of ramus
Action: elevated mandible
●Lateral Pterygoid:
Origin: lateral surface of lateral pterygoid plate
Insertion: neck of condyle and Disc and capsule of TMJ
Action: depresses, protrudes, moves mandible side to side

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22
Q

What is in retromolar pad?

A

•glandular tissue
•loose areolar tissue
•pterygomandibular raphe
Superior pharyngeal constrictor
Buccinator
•Tendon of the Temporalis
•Most impt: cortical bone underlying these structures

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23
Q

How long leave denture out?

A

48-72 hours

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24
Q

How to balance monoplane setup

A

Balancing ramp

Nepola and Sears

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25
PDI Classification for edentulism
1) residual bone height 2) residual none morphology 3) muscle attachments 4) maxillo-mandibular relationship
26
How to mark PPS
Empirical method; visually marked the vibrating line (ah technique) with Thompson indicator stick which transfer mark to record base. Adjusted the record base to this line and transferred to master cast
27
Landmarks for setting teeth and occusal plane
Esthetics; parallel to the inter-pupilary line and ala tragus line Neutral zone impression: Fish; Beresin, Scheiser; ant corresponds to the modiolus Mandibular first molar is 2/3 way up the retro-molar pad
28
What are some reasons for porosity in processing?
If rate of reaction is too high you will get porosity; heat slow
29
What is Passavants pad
A prominence on the posterior wall of the naso-pharynx formed by contraction of the superior constrictor of the pharynx during swallowing.
30
Wax Classification
Baseplate: Type I, soft; Type II, medium; Type III hard (75% Parafin) Casting: Type I direct(medium hard), Type II indirect(soft) Modeling plastic: Type I stick, Type II cake
31
What is compound wax
“modeling plastic” Low thermal conductivity: it requires time for cooling to prevent distortion ADA Spec #3: Type I, stick; Type II, cake
32
Compound specifications
Flow at 98.6 F is >6% Thermal Contraction is .3% Softening temperature: Green, 123F Red, 132F
33
Green stick compound makeup
Rosin Copal resin Carnauba(filler) Talc Rouge(color) Stearic Acid(fat
34
Ways to evaluation vertical dimension
Physiologic rest Phonetics Pre-treatment records Closing forces Ceph Esthetics Tactile Swallowing Wear
35
Closest speaking space clearance
Class I: 2-3mm Class II: 3-6mm Class III: 1mm
36
Frankfort horizontal plane
Lowest point on orbit to Highest point on external auditory meatus Porion to orbitale
37
Why use blue mousse
Initially dead soft Fast set Sets rigid Dimensionally stable Unaffected y disinfectants Can be trimmed
38
What are the four methods of obtaining CR
1) Static Recordings; Direct interocclusal records 2) Graphic recordings; started with Balkwill but Gysi first to record mandibular movement and CR, pantograph, coble balancer (Hardy and Pleasure) 3) Functional Records: myomonitor, swallowing with compound cones, stereograph (TMJ- articulator- Swanson and Swif); chew-in Myers 4) Cephlometrics- Atwood
39
What are 4 ways of guiding patient?
1) swallowing (.4mm error); Shannahan (static) 2) chin point guidance (.14 error); Gnathology (static) 3) chin point w/ ant jig (.07 error); Lucia (static) 4) bimanual manipulation (.05 error); Dawson (static
40
Define CR
A maxillomandibualr relationship in which the condyles articulate with the thinnest avascualr portion of the disc with the complex in an anterior superior relationship against the articular eminance
41
What bacteria are in caries
Strep mutans (8 serotypes): found in everyone; probably responsible for onset Lactobacilli: probably responsible for progression of cavitated lesions Strep has ability to adhere to tooth structure, and form sticky matrix
42
Fluoride level
Optimal in water 1ppm >10 cause fluorosis
43
Saliva quantity
1000-1500 ml/day Parotid - 26% - serous Submandibular - 69%- mixed Sublingual & palatine - 5% - mucous
44
Facial forms for denture teeth
Williams classification Square Tapering Ovoid
45
Dentogenics
Frush & Fisher Sex Personality Age
46
Muscles of masseteric notch
Buccinator and masseter
47
How to treat Candida Albicans
Nystatin rinse 5ml qid 10 days Ketoconazole 200-400mg daily 1-4 weeks
48
Treatment for patients with xerostomia
Sialogogue therapy Pilocaprine 5mg qid
49
Acrylic powder
Polymer-PMMA Initiator - benzoyl Peroxide (decomposes after 60 degrees Celsius) Pigments - mercuric sulfide, ferric oxide, carbon black Dyes - leach out by oral fluids Opacifiers - zinc or titanium oxide Plasticizers - dibutyl phthalate
50
Acrylic liquid
Monomer - MMA Inhibitor - hydroquinone; prevents premature polymerization Accelerator - tertiary amine; dimethyl-para-toludine; used in auto polymerization to initiate peroxide decomposition Plasticizer - dibutyl phthalate- creates plasticity Cross linking - glycol dimethacylate - resists cracking and crazing
