Jan Lindhe. Clinical Periodontology

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MUCOGINGIVAL THERAPY — PERIODONTAL PLASTIC SURGERY • 605

Fig. 27-41. (a-d)

Free connective tissue graft combined with a coronally advanced flap procedure

(see text for explanation).

(

e) The 1-year post-treatment result.

Free soft tissue graft procedures

A free soft tissue graft of masticatory mucosa is usu-

ally selected when there is no acceptable donor tissue

present in the area adjacent to the recession defect or

when a thicker marginal tissue is desirable. The pro-

cedure can be used for the treatment of a single tooth

as well as for groups of teeth. The graft used may

either be (1) an epithelialized graft or (2) a subepi-

thelial connective tissue graft of palatal masticatory

mucosa.

Epithelialized soft tissue graft

The epithelialized free soft tissue graft procedure can

be performed either as a two-step surgical technique,

where an epithelialized free soft tissue graft is placed

apical to the recession and following healing is

coronally positioned over the denuded root (Fig. 27-

39) (Bernimoulin et al. 1975, Guinard & Caffesse 1978),

or as a one-step technique, in which the graft is placed

directly over the root surface (Fig. 27-40) (Sullivan &

Atkins 1968a,b, Miller 1982). The latter technique has

been the one most commonly used.

Technique

The principles of utilizing free mucosal grafts were

outlined by Sullivan & Atkins (1968a,b) and later

modified by Miller (1982).

•

Before any incisions the exposed root surface is

carefully scaled and root planed (Fig. 27-40a). The

convexity of the root may be reduced to minimize

the mesiodistal avascular recipient bed.

•

As in the treatment with pedicle grafts, the prepa-

ration of

the recipient bed is

crucial for the success of

free graft procedure. A 3-4-mm-wide recipient con-

nective tissue bed apical as well as lateral of the

606 • CHAPTER

Fig. 27-42. (a-e)

Free connective tissue graft combined with a double papilla flap procedure.

(f) The 1-year post-

treatment

result.

recession defect should be prepared (Fig. 27-40b).

The area is demarcated by first placing a horizontal

incision, at the level of the cemento-enamel junc-

tion, in the interdental tissue on each side of the

tooth to be treated. Subsequently, two vertical inci-

sions, extending from the incision line placed in the

interdental tissue to a level approximately 4-5 mm

apical of the recession, are placed. A horizontal

incision is then made, connecting the two vertical

incisions at their apical termination. Starting from

an intracrevicular incision, a split incision is made

to sharply dissect the epithelium and the outer por

tion of the connective tissue within the demarcated

area.

•

To ensure that a graft of sufficient size and proper

contour is removed from the donor area, a foil tem-

plate of the recipient site is prepared. This template

is transferred to the donor site, the palatal mucosa

in the region of the premolars, and the required size

of the graft is outlined by a shallow incision. A graft

with a thickness of 2-3 mm is then dissected from

the donor area (Fig. 27-20c-d). It is advocated to

place sutures in the graft before it is cut completely

free from the donor area since this may facilitate its

transfer to the recipient site. Following the removal

of the graft, pressure is applied to the wound area

for control of bleeding.

•

The graft is immediately placed on the prepared

recipient bed. In order to immobilize the graft at the

recipient site the sutures must be anchored in the

periosteum or in the adjacent attached gingiva.

Adequate numbers of sutures are placed to secure

close adaptation of the graft to the underlying

connective tissue bed and root surface (Fig. 27-40c).

MUCOGINGIVAL THERAPY — PERIODONTAL PLASTIC SURGERY •

607

Fig. 27-43. (a-c)

Free connective tissue graft procedure — the "envelope technique

(see text for explanation) (Courtesy of

Dr M. Cattabriga). (d) The 1-year post-treatment result (Courtesy of Dr P. Cortellini).

Before the placement of a periodontal dressing,

pressure is exerted against the graft for some min-

utes in order to eliminate blood between the graft

and the recipient bed. The wound in the donor area

in the palate is, following the control of the bleeding,

covered by a periodontal dressing. To maintain the

dressing in place during the healing phase, the use

of an acrylic plate may often be required.

