PEDO pt 1 Flashcards
initiation (bud stage) of primary teeth occurs in week ___ of embryonic life
6
which teeth arise from the dental lamina? where do the other teeth arise from?
- all primary teeth and permanent molars
- all permanent incisors, canines, and premolars arise from their primary predecessor
failure of what stage of development results in congenitally missing teeth?
- initiation (bud stage)
- alternatively, excessive budding results in supernumerary teeth
what are the stages, in order, of tooth development?
- initiation (bud stage)
- proliferation (cap stage)
- histodifferentiation and morphodifferentiation (bell stage)
- apposition
- calcification
during the proliferation (cap) stage, peripheral cells of the cap form the ___ and ___
inner and outer enamel epithlium
failure in the proliferation results in ___
congenitally missing teeth
excessive proliferation results in ___
a cyst, odontoma, or supernumerary tooth, depending on the amount of cell differentiation
during the histodifferentiation and morphodifferentiation (bell) stage, cells of the dental papilla differentiate into ___, and cells of the inner enamel epithelium differentiate into ___
- odontoblasts
- ameloblasts
failure in histodifferentiation results in ___, and failure in morphodifferentiation results in ___
- structural abnormalities of the enamel and dentin (amelogenesis imperfecta, dentinogenesis imperfecta)
- size and shape abnormalities, such as peg lateral incisors and macrodontia
what happens during the apposition stage?
ameloblasts and odontoblasts deposit a layerlike matrix
disturbances in apposition result in ___
- incomplete tissue formation
- for example, an intrusive injury to a primary incisor may disrupt enamel apposition and result in an area of enamel hypoplasia
enamel is composed of ___% inorganic material and ___% organic material and water
96%, 4%
where does calcification begin?
begins at cusp tips and incisal edges and proceeds cervically
what can cause hypocalcification?
localized infection, trauma, and excessive systemic fluoride ingestion
what are the approximate calcification times for primary teeth?
- central incisor 14 weeks in utero
- first molar 15 weeks in utero
- lateral incisor 16 weeks in utero
- canine 17 weeks in utero
- second molar 18 weeks in utero
what are the approximate maxillary eruption times for primary teeth?
- central incisor 10 months
- lateral incisor 11 months
- first molar 16 months
- canine 19 months
- second molar 29 months
- a 6 month variation in eruption time is considered normal
what are the approximate mandibular eruption times for primary teeth?
- central incisor 8 months
- lateral incisor 13 months
- first molar 16 months
- canine 20 months
- second molar 27 months
- a 6 month variation in eruption time is considered normal
what are the approximate calcification times for permanent maxillary teeth (excluding 3rd molars)?
- first molar birth
- central incisor 3-4 months
- canine 4-5 months
- lateral incisor 10-12 months
- first premolar 1.5 years
- second premolar 2 years
- second molar 2.5 years
what are the approximate calcification times for permanent mandibular teeth (excluding 3rd molars)?
- first molar birth
- central incisor 3-4 months
- lateral incisor 3-4 months
- canine 4-5 months
- first premolar 1.75 years
- second premolar 2.25 years
- second molar 2.75 years
what are the average eruption times for maxillary permanent teeth?
phone number: 781-0062
what are the average eruption times for mandibular permanent teeth?
phone number: 679-0161
eruption of a tooth begins when the crown has completed ___
calcification
typically, it takes ___ years for most crowns to complete formation except for first molars and cuspids, which take how long?
- 4-5 years
- first molars take 3 years
- cuspids take 6 years
it takes approximately ___ years from start of calcification to root completion, except for canines, which take how long?
- 10 years
- canines take 13 years
teeth typically erupt through the bone with how much root formation? they typically erupt through gingiva with how much root formation
- 2/3 root formation for bone
- 3/4 root formation for gingiva
the interval between crown calcification and full interdigitation is about ___ years
5
eruption to root completion takes approximately ___ years
3
what are the most common eruption sequences for maxillary and mandibular teeth?
- maxilla: first molar, central, lateral, first premolar, second premolar, canine, second molar
- mandible: first molar, central, lateral, canine, first premolar, second premolar, second molar
supernumerary teeth affect which gender more, and what percent of the population is affected?
- M:F 2:1
- 3%
what are the most common supernumerary teeth?
mesiodens, most of which are palatal
what are the two classifications of supernumerary teeth?
