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Soft Tissue Grafting To Improve Aesthetics, To Reduce Dentinal Hypersensitivity, To Improve The Prognosis Of Compromised Teeth And To Augment Edentulous Ridges Prior To The Placement Of Implants

October 12, 2017
by Valentin Dabuleanu, BSc, DDS, MSc, FRCD(C)


Introduction
Over the past two decades, surgeons have shown an increased interest in mucogingival procedures to rehabilitate soft tissues around both teeth and implants, in an attempt to master our shared domain of the oral apparatus.1 A variety of techniques and materials have been studied, and sufficient high-level research exists to guide us in selecting an appropriate treatment, after making a proper diagnosis, and after controlling for local, behavioural, and systemic factors.

This article will discuss three different applications of grafting with autogenous soft tissue. It will review the diverse etiology of gingival recession, the scope of procedures, a classification system of gingival recession, the sources of donor tissue and the use of wound healing modifiers to improve grafting outcomes. Indications for both gingival augmentation and root coverage, as well as factors influencing patient selection, will be illustrated by five case presentations. This article will not discuss other procedures, existing or emerging, that are outside of the scope of autogenous soft tissue grafting.

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Rationale
The rationale behind mucogingival therapy, also known as periodontal plastic surgery, is three-fold. First, it corrects defects associated with the morphology, position, and amount of soft tissue, around both teeth and implants. Second, it manages hard tissue by way of masking areas where there are deficiencies in the underlying bone support, such as pontic site development for fixed bridges, on either teeth or implants. Third, it improves plaque control, tooth support, and tooth prognosis by an increase in keratinized tissue, it improves aesthetics by way of root coverage, and it also decreases dentinal hypersensitivity.1-3

Scope of Procedures
Mucogingival therapy encompasses gingival augmentation around teeth (i.e. a free gingival graft), root coverage (i.e. a connective tissue graft), correction of mucosal defects around implants, preservation of attached gingiva around ectopic tooth eruption (i.e. an impacted canine), removal of an enlarged frenum, prevention and management of ridge collapse associated with tooth extraction (i.e. pontic site development), and augmentation of the edentulous ridge for implant therapy.2

Source of Donor Tissue

Autogenous
Figure 1 illustrates the variety of sources of donor tissue which are available to be used for soft tissue grafting, and may not represent all the products that are currently available on the Canadian market. The coronally advanced flap (CAF) and the use of autogenous connective tissue remains the gold standard and procedure of choice for the treatment of gingival recession at single and multiple teeth. This combination provides the most optimal clinical outcome.1

Allograft
The use of acellular dermal matrix (ADM), an allograft of cadaveric origin, applied beneath a CAF has been shown to cause great variability in root coverage, from 50 to 97%, and a great variability in treatment outcome. Caution is especially suggested when using ADM for treating single gingival recessions.1 A Cochrane systematic review of 24 randomized control trials, 599 patients, with study durations of ≥ six months, found that a subepithelial connective tissue graft (SCTG), CAF alone or associated with either ADM, enamel matrix protein (EMP), or SCTG, and guided tissue regeneration (GTR) with bioabsorbable membranes may be used as root coverage procedures for the treatment of gingival recession. In cases where both root coverage and gain in width of keratinized tissue are expected, the use of SCTG is more adequate (Fig. 2). ADM may be used as an alternative treatment where connective tissue harvested from the palate is insufficient to cover the recession area.4

Figure 1

Soft tissue grafting–source of donor tissue.

Figure 2 

A subepithelial connective tissue graft provides both root coverage as well as a gain in width of keratinized tissue.

Xenograft
Porcine collagen matrix placed under a CAF for the purpose of root coverage has been used more recently, however, further studies are necessary to determine the potential benefit of this technique.1

Wound Healing Modifiers
Enamel matrix protein (EMP) in combination with a CAF alone for root coverage has been shown through histologic studies to result in the reformation of new cementum along the root surface, along with the insertion of collagen fibres. The use of EMP results in periodontal regeneration along the root. The CAF in combination with EMP has been shown to result in more root coverage than the CAF alone, and it also produces a significant increase in keratinized tissue.1 The combination of EMP with a SCTG may not only improve clinical outcomes, but it may also positively influence periodontal wound healing and regeneration (Fig. 3). EMP has been shown to regulate transforming growth factor β (TGF- β) target genes in fibroblasts from the attached gingiva of the overlying flap and from the SCTG, which may in turn positively influence periodontal regeneration along the root surface.5 EMP is available for use in Canada as Straumann® Emdogain.

