root and pulp morphology Flashcards
How many types of root classifications exist?
There are 4 classes of roots Type 1-IV
Define the types of root classifications
Type 1: one root in one canal
Type 2: 2 separate canals join at one apical foramen
Type 3: 2 separate canals from pulp chamber exit via 2 separate apical foramina
Type 4: one canal from pulp chamber splits into 2 canals and roots exit via 2 apical foramina
T/F apical foramina only exit through the apex of the root
False. Apical foramina could be located to the side of the root apex
T/F. There can be more than 1 apical foramina per 1 root tip.
True. There can be more than foramina at a single root tip – such as the presence of an accessory canal.
Where are pulp horns located and what are their importance?
Pulp horns are located along hte roof of the pulp chamber. The location of pulp horns is important due to the proximity reached during surgical procedures (drilling) importnat not to damage the pulp during restorations, otherwise a simple filling cna turn into a root canal -needing situation.
Where is Type 1 canal found most often? (and what is Type 1)
Type 1 canal means 1 root through 1 canal, and is found most often in MAX incisors and canines
What is Type 3 canal and where can it be found?
Type 3 canal is the occurance of 2 separate roots through 2 separate apical foramina. Type 3 can be found in MAX 1st premolars (think – often have 2 canals! and are transition from anterior to posterior teeth..)
Though it is a small percentage seen here, where can Type 4 root systems be found and what is it?
Type 4 roots is where one root splits into 2 canals and into 2 apical foramina . It occurs with a small incidence in MAND incisors
How many pulp horns do incisors have?
Incisors have 3 pulp horns
How many pulp horns do canines have?
Canines have 1 pulp horn
T/F: The number of lobes = the number of pulp horns
False. The number of lobes does Not equal the number of pulp horns
Usually, how many pulp horns will a peg lateral incisor have?
A peg lateral incisor will generally have 1 pulp horn
How many lobes does a peg lateral incisor form from?
peg laterals form from 1 lobe
What root system are anterior teeth usually?
Type 1 root system- where 1 canal exits via 1 apical foramin
What other systems can be seen in MAND incisors
If not Type 1, MAND incisors can also be Type 2 or 3.. and rarely Type 4.
What root systems are canines?
As anterior teeth, canines re usually a Type 1 root system, though less than 20% of time can be a type 4.
What happens to pulp cavities with age? Why?
With age, pulp cavities get smaller (think sharples describing his elder patients as not needing anesthetic at all..) this is die to the deposition of secondary dentin as we age that narrows the pulp cavity and the development of reparative dentin
What can be done to stimulate dentin growth on exposed tooth surface? When is such a liner used?
A liner containing calcium hydroxide can be used– this liner stimulates dentin growth. A liner is used when during restorative work, the pulp is approximated closely or penetrated. .. a liner is placed to stimulate dentin and protect the pulp. If any blood is seen from inside the tooth prep, means the pulp has been penetrated, ALL Decay needs to be removed, and a direct pulp cap is placed (the liner with calcium hydroxide) . An indirect pulp cap is when MOST decay is removed and pulp is very close but not penetrated. Place liner to help w healing rxn.
What is the general trend for determining the # of pulp horns?
Usually, the # of pulp horns is same as the number of Functional cusps. So MAND 1st premolar w 1 functional cusp = pulp horn, MAX 1st premolar w 2 func. cusps and 2 pulp horns.
A 3-cusp MAND 3nd premolar, likely has how many pulp horns?
A 3-cusp MAND 3nd premolar, likely has 3 pulp horns
T/F MAND canine may have 2 roots? Describe.
True. The MAND canine may have 2 roots, and if so, they are located one facially and one lingually.
If an elderly person has a very large pulp chamber, what could this be indicative of.. why?
If an elderly person is found to have a very large pulp chamber, it might mean that the pulp is dead. This is bc the general trend is to have an increasingly smaller pulp cavity w age, bc dentin builds int he area and narrows the cavity. If cavity is large, lilely dentin is not developing and may mean the pulp in nonvital - dead.
From where does dentin develop?
Dentin develops from odontoblasts and is deposited throughout our lifespan as long as pulp is vital
ALL MAND premolars most often have —- root(s) and ——– canal (s) which is indicative of what kind of root system?
ALL MAND premolars most often have 1 root and 1 canal which is indicative of a Type 1 root system
Usually, MAX 1st premolars have how many root(s)? and arranged how?
Usually, MAX 1st premolars have 2 roots with one canal each (57% of time.. Type 1)
sometime, have only 1 root but still have 2 canals.. 40%
in a rare instancve, 4%, MAX 1st premolars have 3 roots
T/F MAX 1st premolars only ever have 2 roots
False. A small instance 4%, MAX 1st premolars have 3 roots.
