PERIODONTAL LIGAMENT

CONTENTS Introduction
 Definition
 Extent and shape
 Development
 Structure
 Principle fibers
 Functions of pdl
 Age changes in pdl
 Endo-perio relationships
 EFFECTS OF PULPAL DISEASE ON PERIODONTIUM
 INFLUENCE OF ENDODONTIC PROCEDURES ON PERIODONTIUM
 Clinical aspects of PDL
 PDL injection
 Conclusion
 References

• The normal periodontium is a unique and a complex
dynamic structure; each of its components having distinct
functions that are capable of adaptation during the life of
the structure.
• PDL is the soft, richly vascular and cellular connective
tissue which surrounds the roots of teeth and joins the root
cementum with the socket wall.
• Synonyms: Desmodont, Gomphosis, Pericementum, Dental
–periosteum, Alveolodental ligament, Periodontal
membrane.
INTRODUCTION

• Periodontal ligament is composed of soft complex vascular
and highly cellular connective tissue that surrounds the
tooth roots and connects to the inner wall of the alveolar
bone (Mc Culloch CA, Lekic P, Mc Kee MD Periodontol
2000 24:56,2000)
• It is that soft, specialized CT situated between the
cementum covering the root of the tooth and bone forming
the socket wall. (A.R.Tencate 1971)
DEFINITION

• In the coronal direction it is continuous with lamina propria of gingiva & is
demarcated by the alveolar crest fibers.
• At the root apex it merges with the dental pulp.
• PDL has the shape of an hour glass and is narrowest at the mid root level.
• It ranges in width from 0.15-0.38mm.
EXTENT & SHAPE

WIDTH OF THE PERIODONTAL LIGAMENT:
IT RANGES FROM 0.15-0.21 MM.
THE NARROWEST AREA IS AT THE MID-ROOT ( FULCRUM ). THE REGION
AT THE ALVEOLAR CREST IS THE WIDEST AREA FOLLOWED BY THE APICAL
REGION.
DentinBone
The width generally reduced in:
•Non-functional teeth.
•Un-erupted teeth.
While increased in:
*Teeth subjected to an occlusal
stress within the physiological
limits .
*Deciduous teeth

WIDENED PERIODONTAL LIGAMENT
SPACE
• Definition: Increased width of
periodontal ligament space occurs
due to inflammation. The normal
width of a periodontal ligament
space should be 0.5 mm
• Radiographic Features:
• Edge: Well-defined & Radiolucent
• Shape: Periodontal ligament space
still maintains shape of root

PDL SPACE RADIOGRAPHIC
APPEARANCE
• Thin radiolucent line interposed between the root &
laminadura.
• Occlusal Trauma → widened PDL space or funneling of
coronal aspect of PDL space.
• It can also widened in case of vertical fractures &
progressive systemic sclerosis (Scleroderma).

DEVELOPMENT OF PERIODONTAL
LIGAMENT
 Enamel organ is surrounded by a condensation of ecto mesenchymal cells called
dental sac.
 The part of the dental sac immediately close to the enamel organ is called dental
follicle. (3)
 Once the Hertwig Epithelial root sheath disintegrates leaving behind the Epithelial
rests of Malassez, cells of the dental follicle come close to the surface of newly
formed dentin.
 The dental follicle cells then differentiate into cementoblasts & lay down cementum
on dentin on the developing root.
 The other cells of the dental follicle differentiate into fibroblast & lay down fibers &
ground substance of the periodontal ligament.

 As the crown approaches the oral mucosa during tooth eruption, these
fibroblast become active & start producing collagen fibrils. They initially lack
orientation, but they soon acquire an orientation oblique to the tooth.(4)
 The first collagen bundles appear in the region immediately apical to the
cemento enamel junction & give rise to gingivodental fiber groups. As tooth
eruption progresses, additional oblique fibers appear & become attached to the
newly formed cementum & bone.

• CELLULAR ELEMENTS
a. Connective tissue cells
Synthetic Resorptive
-Fibroblasts - Fibroblasts
-Cementoblasts - Cementoclasts
-Osteoblasts - Osteoclasts
b. Epithelial cell rests
c. Neuro-vascular elements
• PERIODONTAL FIBERS
• GROUND SUBSTANCE
STRUCTURE

CONNECTIVE TISSUE CELLS
 FIBROBLASTS:
 Most predominant cell type of periodontal ligament.
-> found between the fibers of the periodontal ligament, where they are
surrounded by fibers & ground substance.
 Ovoid or elongated cells oriented along the principal fibres.
 Large cells with an extensive cytoplasm
 Associated with protein synthesis & secretion (e.g. RER, several Golgi
complex, & many secretary vesicles)
 Because of exceptionally high rate of turnover of collagen in the ligament,
any interference in the fibroblast function by disease rapidly produces a loss
of the tooth’s supporting tissue.

