radiology II Flashcards
*Enamel is the outer layer of the crown of each tooth we can see the difference in densities between Enamel and Dentin which is darker.
Enamel is a radiopaque structure (white Structure) and Dentin is a radiolucent structure in comparison to enamel although both are radiopaque, dentin is just less radiopaque then enamel.
green-*Amalgam Restoration, it looks very very bright on the radiograph because metals absorb the X-rays.
blue-*Pulp Chamber is a concavity that is radiolucent aka dark as most of the times it has an oval elongated shape and on the molars it follows somewhat the anatomy of the cusp
*Pulp chamber when we were young were really big and wide as seen in this figure, this is why in young people’s teeth when they get dental decay/ caries the damage can go much faster to the pulp due to their wideness as the pulp chamber can reach the cusps. This why younger peoples Teeth are more sensitive.
red-Root Canals Are very thin radiolucent elongated structures that start from the pulp chamber and go all the way to the apex
The pulp chamber is very smaller due to the formation of secondary dentin that is made to protect the teeth from a stimuli, so as we grow older the pulp chamber goes smaller.
green-The Apex is very narrow and the roots are converging towards the apex.
When the teeth are not fully erupted, yet the apexes are really wide and this is a way to distinguish younger individuals to older individuals. Wide Apexes
All restorations are opaque and that is how they are identified.
Depending on the material some materials are more opaque than the others
red-*Amalgam Restoration is the most opaque restoration
green-*Fused Metal Restorations (porcelain) they show 2 different margins almost like the cup shape (opaque) and then above the cup we can see almost-enamel like structure.
The cup is metallic and porcelain is fused to the metal.
light blue-*Composite Restorations, Less opaque restorations that look like enamel, most of the times used for the front teeth.
blue-Long time ago, the composite restorations used to be very radiolucent, and we couldn’t really tell if it was a cavity or a restoration by looking at the radiograph, that’s why they created the composite restorations we use today that include additives in order to make it more opaque and identify it by looking at the radiograph.
which are the Supporting Structures?
- Lamina Dura
- Periodontal Ligament Space
- Alveolar Crest
- Cancellous Bone
red-*Lamina Dura means the dense plate, on the radiograph it is seen as this thin radiopaque line surrounding the root of the teeth.
The integrity of the lamina dura is very important for the detection of disease that is why we observe it very carefully. Lamina dura continues on the top to form the crest of the alveolar bone sometimes we might not be capable to see it. When the lamina dura is completely lost then we have to be suspicious of disease.
green-*The Periodontal Ligament space is the thin radiolucent line between the lamina dura and the root of the tooth. It is a package of ligaments, which connect the lamina dura to the root of the tooth. (mobile area in the root socket)
Sometimes we can see a double layer of lamina dura
blue-*Widening of the PDL
yellow-*Deeply Decayed (carious Lesion) that moved to the root of the tooth and went through the root canal and then reached the apex which is deeply rich with blood vessels and they are being cultivated which leads to a bit of bone loss.
Sometimes we cannot see the Lamina Dura not due to disease but due to an incorrect angulation** as shown here, we can see as if the restorations are connected but in fact, they are not, we can see this due to the **incorrect horizontal angulation. If we repeat the radiograph with the right angulation, we will be capable to see the lamina dura very well.
red-Alveolar Crest which is a thin part of bone identified between the two neighboring teeth. The alveolar crest is supposed to be reaching up to 1-1.5mm below the cemento-enamel junction is where the enamel
yellow:*Cemento-enamel junction is the area where the enamel of a tooth ends and the alveolar crest is 1-1.5cm below.
green-*The alveolar crest is a cortical bone so it is contoured with lamina dura.
blue-*When we do not see the alveolar crest completely this means that we have an early stage of periodontal disease.
Sometimes the alveolar crest might not show for two reasons:
- red-The horizontal angulation might be wrong
- purple-It may be burned out by when it’s very very thin like here, we don’t see at all the alveolar crest, and this is due to the bone to be very thin and the intensity of the x-ray burned out the alveolar crest so we can’t see it on the X-ray but it’s there in real life.We have different tools to recognize the alveolar crest such as the periodontal probe which help us find out if we have a periodontal disease or not.
red-tubercle
The cancellous bone is the maxillary and mandibular archs are made of cancellous and cortical bones.
Cortical bone is very thin and is surrounding the entire bone and the cancellous bone is the content surrounded by the cortical bone.
The Cancellous is composed of tubercle which are the very small group of bone cells, the tubercle are very sparse in the mandibular arch and not as dense as in the maxillary arch And much wider and almost horizontally oriented and denser on the mandibular bone.
red-the median palatine suture is this thin radiolucent line splitting the maxilla in half into 2 maxillas. The borders of the 2 maxilla are dense because the border of the 2 bones is cortical bone.
The Intermaxillary** and **median palatine suture is always identified in between the 2 central incisors.
blue-The nasal cavity is most of the times is composed of 2 dense lines forming an angle converging to the anterior nasal spine.
