thickness of minor RPD connectors
1.5 mm
Minimum space between vertical components of RPD
5 mm
Kennedy Class I
bilateral distal
... [Show More] extension
Kennedy Class II
unilateral distal extension
Kennedy Class III
entirely tooth born with teeth anterior and posterior
Kennedy Class IV
edentulous area anterior to remaining teeth
Lingual bar distance from gingival margin
3 mm
Lingual bar width (minimum)
4 mm
Maxillary major connectors, how far from gingival margin
6 mm
Max RPD bead line width and depth
.75-1 mm
Anterior-posterior palatal strap, minimum distance between straps and minimum width for each strap
15 mm between, 6 mm anterior and 8 mm posterior
Palatal plate advised when?
The last abutment on either side is a canine or premolar
Main function of indirect retainers
prevents vertical dislodgement of the distal extension base away from tissues (sticky food)
Minimum number of rests for RPD
3
For a distal extension where is the rest on the most posterior tooth
mesial
rest seat depth
1.5 mm at marginal ridge and 2 mm in center, at least 2.5 mm wide
what is prepared first? Guide planes or seats
guide planes
extended occlusal rests used when?
used when most posterior molar abutment is mesially tipped in class II (mod I) and class III
Cingulum rest depths
2 mm wide (F-L), 2.5-3 mm (M-D), 1.5 mm deep
Guide plane position relative to height of contour for classes of RPD
Class III and IV can end above the height of contour because there is no functional movement. Class I and II must be below the height of contour (to prevent torquing). With I-bars and mesial rests on premolars, must end exactly at the height of contour.
how to determine number of clasps
kennedy classification + 1 (except for class IV)
Undercut of 0.01
cast clasp
Undercut of 0.02
wrought wire (0.5 mm and must be at least 8 mm long, 18 gauge)
chromium provides what
corrosion resistance
cobalt provides what
rigidity
Nickel provides what
ductility
What muscle dictates the DB of the mand flange of a denture
masseter
What muscle dictates the DL of the mand flange of a denture
superior constrictor muscle
how far to trim back the custom tray from the mucosal reflection
2 mm
occlusion rim heights
maxillary 22 mm, mandibular 18 mm
The inferior surface of the maxillary occlusal rim should be parallel to...
Camper's Line (Ala-tragus Line) and inter-pupillary line
primary and secondary support for mand denture
primary - buccal shelf, secondary - alveolar ridge
Posterior palatal seal
extends through the hamular notches, 2 mm in front of fovea palatinae, carried 5 mm anterior to the vibrating line
if denture falls down when smiling
buccal notch and buccal flange are excessively thick
Golden Proportion Ratio
1.6:1:0.6 (central:lateral:canine)
S sounds like "th"
either max anteriors are too far palatal or palate is too thick. S sounds bring the max and mand closest together (than other sounds)
Occlusal clearance gold
1.5 mm functional, 1 mm non-functional
Occlusal clearance PFM
1.5-2 mm functional, 1-1.5 non-functional
all ceramic clearance
2 mm
Percentages for PFM copings
high noble (98% gold, platinum and palladium - these metals do not oxidize on casting), Noble (50-60% palladium, 30-40% silver - silver will oxidize), Base (70-80% nickle, 15% chromium - these both oxidize on casting)
Coping thickness
noble metal is 0.3-0.5, base as thin as 0.2
Implant overdenture minimum space
locator - 8.5 mm, ball and o-ring - 10-12 mm, bar clip - 13-14 mm
Polysulfide impression material
rubber base, setting time of 12-14 min
PVS
poured up to 1 week, hydrophobic, do not wear latex gloves, 6-8 min setting time, temperature sensitive (sets faster in heat)
polyether
impregnum, hydrophillic4-6 min setting time, most stiff,
gypsum made of? types?