• The sutures and periodontal dressing are usually

maintained for 2 weeks. The appearance of a grafted

area after 3-month healing is shown in Fig. 27-40d.

A gingivoplasty may sometimes be indicated to

achieve a satisfactory esthetic appearance of the

grafted area (Fig. 27-40e-f).

Connective tissue graft

The technique utilizing a subepithelial soft tissue

graft, i.e. the connective tissue, involves the placement

of the graft directly over the exposed root and the

mobilization of a mucosal flap to be coronally (Fig.

27-

41) or laterally (Fig. 27-42) moved for coverage of

the

graft (Langer & Langer 1985, Nelson 1987, Harris

1992, Bruno 1994). An alternative technique is to place

the base of the connective tissue graft within an "en-

velope" prepared by an undermining partial thick-

ness incision from the soft tissue margin, i.e. part of

the graft will rest on the root surface coronal to the soft

tissue margin (Fig. 27-43) (Raetzke 1985, Allen 1994).

For the treatment of multiple adjacent recessions, a

multi-envelope recipient bed ("tunnel") may be pre-

pared (Zabalegui et al. 1999). The subepithelial con-

nective graft is harvested from the palate or the retro-

molar pad by the use of a "trap door" approach (Fig.

27-44d-f). Compared to the epithelialized graft, the

connective tissue graft is preferable due to less inva-

sive palatal wound and improved esthetic result.

6o8 •

CHAPTER

Fig. 27-44a-f.

"Trap-door" technique for harvest of a free connective tissue graft

(see text for explanation).

Technique

face of the interdental tissue on each side of the teeth

Connective tissue graft covered by a coronally advanced flap

to be treated (Fig. 27-41a). The incision should be

(Fig. 27-41)

placed just coronal to the intended level of root

• A horizontal incision is first made in the facial sur-

coverage. Care should be taken not to decrease the

MUCOGINGIVAL THERAPY — PERIODONTAL PLASTIC SURGERY • 609

Fig. 27-45a-c.

Free connective tissue graft procedure — the "envelope technique".

Schematic drawings illustrating the sur

gical technique (see text for explanation).

height of the papillae. Subsequently, starting from

the line of incision in the interdental area at the

mesial and distal termination of the surgical area,

two divergent, vertical incisions are placed and ex-

tended well beyond the mucogingival line.

•

A split thickness flap is then prepared by sharp

dissection and elevated to such an extent that it can

be coronally repositioned at the level of the ce-

mento-enamel junction without tension (Fig. 27-

41c).

•

A subepithelial connective tissue graft of mastica-

tory mucosa is harvested on the palatal aspect of the

maxillary premolars (or from the retromolar pad)

by the use of a "trap door" approach (Fig. 27-44).

Before incisions are placed, the available thickness

of the mucosa is estimated by the use of the tip of

the syringe. A horizontal incision, perpendicular to

the underlying bone surface, is made approxi-

mately 3 mm apical to the soft tissue margin (Fig.

27-44a). The mesiodistal extension of the incision is

determined by the graft size required. To facilitate

the removal of the graft, a vertical releasing incision

can be made at the mesial termination of the pri-

mary incision. An incision is then placed from the

line of the first incision and directed apically to

perform a split incision of the palatal mucosa (Fig.

27-44b-f). A small periosteal elevator or the scalpel

is used to release the connective tissue graft from

the bone. Sutures may be placed in the graft before

it is released completely free from the donor area to

facilitate its placement at the recipient site.

•

The graft is immediately placed in the recipient site

(Fig. 27-41d) and secured in position with inter-

rupted sutures or a sling suture. The mucosal flap

is then sutured to cover the connective tissue graft.

Interrupted sutures are placed in the papilla regions

as well as along the wound of the vertical incisions.

A surgical dressing may be applied for protection of

the area during the first week of healing.

The "envelope" technique (Fig. 27-45)

•

With the use of the "envelope" technique the recipi-

ent site is prepared by first eliminating the sulcular

epithelium by an internal beveled incision (Fig. 27-

45a). Secondly, an "envelope" is prepared apically

and laterally of the recession by split incisions (Fig.

