Periodontics

Mucogingival surgical procedures: A review of the iiteratureJilireza Haeri, MS, DMD, MHSVFrancis G. Serio, DMD, M S "

This article provides an in-depth review of the iiterature on mucogingival surgical techniques. Indicationsand contraindications of various surgical procedures are discussed with reference to the literature. Sur-gical techniques and indications for increasing the zone of keratinized tissue, such as free autogenousgrafts, applications of freeze-dried skin, and dermal matrix allografts, are described. Procedures to attainroot coverage, such as various autogenous grafts and guided tissue regeneration techniques, aiong withappiication of chemicais such as citric acid to improve their success, are aiso described. (Quintessence Int1999;30:475-483)

Key words: allogratt, autogenous graft, guided tissue regeneration, keratinized tissue,mucogingivai surgery, root coverage

' iLjfucogingival surgery is defined, according fo tbel iVi Glossary of Periodontal Teims,^ as "a periodontal^urgical procedure to correct defects in the morphol-

y, position, and/or the amount of gingiva." This termas been changed since it was first introduced byiedman^ in the 1950s as surgery designed to correctroblems such as pockets extending apical to theiicogingival junction, malpositioned frenum or muscleachment, and inadequate depth of the vestibule.Qoval of tbe frenum and deepening of the vestibule

to correct these problems because the primaryp, the lack of attached gingiva, was overlooked.. the 1960s, investigators sucb as Bjorn,' Nabers,*

an^ developed mucogingival surgical tech-es such as free gingival grafts to increase tbe zonebratinized tissue. Miller, however, introduced theperiodontal plastic surgery as "surgical proce-used to correct or eliminate anatomic, develop-

nfal, or traumatic deformities of the gingiva andoiar mucosa." This further expanded the objectiveke surgery from creating an adequate zone of at-êd gingiva to root coverage, along with correction

problems such as root sensitivity, esthetic concerns.Eld fhe prevention of root caries. His intention in per-OTming periodontal plastic surgery was to restore the3sf tissue to the cementoenamel junction andffeate a normal, healthy gingival sulcus.

'Assislant Proiessor. Department of Periodonlics, University of Missis-sippi, Sctiooi ot Dentistry, Jackson, Mississippi

! "Professor and Chairman, Department of Periodonlics, Uniuersity ofMississippi. School of Dentistry, Jackson, Mississippi.

^Reprint requests; Dr Aineza Haeri, Assistant Professor, Department ot" S i c s , University of Mississippi, Schooi of Dentistry, 3500 Nortfi State

et, RcomD307, Jackson, Mississippi 39216-4505 Fax:601-984-6130.

INDICATIONS FOR INCREASING THE ZONEOF KERATINIZED TISSUE

How much keratinized tissue is adequate?

As mentioned, for decades the goal of mucogingivalsurgical procedures was to gain keratinized tissue inareas with tnucogingival problems. The primary objec-tive was to widen the zone of attacbed gingiva to im-prove periodontai healtb. In tbe past, many held sucha philosophy without detemiining how much kera-tinized tissue, if any, was required to achieve health. Inthe 1970s, Lang and Loe' conducted studies to estab-lish a relationship between tbe width of keratinizedtissue and bcalth. They concluded that a rninimum of2 mm of keratinized tissue is necessary to achievehealth. Despite effective oral hygiene, areas wifh lessthan 2 mm of keratinized tissue exhibited persistent in-flamtnation. However, observations by Dorfman et al*indicated that less than 1 mm of attached gingiva isadequate when inflammation is under control. Theyemphasized that therapy should be directed at control-ling the bacterial plaque and reducing inflatnmation.An increase in the band of keratinized tissue is indi-cated in areas of persistent attachment loss. The workof other researchers''"'-^ confirmed this conclusion.

Importance of keratinized tissue inrestorative and orthodontic treatment

The width of keratinized fissue for teeth involving sub-gingival restorative margins has been of concern tosotne investigators. Donaldson'^ emphasized the propercontouring of provisional crowns. Physiologic contourappears to cause less recession than poorly contouredcrowns. He also noted that such crowns must have

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proper margins to avoid exertion of pressure on the sur-rounding tissue. Maynard and Wilson'-' stated that atleast 3 mm of attached gingiva is required if restorativemargins are to he placed in the gingival crevice. Theyalso mentioned that the thicloiess of the keratinized tis-sue is adequate when a periodontal probe cannot heseen through the margin of the free gingiva. Other in-vestigators'''* have confirmed that subgingival restora-tions with a narrow zone of keratinized tissue favor gin-gival recession and inflamtnation. Stetler and Bissada'"proposed a minimum of 2 mm of attached gingiva whenmargins are to be placed subgingivally.