The nasal spine spine forms the floor of the nasal cavity.
The nasal spine is different from patient to patient, as we can see here it can be triangular and some other times it can be rhomboid shape.
red-Nasal Septum
green-The right and left nostrils
Here we can see how we place the radiograph film and what we get upon placing it in this position.
rede-These bony chambers are the inferior nasal concaves they are the bony structures that separate the nasal cavity in smaller chambers. The radiograph cannot depict them. But …(continued on the lower box )
However, if we move the radiograph slightly to the right side the radiograph will depict the bony fragment.
yellow->*Soft Tissue
Therefore, simply by moving slightly the radiographic film we can see more information.
red-The incisive foramen: triangular low-density area, which goes with the palatine suture.
yellow-In this radiograph we cannot really see the incisive foramen what we are seeing here is the projection of the soft tissue of the nose, since they are is very radiolucent.
red-*Incisive Foramen
green-*Walls of the nasal palatine canal, The nasal palatine canal starts from the floor of the nasal cavity and extends low to the oral cavity. And exits from the incisal foramen.
yellow-*Sometimes we can see the 2 openings of the nasal palatine canal (superior foramina) which are converging and forming the nasal cavity reaching the incisive foramen
blue-*Right and left floor of the nasal cavity
*When the radiograph is focused on one side e.g. the right side so we will see only the part of the right nasal cavity.
red->We can see the borders of the right nasal cavity (floor). yellow->Right Inferior Nasal Concave
green->Anterior Nasal Spine
blue->Soft Tissue line almost like an arch line and this is the soft tissue of the nose.
*On the next picture we have a different angulation and a different side, thus the nasal cavity isn’t depicted as clearly as in the first picture
red->*Floor of the Nasal Cavity
Maxillary sinus is bordered by the floor of the Nasal Cavity. It’s an air cavity which makes the space look darker (it’s not denser)
green->*Coinciding with the maxillary sinus is a dense U shaped structured known as the Zygomatic Process of the maxilla more generally, it’s the frontal part of our cheek
yellow->*Floor of the left maxillary sinus
red->*Diagonal line which almost make the half of the radiograph more opaque in comparison to the frontal part. This line is the Nasolabial fold which is a soft tissue line, and may show in our radiograph (this line is mostly depicted upon doing angry or annoyed face)
red->*Floor of the maxillary sinus forming a chamber and then floor of maxillary sinus forming another chamber(green)
blue->*When they are smaller maxillary sinus chambers, they are formed by the small dense bones known as nasal septa
*Maxillary sinuses are air cavities that’s why they look dark
!!! DO NOT FORGET!
The nasal cavity although is mostly visible in the anterior radiographs, it still shows in posterior radiographs sometimes.
The nasal cavity runs parallel to the maxillary sinuses from front to back and goes all the way to the nasal pharynx
red->*Right floor of Nasal Cavity
green->*Continuation of the floor of the Nasal cavity back to more posterior teeth and
blue-> joins the wall of the maxillary sinus and makes the shape of an almost inverted Y, so this conjunction is called an inverted Y. Note that in reality we don’t have this conjunction known as the inverted Y, and is just a radiographic figure that is shown only on X- Rays.
red->*Another example for inverted Y
Sometimes inverted Y does not really show,
yellow-> and we see just a small part of the floor of the maxillary sinus.
blue->lateral fossa
*Radiolucent unwell defined area next to the lateral incisor, this area is known as the lateral fossa and is a concavity and the alveolar bones in this area is very very thin and radiolucent in appearance.
red->*Nasal Labial Fold
*We can also see the inverted y and floor of the sinus in those radiographs
*The inverted y is not an anatomic structure, so sometimes those conjunctions do not come together as Y but instead as an X.
red->Floor Of Nasal Cavity
yellow->Wall of maxillary sinus
*Floor Of Nasal Cavity and Wall of maxillary sinus they cross each other and that’s why we see the X and not the Y
Some other times things become more complicated as such:
green->*Anterior Wall of Maxillary Sinus
blue->*Septation of Maxillary Sinus which divided the maxillary sinus in smaller chambers
purple->*Floor of Left nasal cavity
*Lateral Pterygoid plates lie posterior to the maxillary arch
*Maxillary Tuberosity which is the posterior end of the maxillary arch, and posterior to that there’s a big gap which serves as a passage for blood vessels ,and muscle attachment and the Lateral Pterygoid stands just behind that.