51
Steps of acrylic
Initiation: formation of free radicals; heat/amine +peroxide = free radicals Propagation: free radical + monomer = growing polymer chain Termination: hydroquinone + free radical = polymer chain
52
What is triad
Urethane dimethacrylate initiated by light (400-500 nm) and camphoriquinone 3% shrinkage
53
What are high impact resins reinforced with?
Butadiene styrene rubber
54
Initial PMMA shrinkage
Volumetric 21% Linear 7%
55
Pre-polymerized shrinkage
Volumetric 6% Linear .5%
56
Types of Shrinkage
1) thermal- due to different CTE of stone and resin 2) polymerization Shrinkage- due to covalent bonds which occupy less vol than unbound mole.
57
Dentate vs. edentulous bite force
Dentate 200psi Edentulous 50psi
58
Earl Pound concept for maxillary central incisor
The central incisor length = the face length / 16
59
the angle formed between the saggital plane and the average path of the advancing non-working side as viewed in the horizontal plane during lateral mandibular movements.
Bennett Angle
60
Fisher’s angle
The angle formed by the intersection of the protrusive and non-working side condylar paths as viewed in the saggital plane when recording of mandibular movement is made by using a device located lateral to the TMJ.
61
a plane that passes through the inferior border of the mandible.
Mandiblar plane
62
The space that occurs between opposing posterior teeth during mandibular protrusion.
Christensen phenomenon
63
Decrease percent of complete edentulism by 2050
2.6% Decrease in edentulism but increase in population
64
3 Indications for pre-prosthetic tori removal
A torus that extends beyond the posterior palatal seal area A torus with overlying traumatized tissue/mucosa A torus that interferes with function (speech and deglutition) Contra-indication- tori fills more than half the palate
65
Advatanges of lingualized occlusion
Reduces lateral forces on the denture bearing tissues Vertical forces are centered upon the mandibular residual ridges This scheme yields cross-arch, but not cross-tooth, balance
66
During protrusion of the mandible, what are the actions of the superior and inferior heads of the lateral pterygoid muscles?
Superior head relaxes Inferior head contracts
67
What is the primary function of the superior head of the lateral pterygoid muscle?
Positioning the articular disk during closure.
68
Types of Osteoporosis
Type I: primary—makes up the vast majority of cases—post-menoposal –loss of estrogen resulting in increased bone turnover, with predominant loss of travecular bone Type II secondary—senile osteoporosis—gradual age-related bone loss found in both sexes caused by systemic senescense—induced by loss of stem-cell precursors, with predominant loss of cortical bone Type III Osteogenesis Imperfecta—due to genetic mutation, affecting 6/100,000 people (eight known types of OI) Type IV Idiopathic juvenile osteoporosis—no known cause, and usually has onset just before puberty
69
What are the types of oropharyngeal candidiasis
Acute pseudomembranous candidiasis Acute atrophic candidiasis Chronic atrophic candidiasis Chronic hyperplastic candidiasis Angular chelitis Median rhomboid glossitis
70
Sleep hypopnea index
STOP BANG Mild: 5-15 events/hour Moderate: 15-30 events per hour Severe: > 30 events/hour Tongue size Male Neck circumference
71
Tallgren average bone loss over 25 years
Maxilla .05 per year Mandible .2 per year
72
Average thickness of periosteum
.375mm
73
TNM classification
T=primary tumor size N=node size M=presence of metastatic sites
74
What does face bow record?
records the spatial relationship of the maxillary arch to the hinge axis
75
What etiologic factors are associated with denture stomatitis
Poor denture hygiene Continual and nighttime wearing of dentures Accumulation of denture microbiota Ill-fitting dentures
76
Which oral microbes are responsible for denture stomatitis
Candida albicans Candida tropicalis Candida glabrata Candida pseudotropicalis Candida guillierimondii Candida krusei
77
What are the effective doses of radiation for the following dental radiograph
Cephalogram = 10 uSv Panoramic = 14.2-24.3 uSv Full-mouth series = 13 – 100 uSv CBCT = 19-1073 uSv (depends on machine)
78
The triangle formed by lines drawn between the mandibular incisors and right and left condyles
Bonwill triangle 4 inches
79
The angle formed by the imaginary plane of the Bonwill triangle and the mandibular occlusal plane (described by the incisors and disto-buccal cusps of the mand 2nd molars).
Balkwil angle
80
Composition of dental plaque
70% bacteria 30% intracellular matrix consisting of carbohydrates, proteins, calcium ions, and phosphate ions
81
Landmarks for Campers plane
