Crown lengthening Flashcards
Indications for Crown Lengthening
Functional
(4)
- Subgingival restorative margins
- Tooth fracture
- Endodontic perforations
- Cervical root resorption
Indications for Crown Lengthening
Esthetic
(3)
- Excessive gingival display
- Gingival overgrowth (meds)
- Altered passive eruption
Components of
Supracrestal Attached
Tissue (formerly Biologic
Width)
Connective Tissue Attachment
(2)
Junctional Epithelium
(2)
Added together =
- Most consistent dimension
- avg., 1.07 mm
- Most variable dimension
- avg., 0.97 mm
2.04 mm
Crown Lengthening Indications
* To allow for —
* Increasing crown length for —
* Restoration of tooth in harmony with —
* Esthetics via alteration of the —
restoration of tooth (Caries removal, clamp placement)
retention of restoration (adequate ferrule)
supracrestal attached tissue (biologic width)
gingival labial profile
What is Ferrule?
- It is the vertical axial wall that
surrounds the tooth
Ferrule
* Desired every time a crown is
fabricated to help —
* Need at least – mm of ferrule
(natural tooth structure)
circumferentially, beyond the
core
resist
fracture &/or crown
displacement
2
Considerations and Limitations
* Is tooth actually restorable?
* May need — to determine
* PLEASE ensure …
O&R
caries free before crown lengthening consult as may not be restorable
Considerations and Limitations
Is tooth strategically important?
(2)
- Opposing tooth
- Position in arch
Considerations and Limitations
Prognosis
(5)
- Amount of tooth remaining in supporting bone
- Furcations
- Mobility
- Esthetic concerns
- Thick or Thin Phenotype (or needs conversion?)
**At end of
procedure
place well
fitting
temporary
back on
tooth to
prevent
–
tooth
migration
Final Restoration placement
* Variations between (time), but NOT —
* Bragger and Sonick - 6 weeks
* Bragger, Lanning - 3-6 months
* Lee - 3-6 months
* Pontoriero - 6 months
6 weeks and 6 months
sooner
If in doubt, provisionalize (well) and hold for — before final
restoration
3-6 months
IDEAL scenario
In Health
* CEJ should be approximately – mm from osseous crest
* Gingival margin should be – mm coronal to the CEJ (i.e.,
covering anatomic crown)
2
0.5-2.0
Active eruption
(3)
- As tooth breaks through gingiva
- Erupts until it meets its antagonist and occludes, then eruption
ceases/slows - Eruption POTENTIAL continues throughout life (think supraeruption
of tooth that has no opposing tooth)
Passive eruption (Ainamo and Loe 1966)
* Apical shift of Dentinogingival junction
(2)
- Occurs during and after active eruption
- Tooth does not move, gingiva does (apically)
Passive eruption (Ainamo and Loe 1966)
Stages
(4)
- Junctional epithelium (JE) rests on enamel surface
- JE rests on enamel and cemental surface apical to CEJ
- Epithelial attachment rests on cementum
- Epithelial attachment migrates apically
Normally concludes when sulcus base is at level of CEJ placing the gingival
margin – mm coronal to the CEJ
1-2
Altered Passive Eruption
* When …
* Frequency is about –% in adult population
eruption does not progress past Stage 1 or 2 it is termed Altered
Passive Eruption.
12
Altered Eruption (diagnosis)
includes Excessive Gingival Display aka ‘the Gummy Smile’
Altered Active
(2)
- Morphologic variant where CEJ
is less than 2mm from osseous
crest - Can be exacerbated by
orthodontic brackets
Altered Eruption (diagnosis)
includes Excessive Gingival Display aka ‘the Gummy Smile’
Altered Passive
(2)
- Morphological variant where
gingiva is more than 2mm
coronal to CEJ - Can be exacerbated by
inflammation, medications
Skipped
Classification and Treatment
Type 1 A: Adequate KG; MGJ apical to osseous crest; adequate
distance from CEJ to bone crest
Gingivectomy
Skipped
Classification and Treatment
Type 1 B: Adequate KG; MGJ apical to osseous crest BUT
osseous crest at CEJ
Gingival scallop with Internal bevel then ostectomy
with unchanged flap position
Skipped
Classification and Treatment
Type II A: Inadequate KG; MGJ at or coronal to osseous crest
Apically Positioned flap (don’t want to remove any KG)
Skipped
Classification and Treatment
Type II B: Inadequate KG; MGJ at or coronal to osseous crest
AND osseous crest at CEJ
Apically Positioned Flap with Ostectomy
What are the components of an appealing
smile? (What is the ‘perfect’ smile??)
(5)
- Teeth
- Gingival scaffold
- Lip framework
- Skeletal profile
- The eyes
- Teeth
- Size, shape and position
- Gingival scaffold
- Health and contour
- Lip framework
- Shape, length and mobility
- Skeletal profile
- Maxillary excess (may require oral surgery intervention)
Clinically
* Show —% of crowns
and interproximal gingiva
* Symmetrical display and
harmony between the
(2)
* Lower lip parallel to the
…
75%-100
maxillary gingival line and
the upper lip
incisal edges of maxillary
teeth and in close
approximation
Smile Line
- Position of the upper lip relative to the maxillary incisors and gingiva
during a natural full smile
Normal Anterior Tooth Length*
Tooth Normal variation (mm) Minimum ‘normal’ (mm)
Central
Lateral
Canine
11-13 10
10 9
11-13 10
Preferred anatomical crown width to height ratio is –%
* Acceptable range –%
* Regardless of (2)
78
66%-80
race or gender
- Central Incisor Width—% wider than the lateral incisor
- Lateral incisor Width- –% wider than the mesial portion of the canine
60
60
If assign a value of – to lateral incisor, then in anterior view
* Central incisor would be – x width of lateral incisor
* Canine would be – x width of lateral incisor
1.0
1.6
0.6
Esthetic Smile
Gingival Zenith
* Centrals- — mm distal to midline
* Laterals- — mm distal to midline
* Canines- centered –
1
0.3
M-D
Gingival Margin
* Central and canine ON —
* Lateral – mm CORONAL to central and
canine
SAME LINE
0.5
To help determine
classification and
treatment
* Perform detailed —
* Look at amount and location of —
* Evaluate location of supporting bone using
(2)
* Understand where the — is located
* Understand the Clinical vs Anatomic — of
the teeth (radiographs)
Smile Analysis (Esthetic
Analysis Form available on AxiUm)
keratinized
tissue
* radiographs &/or
* bone sounding (under LA)
CEJ
size
To determine treatment
* Diagnostic radiographs
(3)
- Anatomic vs. clinical crowns
- Location of CEJ
- Location of osseous crest
To determine treatment
* Assess probing depths
(2)
- Location of CEJ
- Location of osseous crest
To determine treatment
* Keratinized tissue
* Assess quantity
(2)
- Thick, normal or thin
- Narrow or wide
Skipped
Smile Analysis for DDS
(3)
- Refer to Operative III Course this semester specifically Sept 9th lecture
(Dr. Seabaugh) - Additional Info-Lecture on Elements of Smile Design (Dr. Leal in
Advanced Pros) - Esthetic Analysis Form and Instructions on AxiUm (updated Sept 2022
)