- supplemental (has typical anatomy)
- rudimentary (conical, tuberculate, or molar-shaped)
excluding 3rd molars, what is the incidence of hypodontia (congenital absence)?
1.5-10%
what are the most common congenitally missing teeth in order, excluding 3rd molars?
- mandibular second premolar
- lateral incisor
- maxillary second premolar
microdontia is seen in what developmental defects?
- ectodermal dysplasia
- chondroectodermal dysplasia
- hemifacial microsomia
- down syndrome
- another example of microdontia is a peg lateral
macrodontia is seen in what developmental defects?
facial hemihypertrophy and otodental syndrome
___ is the union of two primary or permanent teeth (which is it more common in?)
fusion, more common in primary teeth, almost always in anterior teeth
describe the pulp chambers/canals of fused teeth
they have two pulp chambers and two pulp canals
between tooth fusion and tooth gemination, which one has a normal number of teeth, and which has one less than normal?
- gemination has a normal amount
- fusion has one less
___ is the division of a single tooth bud, resulting in a bifid crown, and is more common in ___ teeth
- gemination (have a single pulp chamber)
- primary
___ is an anomaly of tooth shape and results in an extra cusp
- dens evaginatus
- aka talon cusps in incisors
why should care be taken with any operative procedure on a tooth with dens evaginatus?
the anomaly has enamel, dentin, and pulp
dens invaginatus (also called ___) is caused by ___ and has been termed “tooth within a tooth”
- dens in dente
- invagination of the inner enamel epithelium
dens invaginatus most commonly occurs in what teeth?
permanent maxillary lateral incisors
what is the ideal treatment for dens invaginatus?
preventive treatment; small restoration or sealant
___ is characterized by vertically long pulp chambers and short roots
taurodontism
when is taurodontism clinically significant?
if pulp therapy is required or during the exfolation process
a dilacerated tooth usually occurs as the result of ___
- an intrusive or displacement injury to a primary incisor
- it is also a consistent finding in congenital ichthyosis
enamel hypoplasia may be due to what two main factors?
environmental or genetic
what are the environmental factors that may be responsible for enamel hypoplasia?
- systemic diseases, especially fevers
- fluorosis
- nutritional deficiencies, especially vitamins A, C, D, calcium and phosphorus
- neurologic defects (sturge-weber syndrome and cerebral palsy)
- cleft lip and palate, radiotherapy and chemo, nephrotic syndrome, lead poisoning, rubella embryopathy
- local infection, trauma
what are the genetic factors that may contribute to enamel hypoplasia?
amelogenesis imperfecta
___ refers to quantity deficiencies of enamel, whereas ___ refers to quality deficiencies of enamel
- hypoplasia
- hypocalcification
what are the environmental and genetic factors that contribute to enamel hypocalcification?
- environmental are the same as for hypoplasia
- genetic amelogenesis imperfecta, hypocalcified type (normal thickness of enamel but is poorly calcified and fractures easily)
what is the incidence of amelogenesis imperfecta?
1/14,000
amelogenesis imperfecta is related to the enamel only and is dependent on ___
the developmental stage of enamel
what is the pulp and root morphology in amelogenesis imperfecta?
normal
what is the treatment for amelogenesis imperfecta?
- depends on the type and severity
- severe cases, especially in terms of quality of enamel, require full-coverage restorations
- veneers may be appropriate in some hypomaturation and hypoplastic types
what is the incidence of dentinogenesis imperfecta?
1/8000
dentinogenesis imperfecta occurs at what stage of tooth development?
- histodifferentiation stage
- predentin matrix is defective resulting in amorphic, atubular dentin
which teeth are affected by dentinogenesis imperfecta?
primary and permanent
what are the characteristics of dentinogenesis imperfecta?
- teeth are reddish brown to gray opalescent color
- roots are slender
- pulp chambers and canals appear small or absent
- enamel chips away easily
- teeth can become severely abraded
what is the treatment for dentinogenesis imperfecta?
