1.
Presented by
K.DURGA PRASAD
INTERN
PERIODONTAL PLASTIC
SURGERY

2.
periodontal plastic surgery," a term originally proposed by Miller in 1993 and broadened to include the
following areas:
• periodontal-prosthetic corrections
• crown lengthening
• socket preservation
• ridge augmentation
• esthetic surgical corrections
• coverage of the denuded root surface
• reconstruction of papillae
INTRODUCTION

3.
“Periodontal plastic surgery” is defined as the surgical
procedures performed to correct or eliminate anatomic,
developmental or traumatic deformities of the gingiva or
alveolar mucosa.

4.
Objectives of periodontal plastic surgical techniques included ……
(1) widening of attached gingiva,
(2) deepening of shallow vestibules,
(3) resection of the aberrant frena

5.
The original rationale for mucogingival surgery was predicated on the
assumption that a minimal width of attached gingiva was required to maintain
optimal gingival health.
A wide, attached gingiva is more protective against the accumulation of plaque
than a narrow or a nonexistent zone.
People who practice good and atraumatic oral hygiene may maintain excellent
gingival health with almost no attached gingiva.
Problems Associated with Attached Gingiva

6.
Widening the attached gingiva accomplishes the following four objectives:
1. enhances plaque removal around the gingival margin
2. improves esthetics
3. reduces inflammation around restored teeth
4. gingival margin binds better around teeth and implants
with attached gingiva.

7.
Problems Associated with Shallow Vestibule
● Gingival recession displaces the gingival margin apically, thus reducing
vestibular depth, which is measured from the gingival margin to the bottom
of the vestibule.
● As indicated previously, with minimal vestibular depth, proper hygiene
procedures are jeopardized.
● The sulcular brushing technique requires the placement of the toothbrush
at the gingival margin, which may not be possible with reduced vestibular
depth.

8.
Problems Associated with Aberrant Frenum
A frenum that encroaches on the margin of the gingiva may
interfere with plaque removal, and the tension on the frenum
may tend to open the sulcus. In such cases, surgical removal of
the frenum is indicated

9.
Techniques to Increase Attached Gingiva
Gingival augmentation apical to the
area of recession.
A graft, either pedicle or free, is
placed on a recipient bed apical to the
recessed gingival margin
Gingival augmentation coronal to the
recession (root coverage).
A graft (either pedicle or free) is placed
covering the denuded root surface.

10.
Gingival Augmentation Apical to Recession
TECHNIQUES
FREE GINGIVAL AUTOGRAFT
FREE CONNECTIVE TISSUE AUTOGRAFT
APICALLY POSITIONED GRAFT

11.
Free Gingival
Autografts
Free gingival graft are used to create a widened zone
of attached gingiva
The Classic Technique
Step 1: Prepare the recipient site.
The purpose of this step is to prepare a firm
connective tissue bed to receive the graft.
The recipient site can be prepared by incising at the
existing mucogingival junction with a No. 15 blade to
the desired depth, blending the incision on both ends
with the existing mucogingival line.
Periosteum should be left covering the bone
A, Before treatment; minimal keratinized gingiva.

12.
● Extend the incisions to approximately
twice the desired width of the attached
gingiva, allowing for 50% contraction of
the graft when healing is complete
● The amount of contraction depends on the
extent to which the recipient site
penetrates the muscle attachments. The
deeper the recipient site, the greater is
the tendency for the muscles to elevate
the graft and reduce the final width of the
attached gingiva. B, Recipient site prepared for free
gingival graft.

13.
● The No. 15 blade is used to incise along the gingival margin to
separate a flap consisting of epithelium and underlying connective
tissue without disturbing the periosteum
● Extend the flap to the depth of the vertical incisions.
● Suture the flap where the apical portion of the free graft will be
located. Three to four independent gut sutures are placed. The
needle is first passed as a superficial mattress suture perpendicular to
the incision and then on the periosteum parallel to the incision.