Orthodontic movement of teeth is another concern inareas with minimal attached gingiva. Batenhorst et al"observed formation of alveolar dehiscences on the facialsurfaces of the mandibular incisors in monkeys as teethwere moved facially and occlusally. Resorption of the ce-mentum and dentin was also observed with facial ortho-dontic movement. Steiner et al,'" in another study onmonkeys, discovered significant recession of the gingivalmargin as teeth were orthodontically moved labially.

Maynard and Wilson"' recommended that muco-gingival surgery be performed prior to orthodontictreatment when there is a lack of keratinized tissueand there is demonstrable stress from the frenum onthe margin. Other situations, such as eruption of themandibular incisors labial to adjacent teeth, warrantmucogingival surgery. Maynard,^" in a retrospectivestudy of patients with mucogingival probletns in needof orthodontic therapy, reemphasized the need formucogingival surgery prior to orthodontic therapy tostabilize the attachment levels.

Boyd" reviewed and discussed the indications andtiming of mucogingival therapy with respect to ortho-dontic intervention. He suggested early correction ofmucogingival problems, in the absence of malocclu-sion, to prevent further breakdown. However, if a mal-occlusion exists, consultation with the orthodontist isnecessary to discover the nature and direction ofmovement. If there is a mucogingival problem labial toa tooth to be positioned lingually, then the orthodon-tic procedure would be undertaken first. The attachedgingiva must be reevaluated after completion of theorthodontic treatment.

Coatom et aF^ had a different opinion toward theneed for mucogingival therapy on patients with ortho-dontic problems. Their results indicated that a mini-mal width of keratinized tissue (less than 2 mm) iscapable of withstanding the stresses of orthodonticmovements. Orthodontics should precede surgical in-tervention in areas with a prominent root or faciallytipped teeth with at least a minimal width of kera-tinized tissue. In their study, 47% of the teeth had anincrease in the zone of keratinized tissue following or-thodontic therapy. However, in their opinion, a free

gingival graft was necessary prior to orthodontic treat-ment in areas that eompletely lacked keratinized tis-sue. In general, it seems to be the consensus among in-vestigators that a laci< of keratinized tissue warrantsmucogingival surgery prior to orthodontic therapy.

SURGICAL PROCEDURES TOINCREASE KERATINIZED TISSUE

Free gingival graft

Since the 1960s, the free gingival grafting techniquehas been the most predictable and popular method ofincreasing the band of keratinized tissue around teethwith mucogingival defects. Nabers,'' in 1966, oudinedthis technique; he suggested removal of the sulciilarepithelium, leaving the lamina propria intact. An inci-sion at the mucogingival junction was made to exposethe underlying connective tissue. The gingival tissuewas excised from the palate and contoured and suturedin place to the periosteum. The connective tissue of thedonor tissue contacted the connective tissue of the re-cipient area to maintain the blood supply to the graft.The area was covered with rubber dam material, and asurgical dressing was placed to cover the rubber dam,

Others have contributed to advances in free gingivalgraft therapy. Pennel and coworkers" recommendedthe use of a periosteal fenestration to enhance graftstability. Dordick et aF'' evaluated placement of graftsdirectly on bone. After an initiai lag in healing whenplaced directly on bone, grafts placed on both perios-teum and bone looked similar after 3 weeks. They alsoshowed that nonpathologic dehiscences and fenestra-tions could be covered directly with donor tissue.

Modern free gingival grafting technique has beenreviewed by Cohen.^" Advantages of this treatmentremain the high degree of predictabihty, the simplicity,and the possibilities for root coverage. Disadvantagesinclude the necessity of a second operative site, thepotentially compromised blood supply, greater dis-comfort, and possible hemostasis problems, especiallyat the donor site. Preparation is essentially the same aswas outlined by Nabers,-' It is critical that the free gin-gival margin be removed to allow creeping attachmentto occur. Figures la to lc illustrate the free gingivalgraft technique.

Freeze-dried skin andacellular dermal matrix allograft

Donor materials, such as freeze-dried skin, have heenused to eliminate the second surgical site. This mater-ial has been shown to be biologically compatible withthe human oral tissue ^ * and is nonimmunogenic.'"-"'

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Fig la The mandibular central incisor Fig 1b The autogenous graft is suturedexhibits a mucogingival defecl. place over the recipient bed

Fig 1c The 4-weeii postoperativevievu reveals the keratinized tissue cre-ated as weil as partial roct coverage.

Fig 2a The mandibuiar canine and premoiars exhibit mucogingi-vai defects.

Fig 2b An Aiioderm ailcgraft is placed over the recipient bed.