Inferior border of the right or left ala of the nose and the superior border of the tragus of the ears.
82
Objectives of complete denture final impression
Preservation of hard and soft tissues—pressure in the impression technique is reflected in the denture base and can result in soft tissue damage and bone resorption Support--maximum coverage of the appropriate denture bearing areas—the “snowshoe” effect Stability—close adaptation to the underlying mucosa is important in reducing horizontal movement of the dentures Esthetics—border thickness should be varied to restore facial contour and proper lip support Retention—atmospheric pressure, adhesion, cohesion (depends on peripheral seal), mechanical engagement of undercuts, muscle control
83
Denture impression philosophies
Muco-compressive Muco-static Selective pressure Functional
84
Thermoplastic modeling compound heat temp
Red 132-133 Gray 128-130 Green 122-124
85
the composition of Dentsply IPN 3D denture teeth?
Urethane methacrylate 3,3,5, trimethyl cyclohexanol-Alkyl methacrylate Ethylene Glycol Alkyl di-methacrylate Phosphorolated bisphenol A urethane di-methacrylate oligomer Diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide Carbon black Titanium Dioxide Butylated hydroxytoluene
86
physical and mechanical properties of Dentsply IPN 3D denture teeth?
Wear resistance (Volume loss): 0.09 mg/400,000 cycles (ISO = > 65 MPa) Flexural strength (130 MPa). (ISO = > 2000 MPa) Compressive strength = 145 MPa (ISO = > 110 MPa) Hardness: 0.41 GPa Elastic modulus: 5.51 GPa
87
classification of denture base materials?
a. Type 1—heat curing polymers—polymerization temp >60o C b. Type 2—self curing polymers—polymerization temp <60o C c. Type 3—thermoplastic materials—polymers moldable when heated d. Type 4—light cured materials—cured by UV or visible light e. Type 5—microwave materials—heat cured polymers cured with microwaves
88
What is Ivobase
Combines benefits of heat cured and self-cured polymers. Requires polymerization temp of only 40o C.
89
Benefits of Ivobase
a. Thermal loss much lower b. Increases in VDO are virtually eliminated—little to no post-processing polymerization adjustments required c. Fracture toughness equivalent to heat-cured polymers d. Low residual monomer content e. Overall curing time is 35 min (Ivobase hybrid), 50 minutes for IvoBase hi impact) f. Cooling time is 15 minutes
90
What are the stages of polymerization following correct mixing of PMMA materials?
a. Sandy—little polymerization, grainy in appearance b. Stringy-monomer molecules attack and dissolve PMMA particles, and disperse polymer changes in the liquid phase; larger PMMA particles unfold and enhance viscosity. Stage is characterized by sticky strings upon touching or stretching. c. Doughy: characterized by lack of stringiness and stickiness—this is the suitable stage for packing into a flask. d. Rubbery stage—further conversion of monomers into polymers, and evaporation of residual monomer. Rubbery appearance of the matrix (rebounds after releasing from compressive or tensile stresses) e. Stiff stage: continued polymerization and evaporation—results in hardening and reinforcement of mechanical properties. PMMA becomes dry, stiff, and resistant to plastic deformation.
91
What is the significance of residual monomer content?
May have a sensitizing effect on patients.
92
What types of fibers may be used to enhance the PMMA base materials physical properties?
a. Carbon b. Kevlar (aramid) c. Nylon d. Polyethelene and polypropylene e. Glass
93
What are prosthetic denture teeth made of?
PMMA, composite resin, or porcelain
94
Muscles of soft palate
Palatoglossus Palatopharyngeus Tensor veil palatini Lavator veil palatini Musculus uvulae
95
Contents of retromolar pad
Glandular tissue Loose areolar tissue Tendon of temporalis Pterygomandibular raphe Underlying cortical bone
96
Contents of retromylohyoid fossa
Medial - mylohyoid Posteromedial- palatoglossus Posterolateral -superior constrictor Distal - styloglossus
97
Floor of the mouth
Mylohyoid Genioglossus Geniohyoid
98
7 Muscles of modiolous
Buccinator Obicularis oris Risorius Zygomaticus major Zygomaticus minor Levator anguli oris Depressor anguli oris
99
Saliva composition
Ptyalin(salivary amylase)-serous Mucins-mucous Bactericidal: Thiocyanate ions, proteolytic enzymes, protein antibodies
100
Wolfs law
A bone will develop the structure most suited to resist the forces acting on it
101
Mucosa in mouth
Superior to inferior: Mucous membrane-mucosa-submucosa(vessels and nerves)-periosteum-bone Masticatory Mucosa-submucosa has base of fibrous CT and covering of keratinized CT Gingiva and palatine raphe have no submucosa Lining Mucosa-nonkeratinized Specialized Mucosa-dorsum of tongue, has taste buds
102
What’s in hamular notch