14.
● Grafts can also be placed directly on bone tissue. For this technique, the
flap should be separated by blunt dissection with a periosteal elevator
● ADVANTAGES
Less swelling
Better haemostasis
Less shrinkage
Less post operative mobility

15.
Step 2: Obtain the graft from
the donor site
● transferring a piece of keratinized gingiva
approximately the size of the recipient
site
● a partial-thickness graft is used. The
palate is the usual site from which the
donor tissue is removed.
● The graft should consist of epithelium and
a thin layer of underlying connective
tissue.
C, Palate will be donor site

16.
● Place the template over the donor site, and make a shallow incision
around it with a No. 15 blade.
● Insert the blade to the desired thickness at one edge of the graft.
● Elevate the edge and hold it with tissue forceps.
● Proper thickness is important for survival of the graft. It should be thin
enough to permit diffusion of fluid from the recipient site
● A graft that is too thin may necrose and expose the recipient site.
● If the graft is too thick, its peripheral layer is jeopardized because of the
excessive tissue that separates it from new circulation and nutrients.

17.
● Thick grafts may also create a deeper wound at the donor site, with
the possibility of injuring major palatal arteries.
● The ideal thickness of a graft is between 1.0 and 1.5 mm.
● After the graft is separated, remove the loose tissue tags from the
undersurface.
● Thin the edge to avoid bulbous marginal and interdental contours.

18.
Step 3:Transfer And
Immobilize The Graft
● Remove The sponge from the recipient site,
re apply it with pressure if necessary until
bleeding is stopped. Remove the excess
clot.A thick clot interferes with
vascularisation of the graft.
● Position the graft and adapt it firmly to the
recipient site. A space between the graft
and the underlying tissue (dead space)
impairs vascularization and jeopardizes the
graft.
● Suture the graft at the lateral borders and
to the periosteum to secure it in position.
The graft must be immobilized. Any
movement interferes with healing.
E, Graft transferred to recipient
site.

19.
● Cover the donor site with a periodontal pack for 1 week and repeat if
necessary. Retention of the pack on the donor site can be a problem.
● If facial attached gingiva was used, the pack may be retained by locking
it through the interproximal spaces onto the lingual surface.
● If there are no open interdental spaces, the pack can be covered by a
plastic stent wired to the teeth.
● A modified Hawley retainer is useful to cover the pack on the palate and
over edentulous ridges.
Step 4: Protect the donor site.

20.
Healing of the Graft
● The success of the graft depends on survival of the connective tissue.
● Fibrous organization of the interface between the graft and the recipient bed occurs
within two to several days.
● The graft is initially maintained by a diffusion of fluid from the host bed, adjacent
gingiva, and alveolar mucosa.
● The fluid is a transudate from the host vessels and provides nutrition and hydration
essential for the initial survival of the transplanted tissue
● During the first day, the connective tissue becomes edematous and disorganized and
undergoes degeneration and lysis of some of its elements.
● As healing progresses, the edema is resolved and degenerated connective tissue is
replaced by new granulation tissue.

21.
● Revascularization of the graft starts by the second or third day.
● Many of the graft vessels degenerate and are replaced by new ones,
and some of these participate in the new circulation.
● The central section of the surface is the last to vascular- ize, but this
is complete by the tenth day
● The epithelium undergoes degeneration and sloughing, with complete
necrosis occurring in some areas.
● It is replaced by epithelium from the borders of the recipient site.

22.
● A thin layer of new epithelium is present by the fourth day, with rete pegs
developing by the seventh day.
● healing of a graft of intermediate thickness (0.75 mm) is complete by 10
weeks; thicker grafts (1.75 mm) may require 16 weeks or longer.
● Functional integration of the graft occurs by the 17th day, but the graft is
morphologically distinguishable from the surrounding tissue for months

23.
Free Connective Tissue Autografts
● It is based on the fact that the connective tissue carries the genetic message
for the overlying epithelium to become keratinized. Therefore only connective
tissue from beneath a keratinized zone can be used as a graft.
● The advantage of this technique is that the donor tissue is obtained from the
undersurface of the palatal flap, which is sutured back in primary closure,
therefore healing is by first intention. The patient has less discomfort
postoperatively at the donor site

24.
● Another advantage of the free connective tissue autograft is that, improved
esthetics can be achieved because of a better color match of the grafted
tissue to the adjacent areas.
A,Lack of keratinized, attached gingiva buccal
to central incisor
.B,Verticalincisionstopreparerecipient site
.B,Vertical incisions to prepare recipient site

25.
C, Recipient site prepared.
D, Palate from which connective tissue will be removed
for donor tissue.

26.
E, Removal of connective tissue
. F, Donor site sutured

27.
. G, Connective tissue for graft.
H, Free connective tissue placed at donor
site.

