Soft tissue grafting around implants

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SOFT TISSUE ANATOMY & GRAFTING PROCEDURS AROUND

DENTAL IMPLANTS

Importance of soft tissue integration

• Anchorage of the implant to bone

• Soft tissue seal around dental implants, equally

important for long term clinical success

• Understanding of both periodontal and peri-

implant anatomy & biology

Anatomy of periodontal and peri-implant soft tissues

• Periodontal soft tissue anatomy

• Connective tissue attachment below the

alveolar crest

1. PDL fibers

2. Sharpey’s fibers

• Connective tissue attachment above the

alveolar crest

1. Transseptal fibers

2. Dentogingival/dentoperiosteal fibers

3. Circular fibers

• Epithelial tissue attachment

1. Oral epithelium

2. Sulcular epithelium

3. Junctional epithelium

• Vascular supply

• Peri-implant soft tissue anatomy

1. Epithelial tissue attachment

2. Connective tissue attachment

• Splicing of fibers - Alveolar crest to free

gingiva and circular CT fibers running

circumferentially around the implant

NEED & RATIONALE

FOR ATTACHED PERI-IMPLANT

SOFT TISSUES

Comparison of the interface

Difference in vascular supply

PERMUCOSAL SEAL

Choosing between a submerged and

nonsubmerged approach

Peri-implant plastic surgery

• Peri-implant plastic surgery focuses on

harmonizing peri-implant structures by means of

hard tissue engineering and soft tissue

engineering, and includes: bone structure

enhancement; soft tissue enhancement; precision

in implant placement; and quality of the

prosthetic restoration.

SOFT TISSUE GRAFTING IN IMPLANT THERAPY

• 1959 Friedman : Mucogingival surgery

• 1980 : Paradigm shift

• 1988 Miller : Periodontal plastic surgery

• 1996 : Defined as

Surgical procedures performed to prevent or correct

anatomic, developmental, traumatic or disease

induced defects of the gingiva, alveolar mucosa or

bone

Periodontal plastic Procedures

• Augmentation of attached tissues surrounding

natural teeth and implant restorations

• Root and implant abutment coverage

• Correction of mucogingival defects around

implants

• Edentulous ridge augmentation in preparation for

prosthetic rehabilitation with conventional or

implant prosthesis

• Edentulous ridge preservation following tooth

removal in preparation for prosthetic rehabilitation

with conventional or implant prosthesis

• Management of aberrant frenula

• Preservation or reconstruction of interdental or

inter-implant papillae

• Surgical soft tissue sculpting procedures

Oral soft tissue grafting with dental implants

Rationale for soft tissue grafting

• “Adequate zone” of attached tissue

• Withstand potential bacterial and mechanical

challenges

• Maynard and Wilson

• Adequate band of gingival tissues - 5mm around a

natural tooth

• Lack of connective tissue, difference in composition,

vascularity and orientation of connective tissue

surrounding a dental implant – More susceptible to

disease

• Abutment connection, implant level impressions and

implant supported removable prosthesis – disruption of

soft tissue seal, apical migration of tissues and crestal

bone loss

Surgical principles of soft tissue grafting

• Related to preparing the recipient site and those

related to harvesting & securing the donor tissue at

the graft site

• First principle : Recipient site must provide for

graft vascularization

• Second principle : Recipient site must provide a

means for rigid immobilization of the graft tissue

• Third principle : Adequate hemostasis must be

obtained at the recipient site

• Fourth principle : Donor tissue must be large enough

to facilitate immobilization at the recipient site and to

take advantage of the peripheral circulation when root

or abutment coverage is the goal

• Finally adequate graft thickness is essential

1.25mm preferable

Modified palatal roll technique for dental implants

• Abrams 1980

• For deficient edentulous ridges for fixed

maxillary prosthesis

• Scharf and Tarnow 1992

• Modification of Abrams technique : “Trap

door” approach

• Reikie 1995

• Application of trap door modification to enhance

soft tissue contours around dental implant

abutments

• Limited use in maxillary anterior area

• Performed in conjunction with second stage for

submerged & simultaneously with non-submerged

implant placement

Modified roll technique

• Most favorable palatal anatomy : located between

canine and first molar

Cross section of maxillary alveolar ridge Full thickness incisions outline the

underlying CT pedicle

CT pedicle is elevated

CT pedicle is rolled & secured in buccal pouch

Performed simultaneous with nonsubmerged implant placement

Premolar implant site with soft tissue defect on buccal aspect

Elevation of split thickness palatal flap CT pedicle elevated with Adsons forceps