Freeze-dried skin demonstrates no anti-HLA antibodyactivity following its placement in humans.^- This ma-terial has been proven to be as successful as free auto-genous grafts in gaining keratinized tissue."

Recently, an acellular dermal matrix allograft mater-ial (Alloderm, Lifecore Biomédical) was developed asan alternative to autogenous tissue for gingival grafts.This material has been utilized successfully in burn vic-titns since 1992 and for mucogingival surgeries since1994 34 The ailograft is a biocompatible, aceliular con-nective tissue matrix taken from the dermal tissues ofcadavers. The tissue is taken from the tissue bank andprocessed by a method that decellularizes the graftwhile leaving the basement membrane complex andcollagen matrix intact. This method has the advantageof removing the immunogenic target cells while main-taining a structural framework to support fibroblast mi-gration and new vascularization. Each material is fur-te tested to confirm the absence of the immunogeniccells and the presence of the intact matrixes before un-

Fig 2c The v\ew 3 months after surgery reveals an adequateband of keratin i zat ion created with tinis material.

dergoing the viral inactivation step. Once this is ac-complished, the tissue is freeze dried and packaged.

The use of Allodertu resuited in an increase in theband of keratinized tissue with excellent colormatch."'** Alloderm appears to have more shrinkage,as compared with free-gingival graft. This factor is cur-rently under investigation (Figs 2a to 2c).

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INDICATIONS FOR INCREASING ROOT COVERAGE

In addition to being used to increase tbe zone ofattaebed gingiva, mucogingival surgical procedures areaiso used to gain root coverage, Probiems witb estbet-ies, root caries, and at times sensitivity of the exposedroot surface often warrant sucb procedures. In tbeirearly work, Sullivan and Atkins'' predicted possibleroot coverage using conventional free gingival grafts.They found that narrow recession defects have agreater cbance of complete repair than deep, widedefects, Avascularity of the exposed root surfaces isthe primary factor for the lower success in areas withdeep, wide defects,

Miller * redefined a recession and root coverage clas-sification. His classification is based on tbe depth of tberecession in relation to tbe mucogingival ¡unction andthe amount of remaining interproximal bone. Greaterroot coverage is possible when tbe interproximal boneis in a more coronal position, Witb some minor tech-nique modifications, even deep, wide defects can bepredictably covered. Recession defects tbat extend api-cal to tbe mucogingivai junction in tbe presence of in-terproximal bone loss cannot be repaired completely.

SURGICAL PROCEDURES TOATTAIN ROOT COVERAGE

Lateral sliding flap

The lateral positioned flap was first introduced in1956 by Grupe and Warren.^^ They covered theexposed root suriace hy using a sliding flap operation.This was accomplished by removing the epithelial lin-ing around the defect and making a full-tbickness flaparound the adjacent tooth. After making a verticaiineision to free the pedicle, the flap was moved to coverthe defect. A frenectomy was often combined with suchprocedure. Grupe-*" modified tbis tecbnique to retainthe marginai gingiva of the donor site. The tnajor ad-vantage of this procedure is the intact vaseularity of tbedonor tissue. One disadvantage of this procedure is thelimited supply of keratinized tissue at the donor site.

Bahat et aH' introdueed the transpositional flap tech-nique to overcome the problem of lack of keratinizedtissue of the donor site. Tbey made 2 vertical releasingincisions at tbe line angles of the adjacent teeth andthen raised a fuli-thickness flap. They fheri slid the inter-dental papilla of the adjacent teetb to cover the defect.

Cohen's atlas" outlines the lateral pedicie flap tech-nique quite clearly. Several caveats must be remem-bered. The procedure is contraindieated in areas withdeep interproximal poekets, severe interproximal boneloss, or excessive root prominence or where deep or

extensive root abrasion or erosion exists. Tension onthe flap after it is positioned should not be excessive.The pedicle height should not be excessive withrespect to its width. Tbc graft needs a wide base toensure proper perfusion of tbe coronal extent of theflap. Bone sbould never be left exposed over a rootsurface. Tbis will lead to bone loss and recession atthe donor site.

Coronally positioned flap

Another procedure to gain root coverage is the coro-nally repositioned flap (Figs 3a to 3c). Restrepo'''made a full-tbiekness flap to tbe vestibular fornixalong with 2 vertical releasing incisions. The flap waspositioned coronally to cover the root surface. Hefound that problems such as a reduction of thevestibular depth following surgery are of short dura-tion and that the depth will revert back to normaldepth with muscie function, Allen and Miller" used asplit-thickness flap instead of a full-tbiekness flap intheir technique. Approximately 84% of tbe sites hadcomplete root coverage, Tbe mean percentage in cov-ering tbe denuded roots was 98%.

