Crown lengthening is a surgical procedure used to expose more of the clinical crown for esthetic or restorative purposes. There are several techniques for crown lengthening including gingivectomy, flap surgery, and lasers. Gingivectomy involves removing gum tissue while flap surgery involves raising a flap and removing underlying bone. The biologic width must be considered to avoid compromising tissue health. Crown lengthening can allow for improved restoration margins or smile appearance.

1. CROWN
LENGTHENING
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2. CONTENT
• INTRODUCTION
• ALTERED PASSIVE
ERUPTION
• BIOLOGIC WIDTH
• CLASSIFICATION OF
TECHNIQUE
• GINGIVECTOMY
• FLAP SURGERY
• LASERS
• EXTRUDED TOOTH
ERUPTION
• SUMMARY
• CONCLUSION
• REFERENCES
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3. INTRODUCTION
• Clinical crown - tooth that extends occlusally or incisally
from gingiva (AAP 1992).
• Anatomic crown – CEJ – occlusal or incisal surface.
• Normal position - gingival margin -approximately 0.5 to
2.0 mm coronal to the CEJ. (Loe 1968).
• Purpose – esthetic or restorative.
• Crown lengthening – D. W. COHEN 1962
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4. ALTERED PASSIVE ERUPTION
• Active and passive eruption.
• Clinical condition that occurs following tooth eruption
wherein the free gingival margin comes to rest “at” or
“coronal to” the cervical bulge of the tooth.
Goldman & Cohen, 1968
• Leads to “square and squatty” appearing clinical crowns.
• Un-esthetic clinical appearances - maxillary anterior
sextant.
• Referred to as the “gummy smile”- Evian et al, 1993
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5. Flap with
osseous
surgery
COSLET et al 1977
Altered
active
eruption
–
Amster
dam
1991
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6. BIOLOGIC WIDTH
• Sicher 1959
• Dimensional width of the dentogingival junction – (J.E
and underlying C.T)
• Restorative margins within biologic width - gingival
inflammation, clinical attachment loss, and bone loss.
• Two conAcepts:
1. Gargiulo et al 1961 – facial surface – 3mm
2. Kois 1994 and Spear 1999 – interproximal surface –
4.5 – 5.5mm.
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7. 7

8. Anatomic factors in determining facial and interproximal
biologic width difference
Gingival Difference
Tissue – bone inter relationship – 2mm greater unsupported ht i/p
Bone Ht Diff – 1mm more i/p
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9. 9