28.
I, Postoperative healing at 10 days. J, Final healing at 3 months.

29.
Apically Displaced Flap
● This technique uses the apically positioned flap, either partial thickness or full
thickness, to increase the zone of keratinized gingiva.
● The apically displaced flap technique increases the width of the keratinized
gingiva but cannot predictably deepen the vestibule with attached gingiva.
● Adequate vestibular depth must be present before the surgery to allow apical
positioning of the flap

30.
Accomplishments.
● The apically displaced flap technique increases the width of the keratinized
gingiva but cannot predictably deepen the vestibule with attached gingiva.
● The edge of the flap may be located in three positions in relation to the
bone as follow
1. Slightly coronal to the crest of the bone.
2. At the level of the crest.
3. Two millimeters short of the crest

31.
Gingival Augmentation Coronal to Recession (Root Coverage)
classification of recession proposed by Miller…
Class I. Marginal tissue recession does not extend to the mucogingival junction. There is no loss
of bone or soft tissue in the interdental area. This type of recession can be narrow or wide.
Class II. Marginal tissue recession extends to or beyond the mucogingival junction. There is no
loss of bone or soft tissue in the interdental area. This type of recession can be subclassified into
wide and narrow.
Class III. Marginal tissue recession extends to or beyond the mucogingival junction. There is bone
and soft tissue loss interdentally or malpositioning of the tooth.
Class IV Marginal tissue recession extends to or beyond the mucogingival Junction. There is
severe bone and soft tissue loss interdentally or severe tooth malposition.

32.
The following is a list of techniques used for root coverage.
1.free gingival autograft
2.pedicle graft (laterally or horizontally displaced flap)
3.coronally advanced flap; includes semilunar pedicle graft (Tarnow)
4.subepithelial connective tissue graft (Langer)
5.guided tissue regeneration (GTR)
6.pouch and tunnel technique (coronally advanced tunnel technique)

33.
Free Gingival Autograft
The Classic Technique.
Miller applied the classic free gingival autograft described previously with a few
modifications.
Step 1:
Root planing. Root planing is performed with the application of saturated citric acid
for 5 minutes on the root surface.

34.
Step 2:
Prepare the recipient site. Make a horizontal incision in the interdental papillae at right
angles to create a margin against which the graft may have a butt joint with the
incision. Vertical incisions are made at the proximal line angles of adjacent teeth and
the retracted tissue is excised. Maintain an intact periosteum in the apical area
Step 3 :
similar to the classic technique described earlier…

35.
Pedicle Autograft
Laterally (Horizontally) Displaced Pedicle Flap.
The laterally positioned flap can be used to cover
isolated, denuded root surfaces that have adequate
donor tissue laterally.
The following is a step-by-step surgical description :
Step 1: Prepare the recipient site
Epithelium is removed around the denuded root
surface. The exposed connective tissue will be the
recipient site for the laterally displaced flap.
A, Preoperative view, maxillary bicuspid.

36.
Step 2: Prepare the flap.
The periodontium of the donor site
should have a satisfactory width of
attached gingiva and minimal loss of
bone, without dehiscence or
fenestration. A full-thickness or
partial-thickness flap may be used.
With a No. 15 blade, make a vertical
incision from the gingival margin to
outline a flap adjacent to the recipient
site. Incise to the periosteum, and
extend the incision into the oral
mucosa to the level of the base of the
recipient site.
B, Recipient site is prepared by exposing the
connective tissue around the recession.

37.
The flap should be sufficiently
wider than the recipient site to
cover the root and provide a
broad margin for attachment to
the connective tissue border
around the root.
C, Incisions are made at the donor site in
preparation of moving the tissue laterally.

38.
Step 3: Transfer the flap.
Slide the flap laterally onto the
adjacent root; making sure that
it lies flat and firm without
excess tension on the base. Fix
the flap to the adjacent gingiva
and alveolar mucosa with
interrupted sutures .
D, Pedicle flap is sutured in position.

39.
Step 4: Protect the flap
and donor site.
Cover the operative field with
aluminum foil and a soft
periodontal dressing, extend- ing
it interdentally and onto the
lingual surface to secure it.
Remove the dressing and sutures
after 1 week.
E, Post- operative result at 1 year.