OSTEOBLASTS
 Found on the surface of the alveolar bone .
 Seen on surfaces of bone giving an epithelium like appearance. Shape
varies (seen as oral, triangular, cuboidal) etc.
 Cytoplasm is basophilic ( because of abundant rough endoplasmic
reticulum)
 Responsible for laying down the organic matrix of bone including the
collagen fibers. Alkaline phosphatase present in osteoblasts is responsible
for its mineralization(13)
 Maintain the integrity of the lacunae and canaliculi.
 Open the channels for diffusion of nutrition through the bone.
 Play a role in removal or deposition of matrix and of calcium when required.

CEMENTOBLASTS
 These are the cells responsible for secreting the organic matrix (mainly
collagen) of cementum.
 As distinct layer of cells on the root surface, similar to osteoblastic layer but
not regular in arrangement.
 Differs from periodontal ligament fibroblasts in->
 Appear near the cementum.
 Less rough Endoplasmic Recticulum
 More Mitochondria(15)

FIBROBLASTS Most common cells in PDL
• Appear as ovoid or elongated cells oriented along the principal fibers, exhibiting pseudopodia
like processes

Cementoblasts Osteoblasts
Both are rich in alkaline phosphatase activity.
ELECTRON MICROGRAPH – OSTEOBLAST –
CROSS SECTION-

Resorptive Cells of PDL
• osteoclasts
• cementoclasts
Both are rich in acid phosphatase
activity.

RESORPTIVE CELLS
OSTEOCLASTS
 Bone resorbing cells.
 Present on the surface of bone where it is removed. At such locations the cells
occupy pits called Resorption bays or lacunae of howship.
 Large cells : 20 – 100 µm diameters.
 Numerous nucleus : upto 20 or more
 Cytoplasm : Numerous mitochondria lysosomes
 Osteoclasts are formed by fusion of mononuclear cells arising from bone marrow.
 They do not cover the whole of resorbing surface at any one time, rather they
service a much larger area by demonstrating considerable motility.
 Inhibitor->Osteoprotegrin(16)

CEMENTOCLASTS
 Resemble Osteoclasts.
 Located in howships lacunae.
 Origin unknown but believed to be same as that of Osteoclasts.
 Since constant deposition of cementum occurs, these cells are not seen during
normal functioning of cementum.

PROGENITOR CELLS
• Can undergo mitotic division
• Can differentiate to different
types of cells
• Have small Close faced nucleus
• Very little cytoplasm
• Highest concentrations close to
blood vessels

EPITHELIAL RESTS OF MALLASSEZ
• Remnants of HERS and are formed
close to cementum
• Most numerous in the apical area
& cervical area.
• Their function is not clear but they
could be involved in periodontal
repair and generation .
• Form a lattice work and appear as
either isolated cluster of cells or
interlacing strands. They diminish
in number with age and may
undergo calcification to form
cementicles.

INDIFFERENT FIBER PLEXUS
• Small Collagen fibers in association with the larger
principal collagen fiber
• Run in all directions forming a plexus
• Described by Shackleford, 1971
• Once the tooth has erupted into clinical occlusion
such an intermediate plexus is no longer
demonstrable.

A- THE PRINCIPAL FIBERS:
THEY ARE FORMED OF COLLAGEN BUNDLES,
WHICH ARE WAVY IN COURSE AND ARE
ARRANGED IN THREE GROUPS.
a) Gingival fibers.
b) Transseptal or interdental ligament.
c) Alveolodental ligament which is subdivided
into the following five groups:
1- Alveolar crest group.
2- Horizontal group.
3- Oblique group.
4-Apical group.
5- Interradicular group.

GINGIVAL FIBERS
1- Dento-gingival fibers:
extend from the cervical
cementum into the gingiva.
2- Alveolo-gingival group:
extends from the alveolar
crest into the gingiva.
3- Circular group: a small
group of fibers that encircles
the tooth and interlaces
with the outer fibers.
4- Dento-periosteal fibers:
they extend from the
cementum directed over the
bone crest and then incline
apically between the
periosteum of the alveolar
bone and the gingiva.

Function of gingival fibers:
They form a rigid cuff around the tooth that can add
stability and resist gingival displacement.
*It connects two adjacent
teeth.
*The ligament runs from
the cementum of one
tooth over the crest of the
alveolus to the cementum
of the adjacent tooth.
*Function:
Resists mesial and distal
tooth separation.
b- The transseptal ligament:

THE ALVEOLODENTAL LIGAMENT:
1-Alveolar crest group:
radiate from the crest of the
alveolar process and attach
themselves to the cervical
part of the cementum.
Function: resists vertical and
intrusive forces.
2-Horizontal group:
The fiber bundles run from
the
cementum to the bone at
right
angle to the long axis of the
tooth.
Function: resists horizontal
and tipping forces.