*The gap is known as the Hamular Notch
green->Maxillary Tuberosity
red->Hamular Notch
red->*Anterior wall of Maxillary Sinus diffusing with Floor of Nasal Cavity and forming the X.
green-> Floor of Nasal Cavity
blue->*Nasal Labial Fold which is in the form of a diagonal line
red->zygomatic process of the maxilla
green->zygomatic arch
blue->floor of the nasal cavity
*Dense U shaped structure is known as the zygomatic process of the maxilla, and from the zygomatic process the zygomatic arch starts which is the dense line going backwards
*The horizontal line crossing the radiograph, being parallel to the long axis of the radiograph is the floor of the nasal cavity
red->*Zygomatic arch
Zygomatic process = cheekbone?
yellow->*Floor of the maxillary sinus and it crosses the root of the molar
red->*Maxillary Tuberosity
yellow->*Floor of maxillary sinus
green->*Zygomatic process
blue->*The dense part attached to the zygomatic process is the zygomatic arch
*Sometimes depending on the angulation of the X-ray we can’t really see the pathology of the molar due to the conjunction of the zygomatic process in this part of the molar (due to the angulation through which the X-ray is being taken)
*Sometimes the angulation can get extreme so that not only does the zygomatic process and arch cover part of the root of the molar but instead covers more than the whole root of the molar so this radiograph has to be retaken and is considered to be not diagnostic.
*Osseous structure showing distal to the maxillary tuberosity, it’s a hamular process and will very very rarely show.
purple->Maxillary tuberosity
blue->Zygomatic Process
green->Floor of maxillary sinus
red->Hamular Process (they look different from person to person) pointy osseous structure.
Maxillary sinus pneumatization which is the expansion of the maxillary sinus to the crest of the alveolar bone so in these case it occupies the alveolar crest, this means that the maxillary sinus has expanded, this is not pathological but if we want to put an implant there we can’t because of this phenomena sometimes due to tooth extraction and having a thin bone.
Sometimes a structure of the mandible shows on the maxillary arch, and this is the coronoid process of the mandible.
IT”S THE ONLY STRUCTURE from the mandible that could show in the maxilla
Another example of the coronoid process showing on the maxilla.
It’s overlapping on the maxillary structures.
Another example of the coronoid process of the mandible showing on the maxilla and this is due to the fact that the patient opened his mouth really widely.
*Genial Tubercle is an opaque structure that surrounds a small hole, the lingual formaina is the small hole and the dense strcuture around it is the genial tubercle.
red->Genial Tubercle
blue->lingual formaina
Figure.2.
The Mental ridge is the dense wide converging line towards the apex of the mandibular teeth, it is actually our chin.
red->Mental ridge
blue->Nutrient canal
yellow->bone loss visibl
Sometimes a diffuse low-density area is seen and it is known as the mental fossa, the bone is very thin in this area that is why it looks radiolucent. (in the circle)
Nutrient canal are the thin radiolucent lines going from top to bottom and they carry vascular canals and more prominent upon having periodontal disease (in those pics we have severe periodontal disease- we can see it due to the bone loss visible)
The periodontal inflammation shown induces hyperplastic/ hypertrophy of the vascular canals of the gingiva or the crest of the alveolar bones
Figure 2:
Some dense structure we may sometimes see on either side of the mandibular on the premolar or canine region, these structures are known as the mandibular tori (mandibular torus), those masses of bone can be injured when the patient is eating hard food, very benign.
red->Mental foramen
The Mental foramen is a small hole we see between the 2 premolars which searches the exiting point of the inferior alveolar nerve or the mental foramen exits that foramen
*This is the continuous of the mandibular canal; the mandibular canal is the radiolucent structure.
The mandibular canal is in the center of the lingual aspect of the mandibular bone and sometimes makes a sharp turn towards the buccal aspect of the mandibular bone
*Sometimes the mandibular canal shows very clearly and is composed by 2 walls (inferior and superior) and the radiolucent structure in between is the root canal.
root canal->red
(inferior and superior)->yellow
We can see the root canal here as well.
The further back we go the more the root canal is visualized and depicted.
It looks like it is crossing the roots of the tooth whereas in real life it is not, this is just a radiographic projection.
Very often, we can see a very dense line starting posterior to the molar teeth, and this is the external oblique ridge.
red->Mandibular canal
green->Mental Foramina
The submandibular fossa is a depression on the lingual aspect of the mandibular bone where the submandibular salivary gland nests and it is separated by an opaque line that is known as the oblique ridge.
Internal Oblique ridge which is the separation of the submandibular fossa
Very dense visualization of the oblique ridge and made in an upward angulation and the sharp line is the oblique ridge.
Another example of the internal oblique ridge (under it we can see the submandibular…) and we can see the radiolucent area below it and we can see the superior of the mandibular canal.
red->superior of the mandibular canal
green-> internal oblique ridge
Another example of the internal oblique ridge, which separates the submandibular fossa
red->internal oblique ridge
green->submandibular fossa
Example of the ascending oblique ridge
blue-> oblique ridge
We can know which is back and which is front by the visualization of the oblique ridge, upon seeing the walls of the mandibular canal
Right Mandibular Molar radiograph
Sometimes when we use a very extreme upwards angulation we may see the inferior border of the mandible and the oblique ridge.
This extreme angulation will cause the foreshortening which is when the X-Ray is perpendicular to the film but not to the teeth
blue->oblique ridge.
Elongation is when teeth look much much longer than normal, this happens when the film is perpendicular to the teeth but not on the chin?