40.
Coronally Advanced
Flap.
The purpose of the coronally displaced flap
procedure is to create a split-thickness flap in
the area apical to the denuded root and
position it coronally to cover the root.
Classic Technique
Step 1.
With two vertical incisions, delineate the
flap. These incisions should go beyond the
mucogingival junction. Make a crevicular
incision from the gingival margin to the
bottom of the sulcus. Elevate a
mucoperiosteal flap using careful sharp
dissection.
A, Preoperative view. Note the recession and the
lack of attached gingiva.

41.
Step 2.
Scale and plane the root surface.
Step 3.
Return the flap and suture it at a
level coronal to the
pretreatment position. Cover the
area with a periodontal dressing,
which is removed along with the
sutures after 1 week. B, After placement of a free gingival graft.

42.
C, Three months after placement of the
graft.
D, Flap, including the graft, positioned co
and sutured.
E, Six months later.

43.
Semilunar Flap
Technique
Tarnow has described the
semilunar coronally repositioned
flap to cover isolated denuded root
surfaces.
Step 1.
A semilunar incision is made
following the curvature of the
receded gingival margin and ending
about 2- 3 mm short of the tip of
the papillae.
A, Class 1 recession on the facial surface of the
maxillary right central incisor.

44.
Step 2.
Perform a split-thickness dissection
coronally from the incision and
connect it to an intrasulcular
incision.
Step 3.
The tissue will collapse coronally,
covering the denuded root. It is then
held in its new position for a few
minutes with moist gauze. Many
cases do not require either sutures or
periodontal dressing. This technique
is simple and predictably provides 2-
3 mm of root coverage.
B, A semilunar incision is made and tissue
separated from the underlying bone.

45.
This technique is indicated
where the recession is not
extensive (3 mm) and the facial
gingival biotype is thick. It is
successful for the maxilla,
particularly in covering roots
left exposed by the gingival
margin receding from a
recently placed crown margin.
It is not recommended for the
mandibular dentition. C, Crevicular incision.

46.
D, The flap collapses covering the incision, no
sutures given.
E, Appearance after 7 weeks showing complete
root coverage.

47.
Subepithelial Connective
Tissue Graft (Langer and
Langer)
The subepithelial connective
tissue procedure is indicated for
larger and multiple defects with
good vestibular depth and
gingival thickness to allow a split-
thickness flap to be elevated.
Adjacent to the denuded root
surface, the donor connective
tissue is sandwiched between the
split flap.
A, Preoperative view: recession on
mandibular 1st premolar,

48.
Step 1.
Raise a partial-thickness flap
with a horizontal incision 2 mm
away from the tip of the papilla
and two vertical incisions 1- 2
mm away from the gingival
margin of the adjoining teeth.
These incisions should extend
at least one tooth wider
mesiodistally than the area of
gingival recession. Extend the
flap to the mucobuccal fold.
B, Graft site prepared,

49.
Step 2.
Thoroughly plane the root, reducing
its convexity.
Step 3.
Obtain a connective tissue graft
from the palate by means of a
horizontal incision 5- 6 mm from the
gingival margin of molars and
premolars. The palatal wound is
sutured in a primary closure.
C, Graft placed on the recipient site.

50.
Step 4.
Place the connective tissue on the
denuded root(s).
Suture it with resorbable sutures
to the periosteum.
Step 5.
Cover the graft with the outer
portion of the partial-
thickness flap and suture it
interdentally.
D, Flap replaced and covered over the graft.

51.
Step 6.
Cover the area with dry foil
and surgical dressing. After
7 days, the dressing and sutures
are removed. The esthetic
results are favorable with this
technique since the donor
tissue is connective tissue. The
donor site heals by primary
intention. E, Postoperative view showing complete root
coverage.

52.
Guided Tissue Regeneration
Technique for Root
Coverage
GTR should result in the
reconstruction of the
attachment apparatus, along
with cover- age of the denuded
root surface.
The following is a step-by-step
description of the surgery
A, Marked recession of maxillary left
cuspid.