27-45b). The depth of the preparation should be 3-5

mm in all directions. In apical direction, the prepa-

ration of the site should extend beyond the mu-

cogingival junction to facilitate the placement of the

connective tissue graft and to allow for coronal

advancement of the mucosal flap at time of sutur-

ing.

•

A foil template may be used for the harvest of an

appropriately sized connective tissue graft. The

graft, which is obtained by the "trap door" ap-

proach described above (Fig. 27-44), is inserted into

the prepared "envelope" and positioned to cover the

exposed root surface (Fig. 27-45c-d).

•

Sutures are placed to secure graft position (Fig. 27-

45d). A crossed sling suture may be placed to

coronally advance the mucosal flap. Pressure is ap-

610 • CHAPTER

Fig. 27-46a-d.

Free connective tissue graft procedure — the

tunnel technique

Schematic drawings illustrating the surgi-

cal technique (see text for explanation).

plied for 5 min to closely adapt the graft to the root

surface and covering soft tissue. Application of a

periodontal dressing is usually not required.

Fig. 27-43 shows the treatment of a recession defect

with the "envelope" technique.

The "tunnel" technique (Fig. 27-46)

•

In case multiple adjacent recessions are to be

treated, "envelopes" are prepared for each tooth as

described above. However, the lateral split incisions

are extended so that the multi-envelopes are con-

nected mesially and distally to form a mucosal tun

nel. Care should be taken to avoid detachment of

the papillae.

•

The graft is gently positioned inside the tunnel and

its mesial and distal extremities are fixed with two

interrupted sutures. Sling sutures may be placed to

coronally advance the mucosal flap over the ex-

posed portions of the connective tissue graft. Pres-

sure is applied for 5 min to closely adapt the graft

to the root surface and covering soft tissue. Appli-

cation of a periodontal dressing is often not re-

quired.

Clinical outcome of root coverage procedures

Independent of the modality of surgical procedure

used to obtain soft tissue root coverage, shallow resid

ual probing depths, gain in clinical attachment and an

increase in gingival height are the common charac-

teristics of treatment outcome. Although the major

indication for performing root coverage procedures is

esthetic demands by the patient, almost no studies

have included assessments of esthetics as an endpoint

of success. Instead, the common outcome variable

used is the amount of root coverage achieved, ex-

pressed as a percentage of the initial depth of the

recession. In some studies also the proportion of

treated sites showing complete root coverage is re-

ported.

Root coverage

An overall comparison of the treatment outcome of

root coverage procedures is hampered by the fact that

comparatively few studies have presented well-docu-

mented clinical results. A summary of published stud

ies providing data for calculation of the average

amount of the initial recession defect that has been

successfully covered following treatment (Table 27-1)

shows that an average of 63-86% root coverage may

be expected, depending on the treatment procedure

used. However, the variation (range) in treatment out

come for the various procedures, both within and

between studies, is large. This indicates that the pro-

cedures are operator sensitive and/or that factors in-

fluencing the treatment outcome have not been ade-

quately considered. Complete coverage of the reces-

sion defect is the ultimate goal of the therapy. Table

27-2 summarizes available data on the predictability

of complete root coverage with the use of the various

MUCOGINGIVAL THERAPY — PERIODONTAL PLASTIC SURGERY • 611

Table 27-1. Summary of the data available in the literature on the amount of root coverage obtainable with

various procedures

Root coverage procedure

Root coverage

No. of studies

No.

of patients/

teeth

Mean

of initial

recession

Range

Rotational flaps

222/235

68% 41-74

Coronally advanced flap

216/416

80% 55-99

Guided tissue regeneration

576/682

75% 48-94

Free connective tissue graft 30

589/796

86% 53-98

Epithelialized free soft tissue graft

335/491

63% 11-87

Table 27-2. Summary of the data available in the literature on the predictability of complete root coverage fol

lowing the use of various procedures

Root coverage procedure

Complete root coverage

No. of studies

No.

