T H E P E R I O D O N T A L F L A P
BDS IV year (2009-10)
Roll no. 01
A periodontal flap is a section of gingiva &/or mucosa
surgically separated from the underlying tissues to provide
visibility of and access to the bone and root surface.
A flap also allows the gingiva to be displaced to a different
location in patients with mucogingival involvement.
Periodontal flaps can be classified as follows –
a) Based on bone exposure after flap reflection
- mucoperiosteal or full thickness flap
- partial thickness or mucosal flap
b) Based on placement of flap after surgery
- displaced flap
- non displaced flap
c) Based on management of papilla
- conventional flap
- papilla preservation flap
1) Full thickness or mucoperiosteal flap-
All the soft tissue, including the periosteum, is reflected to
expose the bone.
Indication- need to view the alveolar bone
2) Partial thickness or mucosal flap-
It includes only the epithelium and a layer of underlying
The bone remains covered by a layer of connective tissue,
including the periosteum.
Also known as split thickness flap.
Indication- when flap is to be positioned apically, laterally
or coronally; or when the operator does not want to expose
A) Based on bone exposure after flap reflection
Fig :A) internal bevel incision to reflect full thickness
flap. B) internal bevel incision to reflect a partial
1) Non – displaced flap
The flap is returned and sutured in its original position.
2) Displaced flap
The flap is placed apically, coronally, or laterally to its original
1) Conventional flap
In this the interdental papilla is split beneath the contact
point of the two approximating teeth to allow reflection of
buccal and lingual flaps.
B ) B a s e d o n f l a p p l a c e m e n t a f t e r s u r g e r y
C ) B a s e d o n m a n a g e m e n t o f p a p i l l a
The incision is usually scalloped to maintain gingival
morphology and retain as much papilla as possible.
1) When the interdental spaces are too narrow, thereby
precluding the possibility of preserving the papilla.
2) When the flap is to be displaced.
Examples- modified Widman flap, the undisplaced flap,
the apically displaced flap, & the flap for reconstructive
2) Papilla preservation flap
In this the entire papilla is incorporated into one of the
flaps by means of crevicular interdental incisions to sever
the connective tissue attachment and a horizontal incision
at the base of the papilla, leaving it connected to one of the
1) When there are open interdental spaces
2) When esthetics is of concern
3) When bone regeneration techniques are attempted.
Dictated by the surgical judgment of the operator.
Depend on the objectives of the procedure.
Factors to be considered in designing the flap are-
1) Degree of access to the underlying bone and root
2) Final position of the flap
3) Preservation of good blood supply to the flap
Two basic flap designs are used -
1. Conventional flap
2. Papilla preservation flap
The incisions for the facial, and the lingual or palatal flap
reach the tip of the interdental papilla or its vicinity,
thereby splitting the papilla into facial half and a lingual
or palatal half.
Fig: flap design for
1 ) C o n v e n t i o n a l f l a p
papilla is preserved ( not split).
The entire surgical procedure should be planned in detail
before the procedure is initiated as detailed planning
allows for a better clinical result.
2 ) P a p i l l a p r e s e r v a t i o n f l a p
There are basically two types of periodontal flap
Horizontal incisions are directed along the margin of the
gingiva in a mesial or a distal direction.
Types of horizontal incisions recommended are-
It is the incision from which the flap is reflected to expose
the underlying bone and root.
1 ) I n t e r n a l b e v e l i n c i s i o n
Objectives of internal bevel incision are -
1. It removes the pocket lining
2. Conserves the relatively uninvolved outer surface of the
gingiva, which when apically positioned, becomes
3. Produces a sharp, thin flap margin for adaptation to the
bone tooth junction.
This incision is also termed as the first incision because it
is the initial incision in the reflection of a periodontal flap.
Also termed as reverse bevel incision because its bevel is in
reverse direction from that of the gingivectomy incision.
Blade used for making this incision - #15C or #15
Fig: Position of the knife in performing internal bevel incision.
The internal bevel incision starts from a designated area
on the gingiva and is directed to an area at or near the
crest of the bone.
It is made from the base of the pocket to the crest of the
The incision together with the initial reverse bevel incision
forms a V- shaped wedge ending at or near the crest of
This wedge of tissue contains most of the inflamed &
granulomatous areas that constitute the lateral wall of the
pocket as well as the junctional epithelium & the
connective tissue fibers that still persist between the bottom
of the pocket & the crest of the bone.
2 ) C r e v i c u l a r i n c i s i o n
Fig : Position of knife in performing crevicular incision.
A periosteal elevator is inserted into the initial internal
bevel incision, & the flap is separated from the bone .
The most apical end of the internal bevel incision is
exposed and visible. With this access, the surgeon is able
to make the interdental incision.
This incision is made to separate the collar of the gingiva
that is left around the tooth.
Knife used for this incision- Orban knife.
3 ) I n t e r d e n t a l i n c i s i o n
The incision is made not only around the facial & the
lingual radicular area but also interdentally, connecting
the facial and the lingual segments to the free the gingiva
completely around the tooth.
Fig : Three incisions necessary for flap surgery. A) internal
bevel incision B) crevicular incision C) interdental
Vertical or oblique releasing incisions can be used on one
or both ends of the horizontal incision, depending on the
purpose & design of the flap.