Figure 3

Combining enamel matrix protein (Straumann® Emdogain) and subepithelial connective tissue graft.

Etiology of Gingival Recession
The most common cause of gingival recession is trauma (Fig. 4). Trauma can occur by way of an improper tooth brushing technique, the use of a hard-bristle toothbrush, an improper flossing technique (injury near the line angles of the tooth known as Stillman clefts – (Fig. 5), piercings and occlusal habits such as bruxism and clenching. When bacterial plaque accumulates on a tooth’s facial aspect, the resulting inflammation may also cause recession (Fig. 6). Recession caused by periodontitis is the indirect consequence of connective tissue attachment loss (Fig. 7). A herpes simplex virus infection, which causes blisters and ulcerations, may also lead to gingival recession. The etiology of gingival recession may also be varied, such that it is a combination of the above-mentioned factors.3

Figure 4

Tooth brush trauma is the most common cause of gingival recession.

Figure 5

Stillman cleft and associated recession caused by a traumatic flossing technique. Recession was grafted and flossing technique was adjusted.

Figure 6

Gingival recession of bacterial ethology caused by accumulation of plaque on a tooth’s facial aspect.

Figure 7

Gingival recession due to periodontitis, where specific periodontopathogenic bacteria provoke connective tissue attachment loss.

Classification of Gingival Recession
There are several classification systems for gingival recession. The Miller classification is used to assess anticipated root coverage, and the predictability of the procedure (Fig. 8).6 In Class I defects, the recession does not extend to the mucogingival junction (MGJ), and there is no loss of interdental bone or soft tissue. In Class II defects, recession extends to or beyond the MGJ, but there is still no loss of interdental bone or soft tissue. In Class III defects, recession extends to or beyond the MGJ with loss of interdental bone or soft tissue that is apical to the CEJ, but coronal to the apical extent of the recession. In class IV defects, recession extends beyond the MGJ, in addition to the loss of interdental bone, which extends apical to the marginal tissue recession.

Indications for Treatment

Gingival Augmentation
Gingival augmentation is indicated (Fig. 9) when recession is progressing with time, when there is discomfort during chewing or tooth brushing, in the anticipation of orthodontic treatment or when a subgingival restoration is planned where there is thin tissue.2

Free gingival grafts have a low predictability for complete root coverage, especially with deep and wide recession defects. They are effective, however, when the frenulum inserting into the gingival margin causes marginal tissue mobility. They are the technique of choice for the treatment of mandibular Miller Class III and IV recession defects, where the aim is to widen the zone of keratinized tissue and deepen the vestibule to aid home oral hygiene practices.3 An increased width of keratinized tissue around dental implants has also been found to facilitate plaque control, leading to improved indices of peri-implant mucosal health, as well as lower mean alveolar bone loss (Fig. 10).7-8

Figure 8

Miller classification system for gingival recession.

Figure 9

Gingival augmentation may be indicated when recession is progressing and when there is discomfort during chewing.

Figure 10

Increased peri-implant keratinized mucosa is associated with improved soft tissue health and reduced alveolar bone loss.

Root Coverage
Subepithelial connective tissue grafts (SCTG) are indicated (Fig. 11) when there are esthetic or cosmetic demands, when there is dentinal hypersensitivity due to exposed roots, and when a change in the topography of the marginal tissue will help to facilitate plaque control.2 By increasing the keratinized tissue, the SCTG reduces the risk of defect progression.1 The SCTG, when placed coronal to the cemento-enamel junction (CEJ), may aid in reversing recession.3

Figure 11

Root coverage procedures are indicated when there are esthetic demands.

Patient Selection
The identification and control of several local, behavioural and systemic factors will help to ensure a successful outcome with mucogingival procedures. Patients with good plaque control habits, and who are compliant with prescribed post-operative care are good candidates. Non-smokers have a lower risk for postsurgical infection, and are more likely to have complete root coverage than those who smoke.1

Case 1: Patient profile, concerns, diagnosis
A healthy 20-year-old female who had previously received two connective tissue grafts by another dentist, presented for treatment of gingival recession of the lower incisors (Fig. 12). Despite previous treatment, the recession continued to progress and the patient reported discomfort during chewing and tooth brushing. She requested a retreatment that was predictable, that would reduce her discomfort, and that would improve the prognosis of her lower incisors. The patient had a healthy periodontium, with localized Miller class III recession at teeth 31, 41, and 42, and a shallow mandibular labial vestibule with frenal pull. The recession extended near to the MGJ, and the loss of interdental bone was apical to the CEJ, but coronal to the apical extent of the recession (Fig. 13). Scar tissue from the previous surgeries was evident.