- may include full coverage crowns to prevent severe abrasion
- bonded veneers on anterior teeth have proven successful in some cases that are less severe
which teeth are affected by dentin dysplasia?
primary and permanent
what are the two types of dentin dysplasia?
shields type 1 and type 2
which type of dentin dysplasia presents with the following:
- normal crown anatomy
- color is closer to normal than dentinogenesis imperfecta
- short, pointed roots
- absent pulp chambers and canals, primary and permanent teeth
- multiple periapical radiolucencies, primary and permanent teeth
shields type 1
which type of dentin dysplasia presents with the following:
- primary teeth appear similar to dentinogenesis imperfecta
- permanent teeth have normal color, pulp stones, thistle tube shaped pulp chambers, with no periapical radiolucencies
shields type 2
other than dentinogenesis imperfecta and dentin dysplasia, what other conditions affect dentin?
- regional odontodysplasia
- vitamin D-resistant rickets
- hypoparathyroidism
- pseudohypoparathyroidism
what are the frankl behavioral rating scales used in pediatric dentistry?
- rating 1 - definitively negative and refusal of treatment
- rating 2 - negative reluctance to accept treatment
- rating 3 - positive acceptance of treatment, sometimes cautious
- rating 4 - definitively positive good rapport with dentist
___ is a procedure that slowly develops behavior by reinforcing successive approximations to a desired goal
behavior shaping
___ is a psychological strategy that uses some form of negative stimulus with the purpose of extinguishing or improving negative behavior
- aversive conditioning
- should always be followed by positive reinforcement
world-wide, what percent of all school-age children have ADHD?
2-9.5%
what are the common examples of adverse reactions with methyphenidate (concerta, ritalin, metadate)?
nausea and hypertension
what are the common examples of adverse reactions with atomoxetine (strattera)?
hypertension, dry mouth, nausea
what are the common examples of adverse reactions with amphetamine/dextroamphetamine (adderall)?
hypertension, headache, nausea, dry mouth
what is the pulpal and soft tissue duration of 2% lidocaine w/1:100,000 epi?
- pulpal: 60 min
- soft tissue: 3-5 hours
what is the pulpal and soft tissue duration of 3% mepivacaine?
- pulpal: 20-40 min
- soft tissue: 2-3 hours
what is the pulpal and soft tissue duration of 4% prilocaine w/1:200,000 epi?
- pulpal: 60-90 min
- soft tissue: 3-8 hours
outline the steps to calculate maximum dose and cartridges of local anesthetics
- convert pt weight to kg (divide weight in lbs by 2.2)
- multiply weight in kg by the max recommended dose of LA to obtain max mg dose
- calculate number of mg per cartridge by multiplying the % of LA times 10, then multiplying by the size of the cartridge (usually 1.8mL)
- divide max mg dose by the number of mg per cartridge to obtain max allowable cartridges of anesthetic
describe the anatomic landmark in children for inferior alveolar nerve blocks
- in the primary dentition patient, the mandibular foramen in located lower than the plane of the occlusion (lower than adults)
- the syringe should bisect the primary molars on the opposite side of the injection
overdosage of local anesthesia can cause what?
- central nervous system complications, including dizziness, blurred vision, seizures, CNS depression, and death
- cardiac complications may include myocardial depression
what are the physiologic differences between children and adults relative to nitrous oxide administration?
-basal metabolic activity and heart rate are higher in children
-blood pressure is lower in children
-higher risk of airway obstruction and desaturation in children
drug effects are more variable in children
the administration of nitrous oxide at levels less than ___% (with no combination with other sedative/narcotic/depressant agents) is considered to be minimal sedation
50%
what are the purposes of nitrous oxide sedation?
- reduce fear, apprehension, or anxiety
- raise pain reaction threshold
- reduce fatigue
- enhance communication
- increase tolerance for longer appointments
- help in care of developmentally or physically challenged
- decrease gagging reflex
a minimally sedated patient may have temporary ___ and ___ impairment, but ___ and ___ function is unimpaired
- cognitive and coordination
- heart and lung
___ is a measure of potency and is the concentration required to produce immobility in 50% of patients
minimum alveolar concentration
what is the minimum alveolar concentration of nitrous oxide?
105%
what are the four plateaus of stage I anesthesia (analgesia)?
- parasthesia - tingling of hands and feet
- vasomotor - warm sensations
- drift - euphoria, pupils centrally fixed, sensation of floating
- dream - eyes closed by open in response to questions, difficulty in speaking, jaw sags open
the total flow rate of nitrous oxide is ___L/min for most children
4-6
when administering nitrous oxide, the percentage of nitrous oxide is increased at increments of ___% until the drift plateau (euphoria, pupils centrally fixed, sensation of floating) is reached
10-20%
maintenance dose of nitrous oxide during an operative procedure is typically about ___%
30%
what is the most common complication with nitrous oxide?
nausea with or without vomiting
what are the signs of saturation on a child receiving nitrous oxide?