Vertical incisions at both the ends are necessary if the flap
is to be apically displaced.
Vertical incision must extend beyond the mucogingival
line, reaching the alveolar mucosa, to allow for the release
of the flap to be displaced.
Vertical incisions are avoided in the lingual or palatal
Facial vertical incisions should not be made in the centre
of an interdental papilla or over the radicular surface of a
Fig : The incision
should be made at the
Incisions should be made at the line angles of a tooth
either to include the papilla in the flap or to avoid it
Vertical incisions should also be designed to avoid short
flaps with long, apically directed incisions because this
could jeopardize the blood supply of the flap.
S.no Type of flap Reflection
1) Full thickness
Blunt dissection Periosteal
um from the
2) Partial thickness
flap or mucosal
Sharp dissection Surgical
Fig : Elevation of flap with
periosteal elevator to obtain full
Fig: Elevation of flap with BP
knife to obtain a split thickness
The purpose of suturing is to maintain the flap in the
desired position until healing has progressed to the point
where sutures are no longer needed.
Suture materials for periodontal flap are –
1) Non absorbable •Silk: braided
The resorbable sutures have gained popularity because
they enhance patient comfort & eliminate suture removal
The non resorbable silk braided suture was the most
commonly used in the past due to its ease of use & low
The expanded polytetrafluoroethylene synthetic
monofilament is an excellent nonresorbable suture widely
The most commonly used resorbable sutures are the
natural plain gut or the chromic gut. Both are mono-
filaments and are processed from purified collagen of
either sheep or cattle intestine.
The chromic gut is a plain gut suture processed with
chromic salts to make it resistant to enzymatic resorption,
thereby increasing the resorption time.
1) The needle should enter the tissues at right angles and no
less than 2 to 3 mm from the incision.
2) The needle is then carried through the tissue, following
the needle's curvature.
T e c h n i q u e o r p r i n c i p l e s o f s u t u r i n g
3) The knot should not be placed over the incision.
4) The periodontal flap is closed either with independent
sutures or with continuous, independent sling sutures.
5) Sutures of any type in the interdental papillae should be
placed at a point located below the imaginary line that
forms the base of the triangle of the interdental papilla as
shown in the figure below.
6) The location of sutures for closure of a palatal flap depends
on the extent of flap elevation that has been performed.
The flap is divided in four quadrants as shown in the figure
below. If the elevation of the flap is slight or moderate, the
sutures can be placed in the quadrant closest to the teeth. If
the flap elevation is substantial, the sutures should be
placed in the central quadrants of the palate.
7) The clinician may or may not use periodontal dressings.
When the flaps are not apically displaced, it is not
necessary to use dressings other than for patient comfort.
L i g a t i o n
Direct Loop Suture
permits a better
closure of the interdental
should be performed
when bone grafts are
used or when close
apposition of the
scalloped incision is
there is thread
between the two flaps.
used when the flaps
are not in close
apposition because of
apical flap position or
2) Sling ligation The sling ligation can be used for a flap
on one surface of a tooth that involves two
T y p e s O f S u t u r e s
1) Horizontal mattress
often used for the
interproximal areas of diastema
or for wide interdental spaces
to adapt the interproximal
papilla properly against the
can be incorporated with the
continuous, independent sling
is used when there is both a facial
and a lingual flap involving many
This type of suture does not pull on
the lingual flap when this flap is
is especially appropriate for the
maxillary arch because the palatal
gingiva is attached and fibrous
3) Anchor suture This suture closes the facial and
lingual flaps and adapts them tightly
against the tooth.
Another technique to close a flap
located in an edentulous area
mesial or distal to a tooth.
Consists of tying a direct suture
that closes the proximal flap,
carrying one of the threads around
the tooth to anchor the tissue
against the tooth, and then tying
the two threads.
5) Periosteal suture used to hold the apically
displaced partial-thickness flaps on
It is of two types-
1. holding suture
2. closing suture
FIG: Periosteal sutures for an apically displaced flap. Holding
sutures, shown at the bottom, are done first, followed by the
closing sutures, shown at the coronal edge of the flap.
1. The Holding Suture - is a horizontal mattress suture placed
at the base of the displaced flap to secure it into the new
2. The Closing Suture- are used to secure the flap edges to the
suturing ( up
to 24 hours)
A connection between the flap and the
tooth or bone surface is established which
contains fibrin reticulum with many PMN
leukocytes, erythrocytes, debris of injured
cells, & capillaries at the edge of the
2) 1-3 days
The space between the flap & the tooth or
bone is thinner & epithetlial cells migrate
over the border of the flap, usually
contacting the tooth at this time.
3) One week
An epithelial attachment to the root has been
established by means of hemidesmosomes & a
Blood clot is replaced by granulation tissue
derived from the gingival connective tissue,
the bone marrow, & the PDL.
4) Two weeks
Collagen fibers begin to appear parallel to the
Union of the flap to the tooth is still weak
because of presence of immature collagen
5) One month
A fully epithelialized gingival crevice with a
well defined epithelial attachment is present.
There is beginning of functional arrangement
of supra crestal fibers.