of patients/

teeth

Mean

of teeth

Range

Rotational flaps

30/30 43%

Coronally advanced flap

188/388

50% 9-95

Guided tissue regeneration

344/440

36% 0-75

Free connective tissue graft 25

532/715

61% 0-93

Epithelialized free soft tissue graft

253/380

28% 0-90

procedures. The average percentage of complete root

coverage following pedicle or free graft procedures

varies between 28% and 61%; the lowest figure for the

epithelialized soft tissue graft and the highest for the

connective tissue graft procedure. The lower predict-

ability of complete root coverage with the GTR proce-

dure, compared to the coronally advanced flap proce-

dure, has been associated with the problem of mem-

brane exposure during healing (Trombelli et al. 1995),

but whether a bioabsorbable or a non-biodegradable

barrier membrane is used does not seem to affect the

treatment outcome (Roccuzzo et al. 1996).

Short-term clinical trials comparing the treatment

outcome of the two modalities of free soft tissue grafts

(

Sbordone et al. 1988, Daniel & Cheru 1990, Jahnke et

al. 1993) have shown that the connective tissue graft

results in superior root coverage compared to the

epithelialized free soft tissue graft. The color match of

the connective tissue grafted area to the adjacent

gingiva is esthetically also more favorable with the

connective tissue graft than that of an epithelialized

free graft.

Factors influencing the degree of root coverage

Patient-related factors

As with other surgical periodontal treatment proce-

dures, poor oral hygiene following the procedure will

negatively influence the success of root coverage pro-

cedures (Caffesse et al. 1987). Also, the predominant

causative factor in the development of gingival reces-

sion is toothbrushing trauma, and hence this factor

has to be corrected to secure an optimal outcome of

any root coverage procedure. Whether smoking may

negatively influence the outcome of root coverage

procedures is still a controversial issue. Some studies

have reported less favorable outcome in terms of root

coverage following free graft and GTR procedures in

smokers (Miller 1987, Trombelli & Scabbia 1997,

Muller et al. 1998, Zucchelli et al. 2000), while other

studies have shown no differences between smokers

and non-smokers (Tolmie et al. 1991, Harris 1994).

Site-related factors

Among site specific factors, the level of interdental

periodontal support may be of greatest significance

for the outcome of root coverage procedures. From a

biological point of view complete root coverage is

achievable in Class I and II type recession defects (Fig.

612 •

CHAPTER

Fig. 27-47a-b. Buccal recession defects but no loss of

periodontal support at proximal surfaces (a). Complete

root coverage can be achieved. (b) 3-year follow-up.

Fig. 27-48. A deep buccal recession at tooth 11 (a). The

tooth has loss of support at proximal sites (Miller Class

III) and complete root coverage is not achievable. Also

neighboring teeth show recessions at all tooth surfaces.

(b) 2-year healing result following attempted root cov-

erage at the facial aspect of tooth 11. The coronal posi

tion of the soft tissue margin is defined by the exten-

sion of proximal loss of periodontal support.

Fig. 27-49. Increased dimension of keratinized tissue 1

year following root coverage with a coronally ad-

vanced flap procedure. Before (a) and 1-year postopera

tively (b). Arrows indicate the position of the mu-

cogingival line.

27-47), while when loss of connective tissue attach-

ment also involves proximal tooth sites (Class III-IV

recession defects), only partial facial root coverage is

obtainable (Miller 1985b) (Fig. 27-48).

An additional factor shown to influence the degree

of attainable root coverage is the dimensions of the

recession defect. Less favorable treatment outcome

has

been reported at sites with wide (> 3 mm) and

deep (>_

5 mm) recessions (Holbrook & Ochsenbein

1983, Pini

Prato et al. 1992, Trombelli et al. 1995).