A 2-step procedure was introduced to increase thezone of keratinized tissue prior to coronal positioningof the fiap,"'^ First, a free gingival graft was placed apicalto the denuded area to gain keratinized tissue. After 2months of healing, coronal repositioning of the flapwas performed for root coverage. Maynard-"' preferredtbe 2-step procedure over the lateral sliding flap be-cause handling areas that involved thin adjacent gin-giva during surgery made root coverage less pre-dictable. He stated several criteria for success of the2-step technique, including reduction of any rootprominence, adequate release of the flap, healing time,interproximal bone crests to be at nonnal height, pres-ence of sballow crevices interproximally, and tissueheight to be witbin 1 mm of tbe cementoenamel june-tion on adjacent tectb,

MatteH^ evaluated the 2-step technique and discov-ered 65% root coverage on a predictable basis,Guinard and Caffesse'" compared the lateral slidingflap and coronally repositioned flap with a free gingi-val graft. They discovered no difference between thetwo regarding tbe gain in root coverage. A mean gainof 2.71 mm of root coverage was discovered 6 monthspos topera tively following botb procedures, which wascomparable to results obtained by Matter.'*^

A semilunar coronally positioned flap to cover thedenuded root surface was introduced by Tarnow. ' Thistechnique has an advantage over tbe other coronallypositioned flap tecbnique because it requires no su-tures. Approximately 2 to 3 mm of root coverage wasobtained with this procedure.

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Fig 3a The patient was concerned aboul ine appearance oí Ihemaxillary an ten OÍ teeth. Fig 3b A full-thickness flap is raised and piaced cotonaliy to

cover the exposed rool surfaces.

Free gingival graft to cover the root surface

The free gingival graft has been utilized to cover theroot surface in addition to increasing keratinized tis-sue. Hoibrook and Ochsenbein-*- evaluated root cover-age with free autogenous grafts in 35 patients. Theydiscovered 95.5°.o total root coverage in reeessions ofless than 3 mm. Success for coverage was reduced to80.6% and 76.6% in areas with recessions of 3 to 5mm and greater than 5 mm, respectively. Total eover-age was achieved in 44''.'(i of the sites. Criteria for suc-cess were (1) elimination of the dead space under thegraft hy proper suturing of the graft to the recipientbed and (2) harvesting of thin grafts (1.5 mm) forrapid revascularization and diffusion of fluids.

Miller * used citric acid treatment prior to placingthe autogenous free gingival graft. Root coverage wasachieved on a predictable hasis using this material.Approximateiy 89.90/0 of the graft sites had completecoverage. In a different study, he outhned factors asso-ciated with failure of free gingival grafts to ohtain rootcoverage.'" These factors were incomplete root plan-ing, faiiure to apply citric aeid following root planing,improper preparation of the recipient site, and im-proper adaptation, size, and thickness. Tolmic et ñVreponed that 72.80/0 of their sites achieved completeroot coverage.

Creeping attachment

Creeping attachment is the result of the coronal migra-tion of the graft margin that occurs up to severai yearsfollowing surgery" (Figs 4a to 4d}. Creeping attachinent's more likely to occur in areas of narrow recession.Matter' obtained an average of 0.89 mm of creeping at-tachment approximately 1 year following surgery.Factors such as oral hygiene and tooth position are im-portant in gaining attachment by creeping of the gin-

Fig 3c SIX months ioliowing surgery, there is more than 60% rootco ierage on centrai and iateral inciso/s.

giva. Similar results were obtained by Bcil et al " 1 yearpostoperatively. Harris ^ evaluated creeping attaehmentfollowing a connective tissue graft with partial-thicknessdouble pedicle graft. Creeping attachment occurred in95.5''.''ci of the subjects and was approximately 0.8 mm.

Citric acid application

Application of citric acid to improve the success of rootcoverage has been evaluated by many investigators.Register and Burdick, ^ in their histoiogic study ondogs, discovered that application of citrie acid (pH 1,0),applied for 2 minutes on the root surface, induced flapreattachment and cementogenesis. Garrett and cowork-ers" discovered that citric acid treattnent in conjunc-tion with root planing exposed collagen fibrils. Thesefibrils were absent on surfaces that are not root planed.Citric acid also removes the radicular smear layer andopens the dentinal tubules to allow the formation ofnew cementum.'^ In addition, it demineralizes the rootsurface and removes residual endotoxins, thus render-ing the environment favorable for attachment,'*

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Fig 4a Ttie mandibular cento! incisors require a iree gingival Fig 4b A Iree gingivai grafl is placed to create a zone of kera-gratt. linization.

Fig 4c One month following tfie surgery, a wide zone of kera-tinized tissue has been creaied

Fig 4d One year fo:iowing surgery, 3 mm ot creeping attachmerithas oocuired on the right central incisor.