53.
Step 1.
A full-thickness flap is reflected
to the mucogingival junction,
continuing as a partial-thickness
flap 8 mm apical to the
mucogingival junction.
Step 2.
A membrane is placed over the
denuded root surface and the
adjacent tissue.
B, Vertical incisions made and membrane
placed over recession

54.
Step 3.
A suture is passed through the
portion of the mem-
brane that will cover the bone.
This suture is knotted on the
exterior and tied to bend the
membrane, creating a space
between the root and the
membrane. This space allows for
the growth of tissue beneath the
membrane. . C, Flap sutured over the membrane.

55.
Step 4.
The flap is then positioned
coronally and sutured. Four
weeks later, a small envelope
flap is performed, and the
membrane is carefully removed.
The flap is then again
positioned coronally, to protect
the growing tissue, and sutured.
One week later these sutures
are removed D, Postoperative result. Note complete
coverage of recession.

56.
● Membranes used are
Titanium - reinforced membrane
Resorbable membrane
● GTR technique is better when the recession is
greater than 4.8mm apicoronally.

57.
Pouch and Tunnel Technique
(Coronally Advanced Tunnel
Technique)
To minimize incisions and the
reflection of flaps and to provide
abundant blood supply to the
donor tissue, the placement of
the subepithelial donor
connective tissue into pouches
beneath papillary tunnels allows
for intimate contact of donor
tissue to the recipient site

58.
Effective for the anterior maxillary area in which vestibular depth is adequate
and there is good gingival thickness.
Advantage :
Thickening of the gingival margin after healing. The thicker gingival margin
is stable to allow for the possibility of "creeping reattachment" of the margin.
The use of small, contoured blades enables the surgeon to incise and split
the gingival tissues to create the recipient pouches and tunnels.

59.
Step 1.
Preparation of the patient includes
plaque control instruction and
careful scaling and root planing
several weeks before the surgical
procedure. The patient is
instructed to rinse for 3.0 s with
chlorhexidine gluconate solution
0.12%.
Step 2.
After adequate anesthesia of the
region, the surgical procedure, as
follows, is performed.

60.
Step 3.
Composite material stops are placed at
the contact points (temporary) to
prevent the collapse of the suspended
sutures into the interproximal spaces
before the surgery
Step 4.
Root planing of the exposed root
surfaces is performed using Gracey
curettes.
A, Preoperative view. Note gingival
recession.

61.
Step 5.
Initial sulcular incisions are made
using 15c and 12d blades. Small,
contoured blades (Fig. 50.17) and
mini curettes are used to create the
recipient pouches and tunnels.
Step 6.
On the buccal aspect, an
intrasulcular incision is made around
the necks of the teeth. The incision
is extended to one adjacent tooth
both mesially and distally using a 15c
blade
B, Sulcular incision is made from the mesial
to the facial line angles.

62.
Step 7.
Muscle fibers and any remaining
collagen fibers on the inner aspect
of the flap, which prevent the
buccal gingiva from being moved
coronally, are cut using Gracey
curettes.
Step 8.
The papillae are kept intact and
undermined to maintain their
integrity and carefully released
from the underlying bone

63.
Step 9.
An envelope, full-thickness pouch and
tunnel are created and extended
apically beyond the mucogingival line
by blunt dissection for the insertion of
the free connective tissue graft
through the intrasulcular incision.
Step 10.
The size of the pouch, which includes
the area of the denuded root surface,
is measured so that an equivalent size
donor connective tissue can be
procured from the tuberosity
C, A tunnel is made through the papilla
using a blunt incision.

64.
E, The connective tissue is placed through the papillary tunnel and apically beneath the pouch.

65.
Step 11.
A second surgical site is created to
obtain a connective tissue graft of
adequate size and shape to be placed
at the recipient site.
Step 12.
A mattress suture placed at one end
of the graft is helpful in guiding the
graft through the sulcus and beneath
each interdental papilla. The border
of the tissue is gently
pushed into the pouch and tunnel
using tissue forceps and a packing
instrument.
D, A connective tissue graft is taken from the
palate.

66.
Step 13.
A mattress suture placed on one
end of the graft will help maintain
the graft in position while the
buccal tissue covers the
connective tissue graft. This
connective tissue graft is
anchored to the inner aspect of
the buccal flap in the interdental
papilla area. A vertical mattress
suture is used to hold the
connective tissue in position
beneath the gingiva.
F, The facial gingival margin covers the
connective tissue using horizontal mattress
sutures interdentally.