✓ 2 radiographs showing carious lesions
✓ Very faint dark shadow on the enamel,
growing into the dentin (early carious
lesion)
✓ In the second radiograph we cannot
see the carious lesion in the enamel (just in the dentin) due to the over shadowing of the canine on the incisor
✓ Most important one and one of the hardest to diagnose
✓ Initial presence on the enamel of the tooth, and they will appear just below the interproximal contact (of the 2 teeth)
✓ Because in that area the enamel rods have a converging appearance towards the centre of the enamel surface
✓ So, the carious lesion will have a triangular shape
✓ The moment the caries reaches the dentino-enamel junction it will spread and will look like a flat surface (flat lime) along the dentino-enamel structure
✓ the most common shape is triangular, but do not be surprised if it was not
✓ What ever interrupts the continuity of enamel = suspicion of caries
When caries reaches the dentino-enamel junction and starts advancing into dentin, another triangle is formed
o First triangle is below the contact point between to neighbouring teeth in the enamel o Then caries spread along the dentino-enamel
junction
o And then another triangle is formed into the
dentin
✓ (red arrow), caries into the enamel, then another triangle “caries into dentin”
✓ Also, multiple carious lesions
✓ we can even notice that the caries in dentin is much bigger than the ones in enamel andthat’s simply because enamel is harder
✓ So, when the bacteria reach dentin it spreads faster (rapid intervention needed)
✓ No obvious shape (when caries are too big), so they grow following the path of least resistance
✓ the radiolucency pointed at with the red arrow, are caries growing into the root of the tooth
✓ Very deep caries on the premolar (just a small portion is intact)
✓ Also, on the distal aspect of 44, carious lesion on the enamel and growing into the dentin
o Deep carious lesions will still show even when we have overlapping
✓ Interproximal caries on all maxillary teeth (starting from the lateral incisor)
✓ When the carious lesions are on the interproximal area of the anterior teeth, the enamel rods are oriented parallel one to another
✓ So, caries won’t look like triangles, but they will look ovoid/rectangular shape
✓ On of the pros of digital imaging is image magnification
✓ Another example of extensive radiolucency on the incisors
✓ These might not be necessarily caries
o Some older composite was radiolucent, and will look like caries on radiographs
✓ The only radiolucent carry here is on tooth 21
(red arrow)
o When preparing a cavity with our
handpieces we make a nice shape on the cavity that will be filled (square shape)
o Caries make an ovoid shape and move in the path of least resistance (plus it undermines enamel, which no dentist does)
✓ An occlusal carry is when it reaches the DEJ, it’s impossible to see if it was only on enamel
✓ Occlusal carries on tooth #46, crescent shaped radiolucency but we do not see it on enamel because the thickness of enamel is so big in that area that it’s impossible to see but when it breaks in the DEJ we can see it
✓ Another carries on tooth #16
o This tooth can’t develop interproximal carries (distally) because there is no adjacent tooth next to it
o So, the radiolucency is an occlusal carry
o It’s only shown when it reaches the DEJ
✓ It is important to have the right radiograph to assess the carries
o Bitewing best for interproximal carries
o Also, good to assess occlusal carries (if they broke into the DEJ)
✓ In here the bitewing radiograph shows better the radiolucency (#26) than the periapical one
✓ We need to check multiple radiographs views to fully assess the caries and no neglection of the clinical examination
✓ All carries when big will be shown
✓ The mineralization advance faster than the appearance of radiolucency on the radiographs
o Ex. #47 it may already be advanced to the pulp horns even if it does not show
o Also, we find large interproximal carries (#46, 16, 15)
This is how a tooth will look when an entire tooth surface has been gone
o This transparency means that a whole side (lingual or buccal) is gone (destroyed)
✓ This large radiolucency, is overlapping the pulp chamber (but didn’t invade the pulp chamber)
✓ It’s a lesion that is grown either on the buccal or lingual surface
✓ Clinical correlation will tell if it’s on the buccal or lingual surface
✓ Another buccal or lingual carries (#46), overlapping the distal pulp horn
✓ Plus, clinical assessment is needed
✓ Palatal or labial carries will show must easier on the front teeth
✓ They will grow along the gingival junction on the front teeth (reversed U shape or crescent)
✓ They may coincide with different caries
✓ Classical appearance of root caries
✓ Growing big under the crest of the
alveolar bone
✓ Here, it is causes by this bad, very
poorly contoured restoration
✓ Food will be packed, and then
caries are easy to be developed there
✓ Other examples in teeth #48 and #47
✓ It’s going to grow faster, and deeper cause cementum is softer than dentin
✓ As we can see on tooth #16, there is a carious lesion below the amalgam restoration (interproximal)
✓ Special attention to amalgam restorations
✓ The restoration on tooth #46 is surrounded by a low-density zone➔ recurrent caries
✓ Also, interproximal caries on the mesial aspect of that tooth and distally on tooth #45
✓ Facial carries on the canine (#13) “crescent shape” and on the premolar (#14)
✓ Additional small interproximal carries on #14, 15,44
✓ Another recurrent caries under the amalgam restoration on the distal aspect of the 1st premolar #24
✓ Also, on tooth #34, recurrent caries under the amalgam restoration
✓ And on tooth #37
✓ When we see radiolucency below a
restoration, we should be suspicious of recurrent caries
✓ The more the extensive the restoration is the higher the chances of having recurrent caries