Subperiosteal dissection extended to create buccal pouch with vertical release

CT pedicle adapted after one piece nonsubmerged implant placed

Suturing of vertical incisions (pouch) 3 months post operative

Epithelialized palatal graft technique for dental implants

• Predictable success

• Versatile technique

• “Free gingival graft” : Misnomer

Sullivan et al classified gingival grafts based on their thickness

• Thicker grafts resist functional stresses of

mastication, intracrevicular restorative

procedures and oral hygiene procedures

better than thin grafts

Indications and sequencing

• Absence of attached gingiva at edentulous implant

site : perform grafting 8 to 12 weeks before

implant placement

• Less than 3mm attached tissue and less than 10mm

height of mandible or maxilla

• If adequate gingival tissue exists (3mm) at

implant site, gingival grafting can be

performed at second stage for submerged or

simultaneously with nonsubmerged implant

placement

Contemporary surgical technique

• Recipient-site preparation

1. 1st step to minimize time

2. Outlining with 15C scalpel

3. Horizontal followed by the vertical incisions

4. Sharp dissection

5. Vestibular extension for immobilization

• Donor-site preparation

1. Performed during preoperative examination

2. Palate (common), even edentulous sites used

3. PM – Molar region preferred

4. Tin foil – transfer of exact dimensions

5. Uniform partial thickness harvest

6. Sutured to recipient bed

7. Pressure with moistened saline gauze

• Immobilization of the graft at recipient site

• Close adaptation and rigid immobilization

• Should form butt joint with periphery of recipient

bed to prevent sloughing

• Thin fibrin clot

• Initial nourishment of graft

• Suturing at edges coronally

• Pressure application with moist gauze for 10 mins

• In edentulous mandible : Horizontal incision at

mucogingival junction

• Vertical incision at the midline

Gingival grafting to establish a stable peri-implant soft tissue environment in the edentulous mandible

Gingival grafting at second stage surgery in edentulous mandible

Outlining and harvesting of donor tissue

Gingival grafts have been adapted and secured at recipient site with meticulous suturing

Four and eight weeks post operative

One year post operative

Alloderm

• Alternative to harvesting autogenous epithelialized

palatal grafts (1996)

• Advantages

• Disadvantages

• Two distinct sides identified

• Orientation of the graft on recipient bed

Edentulous ridge with inadequate vestibular depth and thin band of attached tissue

Alloderm in PRP solution followed by suturing at the recipient site

One week post surgery Eight weeks post surgery

Subepithelial connective tissue graft technique for dental implants

• Langer and Calagna 1982

• New approach to anterior cosmetic enhancement

• Versatile pocedure to enhance soft tissue contours

around natural teeth and dental implants

• Open approach

• Closed approach

• Graft harvested internally from the palate resulting

in partial thickness donor site pouch....comfortable

palatal wound

• Advantage of dual blood supply at recipient site

• Less technique sensitive

• Easier to perform

• More predictable and excellent colour match

• Indications and sequencing in implant

therapy

• Reconstruction can be done prior to implant

placement, during osseointegration period, at

abutment connection and at any time during the

recall period

• When a small volume defect in soft tissue contour

identified at implant site

• Most practical to perform subepithelial CT graft at

time of submerged implant placement or prior to

nonsubmerged implant placement

• Recipient site considerations

• First step, minimizes the time between graft harvest

and transfer

• Helps determine precise dimensions of donor tissue

• Open or closed technique

• Recipient site surgery

• Closed approach

• Horizontal incision on mesial & distal of soft

tissue defect just coronal to level of root or

abutment coverage 1mm depth

• Split-thickness dissection beyond MGJ

• Width of recipient site : 3 times that of exposed

root or abutment

• Graft immobilization

• Dimensions should closely match the recipient

pouch

• 4-0 chromic suture : Horizontal mattress suture to

engage apical portion of pouch, engaging the graft

and exiting the pouch apically

• Sling suture for close adaptation of the graft

• Interrupted sutures to close the flap in papillary

areas

Closed approach

• Open approach

• Partial-thickness horizontal and vertical incisions

• Exaggerated curvilinear bevelled incisions outlined

to elevate split-thickness flap

• Goal : maximize the thickness of overlying tissue

flap leaving a thin layer of immobile periosteum

• Graft immobilization

• Dimensions should closely match recipient site

• Sling sutures to secure the graft coronally in

position

• Also secured laterally and apically with additional

sutures

• Next, cover flap secured coronally with interrupted

sutures passing through the papillae

Open approach

Open recipient site Closed recipient siteEasier to perform More difficult to prepare

(blind technique)Allows direct

visualization of dissection for uniform

recipient site

Immobilization of graft is technique sensitive

Facilitates coronal advancement of cover

flap

Contraindicated when vestibular depth is

minimalUse of releasing incisions

sacrifices circulationLimits coronal advancement

May require secondary gingivoplasty

Preserves circulation to area

Superior esthetics

• Donor site considerations

• Dimensions depend on size and shape of patient’s

palate

• Ideal location

• Dual and single incision variations are commonly

used

• Vertical incisions avoided to preserve blood supply

and avoid sloughing

• Protective palatal stent

Donor site surgeryDual incision technique

Full thickness curvilinear incision 3mm apical to marginal gingiva

Second, partial thickness incision 1mm deep defines thickness of donor tissue

Tip of scalpel is reoriented to parallel the surface of palatal tissues and sharp dissection used to create a subepithelial pouch

From within the pouch vertical incisions are made through CT and periosteum to define width of donor tissue

Subperiosteal dissection performed using paddle end of elevator and horizontal incision made at apical extent

Donor tissue consisting of epithelium, CT, fat and periosteum is taken to recipient site and adapted

Collaplug absorbable collagen dressing is used to aid in hemostasis and fill the considerable dead space. Chromic gut suture (4-0) is used for closure of donor

Single incision technique

Full thickness curvilinear incision 3mm apical to PMs

Blade reoriented to parallel the surface of the palate

Conclusion

• This topic provides the basis for successful

application of oral soft tissue grafting in implant

therapy and a clear explanation of indications,

advantages, expected outcomes and limitations of

the most commonly used soft tissue grafting

techniques