According to iVIiller, * citric acid application is oneof the factors that increases the success of the rootcoverage utilizing free autogenous grafts. Liu andSolt"" discovered significant increase in the amount ofkeratinized tissue after use of citric acid with a 2-stepfree gingival graft followed by a coronally positionedflap. Tolmie et aP' obtained an overall mean root cov-erage of Sô.SO/b using citric acid.

Evaluations by Ibbott et al* ' indicated no differ-ence between the citric acid-treated and the un-treated group. They found no clinical justification fortbe use of citric acid prior to free gingival grafting tocover the denuded roots. Approximately 50% to 60%mean root coverage was obtained in their study. Thiswas confirmed by Bertrand and Dunlap,' ^ who statedthat the success of the root coverage is dependent onthe proper case selection rather tban citric acid ap-plication. They reported 70% coverage for bothgroups.

In general, there seems to be controversy over tbeuse of this material. Although several investigatorshave reported improvements using citric acid, compar-ative studies refute such findings.

Double-papilla repositioned flap

In some cases if the adjacent gingiva and the interden-tal papilla of the tooth with gingival recession arehealthy, then it is possible to slide tfie papilla of iheadjacent teeth from eitber side to cover the defect.This procedure is called the double-papilla reposi-tioned flap. Cohen and Ross" stated the advantages ofdouble-papilla repositioned flap technique over thelateral sliding flap: One benefit is tbe minimal arnountof exposure of the underlying periodontium at thedonor sites. This reduces damage to the tissues, heal-ing time, and postoperative complications. There isless tension of the donor tissue, and there is a greateramount of keratinized tissue at the interdental papil-lary area. They recommended this procedure for areaswith no interproximai destruction.'"

This is a predictable method to achieve root cover-age, according to Harris.^'' However, he placed a con-nective tissue graft to cover the denuded root surfacebefore suturing the papillae over tbe graft. Completeroot coverage was attained in 80% of the cases, withoverall mean root coverage of 97.4%.

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ng5a The mandibular right first premoiar Fig 5b A subepithelial connective tissue Fig 5c Two months following surgery com-estiibits a mucogingival delect with existing gralt is placed on the root surface after piete root coverage is achievedrecession. making a spiit-thickness enveiope llap

Subepithelial connective tissue graft

Langer and Langer ^ described the subepithelial con-nective tissue graft for root coverage. Their criteria forplacing such a gran were the existence of wide reces-sions or multiple root exposures along with inade-quate donor sites for sliding flap surgery. A split-thick-ness nap with vertical incisions was created at therecipient site. The donor tissue was harvested fromthe palate to cover the denuded roots and suturedin place. A periodontal dressing was placed over therecipient area. They reported an increase in root cov-erage that ranged from 2 to 6 mm." The donor sitehealed with less discomfort than did the donor site infree gingival graft. The connective tissue graft was pro-vided with a dual hlood supply from connective tissueon the nondcnuded portion of the root and the con-nective tissue side of the ñap.*^

Raetzke*^ placed the connective tissue graft underthe flap, using the envelope technique to improve tis-sue support and nourishment. An overall mean rootcoverage of SO o was obtained, along with an averagegain of 3,5 mm in tissue keratinization. The procedureis illustrated in Figs 5a to 5c.

Nelson ' developed a mucogingival graft procedurethat consisted of a free connective tissue graft fol-lowed by sliding of the adjacent papillae. Tissue washarvested from the palate with a trapdoor approach,and a full-thickness flap with releasing incisions wasreflected to allow repositioning of the papillae overthe connective tissue. Nelson''' reported lOO /o eover-age in areas with less than 3 mm of recession. Rootswith 4 to 6 mm of recession had 92% coverage, andthere was SS /o coverage in the more advanced situa-tions (7- to 10-mm recessions).

As stated previously, Harris^" reflected a partial-thickness flap, utilizing connective tissue with doublepapilla sliding to cover the graft. He achieved 100%root coverage in 80% of cases. Overall, 97.4% of theroot surface was covered in this study. In a recentstudy, Harris" obtained a mean coverage of 94.8% byutihzing this technique.