✓ Tooth #46 (the extensive restoration on the neighbouring tooth caused the caries on #46) (it was a food packing area, so harder to clean and that will lead to plaque accumulation)
✓ Also, on #16 a small radiolucency is seen on that poorly constructed restoration
✓ On tooth #36, there is occlusal carries which has grown into the dentin
✓ However, there is dense opaque zone of dentin comparing it to the surrounding dentin, and that what characterise it as arrested caries
Arrested Caries:
Arrested Caries (caries that stopped, and the tooth started to produce reparative dentin. That reparative dentin forms a dense border between the carious lesion and the tooth pulp)
o Occlusal lesions
o Thin radiopaque band
✓ Another example of arrested caries, very bright (dense) zone of dentin below an extensive occlusal caries (tooth #37)
✓ Regular occlusal carry on #27 and interproximal carries distally
✓ Cervical burnout is one of the effects that we may confuse healthy tissues with caries
✓ As seen (on the red arrows), on the cervical regions of teeth, just at the border between the crest of the alveolar bone and the tooth just at the level of the CEJ we have some dark (radiolucent) areas
✓ This dark zone is known as cervical burnout
✓ (most on cylindrical teeth like premolars and canines, sometimes molars)
✓ It an optical effect were the tooth appear more radiolucent simply because the thickness of the tooth structure there is thinner than core of the tooth
✓
So, X-rays there are attenuated less,
and the X-rays will pass a darker
shadow than the neighbouring tooth
structure
✓ The Mach band effect, is an optical effect which appears when we have multiple alternating dark and white areas
✓ Example: looking for a couple of seconds on the black squares, we will start making grey squares in the middle of the white crosses
✓ This will also appear on radiographs when we have alternating white and dark areas
✓ Especially in premolars, some areas will look like radiolucency especially below the cusps (like red arrows)
✓ Those are Mach band effect not caries
✓ It’s an optical effect (we can’t avoid it)
✓ We need to learn how to over come technique errors (meaning view different radiographs of a specific site)
✓ As said before, B/W radiographs are best for interproximal carries and recurrent caries
✓ We can see the difference between the 1st and the 2nd radiograph
✓ It looks good in the 1st , but when we did the B/W radiograph we can see a tremendous recurrent carious lesion on the distal part of the molar (#26)
✓ So, we have to look at both radiographs to assess possible presence recurrent carries (don’t rely on one radiograph only
How efficient are our diagnostic tools? (for caries detection)
o Half proximal lesions go undetected with explorers
o X-rays are 60% sensitive in the diagnosis of proximal caries (the show
only about 60%) (so we must use all our diagnostic tools and combine them)
We have to do
o Very thorough clinical examination
o Flawless radiographic technique
o Experience in radiographic interpretation
What is the normal appearance of the crestal bone?
What is the normal appearance of the crestal bone?
✓ The normal appearance is as seen on the red arrow, with very clear cortical outline. Also, in the dental areas (between teeth) being as a continuum of the lamina dura
✓ What we see is that the crestal bone is a continuum of the lamina dura of the neighbouring teeth (continuum of the cortical bone)
✓ The moment that this continuum is lost, the moment we see the crestal bone lost (it is where the periodontal disease starts) then we instantly are suspicion of early periodontal changes
✓ Alveolar ridge lies 1-1.5mm from CEJ of adjacent teeth
✓ Green = CEJ ‘enamel of the crown meets the cementum of the root’
✓ Pink = alveolar crest
✓ If we measure the distance of
the crest of the alveolar bone to the CEJ then this should be 1 to 1.5mm on a healthy individual
✓ If this distance is increased ➔ early periodontal changes (early bone loss)
✓ Same goes for anterior teeth, however on anterior teeth the crest of the alveolar bone is very pointy
✓ Keep in mind, our radiographs are sometimes are at an angle so the CEJ is also at an angle
✓ So, the CEJ of both adjacent teeth is not horizontal but at an angle (in a slope/diagonally)
✓ So, there is some flexibility into the assessment of the height alveolar crest to the CEJ, simply because our radiographs are not always perfectly done
✓ And if they are not perfectly done that means we have to draw these lines at an angle (example green and pink lines)
✓ Fuzzy appearance of the crestal cortex
✓ No sign of the cortical outline
✓ Loss of the cortication of the
alveolar ridge
✓ So early sign of periodontal changes
(bone loss)
✓ The assessment is always done on B/W radiographs
✓ Loss of crestal cortex
✓ Another example of early bone changes
✓ It may not necessarily occur in all teeth
✓ It may occur in some sets of teeth, keeping in mind that periodontal disease is not always generalized (affect specific teeth)
✓ The key feature is the distance between the crest and the CEJ has increased (more than 1.5mm) + loss of crestal cortex (fuzzy appearance of the alveolar crest)
Teeth that are affected more by periodontal disease are Max. Molars, Man. Molars, and Man.incisors
✓ Early periodontal changes
✓ Considerable amount of bone loss (at least 4mm)
✓ As we said before on the mandibular incisor, we not only loss the crestal cortex but it also becomes blunt (flat)
✓ Fuzzy appearance of the cortex
✓ The distance between the neighbouring CEJ to the crest has increased
✓ Flat crestal cortex
✓ In here, we can see that things are getting worse (considerable loss of bone), and that bone loss starts to form osseous defects
✓ Also, it has some angulation and this what we call vertical or horizontal osseous defects
✓ The bone loss is more on the distal aspect of the central incisor (#21) vs the mesial aspect of #22, that why the crest takes on an angular slop (the osseous defect is deeper on the distal and shallower on the mesial)