Junction of maxillary tuberosity and hamular processes of medial pterygoid plate Origin of pterygomandibular raphe Tendon of tensor veil palatini
103
Innervation of tongue
Anterior 2/3: lingual nerve Posterior 1/3: glossopharyngeal Taste: chorda tympani (branch of facial) Motor: hypoglossal Protrudes tongue: genioglossus Blood supply: lingual artery
104
Ligaments that attach to mandible
Collateral Origin: Medial and lateral poles of disc Insertion: Medial and lateral poles of condyles Function: Restrict movement of disc away from condyle Capsular Origin: superiorly to temporal bone Insertion: inferiorly to neck of condyle Function: resists medial, lateral, inferior forces that tend to dislocate articular surfaces It encompasses entire TMJ, is well innervated and gives proprioceptive feedback Temporomandibular Outer oblique portion Origin: articular tubercle(outer surface) and zygomatic process Insertion: Condylar neck(outer surface) Function: Permits rotation but limits it also (not >15mm) Inner Horizontal portion Origin: articular tubercle (outer surface) and zygomatic process Insertion: lateral pole of condyle and posterior part of articular disc Function: limits posterior movement, provides bracing for lateral and retruding movements Sphenomandibular ligament Origin: spine of the sphenoid bone Insertion: lingual Function: no limiting effects on mandibular movement Stylomandibular ligament Origin: styloid process Insertion: angle and posterior border of mandible Function: Limits excess protrusion of the mandible
105
Action of levator veli palatini
elevates soft palate, brings lat pharyngeal wall medially
106
Action of uvulus
Thickens and lengthens soft palate
107
Action of superior constrictor
Brings post pharyngeal wall anteriorly
108
has intact structures but has inability to perform closure (neurological)
palatal pharyngeal incompetency
109
Palate does not have intact structures
palatal pharyngeal insufficiency
110
Innervation of speech
V: muscles of soft palate (trigeminal) VII:muscles of periphery of mouth (facial) IX: pharyngeal muscles (glossopharyngeal) X: pharyngeal muscles, laryngeal muscles, soft palate (vagus)
111
What is the physiology of speaking?(Martone)
Three Physiologic Valves •True vocal folds of the larynx •Palatalpharyngeal region: nasal, oral and laryngeal pharynx •Mouth
112
What is the physiology of gagging?
Afferent to medulla oblongata: V, IX, X; general innervates fauces, base of tongue, palate, uvula, and posterior pharyngeal wall(common trigger points) Efferent: V,VII,X,XII, pharyngeal plexus(IX,X,XI), various sympathetic and parasympathetic nerves
113
Causes of gagging
Systemic, Psychological, Physiological, Iatrogenic(overextended, too thick, highly polished, inadequate postdam)
114
Reason to use fully adjustable articulator
Anterior/posterior control Centric stop Anatomical accuracy
115
Celenza classification
Class I: simple holding Class II: vertical and horizontal movement, but not related to TMJ A: motion unrelated to pt B: motion based on theories C: motion based on patient Class III: condylar pathways using average anatomic values A: static protrusive records B: accepts lateral records Class IV: 3-D registrations A: paths formed by patient (TMJ) B: paths from settings and inserts (D5A)
116
Who developed first facebow
Snow
117
Arcon vs. non arcon
Arcon is where is condylar elements are on the lower member and semi adjustable has condylar pathways based on scientific averages Non arcon condylar element is on the upper member, you can get a 8 degree difference in the arc of closure if you increase the pin opening or from you CR records
118
What is average intercondylar distance
110mm
119
Mandibular movement averages Horizontal Condy Inclination IMLT Progressive Curve of eminentia Intercondyler distance Bennett
Horizontal Condy Inclination 37 degrees IMLT .75mm Progressive 7.5mm Curve of eminentia 3/4 inches Intercondyler distance 110mm Bennett 16 degrees
120
Hanau Quint
Condylar Inclination Incisal Guidance Compensating Curve Cusp Height Plane of Occlusion
121
Jaw movement measurements Hinge Max opening Excursive
Hinge: 20mm Max opening: 40-60mm Excursive: 8-10mm
122
Bodily shift in the mandible in the direction of the working side
Laterotrusion
123
Long centric
The anterior teeth should immediately disclude the posterior teeth but at a controlled angulation so that you don’t lock the patient in. The patient must have an unimpeded path to centric relation. PMS
124
Detrusion, surtrusion, retrusion definitions
Laterodetrusion: lat and down on working side Laterosurtrusion: lat and up on working side; greatest effect since it brings arches closer together Lateroretrusion: lat and back on working side
125
What systemic conditions affect the basal seat/denture prognosis
Osteoporosis Xerostomia Mucosal disorders Burning tongue Dermatalogic disorders Radiation Therapy Chemotherapy