Figure 12

Initial.

Figure 13

Diagnosis.

The patient was advised that a free gingival graft was indicated to widen the zone of keratinized tissue, to deepen the vestibule, to decrease the risk of future recession and to achieve partial root coverage. The reduction, but not complete elimination, of dentinal hypersensitivity was put in perspective and discussed. She was made aware that post-operative restorative treatment with composite resin might be necessary to completely eliminate any remaining sensitivity after full graft healing. Informed consent was obtained.

Surgical Treatment
The buccal root convexities of teeth 31, 41, and 42 were reduced by thorough root planing (Fig. 14). A partial-thickness flap was reflected and secured apically at the recipient site (Figs. 15 & 16). A sterile foil template was used as a guide for harvesting the graft (Figs. 17 & 18). An epithelium-connective tissue graft, harvested from the hard palate, was secured at the recipient site with 5-0 chromic gut absorbable sutures. A bovine collagen-derived resorbable wound dressing was applied to the donor site and secured with 4-0 chromic gut absorbable sutures. Cyanoacrylate oral adhesive (PeriAcryl®–Citagenix) was placed over the donor site and at the coronal margins of the recipient site (Figs. 19-21). An Essix appliance was inserted with gauze packing to assist in providing palatal hemostasis.

Figure 14

Root planning.

Figure 15

Incisions.

Figure 16

Partial-thickness flap.

Figure 17

Foil template at recipient site.

Figure 18

Foil template for graft harvest.

Figure 19

Harvest site co-aptation.

Figure 20

Connective tissue-epithelium graft affixed at recipient site.

Figure 21

Application of cyanoacrylate oral adhesive.

The patient was seen for one-week, two-weeks, and one-month post-operative checks. At one-month, all sutures had dissolved, and the graft appeared revascularized and was in the process of epithelial maturation with the formation of a keratin layer.2 The donor site was healing predictably (Figs. 22 & 23). At seven months, the graft site showed good incorporation and blended with the adjacent tissue. A wide zone of keratinized tissue was achieved, the vestibule was deepened and frenal pull was eliminated. The interdental papillae were fully retained (Fig. 24). The donor site showed complete regeneration of the harvested tissue, without any evidence of scarring (Fig. 25). A comparison of the initial site and sevent-month postoperative follow-up shows evidence of partial root coverage at teeth 31, 41, and 42, most prominent at tooth 31 (Fig. 26).

Figure 22

One-month post-operative, recipient site.

Figure 23

One-month post-operative, donor site.

Figure 24

Seven-month post-operative, recipient site.

Figure 25

Seven-month post-operative, donor site.

Figure 26

Initial and seven-month comparison.

Case 2: Patient profile, concerns, diagnosis, initial treatment
The second case presented is a healthy 40-year-old male with generalized aggressive periodontal disease (Fig. 27). His first round of treatment was both non-surgical and surgical, and included extraction of the lower incisors. Both teeth 33 and 43 had Miller Class IV recession defects, minimal attached gingiva, a short labial vestibule, and frenal pull (Fig. 28). The patient reported discomfort during chewing and brushing, and requested a treatment that would reduce his symptoms.

The patient was advised that free gingival grafts were indicated at teeth 33 and 43 to widen the zone of keratinized tissue, deepen the vestibule to aid home oral hygiene practices, and to decrease the risk of future recession. Informed consent was obtained.

Figure 27

Initial.

Figure 28

Diagnosis.

Surgical Treatment
Free gingival grafts were placed at teeth 33 and 43 in two separate procedures, spaced one-month apart, using a similar technique as previously described (Figs. 29 & 30). The patient was seen for one-week, two-week, one-month, and six-month post-operative checks (Figs. 31 & 32). At six months, both grafts showed good incorporation. A wide zone of keratinized tissue was achieved around both canine teeth, the vestibule was deepened, and frenal pull was eliminated. The long-term prognoses of the mandibular canine teeth were improved.

Figure 29

Recipient site preparation and graft harvest.

Figure 30

Graft affixation and donor site stabilization.

Figure 31

Two-week post-operative.

Figure 32

Initial and six-month comparison.