- reminding child continuously to hold mouth open
- no response to questions
- agitation
- sweating
- nausea
- unconsciousness
what is diffusion hypoxia?
- when nitrous oxide is discontinued, there is a high outpouring of nitrous oxide from the tissues into the lung
- this can dilute available oxygen in the lungs
- although diffusion hypoxia is rare, patients should be given 100% oxygen for 3-5 minutes after nitrous oxide procedures
what are the air space contraindications for nitrous oxide?
- patients with blocked eustachian tube
- pneumothorax
- pneumoperitoneum
- sinusitis
- any rigid, noncompliant air space can lead to increased pressure with nitrous oxide
should nitrous oxide be used on pregnant patients?
no
is nitrous oxide indicated in patients with significant emotional disturbances?
no
patients with ___ dependencies, some ___ infections, and ___ deficiency should not be given nitrous oxide
- drug
- upper respiratory
- methylenetetrahydrofolate reductase
nitrous oxide is contraindicated in patients treated with ___
bleomycin sulfate
before administration of nitrous oxide, a physician consultation should be obtained for patients with what significant medical conditions?
- obstructive pulmonary disease
- congestive heart failure
- sickle cell disease
- acute otitis media
- tympanic membrane grafts
compare enamel thickness, pulp chamber size, and pulp horn location of primary vs permanent teeth
primary teeth have thinner enamel, larger pulp chamber, and pulp horns are closer to the surface of the tooth
compare the direction of enamel rods, crown height, and interproximal contacts of primary vs permanent teeth
- in primary teeth, the enamel rods in the gingival 3rd slope occlusally instead of cervically as in permanent teeth
- in primary teeth, the crown is relatively shorter and has a greater constriction in the cervical region, and the interproximal contacts are broader and flatter than permanent teeth
compare enamel and dental shades, and occlusal table of primary vs permanent teeth
- enamel and dentin shades of primary teeth are generally whiter than permanent teeth
- the occlusal table is narrower on primary molars
describe preparation depths for restoring primary molar teeth
- 0.5mm into dentin (total depth of preparation is typically 1.5mm)
- no. 330 bur is 1.5mm, and no. 245 bur is 3mm (these can aid in establishing proper depth of the preps)
when restoring primary molars, why should line angles be rounded?
to decrease internal stresses in the restorative material and help prevent breakage with the smaller primary teeth
when restoring primary molars, the buccal and lingual walls should ___ occlusally, and the isthmus width is ___ the intercuspal dimension
- converge
- one third
describe the steps for a composite resin crown in anterior cases where there is significant incisal edge loss
- prep includes caries removal, M and D IPR, and placing an undercut area approx. 1mm incisal and following the free gingival margin
- a celluloid crown form is trimmed and adapted to cover the cervical margins, and at least one vent hold is created on the incisal edge
- crown form is filled with composite and seated
describe how prefabricated zirconia crowns should fit for primary teeth
they should fit passively because they do not flex the way stainless steel crowns do
what are the four options a dentist has if a primary tooth has pulp involvement?
- pulp capping
- pulpotomy
- pulpectomy
- extraction
why is pulp therapy generally contraindicated in children who have serious illnesses?
extremely serious complications secondary to acute infection can arise should the pulp therapy fail
patients with what conditions is pulp therapy contraindicated for?
- susceptible to bacterial endocarditis
- leukemia
- nephritis
- cancer
- depressed polymorphonuclear leukocyte and granulocyte counts
what are the important clinical signs that a patient needs pulp therapy?
- mobility
- swelling or fistula
- furcation radiolucency
- percussion or palpation sensitivity
- spontaneous pain
is a vital pulpotomy indicated for a tooth with mobility? why or why not?
no, because it indicates loss of vitality if mobility is due to bone destruction, root destruction, or both
why is the vital pulpotomy technique inappropriate for a tooth with swelling or a fistula?
it indicates necrotic pulp
what does a furcation radiolucency indicate?
- necrotic pulp
- vital pulpotomy is inappropriate
- pulpectomy may be appropriate if the tooth does not demonstrate internal or external root resorption
what does percussion or palpation sensitivity indicate?
