1. Problem Based Learning Pre-prosthetic Periodontal Surgery
Maha A. Bahammam, BDS, MSc, CAGS,
EdM, DSc
Diplomate of the American Board of Periodontology

2. Case: 1 45 years old. Female patient Healthy
Her chief complaint: ( my crowns on my lower RT back teeth always come off, I need good cement this time)
What do you think the reason is? And how would you manage that case?

3. Note where the gingival margin is!
Preoperative
Postoperative

4. What is the effect of a restorative margin on the development and health of the supracrestal attachment apparatus?

5. Success is in the details!

6. Goals of Osseous Resective Surgery
Establish physiologic probing depth
Exposing sound tooth structure or correcting an un-esthetic gingival contour

7. Supracrestal Gingival Tissue (SGT)
Bilogic Width: the juctional epithelium and connective tissue elements of the dentogingival contiuum that occupy the space between the base of the gingival crevice and the alveolar crest (Cohen, 1962)

8. Biologic Width
Gargiulo et al. described the dimensions and relation of the dentogingival junction in human. Their study established that there is a proportionate dimensional relationship between the crest of the alveolar bone, the connective tissue attachment, junctional epithelium, and the sulcus.

9. The biologic width is that zone of root surface coronal to the alveolar crest, to which the connective tissue and junctinal epithelum are attached.
Gargiulo A, Wantz F, Orban B Dimentions of the dentogindival junction in Humans. J Periodontol., 32, 261.

10. Biologic Width Sulcus depth- 0.69mm Junctional epithelium- 0.97mm
Connective tissue attachment- 1.07mm
Total (from the osseous crest to the gingival margin): 2.73mm
These are averages!!!

11. A small amount can make a BIG difference!

12. How much is enough?

13. Estimated dimention of the biologic width as being in vicinity of 2
Estimated dimention of the biologic width as being in vicinity of 2.04 mm (Gargiulo et al., 1961) ≈ 2 mm
Therefore the total dimensions of SGT (Biologic Zone) would be in vicinity of 2.73 mm. ≈3mm

14. Based on these dimensions of the SGT
Ingber et al., 1977; states that during clinical crown lengthening surgery, sufficient bone should be resected to permit 3 mm of sound tooth structure above the crest of the bone
Rosenberg et al., 1980; preferred 4 mm of tooth exposure

15. This bone resection is necessary to accommodate the SGT, which will develop in the surgical site, and yet leave sufficient tooth exposed to complete the tooth preparation
When the attachment levels are within normal limits, soft tissue excision alone will result in reformation of the predestined amount of SGT and no real gain in clinical crown length

16. The decision to restore a tooth depends on the following factors:
Degree of periodontal support lost form adjacent tooth during crown lengthening procedure
Location of furcation relative to biologic width
Ability to perform effective plaque control following placement of restoration

17. Continue Crown to root ratio
Position of tooth in the arch
Predictability of treatment procedure
Strategic value of tooth
Esthetic and phonetic consideration
Endodontic consideration
Root anatomy and morphology as it relates to post placement
Restorative requirement
Cost/ Risk/ Benefit ration relative to alternative treatment
(Case 4)

18. Indications: surgical removal of healthy periodontal tissue is sometimes necessary to facilitate a restorative treatment for the following reason:
Tooth decay at or apical to the gingival margin that prevent adequate finish line preparation
Tooth fracture bellow the gingival margin, with adequate remaining periodontal support and attachment
Teeth with insufficient interocclusal space
Mechanical retention is inadequate
Displeasing esthetics of short or uneven clinical crown lengths following excessive attrition or delayed passive eruption

19. Cost/ Risk/ Benefit Ration
What are the costs of each treatment?
What is the length of time involved?
How many visits are involved?
What is the long term prognosis?
How predictable is the procedure?

20. How do we treat this case? What do we tell the patient?

21. How do we treat this case? What do we tell the patient?

22. Contraindications for Crown Lengthening Procedures
Teeth that are not restorable, when adjacent teeth would be compromised either functionally or esthetically
When the importance of the tooth is not comparable with the extent of the procedure required to save it.

23. Post Operative Treatment
Perio packing
Medication
NSAID
Antibiotics
Analgesics
Suture removal
Completion of restoratioin

24. Possible Complication
Bleeding
Pain
Swelling
Root sesitivity
Loss of flap

25. How long to wait for healing?

26. Healing should proceed uneventfully, with the attachment of the flap to the underlying bone being completed by 14 to 21 days. Maturation and remodeling can continue for up to 6 months.
It is usually advisable to wait a minimum period of 6 weeks after the completion of the last surgical area before beginning dental restorations.
For those patients with a major cosmetic concern, it is wise to wait as long as possible to achieve a postoperative soft tissue position and sulcus that is stable.

27. The Art of Communication

28. Explaining the Procedure
What words do we use?
Cut away tissue
Grind bone
surgery

29. Weighing the choices

30. Cost/ Risk/ Benefit Ratio
What alternative treatment exists?
Extraction Bridge
Implant

31. Cost/ Risk/ Benefit Ratio
What alternative treatment exists?
Extraction
Orthodontic extrusion

32. Forced Eruption and Flap Surgery
This accomplished by moderate orthodontic force of 25 to 35 g.
Indications:
When the amount of surgical bone reduction around the affected tooth and the adjacent teeth would be excessive

33. Contraindication:
Short root length which result in inadequate crown/ root ration following extrusion
Poor root form

34. Following forced eruption, a flap procedure usually is necessary to reduce any extruded alveolar bone and to apically position the gingiva that moved coronally during extrusion
However, if a gingival supracrestal fibrotomy is performed during the extrusion process, the gingiva should not erupt with the tooth, and the need for periodontal surgery maybe eliminated

35. Advantages of Forced Eruption
Supporting bone of the adjacent teeth not sacrificed
Surgical treatment phase maybe reduced or eliminated

36. Summary
In establishing a biologic basis for crown lengthening; we should consider the following:
Finish line of the restoration should be determined prior to the surgery
If not possible, the finish line should be anticipated at surgery
Sufficient alveolar bone should be removed to permit the development of an acceptable dimension of SGT between the actual and anticipated finish line of the preparation and the alveolar crest

37. Circumferential transgingival probing (bone sounding) prior to surgery, in healthy areas in the operation site, should be the gauge for estimating the SGT compatible with individual patient requirements
The degree and configuration of osseous scalloping is determined by the surface topography of the tooth

38. Gingival form is dictated both by osseous configuration and the surface anatomy of the tooth
Restorative procedures must not disrupt the epithelial attachment and the SGT

39. Conclusions
Dental restorations and periodontal health are interrelated
The adaptation of the margins, the contours of the restoration, the proximal relationships, and the surface smoothness have a critical biologic impact on the gingiva and supporting periodontal tissues
Dental restorations therefore play a significant role in maintaining periodontal health

40. Thank You!