Case 3: Patient profile, concerns, diagnosis
The third case presented is a healthy 23-year-old male, referred from is orthodontist to consider grafting of recession at multiple teeth, which was increasing following orthodontic treatment (Fig. 33). The patient’s mandible experienced continued growth following completion of orthodontics, resulting in a traumatic occlusion. He also reported a history of aggressive tooth brushing. The patient’s main concern was that his gingival recession was increasing over time. Miller Class I recession was diagnosed at all canine and first premolar teeth. These same teeth also had composite restorations, which masked the full extent of the recession (Fig. 34).

The patient was advised that connective tissue grafts were indicated at all canine and first premolar teeth. The objectives were to achieve root coverage, eliminate dentinal hypersensitivity once the composite restorations would be removed from the exposed roots, and to increase the zone of keratinized tissue in order to reduce the risk of future recession. Informed consent was obtained.

Figure 33

Initial.

Figure 34

Diagnosis.

Surgical Treatment
Subepithelial connective tissue grafts (SCTG) were placed at teeth in all four quadrants, in four separate surgical sessions, spaced one-month apart. Partial thickness buccal pouches were reflected using the envelope technique, while keeping the interproximal papilla intact. The composite restorations were removed. The buccal root convexities of recipient teeth were reduced by thorough root planing. A SCTG was harvested from the palate using a trap-door approach.2 The graft was sectioned into two pieces and secured within each pouch using chromic gut absorbable sutures. The palate was co-apted using chromic gut absorbable sutures. Cyanoacrylate oral adhesive (PeriAcryl®–Citagenix) was placed over-top the donor site and coronal margins of each recipient site (Fig. 35). An Essix appliance was inserted with gauze packing to assist in providing palatal hemostasis.

The patient was seen for one-week, two-week, one-month, and six-month post-operative checks (Figs. 36 & 37). At six months, the maxillary grafts showed good incorporation. Full root coverage was obtained and a wide zone of keratinized tissue was achieved around both canine teeth.

Figure 35

Recipient site preparation, graft harvest and affixation, donor site stabilization.

Figure 36

One-week and one-month post-operative.

Figure 37

Initial and six-month comparison.

Case 4: Patient profile, concerns, diagnosis
A healthy 50-year-old female was referred by her general dentist to consider treatment of recession of the mandibular right posterior dentition (Fig. 38). Composite restorations were placed on teeth 44, 45, and 46 over 10 years prior. The patient did not report dentinal hypersensitivity. Her main concern was that the gingival recession was increasing despite the restorative treatment and that plaque control was challenging in this area. Generalized Miller Class III recession was diagnosed. The composite restorations masked the full extent of the recession (Fig. 39).

The patient was advised that a connective tissue graft was indicated to obtain root coverage, to eliminate any dentinal hypersensitivity once the composite restorations would be removed from the exposed roots, and to increase the zone of keratinized tissue in order to reduce the risk of future recession. Informed consent was obtained.

Figure 38

Initial.

Figure 39

Diagnosis.

Surgical Treatment
The composite restorations were removed at teeth 44, 45 and 46. The buccal root convexities of recipient teeth were reduced by thorough root planing. Three partial thickness buccal pouches were connected using the tunnel technique, while keeping the interproximal papilla intact. A SCTG was harvested from the palate using a trap-door approach.2 The palate was co-apted using chromic gut absorbable sutures (Fig. 40). The graft was immersed in Straumann® Emdogain. Straumann® PrefGel was applied to the root surfaces of the recipient sites. The graft was introduced and secured within the tunnel using polypropylene monofilament sutures (Fig. 41). Sling sutures were used to coronally position the graft and overlying flap separately. Coe-PakTM periodontal dressing was used to cover the donor site (Fig. 42).

Figure 40

Restoration removal, tunnel preparation, graft harvest.

Figure 41

Application of Straumann® PrefGel and Emdogain, graft insertion.

Figure 42

Graft affixation, donor site stabilization.

The patient was seen for one-week, two-week, and one-month post-operative checks (Figs. 43 & 44). At one-month, the graft showed good incorporation. Partial root coverage was obtained and a wide zone of keratinized tissue was achieved around all recipient teeth. The site will be monitored for an additional five months, and a decision will then be made together with the patient and their referring dentist to re-cover the remaining gingival recession with composite restorations, to eliminate any remaining dentinal hypersensitivity and to facilitate plaque control.

Figure 43

Two-week and one-month post-operative.

Figure 44

Initial and one-month comparison.