✓ This defect is known as vertical osseous defect (when the crest of the alveolar bone is not parallel to the CEJ)
✓ When the bone loss is roughly parallel to the CEJ➔horizontal osseous defect
✓ Another example of horizontal osseous defect
✓ In here it is between early and moderate bone loss
✓ Moderate bone loss (5mm)
✓ The more advanced the osseous
defects are, then we will see that the shape of the crestal cortex starts to change (ex. The mandibular bone)
✓ We can clearly see the wavy appearance of the crestal cortex and almost a double margin appearance
✓ This double margin reflects the buccal and lingual cortices of the alveolar bone (they are at different heights)
✓ There is also a gap in between the 2 cortices and that what gives it the wavy appearance
✓ Another example of horizontal bone loss
✓ The crestal cortex is horizontal to the CEJ➔horizontal osseous defect➔pure horizontal bone loss
✓ Vertical bone loss (no parallelism)
✓ Another way to see it is, when the defect is deeper in one side of the tooth in comparison to the other side (can be also classified as vertical bone loss)
✓ Classical example of severe vertical osseous defect
✓ The crest is not parallel to the CEJ
✓ Examples of horizontal osseous defect
✓ Again, when we see different cortical outlines on the crest ➔the bone loss is advancing differently on the buccal and lingual cortex and the bone have a gap (a space in between)
✓ Inconsistent bony margins
✓ We can tell because there is
different shade (of grey) in between the 2 margins (on is buccal and the other is lingual)
✓ We cannot tell which is buccal and which is lingual from one radiograph
✓ Again, when we have inconsistent margin➔the periodontal disease is advancing at different rate (in the inner aspect vs the outer aspect of the alveolar bone)
✓ When we see this localised bone loss with 2 different margins between the crestal cortex➔this may indicate interproximal crater, meaning that since the bone loss is advancing differently on the crestal cortex on the lingual vs the buccal, there is a gap in- between called the crater
✓ The bony margin may be higher but that grey in between indicates bone loss in between the 2 bony margins
✓ We can even identify these craters clinically (no need to look on the radiographs)
✓ Every time we see this grey space in between one crest and the other crest➔always be suspicious of interproximal crater
✓ Some host factors associated with bone loss are bad restorations, dental caries
✓ The alveolar bone may show little bone loss (on the mesial of the molar ‘red arrow’) and a tremendous bone defect on the distal
✓ So, the etiologic factor here is the bad restoration
✓ Vertical bone defect (red arrow), severe bone loss (more than 50%) and it is local
✓ Looking at the molar (#36), there is furcation involvement➔bone loss between the roots. And on the mesial aspect of this tooth we see 2 different levels of crestal cortex➔ the space in between is an interproximal crater
✓ We see here another tremendous vertical bone loss (red arrow) and development of a huge gap
✓ When we see this big osseous defect, they will go at an angle all the way to the apex, plus there is some clinical symptoms to it (the patient is in pain, they might be oedema in this region, very easy bleeding)
✓ This is classified as a periodontal abscess (big osseous defect that almost reach the apex of the tooth and leaves wide spaces between the crest and the tooth)
✓ This big defect area was diagnosed as a periodontal abscess
✓ The defect goes all the way towards the aspect
✓ How to make the distinction, between this or the standard moderate bone loss. Simply, the periodontal abscess is local, it affects one tooth only or maybe 2 teeth maximum
✓ Whereas moderate or severe periodontal bone loss is identified across the dentition
✓ This osseous defect is also symptomatic (the patient is in pain)
✓ We can cause severe bleeding just by probing in that area
✓ The periodontal abscess can even involve the periapical region of the tooth and can easily become and endo- perio defect (leading to tooth necrosis)
✓ Tremendous bone loss around the central incisor (#21)
✓ It is local (osseous defect)
✓ This tooth most likely has a perio-
endo defect
✓ Another thing that can tell us that
there is a periodontal abscess is that the incisal edge of the affected tooth looks over erupted compared to the normal incisor
✓ Another example of periodontal abscess (red arrow), on both side of the tooth
✓ PDL space widened ➔ indicates mobility
✓ (uniformly widened➔the tooth is moving
✓ Furcation involvement (big dark triangle in between the roots of the teeth)
✓ As the bone loss advanced then the multirooted teeth will be exposed (furcation)
✓ Can be diagnosed clinically
✓ Again, the B/W radiograph is the best to diagnose periodontal bone loss
✓ We have minimal furcation involvement on the mandibular molars
✓ The B/W is advantageous cause of the angulation of the X-ray beam (especially for the maxillary bone)
✓ The extreme angulation used on the periapical radiograph (will affect the visualization of the furcation
✓ Furcation involvement on a deeply decayed tooth (#46)
✓ Caries around the root
✓ Moderate to severe bone loss
✓ Interesting way to see a furcation involvement on the maxillary right molar
✓ Another example of periodontal abscess (severe in that case)
✓ The tooth here looks like it is floating
✓ The tooth is mobile
✓ (in here we might have a co-
existence of a periapical pathology and periodontal pathology)
✓ Large periodontal abscess
✓ The tooth suffered tremendous
bone loss, and the osseous defect has surrounded the whole root of the tooth
Periapical Inflammatory Lesions
Acute Vs. Chronic Lesions:
Apical Rarefying Osteitis:
Rarefying means lower in density / dissolving
Osteitis means inflammation of the bone
Apical Rarefying Osteitis means dissolving of the bone in the apical region.