Wennstrom &

Zucchelli (1996) reported in a study comparing the

treatment effect of coronally advanced

flap and free

connective tissue graft procedures that

complete root

coverage was observed in only 50% of

the defects with

an initial depth of 5 mm compared

to 96% in shallower

defects. In a controlled clinical

trial Pini Prato et al. (

1992) treated 50 teeth with a

coronally advanced flap

procedure, either with or

without the use of a non-degradable membrane bar-

rier. The mean percentage root coverage at the 18-

month follow-up examination was 73% with and 71%

without the use of a barrier, and a subsequent 4-year

follow-up report revealed long-term stability of

achieved root coverage for both procedures (Pini

Prato

et al. 1996). The authors suggested that a more

favorable result with respect to root coverage might

obtained with the GTR procedure in sites with deep

(>_

5 mm) recession defects as compared to the

coronally

advanced flap. At the 18-month examination the

coverage was 77% with and 66% without the

inclusion

of a membrane barrier in the treatment pro

cedure.

However, the data presented in Table 27-2,

showing

that the predictability of complete root cov

erage is

markedly reduced with the use of barrier

membranes,

limit the justification to utilize the GTR

procedure in

the treatment of recession defects.

MUCOGINGIVAL THERAPY — PERIODONTAL PLASTIC SURGERY • 613

The pretreatment gingival height apical to the re-

cession defect is not correlated to the amount of root

coverage obtained (Romanos et al. 1993, Harris 1994).

Technique-related factors

Several technique-related factors may influence the

treatment outcome of a pedicle graft procedure. A

positive association between recession reduction and

the thickness of the flap was shown by Baldi et al.

(

1999). Complete root coverage at sites with Miller

Class I-II recessions was obtained only when the flap

thickness was 0.8 mm. However, whether a full or

split thickness pedicle graft is used for root coverage

was not found to influence the treatment outcome

(

Espinel & Caffesse 1981).

Flap tension has been reported to be an important

factor for the outcome of the coronally advanced flap

procedure. The best clinical result is achieved if the

flap is passively adapted to the root surface (Allen &

Miller 1989, Pini Prato et al. 2000a). In the study by

Pini Prato et al. (2000a) the tension in coronally ad-

vanced flaps was measured to compare the amount of

recession reduction in sites with and without residual

flap tension. At the test sites, which had an average

residual tension of 6.5 g, the root coverage amounted

to 78% 3 months post-surgically and 18% of the treated

sites showed complete root coverage, whereas the

control sites without or with only minimal remaining

tension demonstrated a mean root coverage of 87%

and complete root coverage in 45% of the cases. Fur-

thermore, in the test group a statistically significant

negative association was shown between the magni-

tude of residual tension in the flap and the amount of

recession reduction.

Although the connective tissue areas lateral to the

recession defect may be considered important for the

retention of the advanced flap when positioned over

the root surface, the dimension of the interdental pa-

pilla is not a prognostic factor for the clinical outcome

of the root coverage procedure (Saletta et al. 2001).

With regard to free graft procedures, the thickness

of the graft is a factor influencing the success of treat

ment procedure (Borghetti & Gardella 1990). A thick-

ness of the free graft of about 2 mm is recommended.

Increased

gingival

height

An increased apicocoronal height of gingiva is found

following all procedures in which pedicle grafts of

adjacent gingiva or free grafts from the palate have

been placed over the recession defect. It is interesting

to note, however, that an increased gingival height is

also a common finding following a coronally ad-

vanced flap procedure only involving the existing

gingiva apical to the recession (Fig. 27-49). This find-

ing may be explained by several events taking place

during the healing and maturation of the marginal

tissue. Granulation tissue formation derived from the

periodontal ligament tissue will form a connective

tissue similar to the one of gingiva and with the po-

tential to induce keratinization of the covering epithe-

lium (Karring et al. 1971, Lundberg & Wennstrom

1988). A second factor to consider is the tendency of

the mucogingival line to regain its "genetically" de-

fined position following its coronal "dislocation" with

the coronally advanced flap procedure used to

achieve root coverage. Support for the concept that the

mucogingival line over time will regain its original

position is generated from a study by Ainamo et al.

(

1992). The authors performed an apically reposi-

tioned flap procedure in the mandibular anterior

tooth region, which resulted in a 3-mm apical dis-

placement of the mucogingival line. The re-examina-

tion after 18 years showed no differences in position

of the mucogingival line between sites treated with the

apically repositioned flap and contralateral control

sites treated with a procedure not interfering with the

mucogingival line, indicating that the mucogingival

line had regained its original position.

