Week 5-6 of palatal formation
primary palate
Primary palate
Formed by intermaxillary segment from fused medial nasal processes
Week 6-12 of palatal formation
Secondary palate
Secondary palate
Formed by fused palatal shelves from maxillary processes
Week 12 of palatal formation
Final palate
Final palate
Formed by fusion of all three processes
Intermaxillary segment
gives rise to the primary palate
Intermaxillary segment
arises as a result of fusion of the 2 medial nasal processes internally
Primary palate
primitive"; anterior 1/3 of palate; located in front of incisive foramen & includes central & lateral incisors
Secondary palate
posterior 2/3 of palate; palatal shelves flip horizontally to fuse; includes canines & posterior teeth; gives rise to soft palate & uvula
Median palatine raphe
sutures"; created by maxillary palatal shelves fusion
What forms the palatal muscles?
mesenchyme from the 1st and 2nd brachial arches
What do the muscles of soft palate aid in?
Speech, eating, etc.
Nasopalatine canals
Canal present at the junction of primary & secondary palates
Incisive foramen
nasopalatine canals become this
Cleft palate
@ week 6!-failure of palatal fusion results in this; can be unilateral or bilateral
12th week
when cleft palate is formed
Nasal septum
formed from the medial nasal process; week 5-12; deviated septum could occur at this time
Tongue
muscles from this structure begin developing from week 4 to 8
Body of tongue
developed at week 4 to 8 by tuberculum impar & lateral lingual swellings
Completed tongue
developed by week 8 by merging of anterior swellings of body & copula of base
Copula
immediately posterior to the fused anterior swellings
Sulcus terminalis
on posterior part of tongue where body & base are fused
Epiglottis
fused at the 8th week by swellings
Ankyloglossia
tongue tied; result of a short attachment of the lingual frenum that extends to the tongue apex; usually clipped at birth
Morph
change in shape
Cap stage
primordium of tooth
Stellate reticulum
star-shaped
Stellate reticulum & stratum intermedium
located between inner & outer enamel cells
Odontogenesis
process of tooth development
Primary dentition
dentition that begins to form at week 6-7
Dental lamina
formed during the later part of the 7th week, oral epithelium grows deeper into the ectomesenchyme & is induced to produce this; where "seeds" are placed
Initiation stage of tooth development
1st stage; @ week 6; oral epithelium forms maxillary and mandibular arches
Bud stage of tooth development
2nd stage; @ beginning of week 8; primary dentition. extensive proliferation of dental lamina into buds with 3-dimensional oval masses penetrating into the surrounding ectomesenchyme; 10 buds each arch become primary teeth
Cap stage of tooth development
3rd stage; @ week 9-10; primordium of the tooth germ; enamel organ; enamel knot; dental papilla gives rise to dentin & pulp; dental sac(follicle)
Bell stage of tooth development
4th stage; @ week 11-12; continuation of proliferation, differentiation, morph of cap stage.
Ameloblasts
inner most cells that secrete enamel
Epithelium
outer enamel cells that protect inner enamel organ
Development/disturbances of initiation stage
supernumerary; anodontia; oligodontia; partial anodontia; ectodermal dysplasia associated with anodontia
Development/disturbances of bud stage
macrodontia & microdontia
Development/disturbances of cap stage
Dens in dente; gemination; fusion; tubercle
Dens in dente
developmental disturbance that happens if enamel gets into papilla; especially maxillary incisors & laterals
Gemination
developmental disturbance that happens if tooth has 2 crowns & 1 large, single root, 1 pulp(on x-ray)
Fusion
developmental disturbance that happens when 2 teeth fuse and become 1 crown with 2 pulp cavities(on x-ray)
Tubercle
developmental disturbance that happens when there is a small, round enamel extension forming extra cusps
Enamel organ
produces enamel
Dental papilla
gives rise to the dentin & pulp
Dental Sac
pac": give rise to the periodontal ligament, alveolar process, & cementum; increases the amount of collagen fibers forming around the enamel organ
Anterior permanents & then premolars
which teeth begin forming around the 10th week during the cap stage
Succedaneous teeth
teeth replaced by permanent teeth
Nonsuccedaneous teeth
teeth that DO NOT replace teeth
Outer enamel epithelium
cuboidal cells of enamel organ that serves as a protective barrier for enamel organ
Inner enamel epithelium
tall, columnar cells of enamel organ that will differentiate into ameloblasts that form enamel matrix
Stellate reticulum
more outer "star-shaped" cells in many layers, forming a network within the enamel organ; supports the production of enamel matrix
Stratum intermedium
more inner compressed layer of flat to cuboidal cells; supports the production of enamel matrix
Basement membrane
between the inner & outer layer of epithelium
Outer cells of dental papilla
layer of cells nearest the inner enamel epithelium of the enamel organ; a basement membrane in between this layer and the inner enamel epithelium; will differentiate into odontoblasts that form dentin matrix
Central cells of dental papilla
cells that will differentiate into pulp tissue
HERS
Hertwig root sheath
ERM
Epithelial rests of Malassez
Epithelial Rests of Malassez
disintegration of Hertwig Root Sheath
Amelogenesis
The appositional growth of enamel matrix, laying it down on their side of the now disintegrating basement membrane
Ameloblasts
begin amelogenesis
Tomes process
Structure that enamel matrix is secreted from; forms the dentinoenamel junction
Development/disturbance of apposition/maturation
Enamel dysplasia, Enamel hypocalcification, enamel hypoplasia, amelogenesis imperfecta, dentinogenesis imperfecta
Enamel dysplasia
local=trauma/infection & systemic=whole dentition
Enamel hypocalcification
dental fluorosis=too much fluoride; "sparkle spot or Turner spot
Enamel hypoplasia
less" quantity of enamel laid down; Hutchinson's incisors & Mulberry molars
Syphilis
related to Mulberry molars & Hutchinson's incisors
Amelogenesis imperfecta
NO ENAMEL; can affect all teeth of both dentitions, hereditary etiology
Dentinogenesis imperfecta
Dentin dysplasia; interference with the metabolic processes
Cervical loop
Most cervical part of the enamel organ responsible for root development and forms Hertwig Root Sheath
Epithelial Rests of Malassez
during root formation when basement membrane disintegrates, as does the entire HERS
Developmental disturbance during root development
Concrescence; usually maxillary 1st molars
Concrescence
excess cementum; resulting in an enamel pearl
Odontoblastic process
cellular extensions in length of the predentin
Dentinal Tubule
mineralized cylinders
Active eruption
actual vertical movement of the tooth
Passive eruption
with aging; gingiva receeds & looks like tooth is erupting but it's actually not
Avulsed tooth
removed from socket due to injury
Moist
you must keep an avulsed tooth_____________
Dentigerous cyst
partially erupted tooth; produced from REE(reduced enamel epithelium
Bohn Nodule
reminents of dental lamina & salivary glands in maxillary alveolar ridge(bone)