red->Lesion started from the crest of the alveolar bone and gradually advanced to
blue-> the apex and we can also see PDL widening around the roots, also notice the lesio around the furcation of the roots.
Apical Rarefying Osteitis
red->We can see the rarefying lesion and the radiolucencies green-> and then we have denser bone around it, this is the condensing osteitis status, which means that this lesion has been there for a while and now due to the chronic stimuli the bone around the rarefying lesion is becoming denser and denser.
Osteomyelitis
Alternating appearance of the bone where we have lower density and higher density which is the classical appearance of osteomyelitis, clinically we might see bone which is necrotic, or we will see loose pieces of bone which are sequestrations (sequestra bone)
Interrelationship of possible results of Periapical Inflammation:
Apical Rarefying Osteitis & Sclerosing Osteitis
Apical Rarefying Osteitis & Sclerosing Osteitis
A post was used to restore the tooth, but it wasn;t well placed thus caused in a split structure, we can see apical rarefying osteitis and condensing osteitis on the mesial root of the tooth (green)
Apical Rarefying Osteitis
Halo Effect:
red->Apical inflammatory lesion, we can see a radiolucency, and we can see
green-> a thick corticated border around the lesion which is the floor of the maxillary sinus that has displaced upwards as the lesion was growing, and this is known as the Halo Effect.
Root Resorption due to inflammatory lesions for long times
Halo Effect & Mucositis
green->Halo Effect
red->Mucostits (Mucosa on floor of maxillary sinus / thickening of maxillary sinus)
Mucositis
Internal Resorption
Internal Resorption
Internal Resorption
Periapical Cemental Dysplasia
Periapical Cemental Dysplasia
Idiopathic Osteosclerosis
Idiopathic Osteosclerosis
pericoronitis
osteomylitis
garre’s osteitis
- What Kind of Radiograph is it?
- What Kind of Restorations b/w 14 and 16?
- What is the thin opaque line crossing the apex of maxillary molars?
- What Kind of Radiograph is it? Periapical Right MAxillary Premolars Radiograph
- What Kind of Restorations b/w 14 and 16: A fixed prosthesis of porcelain fused to metal bridge
- What is the thin opaque line crossing the apex of maxillary molars? (Red arrow) Floor of maxillary sinus
ONJ
What Can we see on tooth 17?
- Apical rarefying osteitis or peripapical inflammation.
- Well defined periapical granuloma
What kind of periapical radiograph is this?
condition?
red->Apical Rarefying osteitis and surrounding by chronic sclerotic osteitis
green->Gutta Percha
What kind of periapical radiograph is this?
Mandibular left Canine PA radiograph
Rarefyeing osteitis and we have a dense zone separating the healthy zone and it’s around the rarefying osteitis→Granuloma bcz it’s a well defines osteitis
Well defined periapical granuloma bcz it’s well defined
And we can see sclerotic bone around
This lesion is not a well defined lesion it’s a periapical abscess / inflammatory lesion
green->Amalgam Restoration
red->This lesion is not a well defined lesion it’s a periapical abscess / inflammatory lesion
What kind of bone defect we have between 13 and 14?
What kind of bone defect we have between 13 and 14?
Vertical Bone Loss
Tooth 14 has an apical radiolucency / apical rarefying osteitis
We have radiolucent mandibular bone almost rarefying osteitis.