Soft tissue healing against the covered root

surface

Although successful treatment outcome of gingival

recessions by pedicle grafts or free grafts has been

reported in a number of publications (for review see

Wennstrom 1996), it is debated to which extent this

type of treatment results in new connective tissue

attachment or epithelial attachment. However, inde-

pendent of the quality of attachment formed, the root

coverage procedures evidently rarely result in the

formation of a deep periodontal pocket.

Healing of pedicle soft tissue grafts

In the areas surrounding the recession defect, i.e.

where the recipient bed consists of bone covered by

connective tissue, the pattern of healing is similar to

that observed following a traditional flap operation.

Cells and blood vessels from the recipient bed as well

as from the tissue graft invade the fibrin layer, which

gradually becomes replaced by connective tissue. As

early as 1 week later a fibrous reunion is established

between the graft and the underlying tissue.

Healing in the area where the pedicle graft is in

contact with the denuded root surface was studied by

Wilderman & Wentz (1965) in dogs. According to these

authors the healing process can be divided into four

different stages (Fig. 27-50).

The adaptation stage (from 0 to 4 days)

The laterally repositioned flap is separated from the

exposed root surface by a thin fibrin layer. The epithe

lium covering the transplanted tissue flap starts to

proliferate and reaches contact with the tooth surface

at the coronal edge of the flap after a few days.

The proliferation stage (from 4 to 21 days)

In the early phase of this stage the fibrin layer between

the root surface and the flap is invaded by connective

tissue proliferating from the subsurface of the flap. In

614 • CHAPTER

Fig. 27-50. Schematic drawing illustrating healing following treatment of a localized soft tissue recession with a

pedicle graft (a). (b) Cross-section through the area immediately after operation. The framed areas (1-4) illustrate the

four stages into which the healing process can be divided. (c) Area after healing. Approximately 50% of the suc-

cessfully covered defect may show new connective tissue attachment.

contrast to areas where healing occurs between two

connective tissue surfaces, growth of connective tissue

into the fibrin layer can only take place from one

surface. After 6-10 days a layer of fibroblasts is seen in

apposition to the root surface. These cells are believed

to differentiate into cementoblasts at a later stage of

healing. At the end of the proliferation stage, thin

collagen fibers are formed adjacent to the root surface,

but a fibrous union between the connective tissue and

the root has not been observed. From the coronal edge

of the wound, epithelium is proliferating apically

along the root surface. According to Wilderman &

Wentz (1965), the apical proliferation of epithelium

may stop within the coronal half of the defect, al-

though further downgrowth of epithelium was also

frequently observed.

The attachment stage (from 27 to 28 days)

During this stage of healing thin collagen fibers be-

come inserted in a layer of new cementum formed at

the root surface in the apical portion of the recession.

The maturation state

This last stage of healing is characterized by continu-

ous formation of collagen fibers. After 2-3 months,

bundles of collagen fibers are inserting into the cemen

tum layer on the curetted root surface in the apical

portion of the recession.

Results of experimental studies in monkeys and

dogs on the healing characteristics of the periodontal

wound have been interpreted to indicate that gingival

connective tissue lacks the ability to form a new con-

nective tissue attachment, but may induce root resorp

tion (see Chapter 28). This finding is of particular

interest when considering the rationale for the treat-

ment of recession defects by free or pedicle soft tissue

grafts. Since in these surgical procedures gingival con

nective tissue is placed in contact with a denuded root

surface, root resorption should be expected to occur.

The reason why it is not a common complication

following this type of treatment can be explained by

two possible events. Either cells from the periodontal

ligament form a fibrous attachment to the root surface

or epithelial cells proliferate apically, forming a root

protective barrier (long junctional epithelium) to-

wards the gingival connective tissue.

Histologic studies on whether it is the one or the

other type of attachment that results following treat-

ment of recessions with pedicle grafts indicate that

new connective tissue attachment with cementum for

mation may be formed in part of the defect. In the

study by Wilderman & Wentz (1965) a new connective

tissue attachment of around 2 mm and an epithelial