126
Soft liner vs. tissue conditioner
Tissue conditioner- less viscous – more flow, change and adaptation to the tissues, flow easily and have a low viscosity; Coe-soft. Soft liners – more viscous; Coe comfort
127
What are soft liners made of?
Soft Liners are plasticized acrylic resins, either PMMA or PEMA and the liquid plasticizer dibutly- phthalate. The large plasticizer minimizes entanglement of polymer chains, thereby permitting chains to slip past each other to allow a rubbery-like state. The liquids do not contain acrylic monomers only to be used short term. Plasticizers leach out over time and the material becomes more rigid. Biggest issue is the inability to thoroughly clean the surfaces, hence candida albicans is a major issue.
128
What is the REALEF Effect?
The resilience and like effect was described by Hanau and is used to describe the fact that the soft tissue under the denture base has movement so it compensates for any limitations of the articulator.
129
Discuss mucostatic impression?
Henry Page; soft tissue should be in unstrained postion for impressions; relies on interfacial surface tension for retention; disregards cohesion (like) and adhesion (unlike) Resulting denture is almost flangeless and will not be very retentive
130
Discuss selective pressure technique?
Peripheral tissue s are slightly displaced to increase retention You displace the tissues just enough to get retention but not to loose stability This method uses adhesion, cohesion and surface tension
131
Border molding maxilla
Anterior: lip is elevated and extended outward, downward, and inwar.(orbicularis oris fibers run horizontal –only indirect effect); no muscles in labial vestibule Buccal Frenum: Cheek is elevated and pulled outward, downward and inward; also it is moved forward and backward to simulate movement of both the orbicularis oris and the buccinators; the levator anguli oris is under the buccal frenum Posterolateral: rub with hand, open wide, move jaw side to side; pterygomandibular raphe (buccinators/sup constrictor) and coronoid process, and also medial pterygoid when patient open up wide
132
Border molding mandible
Labial flange: lift the lower lip outward, upward and inward ; mentalis and orbicularis oris Buccal Frenum: Cheek is lifted outward, upward, and inward, backward and forward to simulate frenum movement; depressor anguli oris is under buccal frenum Posteriorly: cheek is pulled buccally to ensure that tissue is not trapped, then the cheek is moved upward and inward. Anterior Lingual Flange length(PM TO PM): Ask patient to protrude the tongue activates the genioglossus, raises sublingual fold Anterior lingual flange thickness: push the tongue against the front part of the palate Posterior edge of posterior lingual flanges: when tongue is pushed against the front part of palate it activates mylohyoid AND the superior constrictor which supports the retromylohyoid curtain) Inferior edge of both posterior lingual flanges: are border molded by touching tongue out and then into the opposite cheek; floor of retromyhoid region is the palatoglossus Distal of retromolar pad and masseteric notch: Open wide caused pterygomandibular raphe to be brought forward, thrust tongue out and then close the mouth. The downward pressure on the mandible activates the elevators of the mandible thus the masseter pushes on the buccinator marking the masseteric groove and medial pterygoids push against the retromylohyoid curtains distal end of the lingual flange.
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Stress bearing areas maxilla
Primary stress bearing areas: hard palate lateral to median raphe In some patients the maxillary ridge crest is considered a primary stress bearing area and in other patients it is considered a secondary stress bearing area (Jacobsen & Krol)
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Stress bearing areas mandible
Primary stress bearing areas: buccal shelf and pear shaped pad Secondary stress bearing areas: residual ridges
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House Personality classification
Hysterical-most difficult, poor prognosis Indifferent Philosophical Exacting
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Cross tooth cross arch advantages
Zarb - Boucher text -Better aesthetics -Ease of penetration of food -Stablility during swallowing and parafunctional movements Introduced by Gysi 1927
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Occlusal spectrum
Parr and Loft 1982 Anatomic Semi Anatomic Lingualized NonAnatomic Neutrocentric – NonBalanced (DeVann)
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What factors affect denture Stability? (Jacobsen and Krol)