- at least advanced pulpal inflammation
- pulpotomy may not be advisable
what does spontaneous pain indicate?
- at least advanced pulpal inflammation
- other indicators should be used to determine treatment of the tooth, but pulpotomy may not be advisable
what are the indications for indirect pulp cap?
- asymptomatic
- no radiographic evidence of pathosis
- minimal caries in an area that, if caries were removed, would result in a pulp exposure
what is the procedure for an indirect pulp cap?
- caries removal, leaving caries that would expose the pulp
- calcium hydroxide layer or base cement, or both
- restoration of the tooth
- wait 6-8 weeks
- re-enter and remove remainder of caries (some clinicians avoid this step and proceed with the restoration)
what are the indications for a direct pulp cap?
- very small, pinpoint exposure only
- noncarious exposure only
- asymptomatic
why might a direct pulp cap not be recommended with primary teeth?
risk of internal root resorption
what is the procedure for a direct pulp cap?
- place a calcium hydroxide layer
- restore the tooth
what are the indications for a pulpotomy?
- vital primary tooth with carious or accidentaly exposure
- clinical signs of a normal pulp canal
- the tooth must be restorable
what is the procedure for a pulpotomy?
- remove superficial and lateral decay
- remove roof of the chamber
- extirpate coronal pulp, no. 4 round bur, slow speed, light pressure
- dry cotton pellets to arrest pulpal hemorrhage
- formocresol application for 5 minutes; if hemorrhage cannot be controlled, consider pulpectomy of two-visit pulpotomy
- ZOE buildup
- SSC
what is the success rate of pulpotomies?
70-97%
what are the common medicaments used for pulpotomies?
- formocresol
- ferric sulfate
- mineral trioxide aggregate
what is the most commonly used medicament for pulpotomies on primary teeth?
buckley’s formocresol
what is the composition of formocresol?
- 35% cresol, 19% formaline in aqueous glycerin
- a 20% solution produces equivalent results as full strength
formocresol acts by ___
direct contact
which medicament commonly used for pulpotomies in primary teeth has possible toxic effects?
formocresol
how does ferric sulfate compare to formocresol?
- success rates are comparable
- ferric sulfate is less toxic
how does mineral trioxide aggregate compare to formocresol?
generally shows higher success rates for pulpotomies than formocresol
what are the indications for a pulpectomy in a primary tooth?
- necrotic or chronically inflamed, strategically located tooth with accessible canals
- essentially normal supporting bone
what are the contraindications for a pulpectomy on a primary tooth?
- nonrestorable tooth
- internal or external root resorption
- teeth without accessible canals (commonly first primary molars)
- significant bone loss
what is the technique for a pulpectomy procedure?
- remove coronal pulp as for pulpotomy
- irrigate chamber with sodium hypochlorite or sterile saline, dry with cotton pellet
- remove radicular pulp tissue with small file or barbed broach
- obtain test lengths 1-2mm short of apex
- enlarge canal approximately 3 sizes
- wash frequently with sodium hypochlorite or sterile saline
- dry with paper points
- fill/obturate
what are the obturation methods for pulpectomy procedures on primary teeth?
- pressure syringe
- use paper point or file and coat the walls with a creamy mix of ZOE
- fill with creamy ZOE mix, starting 1-2mm from apex - condensation
- coat walls with creamy ZOE mix
- continue mixing ZOE to a condensable thickness, roll into points, and condense with small endo or amalgam pluggers
if caries extends into the pulp, what treatment should you consider if there is no furcation involvement?
the tooth is likely vital, so a vital pulpotomy is generally appropriate if the tooth is restorable
if caries extends into the pulp of a first primary molar, what treatment should you consider if there is furcation involvement?
extraction should be strongly considered because of the difficulty of adequately removing diseased pulp tissue in this tooth
why should a dentist consider the restorability of a tooth in terms of drift of adjacent teeth?
occasionally an adjacent tooth may tip into a carious defect, preventing an appropriate adaptation of a stainless steel crown
generally, if a tooth has internal or external root resorption, it should be extracted. what is an exception to this rule?
- if the tooth is located strategically
- for example, a second primary molar with mild-moderate root resorption on a 5-year old patient may be considered for pulp treatment; the purpose of the treatment is to maintain space until first permanent molar erupts, then extract the primary molar and place a space maintainer