10. CLASSIFICATION OF CROWN-
LENGTHENING PROCEDURES
• Gingival reduction only
1. Gingivectomy
2. Flap surgery
• Mucoperiosteal flap with ostectomy
Apically positioned flap surgery with ostectomy
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12. GINGIVECTOMY
External bevel gingivectomy
• Adequate attached gingiva and no
bone involvement- external bevel
gingivectomy – increasing crown
length.
Internal bevel gingivectomy
• Absence of a sufficient zone of
attached gingiva and no bone
involvement- exposure of
additional coronal tooth structure
with internal bevel gingivectomy.
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13. POCKET MARKERS
GINGIVECTOMY KNIVES
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14. MARK THE POCKETS.
RESECT THE GINGIVA
Discontinuous Incisions Continuous Incisions
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15. Remove the marginal & interdental gingiva.
Instrument is placed deep in contact with tooth & moved
coronally with a slow, firm motion.
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16. ELECTROSURGERY- DEVICE & TIPS
ELECTROSURGERY UNIT.
TIPS FOR ELECTROSURGERY.
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17. GINGIVECTOMY BY ELECTROSURGERY
ADVANTAGES:
Permits adequate contouring of tissue.
Better control of hemorrhage.
DISADVANTAGES:
Cannot be used in patients not compatible or poorly shielded pacemaker
Causes an unpleasant odor.
If it touches bone, irreparable damage can occur.
Heat generated can cause tissue damage if not used properly.
If electrode touches cementum, produces areas of cementum burn.
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18. FLAP SURGERY
• Used to expose sound tooth structure.
• At least 4 mm of sound tooth structure must be
exposed coronally to cover 2-3 mm of the root
(Pontoriero & Carnevale 2001)
• Thereby leaving only 1-2mm of supragingivally
located sound tooth structure – ferrule.
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19. FLAP SURGERY WITH OSTEOTOMY
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20. APICALLY POSITIONED FLAP WITH
BONE RECOUNTORING
Preoperative Determination
• “Bone sound” –probing under anesthesia
to the bone level and subtracting the
sulcus depth from the resulting
measurement - alveolar crest should be
at least 2 mm apical to the CEJ
• Evaluate radiographs
• If required, flap and osteoplasty /
ostectomy to a level of 2 – 3 mm apical
to the CEJ
EP Allen, 1993
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21. Insufficient clinical crown length
Prior to Flap Surgery
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22. Full thickness labial and lingual flaps
Bone recontoured Lingual side- minimal osteoplasty
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23. Flaps positioned apically
Crown preparations Final restorations
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24. Before
After
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25. CROWN LENGTHENING WITH
LASERS
• Er Cr: YSGG LASER
• Soft tissue and hard tissue ablation
• Two methods
• Open – flap
• Closed – gingivectomy – minor zenith correction
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26. OPEN TECHNIQUE
Alveolar crest correction - 9-mm or 14-
mm 600-μm tip.
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27. THE CLOSED TECHNIQUE
• For minor, localized biologic width and/or aesthetic
gingival zenith corrections
Soft tissue resected - 400-μm tapered tip on facial areas or
a 600-μm tip in proximal areas
9-mm 600-μm tip - holding the tip
adjacent to the tooth and "walking"
across the affected area using a
"sewing machine" (ie, up and down)
movement to a 3-mm depth – bone
resection.
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28. Laser can reposition the alveolar
crest through the gingival sulcus in a
minimally invasive, controlled
fashion.
After establishing the corrected crestal level, the
bone is "smoothed" by setting the laser at 50
pulses per second and moving the tip in a
horizontal direction over the crestal bone.
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29. FORCED TOOTH ERUPTION
• Moderate eruptive forces are used- entire attachment
apparatus move in unison with the tooth.
• Tooth extruded distance ≥ tooth exposed in the
subsequent surgical treatment.
• Tooth in intended position (stabilized)- a full thickness
flap bone recontouring.
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30. Indication
• Sites - removal of attachment and bone form adjacent
teeth avoided.
• As means of reducing pocket depth at sites with angular
bony defects.
Contraindication:
• requires the use of fixed orthodontic appliances – so
patients with few teeth remaining.
Technique:
• Orthodontic brackets are bonded to tooth and to adjacent
teeth and are combined with an arch wire.
• A power elastic is tied form the bracket to the arch wire (or
the bar), which pulls to tooth coronally.
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31. CONCLUSION
• Crown-lengthening surgery can be a viable option for
facilitating restorative therapy or improving esthetic
appearance.
• When planning a crown-lengthening procedure,
evaluate the patient’s complete periodontal condition
and disclose all possible treatment options to the
patient.
• In cases involving the possibility of a negative esthetic
outcome, compromise to the support of the dentition
involved in the surgical procedure or both, extraction
and implant therapy or conventional prosthetic therapy
may be a more compelling solution.
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32. REFERENCES
• Takei, HH; Azzi, RR; Han, TJ: Preparation of the
Periodontium for Restorative Dentistry. In Newman, MG;
Takei, HH; Carranza, FA; editors: Carranza’s Clinical
Periodontology, 9th Edition. Philadelphia: W.B. Saunders
Company, 2002. page 945.
• Gargiulo, AW, et al. Dimensions and relations of the
dentogingival junction in humans. J Perio 1961;32:261–
267.
• Nevins, M; Skurow, HM. The intracrevicular restorative
margin, the biologic width, and the maintenance of the
gingival margin. Int J Perio Rest D 1984;3:31–49.
• Brägger, U.; et al. Surgical crown lengthening of the
clinical crown. J Clin Perio 1992;19:58–63.
• Padbury Jr, A, et al. Interactions between the gingiva
and the margin of restorations. J Clin
Perio 2003;30:379–385.
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33. • Galen WW, Mueller KI: Restoration of the Endodontically
Treated Tooth. In Cohen, S. Burns, RC, editors: Pathways of
the Pulp, 8th Edition. St. Louis: Mosby, Inc. 2002. page 784.
• Barkhodar RA, Radke R, Abbasi J: Effect of metal collars on
resistance of endodontically treated teeth to root fracture. J
Prosthet Dent 61:676, 1989.
• Fixed prosthodontic lecture series notes, Dr. Louis DiPede,
New Jersey Dental School, 2004.
• Stankiewicz NR, Wilson PR. The ferrule effect: a literature
review. Int Endod J, 35:575–581, 2002.
• Galen WW, Mueller KI: Restoration of the Endodontically
Treated Tooth. In Cohen, S. Burns, RC, editors: Pathways of
the Pulp, 8th Edition. St. Louis: Mosby, Inc. 2002. page 771.
• Kiran Kumar Ganji, Veena Ashok Patil,and Jiji John.
Comparative Evaluation for Biologic Width following Surgical
Crown Lengthening Using Gingivectomy and Ostectomy
Procedure. International Journal of Dentistry, 2012; 12: 1-9.
• Nitin Khuller, Nikhil Sharma. Biologic Width: Evaluation and
Correction of its Violation. J Oral Health Comm Dent
2009;3(1):20-25.
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