Tissue surfaces (lingual flange, residual ridges shape and contour) ●Polished surfaces (muscles must not be interfered with by denture base and the muscles may help seat and stablilize denture base. Note: Fish though that polished surfaces were the most impt factor in stability ●Occlusal surfaces: Free of interferences
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What factors affect denture Support?(Jacobsen and Krol)
Extension to maximum surface area and border extensions. Note: Tissues that resist resorption and vertical displacement have more pressure under function.
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Maxilla shapes
Flat, round, u shaped, v shaped
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Wright classification tongue position
Class 1 normal Class 2 normal but broad and flat Class 3 retruded
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House tongue size classification
Class 1 normal Class 2 teeth absent long enough for tongue to flatten Class 3 excessively large
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Why choose Stratos 300?
Fulfills Celenza class IIIB semi adjustable Control of horizontal condylar inclination and Bennett angle
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6 Advantages of Stratos 300
Wide posterior view Centric latch to only allow hinge movement in CR Curved condylar path (12.5) Ability to incorporate protrusive and lateral check bite records Incisal table with a fixed pin Arcon articulator with condylar element on lower member following pt arc of closure
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Adjustable elements of Stratos 300
Bennett angle 0-30 IMLT 0-1.5mm Protrusive advance 0-4mm Retrusive advance 0-2mm
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Stratos based on 4 main geometric conditions
Campers plane Balkwil, angle Bonwill triangle Monsoon template
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How did you program articulator for HCI and laterotrusion
HCI - protrusive check bite Laterotrusion - Hanau formula or lateral check bite
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Process denture base materials
Ivobase Ivocap Press pack (lucitone 199)
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3 ways to determine PPS
Functional - Iowa wax Semi functional - border model Arbitrary- 1-2,m beyond vibrating line
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Shapes of PPS
Butterfly Bead Butterfly with roll Double bead
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Denture adhesive categories
Adhesives - methyl-cellulose Anti-microbial agents - sodium tetraborate Others - wetting agents
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Specs for microstone
ISO Type 3 Brand:Premium dental stone 40ml/140g water to powder 5-7min working time 15 min set time 0.12% expansion Compressive strength (MPA) after 1 hr 31 after 48 hr 59
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Specs for mounting plaster
ISO type 1 Brand: “low expansion fast setting plaster” 63ml/100g water powder 60-90s working time 3 mins setting time .09% expansion Compressive strength (MPA) 1 hr 4 after 48 hrs 12
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What does UTS stand for
Universal transferbow system
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Anatomic structures for s curve
Mylohyoid, palatoglossus, superior constrictor
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What impression philosophy did you use and why
Selective pressure- putting selective pressure on primary denture bearing areas
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Why do teeth stay balanced in mouth
Realeff and denture movement
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What limitations to my articulator
Cannot adjust intercondylar distance
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What error comes from arbitrary facebow
Not accurately find hinge access .2mm error - Weinberg
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Gypsum formula
Ca sulfate hemihydrate + water = calcium sulfate dehydrate + heat
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The process of heating gypsum to drive off part of crystallization to form hemihydrate
Calcination
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Gypsum classifications
Type I Impression Plaster - 15% exp Type II Model Plaster - .30% exp Type III Dental Stone - .20% exp Type IV Improved stone - .10 exp Type V High Strength, Exp - .30 exp
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Alginate composition
Potassium alginate Calcium sulfate dehydrate K Phosphate Na Phosphate Diatemaceous Earth Glycols
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PVS composition
Base: dimethyl siloxane with silane groups Fillers such as copper carbonate which control consistency Accelerator: vinyl terminated siloxane Chloroplatinic acid