Guided tissue regeneration

The principles of guided tissue regeneration have beenapplied to treat recession as well as to promote regen-eration of periodontal osseous defects. Tinti et aF usedexpanded polyietrafluoroethylene (e-PTFE) {Gore-Tex,WL Gore) to treat facial recessions in humans. A íull-thickness flap was reflected to approximately 3 mm api-cal to the bony crest. A partial-thickness flap was madefrom the base oi' the full-thickness flap in the apical di-rection. A semilunar incision was dissected to allowcoronal movement of the flap without creating any ten-sion. The root surface was heavily scaled and flaftenedwith a diamond bur. The membrane was trimmed andplaced to cover the root surface. The flap was coronaiiydisplaced to cover the membrane. Their results indi-cated root coverage that ranged from 28.6% to 75%,

One problem with this technique is the difficulty inproviding adequate space for regeneration and coverageof the membrane. In a different study, titanium-rein-forced e-PTFE was used to create space for regenera-tion between the root surface and the membrane. ^ Useof this membrane resulted in a more predictable, faster,and simpler surgical procedure. The use of a trapezoidalflap and better suturing techniques could eliminate theproblems associated with coronaiiy positioning the flapand maintaining an adequate blood supply.'"

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Bioresorbable membranes have also been utilized forroot coverage of the denuded root surface. Roccuzzo ctaF' evaluated Guidor resorbablc tncmbrane (Guidor)and titanium-reinforced e-PTFE tnembrane for thetreatrnent of human buccal gingival recession. Their re-sults indicated no difference between the 2 rnembranesin the amount of root coverage achieved. Mean rootcoverage of 82.4o/o and 83.2% was obtained for theGuidor and c-PTFE rnembranes, respectively.

Pini Prato et al'- compared a 2-stage free gingivalgraft followed by placement of a coronally positionedflap with e-PTFE. Their findings indicated no differ-ence in the amount of root coverage in both groups.Root coverage of 72.7% and 70.Wo was obtained forthe membrane and the control groups, respectively.However, the root coverage was more successful inareas of shallow recession when the coronally posi-tioned flap (SLS /o) was used than when guided tissueregeneration (63.5''.'o) was employed. In deeper reces-sions, guided tissue regeneration provided better rootcoverage (76.6»'o) than did the control (65.8%).

CONCLUSION

Various mucogingival surgical procedures werereviewed. The objectives, indications, and factors forthe success of these procedures were described, andresults obtained from different studies were discussed.The surgeon must be knowledgeable and up to datewith the literature and reported findings so that he orshe will be able to select the best surgical approach in-dicated for the patient to improve the results andachieve a more predictable outcome.

REFERENCES

1. Glossary of Periodontal Terms (ed 3). Chicago: AmericanAcademy of Periodontology 1992.

2. Friedman N. Mucogingival surgery. Tex Dent J I957;75:358-362.

3. Bjorn H. Free transplantation of gingival propria. SverigeTatidl Tidning 1963:22:684-689.

4. Nabers ]. Free gingival grafts. Periodontics 1966;4;243-245.

5. Cowan A. Sulcus deepening incorporating mucosal graft.JPeriodontol 1965;36:188-192.

6. Miller PD. Regenerative and reconstructive periodontaiplastic surgery. Dent Clin North Am 1988;32 287-306.

7 Lang NP, Loe H. The relationship between the width of ker-atinized gingiva and gingivai health. J Periodontoi I972;43;623-627.

8. Dorfmail HS, Ketinedy JE, Bird WC. Lotigitudinal evaiua-tion of free autogenous gingival autografts, J Cliti Periodon-toi 1980:7:316-324.

9. De Trey E, Bernimoulin J. Influence of free gingival graftson the health of the marginal gingiva. J Clin Periodontoi1980;7:381-393.

10. Hangorsky U, Bissada N. Clinical assessment of free gingi-';'vai graft effectiveness on the maintenance of periodontal-heaith. J Periüdontol 1980:51:274-278.

11. Salkin LM, Freedman AL. Stein MD, Bassiouny M. A longi- 'tudinal study of untreated mucogingival defects. J Peri--odontol 1987:58:164-166. ;

12. Freedman AL, Salkin LM, Stein MD, Green K. A 10 yearlongitudinal study of untreated mucogingival defects. J Peri-odontoi 1992;63:71-72.

13. Donaldson D. The etiologj' of gingival recession associated 'with temporary crowns. J Periodontoi 1974;45:468-471. '-

14. Maynard |G, Wiison RD. Physiologic dimensions of thepcriodontium significant to the restorative dentist. J Peri- 'odontol 1979:50:170-174

15. Ericsson I, Lindhe J. Recession in sites with inadequate widthof the keratinized gingiva. J Chn Periodontoi 1984:11:95-103.

16. Stetler KJ, Bissada NF. Significance of the width of kera-tinized gingiva on the periodontal status of teeth with sub-marginai restorations. J Periodontoi 1987;58.696-70t).

17 Batenhorst KF, Bowers GM, Wiliiams JE. Tissue changes re-sulting from facial tipping and extrusion of incisors in mon-keys. J Periodontoi 1974;45:660-668.

18. Steiner GG, Pearson JK, Ainamo J. Changes of the marginalperiodontium as a result of labial tooth movement in mon-keys. J Periodontoi 1981:52:314-320.