67.
G, Postoperative view. Note complete root coverage and thickened gingival margin at 3 months.

68.
Techniques to Remove the Frenum
● A frenum is a fold of mucous membrane, usually with enclosed muscle
fibers, that attaches the lips and cheeks to the alveolar mucosa and/or
gingiva and underlying periosteum.
● A frenum becomes a problem if the attachment is too close to the marginal
gingiva. Tension on the frenum may pull the gingival margin away from the
tooth.
● This condition may be conducive to plaque accumulation and inhibit proper
placement of the toothbrush at the gingival margin

69.
FRENECTOMY
Frenectomy is complete removal of the frenum, including its attachment to
underlying bone and may be required in the correction of an abnormal diastema
between the maxillary central incisors.
FRENOTOMY
Frenotomy is the relocation of the frenum, usually in a more apical position.

70.
Step 1.
After anesthetizing the area,
engage the frenum with a
hemostat inserted to the depth
of the vestibule.
Step 2.
Incise along the upper surface of
the hemostat, extending beyond
the tip.
A, Preoperative view of frenum between the two
maxillary central incisors.

71.
Step 3.
Make a similar incision along the
undersurface of the hemostat.
Step 4.
Remove the triangular resected
portion of the frenum with the
hemostat. This exposes the
underlying fibrous attachment to
the bone.

72.
Step 5.
Make a horizontal incision,
separating the fibers and bluntly
dissect to the bone.
Step 6.
If necessary, extend the incisions
laterally and suture the labial
mucosa to the apical periosteum.
A gingival graft or connective
tissue graft is placed over the
wound.
B, Removal of the frenum from both the lip
and gingiva.

73.
Step 7.
Clean the surgical field with gauze
sponges until bleeding stops.
Step 8.
Cover the area with dry aluminum
foil and apply the periodontal
dressing.
C, Site is sutured after it is placed over
the wound.

74.
Step 9.
Remove the dressing after 2 weeks
and redress if necessary. One
month is usually required for the
formation of an intact mucosa
with the frenum attached in its
new position.
D, Postoperative view at 2 weeks

75.
Techniques to Deepen the Vestibule
● The presence of adequate vestibular depth is important for both oral
hygiene and retention of prosthetic appliances.
● The classic clinical studies in the early 1960s by Bohannan indicated that
deepening of the vestibule not involving use of a free gingival graft were
not successful when evaluated years later.

76.
● Predictable deepening of the vestibule can only be accomplished by the
use of free autogenous graft techniques and their variants,
● The important clinical aspect in deepening the vestibule is the proper
preparation of the recipient site.
● The recipient site must be covered by immobile periosteal tissue.
● If there is a lack of periosteal connective tissue, the donor tissue may be
placed over bone.
● The donor tissue may be either free gingival or connective tissue, but it
must be placed over a nonmobile recipient site.

77.
Conclusion…..
● periodontal plastic surgery refers to soft-tissue relationships and
manipulations. In all of these procedures, blood supply is the most significant
concern.
● A major complicating factor is the avascular root surface and many
modifications to existing techniques are used to overcome this.
● Diffusion of fluids is short term and of limited benefit as tissue size increases.
● Thus the formation of a circulation through anastomosis and angiogenesis is
crucial to the survival of these therapeutic procedures.

78.
● The formation of vascularity is based on growth molecules, such as vascular
endothelial growth factor (VEGF) and cellular migration, proliferation, and
differentiation.
● As tissue- engineering techniques improve, the success and predict- ability
of mucogingival surgery should dramatically increase.

79.
REFERENCES
American Academy of Periodontology: American Academy of Periodontology: glossary of
periodontal terms, ed 3, Chicago, 1992, American Academy of Periodontology.
Azzi R, Takei H, Etienne D, et al: Root coverage and papilla reconstruction using autogenous
osseous and connective tissue grafts, Int] Peria Rest Dent 2141- 147, 2001.
Becker BE, Becker W: Use of connective tissue autografts for treatment of mucogingival
problems, Int] Periodont Restor Dent 6:89, 1986.
Carranza FA Jr, Carraro JJ: Mucogingival techniques in periodontal surgery, JPa iodontol
41:294, 1970.
Cortellini P, Clauser C, Pini-Prato GP: Histologic assessment of new attach- ment following the
treatment of a human buccal recession by means of a guided tissue regeneration procedure,]
Periodontol 64:387, 1993.
.