We also have a cyst above tooth 21 -22
Periapical Granuloma
Apical rarefying lesion
red->we have recurrent caries (Secondary caries)
purple->Horizontal bone loss
green->Apical rarefying osteitis under it we have a dense bone which is sclerotic bone (sclerotic osteitis)
Teeth 11 and 21 have composite restorations and on tooth 21 we have secondary caries
Apical rarefyinf osteitis as well
Halo Effect
- We can see many apical rarefying osteitis
- And we have multiple recurrent caries
- Chronic because we have sclerotic dense bone (it doesn’t happen over night)
Rarefying osteitis surrounded by a dense zone of cortical bone, it’s a periapical granuloma
Halo effect on floor of maxillary sinus
What kind of pathology do we see on tooth 26?
What kind of pathology do we see on tooth 26.
- Left bitewing radiograph of premolars.
- The pathologies we see are:
- The mesial interproximal caries lesion getting in the dentin and distally as well deeper in the dentin
What is the diagnosis for tooth 47?
What is the diagnosis for tooth 47?
- Distal root resorption, and we have apical rarefying lesions
- And on 46 we have on both tooth rarefying osteitis
- We also have condesning sclerotic bone
- Lateral inflammatory lesions, sometimes if the infection is associated with the lateral canal
- When we see lateral lesions this means we have accessory canals that may open in the specfic area
- So basically next to the epicenter of the lesion we might have an accessory canal showing.
- We don’t see them bcz they are veryyy small
- Periapial inflammatory lesion
- Red arrow-> the inflammatory lesion caused a halo effect
We have 2 lesions on the mandible:
- red->PDL widening and apical rarefying osteitis around the roots of the molar
- green->Well defined radioluent lesion if it was small we could call it periapical granuloma but since it’s a big we will call it a radicular cyst or periapical cyst
Which is the orientation of this radiograph?
- Maxillary right molar
What is the orientation of this radiograph?
- Maxillary left premolars
- Left premolar bitewing radiograph
What is the orientation of this radiograph?
- Mandibular left canine periapical radiograph
What is the orientation of this radiograph?
- Rt premolar bitewing radiograph
What is the orientation of this radiograph?
- Periapical left maxillary canine radiograph
What is the orientation of this radiograph?
- Right premolar mandibular periapical radiograph
What is the orientation of this radiograph?
- Maxillary left premolar periapical radiograph
What is the orientation of this radiograph?
- Mandibular left premolar periapical
What is the orientation of this radiograph?
- Mandibular incisor periapical radiograph
What is the orientation of this radiograph?
- Mandibular left molar pa
What does the arrow indicate?
- Root caries
What do the arrows indicate?
- Green arrow=cervical burnout
- red=root caries
What do the arrows indicate?
- Cervical burnout
What do the arrows indicate?
- Distal #35 small enamel caries
- # 36 caries that just got into DEJ
What does the arrow indicate?
Deep carious lesion into dentin
Describe the image.
- Periapical maxillary right premolar
- Fixed prosthesis PFM bridge from #14 to #16
- Periapical inflammatory lesion on #14 (the closer the better defined the lesion
- Appearance of surrounding bone it isn’t alteredno condensing osteitis or reactive sclerosis
Describe the image.
17 apical rarefying osteitis *Radiolucency=rarefying osteitis
Describe the image.
- Apical rarefying osteitis #33
- Guta percha on #33
- Mandibular left canine periapical
Describe the image.
- Rarefying osteitis on #36
Describe the image.
- Dense bone around it is sclerotic or condensing osteitis
- Can be apical granuloma->radiolucent part
- Rarefying osteitis
- The better defined the most likely to call it granuloma
- The less defined the most likely to be a cyst
Describe the image
Describe the image.
- Looks like an expansion of lamina dura
- Well defined lesion=> periapical granuloma or periapical inflammatory lesion or periapical abscess
- Amalgam restoration #26
Describe the image.
- Vertical bone loss between #13 and #14
Describe the image.
- Radiolucency at the apex
Describe the image.
- Radiolucent bone on the mandible
- Rarefying osteitis on the mandibular bone
- Trabeculae are wide and horizontically oriented on the mandible
- Cyst above #21 #22
Describe the image.
Cyct
Describe the image.
Periapical granuloma
Describe the image.
well defined border
- Rarefying osteitis
Little bit of halo on maxillary sinus
Describe the image.
- Recurrent carries around the restoration of the tooth
- rarefying osteitis condensing osteitis and horizontal bone loss
Describe the image.
- composite restorations on #11 and #12
- secondary caries on 21
- apical rarefying osteitis around 21 22 and 12
- dense bone
Describe the image.
- halo effect
Describe the image.
- surrounded by chronic sclerotic osteitis
- dense bone takes time and that’s why its chronic-in order to develop sclerotic and dense bone needs time
Describe the image.
- periapical granuloma
- rarefying osteitis surrounded by dense zone of periapical bone
- periapical granuloma
Describe the image.
- halo effect in the floor of maxillary sinus around the mesiobuccal root of the molar
- inflammatory lesion around palatal root of molar
- halo is associated only with floor of maxillary sinus
Describe the image.
- mesial interproximal carious lesion on #26
- pulp chamber-opaque because some pulpal floor of the molar is really dense
- big roots originating from a common trunk