19. Maynard JG, Wilson RD. Diagnosis and management ofmucogingivai probiems in children. Dent Child North Am1980:24:683-703.

20. Maynard JG. The rationale for mucogingival therapy in thechild and adolescent. Int J Periodont Rest Dent 1987:7(1):37-51.

21. Boyd RL. Mueogingival considerations and their relation-ships to orthodontics. J Periodontoi 1978:49:67-76.

22. Coatom GW, Behrents RG, Bissada NF. The width of kera-tinized gingiva during orthodontic treatment: Its significantimpact on per iodontai status. J Periodontoi 1981;52;307-313.

23. Pennel BM, Tabor JC. King KO, Towner JD. Fritz BD,Higgason JD. Free masticatory mucosa graft. J Periodontoi1969:40:162-166.

24. Dordick B, Coslet JG, Seibert JS. Clinical evaluation of freeautogenous grafts placed on alveolar bone. Part I. Clinicaipredictability, J Periodontoi 1976;47:559-567

25. Cohen ES. Atlas of Cosmetic and Reconstructive PeriodontalSurgery, ed 2. Baitimore, MD: Lea & Febiger, 1994:84-98.

26. Yukna RA, Sullivan WM. Evaluation of resultant tissue typefollowing tbe intraoral transplantation of various lyophil-ized soft tissues. J Periodont Res 1978:13:177-184.

27. Carroii PB, Tow HD. Vernino AR. The use of allogenicfreeze-dried skin grafts in the oral environment. Oral Surg1974:37:163.

28. Mishkin DJ. Shelley LR Jr, Neville BW. Histologie study of afreeze-dried skin allograft in a human. A case report.JPeriodontol 1983:54:534-537.

29. Abbott WM. Sell KW. Alteration of histocompatibility andspecies antigens in skin by freeze-drying. Surg Forum 1972;23:282.

30. Abbott WM, Hembree JS. Absence of antigenicity in freeze-dried skin ailografts. Cryobiology 1970:6:416.

31. Yukna RA, Turner DW. Robinson LJ. Variable antigenicityof lyophilized allogenic and lyophilized xenogenic sidn inguinea pigs. Int J Periodont Res 1977; 12:197-203,

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• Haeri/Serio

Í2, Gher ME Jr, Williams |É Jr, Vemino AR, Strong DM, PelleuGB. Evaluation of the immunogenicity of freeze-dried skinallografts in humans. J Periodontoi 1980:51:571-577,

33. Yukna RA, Tow HD, Carrol PB, Vemino AR, Bright RW.Comparative clinieai evaluation of freeze-dried sidn alio-grafts and autogenous gingival grafts in humans. JPeriodontoi 1977:4:191-199.

U. Silverstein LH. Fundamentally changing soft tissue grafting.Dentistry Today 1997:40(3):56-59.

35. Silverstein LH. Calian D P An accllular dermal matrix allo-graft substitute for palatal donor tissue. Postgrad Dent 1996;3:14-21.

36. Shulman J. Clinieai evaluation of an acellular dermal allo-graft for increas ing the zone of a t t ached gingiva. PractPeriodont Aesthet Dent 1996:8:205-208.

57. Suliivan HC, Atkins ]H Free autogenous gingival grafts. I.Principles of successful grafting. Pe r iodon t i c s 1968¡6-121-129.

38. Miller PD. Root coverage using the free soft tissue autograftfoLowing citric acid application. Part 111. A successful andpredictable procedure in areas of deep-wide recession. Int |Periodont Rest Dent I985:5(2):15-37.

59. Grupo HE, Warren RE Repair of gingival defects by a slid-ing tlap operation. ] Periodontoi 1956:27:92-95.

-lO. Grupe HE. Modified technique for the sliding flap opera-tion. ) Periodontoi 1966:37:491-495.

41. Bahat BD, Handclsman M, Gordon |. The transpositionalflap in mucogingival surgery. Int J Periodont Rest Dent1990:10:473-482.

42. Restrepo OJ. Coronally repositioned flap: Report uf foureases. | Periodontoi 1973:44:564-567.

43. Allen EP, Miller PD. Coronal positioning of existing gingiva'Short term results in the treatment of shallow marginal tis-sue recession. ] Periodontoi 1989:60:316-319.

44. Bernimoulin |P , Luscher B, Muh lemann HR, Coronallyrepositioned flap. Clinical evaluation after one year. | Peri-odontoi 1975:45:1-13.