calcium sulfate hemihydrate; type I - rarely used, plaster of paris, type II - ortho casts, not very strong, type III - dentures, type IV - use for stone dies, type V - stone dies, most popular today
PDL types of elastin
No mature elastin, 2 types of immature: oxytalan (regulates vascular flow, parallel to root surface) and eluanin
attached gingiva - narrowest bands
buccal mand canines and 1st premolars, lingual mand incisors and canines
Junctional epithelium
2 basal laminas (internal faces the tooth) and external (faces the connective tissue)
Proliferative cell layer - responsible for most cell divisions and located next to external basal lamina
long junctional epithelium
refers to junctional epithelium in disease, as JE gets longer and moves apically the coronal portion detaches
ANUG (acute necrotizing ulcerative gingivitis)
treponema denticola (spirochete), predominately neutrophils involved
First cells involved in acute inflammation (start of gingivitis)
Polymorphonuclear neutrophils (PMNs)
Acute inflammation
vascular phase (mast cells, basophils and platelets release histamine) and cellular phase (PMNs, then eventually macrophages)
main cell components of chronic inflammation
polymorphonuclear leukocytes (PMLs)
pregnancy gingivitis has increased levels of
prevotella intermedia
Generalized Aggressive Periodontitis
At least 3 permanent teeth other than the 1st molar and incisors are involved
Localized aggressive periodontitis
-Disease that begins at age 11 to 13 with strong familial tendency
- attachment loss at first molars and incisors
- AA bacteria
Hyperthyroidism
Graves disease - most common, goiter and exopthalmos
Plummer's disease - multiple adenomas of the thyroid gland, exopthalmos is rare
Hypothyroidism
myxedema - puffiness of face and eyelids, swelling of tongue and larynx
cretinism - in a child, severe mental retardation, large tongue, under-developed mandible, over-developed maxilla, delayed teeth eruption and deciduous teeth retained longer
hyperparathyroidism
common complaint of kidney stones; osteoporosis and giant cell granulomas, usually caused by adenoma but could occur if there is excessive loss of calcium in the urine (parathyroid will increase in size to compensate)
Clinically - cystic bone lesions(Recklinghausen's)
Hypoparathyroidism
usually due to accidental excision during thyroidectomy, congenital (DiGeorge's syndrome)
Pituitary diseases
excess (from adenoma) - acromegaly (giganitism if before growth plates fuse)
too little - achondroplasia (dwarfism)
osteogenesis imperfecta
inherited condition when bone formation is incomplete, leading to fragile, easily broken bones
blue sclera
bulbous crowns, obliterated pulps, narrow short roots
Hypophosphatasia
Rare metabolic bone disease characterized by the deficiency of alkaline phosphatase
Paget's disease
a bone disease of unknown cause characterized by the excessive breakdown of bone tissue, followed by abnormal bone formation
cotton wool appearance
osteomalacia
disease marked by softening of the bone caused by vitamin D deficiency
Adult or children (Ricket's)
Cleidocranial dysplasia
Delayed tooth eruption
Retention of primary teeth
Supernumerary teeth
hypoplastic/aplastic clavicles
Pierre Robin Syndrome
Syndrome of oral facial abnormalities, micrognathia (a small jaw) and glossoptosis (tongue often blocks airway). Cleft palates are common. Difficulty maintaining the airway frequently causes feeding problems.
cherubism
-benign
-radiolucencies in all 4 quadrants
-symmetrical, firm, jaw swellings of the jaw
-Males
-self limiting... will resolve later in life
-histologically the same as CGCG
-radiotherapy contraindicated
-possible early exfoliation of primary teeth and delayed eruption of permanent
cystic fibrosis
often have stained teeth (due to tetracycline use) and greatly reduced caries risk
multiple neuromas of the oral cavity, medullary carcinoma
Men III syndrome
SSC involving lymphoid tissues in the tonsils
lymphoepithelioma, very poor prognosis
symmetrically widened PDL space around teeth and sun-burst appearance
osteosarcoma [Show Less]