Case 5: Patient profile, concerns, diagnosis
A healthy 33-year-old female was referred by her general dentist to consider bone grafting and implant placement to replace missing teeth in the bilateral posterior mandible. Missing teeth 37, 36, 35, 45, 46, and 47 were lost five years prior to the consultation (Fig. 45). The patient’s main concern was to have a fixed prosthetic replacement of her missing teeth. A Cone Beam CT scan revealed severe bilateral Seibert (1983) Class III ridge deficiencies in the posterior mandible, or a severe loss of both ridge height and width (Fig. 46). There was also a complete lack of buccal keratinized tissue in the bilateral posterior mandible.

The patient had already seen an Oral & Maxillofacial Surgeon for consultation regarding an extra-oral bone grafting procedure (i.e. hip graft) to regenerate the missing bone. She declined this treatment option. Bilateral gingival onlay grafting was offered, followed by short implant placement, to be restored with splinted crowns. Informed consent was obtained.

Figure 45

Initial.

Figure 46

CBCT scan.

Surgical Treatment
Free gingival grafts were placed in quadrants 3 and 4 in two separate procedures, spaced one-month apart, using a similar technique as previously described (Figs. 47 & 48). The patient was seen for one-week and two-week post-operative checks (Fig. 49). Straumann® Standard Roxolid SLActive Tissue Level implants were then placed at sites 37 (4.8 x 6mm WN), 36 (4.8 x 6mm WN), 35 (4.1 x 10mm RN) and 45 (4.1 x 8mm RN), 46 (4.8 x 6mm WN), 47(4.8 x 6mm WN) in two procedures, after two months of graft healing on each side (Fig. 50).

The patient was seen for one-week and one-month post-operative checks. Both sites healed predictably, and the implants were surrounded by a thick band of keratinized mucosa (Fig. 51). Splinted implant-supported fixed dental prostheses were installed three months after implant placement, after implant integration was verified (Fig. 52).

Figure 47

Graft harvest.

Figure 48

Graft affixation and donor site stabilization.

Figure 49

Two-week post-operative.

Figure 50

Implant placement.

Figure 51

Initial and three-month post-implant placement.

Figure 52

Implant restoration.

Conclusion
This article discussed three different applications of grafting with autogenous soft tissue. Five cases were utilized to demonstrate variations in donor and recipient site management techniques. Mucogingival procedures are predictable when they are based on sound diagnostic criteria, and when factors influencing the outcome are identified and controlled. Selecting the right procedure and discussing all aspects of it with the patient will ensure a healthy balance between likely outcomes and patient expectations.OH

Oral Health welcomes this original article.

References

  1. Cairo, F. Periodontal plastic surgery of gingival recessions at single and multiple teeth. Periodontology 2000. 2017; 75: 296-316.
  2. Lindhe J, editor. Clinical Periodontology and Implant Dentistry. 5 ed. Oxford: Blackwell Munskgaard; 2008
  3. Zuchelli G. Mucogingival Esthetic Surgery. Rho (Milan): Quintessenza Edizioni S.r.l.; 2013
  4. Chambrone L, et al. Root-coverage procedures for the treatment of localized recession-type defects: a Cochrane systematic review. Journal of Periodontology. 2010; 81: 452-478.
  5. Sculean A, et al. The modified coronally advanced tunnel combined with an enamel matrix derivative and subepithelial connective tissue graft for the treatment of isolated mandibular Miller Class I and II gingival recessions: A report of 16 cases. Quintessence International. 2014: 1-7.
  6. Miller PD Jr. A classification of marginal tissue recession. The International Journal of Periodontics & Restorative Dentistry. 1985; 5: 8-13.
  7. Bouri, A, et al. Width of keratinized gingiva and the health status of the supporting tissues around dental implants. International Journal of Oral & Maxillofacial Implants. 2008; 23: 323-326.
  8. Roccuzzo M, et al. Keratinized mucosa around implants in partially edentulous posterior mandible: 10-year results of a prospective comparative study. Clinical Oral Implants Research. 2015; 00: 1-6.

Dr. Valentin Dabuleanu maintains a private practice in Toronto limited to periodontics and implant surgery, in a combined periodontal, endodontic, and orthodontic practice with Dr. Mary Dabuleanu, Endodontist, Dr. Natoosha Nargaski, Orthodontist and alongside the family practices of Dr. Tudor Dabuleanu and Dr. Emilia Nicola, General Dentists. Valentin is a Fellow of the Royal College of Dentists of Canada in Periodontology. He obtained his DDS from the University of Toronto in 2010, and completed a general practice residency at Vancouver General Hospital. Valentin completed his MSc degree and speciality training in Periodontology at the University of British Columbia in 2014. He can be reached at valentindab@gmail.com.