45. Maynard JG. Coronal posit ioning of a previously placedautogenous gingival graft. J Periodontoi 1977;48:151-155.

45. Matter ] Free gingival graft and coronally repositioned flap.J Clin Periodontoi 1979;6:437-442.

47. Guinard EA, Caffesse RG. Treatment of locaiized gingivalrecessions. Part HI. Comparison of results obtained withlateral sliding flap and coronally repositioned flaps. J Peri-odontoi 1978:49:457-461.

48. Tarnow DP. Semilunar coronally repositioned flap, J ClinPeriodontoi 1986:13:182-185.

49. Hoibrook T, Ochsenbein C. Complete coverage of the de-nuded root surface with a one-stage gingival graft Int JPeriodont Rest Dent 1983;3(3):9-27

50. Miller PD. Root coverage with the free gingival graft.Factors associated with incompiete coverage. ) Periodontoi1987;58:674-681.

51. Tolmie PN, Rubins RP, Buck GS, Vagianos V, Lanz JC. Thepredictability of root coverage by way of free gingival auto-grafts and citrie acid application: An evaluation by multipleclinicians. Int J Periodont Rest Denl 1991:11:261-271.

52. Matter j . Free gingivai grafts for the treatment of gingivalrecession. A review of some techniques. J Clin Periodontoi1982:9:103-114.

53. Matter |, Creeping attachment of liee gingival grafts. A five-year follow up study. ) Periodontoi 1980:51:681-685.

54. Bell LA, Valluzzo TA, Garnick ||, Pennell BM. The presenceof "creeping attachment" in human gingiva. J Periodontoi1978:49:513-517

55. Harris RJ, Creeping attachment associated with the connec-tive t issue with par t ia l - th ickness double pedicle graft,I Periodontoi 1997:68:890-899.

56. Register AA, Burdick FA, Accelerated reattachmcnt withcementogenesis to dentin, demineralized in situ. II. Defectrepair, J Periodontoi 1976:47:497-505.

57. Garrett JS, Crigger M, Egelberg J. Effects of citric aeid ondiseased root surfaces. ] Periodont Res 1978;13:155-163.

58. Miiler PD. Root coverage grafting for regeneration andaesthetics. Periodontoi 2000 1993:1:118-127.

59. Tanaka K, O'Leary TJ, Kafrawy AH. The effect of citric acidon retained plaque and eaietilus. ] Periodontoi 1989:60:81-83.

60. Liu WJ, Solt CW, A surgical procedure for the treatment oflocalized gingival recession in coniunclion with root surfacecitric acid conditioning. J Periodontoi 1980:51:505-509.

61. Ibbott CG, Oles RD, Laverty WH. Effects of citric acidtreatment on autogenous free graft coverage of localized re-eession. ) Periodontoi 1985:56:662-665.

62. Bertrand PM. Dunlap RM. Coverage of deep wide gingivalelefts with free gingivai autografts. Root pianing with andwithout citric acid demineralizalion. Int J Periodont RestDent 1988:8(l):65-77

63. Cohen DW. Ross SE. The double papillae repositioned flapin periodontal therapy. J Pedodontoi 1968:39:65-70.

64 Harris JR The connective tissue and partial thickness dou-ble pedicle graft: A predictable method of obtaining rootcoverage. I Periodontoi 1992:63:477-486.

65. Langer B, Langer L Subepithelial connective tissue grafttechnique for root coverage. ] Periodontoi 1985:56:715-720,

66. Raetzi(e PB, Covering localized areas of root e.\posure em-ploying the "enveiope"' technique. ] PeHodontoi 1985:56:397-402.

67. Neison SW. The subpedicle connective tissue graft. A biiam-inar reeonstructive procedure for the coverage of denudedroot surfaces. ] Periodontoi 1987;58:95-102.

68. Tinti C, Vincenzi GP, Cortellini P, Pini Prato G, Clauser C.Guided tissue regeneration in the treatment of human facialrecession, A 12-case report. J Periodontoi 1992;63:554-560.

69. Tinti C, Vincenzi GP. Expanded poiytetrafluorocthylenetitanium-reinforced membranes for regeneration of mueo-gingival recession defects, A 12-case report. J Periodontoi1994:65:1088-1094.

70. Tinti C, Vincenzi GP, Cocchetto R. Guided tissue regenera-tion in mucogingivai surgery. ] Periodontoi 1993:64:1184-1191.

71. Roccuzzo M, Lungo M, Corrente G, Gandolfo S. Com-parative study of a bioresorbable and a nonresorbable mem-brane in the treatment of human buccal reeessions. JPeriodontoi 1996:67:7-14,

72. Pini Prato G, Tinti C, Vineenzi GP, Magnani C, Cortellini P,Clauser C. Guided tissue regeneration versus mucogingivalsurgery in the treatment of human buccal recession. JPeriodontoi 1992;63:919-928.

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