What is the most typical arrangement for MAX 2nd premolars?
MAX 2nd premolars most often have 1 root in 1 canal (Type 1)
How many pulp horns would a MAX 1st molar have? Why?
A MAX 1st molar has pulp horns. ! pulp horn per functional cusp. The usually present (70%) cusp of carabelli is nonfunctional and therefore no pulp horn.
How many pulp horns would a MAX 2nd molar have, why?
A MAX 2nd molar would have 3 or 4 pulp horns. Since the small DL cusp is ,missing 33% of the time, it could be a 3 cusp molar and therefore 2 only 3 pulp horns. If all 4 cusps present, then has 4 pulp horns
How many pulp horns does the MAND 1st molar have?
The MAND 1st molar has 5 pulp horns bc it has 5 functional cusps
How many roots and how many canals will MAX molars most often have?
MAX molars most often have 3 roots but 4 openings / orificies in chamber floor– the MB root has 2 canals
How many roots and how many canals do MAND molars have
MAND molars usually have 2 roots but 3 canals ,, the Mesial root has 2 canals (but 3 orifiies in chamber floor)
How does the pulp shape of primary teeth compare to permanent dentition?
Primary teeth have larger pulp chambers that are much closer to the surface (bc dentin and enamel are thinner. So CAREFUL when restoring primary teeth. Be aware that infection of the tooth can easily reach the pulp since has thin barriers
Knowledge of shape and location of pulp is critical for restoration (to avoid) and endodontics to properly repair. T/F
True. Knowledge of pulp cavity and alignment of root canals and roots is ciritical to avoid pulp during restoration and to properly prepare canals in endodontics
How can a dentist check if tooth pain in root is reversible or irreversible?
Use an ice cube, if pain comes and goes - could be reversible. If pain is constant - likely needs a root canal
What is it called when the pulp is inflammed and cannot heal?
This is a case of pulpal disease.. when the pulp is inflammed and cannot heal it is called irreversible pulpitis (recall, -itis = inflammed)
T/F Periapical disease is a change in the apex of the root
True, Periapical disease is a change in the apex of the root
What is periapical radiolucency?
Periapical radiolucency is a dark area on a radiograph at the apex of a root indicative of bone loss
What is a granuloma?
A granuloma is inflammed tissue encapsulated in a fibrous capsule
What is a cyst?
A cyst has liquid content
What is necrosis
necrosis is tissue death– in terms of endodontics - pulp death (recall, a large pulp chamber in an elderly person could be indicative of pulp necrosis)
T/F pulpal / periapical disease is often caused by decay that has entered the pulp.
True, pulpal / periapical disease is often caused by decay that has entered the pulp.
Describe the process, generally, of a root canal
- First, an opening is created to access the root canal – do not want to open up the whole tooth, so knowledge of orifice and root location = key.
- Locate the canal orificies (on the pulp chamber floor)
- CLean out each canal by removing the pulpal tissue
- Fill clean canals (with gutta percha)
What is gutta percha?
Gutta percha is a fill material used to fill the cleaned canals left from a root canal
Is a crown always a necessary follow-up to a root canal?
No, a crown is not always necesary. If enough tooth structure was maintained after a root canal procedure, a crown will not be necessary..
in primary teeth, crowns not recommended as follow-up. In anterior teeth, it depends on the amt of tooth structure remaining
- on molars, a post and crown could be a good idea
The following describes what kind of tooth:
- cervical root and chamber outlines are triangular
- cingulum is distal
- 1 root canal
- no root depressions and mesial is flatter
- cervical root and chamber outlines are triangular
- cingulum is distal
- 1 root canal
- no root depressions and mesial aspect is flatter
these describe MAX central incisors
what teeth most often only have 1 root, and 1 canal?
Anterior teeth most often have 1 root and 1 canal:
MAX and MAND C and L incisors, MAX canines, and MAND canines (70-80%)
MAND 1st premolars (1 canal 70% of time)
MAND 2nd premolars, 1 canal usually
MAX 2nd premolars 1 root, 1 canal 60% of time
REVIEW pages 6-9 of ROOT MORPHOLOGY packet
know the shapes and outlines of the teeth and how to assign to belonging tooth
How many roots and canals does a MAX 2nd premolar usually have?
A MAX 2nd premolar usually has one root and one canal.
How many pulp horns do incisors have?
Incisors usually have 3 pulp horns (think to remember: (3 mamelons..)
How many roots do MAX 1st molars usually have? How many orifices
MAX 1st molars usually have 3 roots but have 4 orifices – 2 orificiesin the MB root
HOW many roots do MAX 2nd molars usually have? How many orifices?
MAX 2nd molars usually have 2 roots but 3 orifices (2 orifices in the larger mesial root)