3- Oblique group:
The fiber bundles run obliquely.
Their attachment in the bone is
somewhat coronal (higher)
than the attachment in the
cementum.
The greatest number of fiber
bundles are found in this group.
Function:
*Performs the main support
of the tooth against masticatory
forces.
*Resists vertical and intrusive
forces.
4- Apical group:
The bundles radiate from the
apical region of the root to
the surrounding bone
Function: resists vertical
force.
5- Interradicular group:
The bundles radiate from the
interradicular septum to the
furcation of the multirooted
tooth.
Function: resists vertical
and lateral forces.

The terminal portion of
principal fibers of
periodontal ligament, that
are inserted into cementum
and alveolar bone are called
Sharpey’s fibers.
The number and size of
sharpey’s fibers varies with
functional status of the
tooth.
Sharpey’s Fibers

• BLOOD SUPPLY: Blood supply is derived mainly from : Inferior and
superior alveolar arteries to mand. & max respectively from 3
sources:
• 1. Apical vessels – supply dental pulp
• 2. Transalveolar vessels
• 3. Intraseptal vessels .
Branches of the intraseptal vessels –
perforate the lamina dura & enter the
ligament.
After entering the PDL, perforating rami
anastomose & form a polyhedral network
which surrounds the root like a stocking.
Perforating channels are more abundant in the maxilla than in the mandible, & more
in the posterior than in the anterior teeth.
This dual supply allows the ligament to survive following removal of the root apex
during certain endodontic procedures

NERVE SUPPLY
The nerve follow almost the same course
as the blood vessels.
Ruffini’s endings : • Found around the
root apex.
• Appear dendritic and end in terminal
expansions among the PDL fiber bundles.
Meissner's corpuscles : mid-root, for
tactile perception.
Course apically - pass through the fundus
of the socket or they may pass through
the cribriform plate to empty into larger
channels pursuing intraosseous paths.
Lymphatic drainage
A. Lymph vessels - Follow the course of
blood vessels.

FUNCTIONS OF PDL:
FORMATIVE AND REMODELING FUNCTION : • Cells of the PDL participate in the formation and
resorption of cementum and bone, which occur in - physiologic tooth movement, -
accommodation of the periodontium to occlusal forces - in the repair of injures. • Remodeling :
The 3-D organization of the fiber meshwork is adapted to accommodate for positional changes
of the tooth in its socket or changes in functional state (such as hypofunction). • It relates to
adaptability of PDL tissues. • Both these processes can occur simultaneously and may therefore
be indistinguishable
NUTRITIONAL: • PDL supplies nutrients to the cementum , bone, and gingiva by way of blood
vessels and provides lymphatic drainage. • The PDL contains blood vessels, which provide
anabolites and other substance to the cementum, bone and gingiva. & removes catabolites. IV.
HOMEOSTATIC: • Adaptability to rapidly changing applied forces and its capacity to maintain its
width at constant diameter throughout life. • Its is evident that the cells of PDL have the ability
to resorb and synthesize the extracellular substance of the connective tissue of the ligament ,
alveolar bone and cementum

SENSORY FUNCTION • The PDL is abundantly supplied with sensory nerve fibers capable of the
repair of transmitting tactile, pressure and pain sensations by the trigeminal pathway. • The PDL
provides a most efficient proprioceptive mechanism. • 4 types of neural terminations are seen
1. Free nerve endings –pain(at regular intervals along the length of the root. 2. Ruffini like
mechanoreceptors (apical area) 3. Meissner’s corpuscles - mechanoreceptors (middle 3rd) 4.
Spindle like pressure and vibration endings (apex)
. PHYSICAL FUNCTION : 1) Provision of a soft tissue ‘casing’ to protect the vessels and nerves
from injury by mechanical forces. 2) Transmission of occlusal forces to the bone. 3) Attachment
of the teeth to the bone. 4) Maintainence of the gingival tissues in their proper relationship to
the teeth. 5) Resistance to the impact of occlusal forces (Shock absorption).

EFFECTS OF AGING ON THE
PERIODONTAL LIGAMENT
 Reduction in vascularity, elasticity.
 Decreased number of fibroblasts with more irregular structure
is seen.
 Decreased Collagen synthesis with increasing age.
 Decrease in no. of periodontal fibers. The fiber bundles were
thicker, broader and more highly organized.
 Areas of hyalinization were present.
 Decreased organic matrix production & epithelial cell rests.
 Increased amount of elastic fibers.
 The surfaces of the periodontal alveolar bone were jagged &
uneven & an irregular insertion of fibers were seen.

CLINICAL CONSIDERATIONS
The primary role of the periodontal socket is to support the
tooth in the bony socket .
Inflammatory diseases of the pulp progress to the apical
periodontal ligament and replace its fiber bundles with
granulation tissue .
 This lesion is called a periapical granuloma may contain
epithelial cells that undergo proliferation and produce a cyst .
 Various surgical techniques like Guided Tissue regeneration
are being used for correction of Periodontal destruction .
Guided Tissue regeneration is based on principle that specific
cells contribute to formation of specific tissues.

ENDO PERIO RELATIONSHIP
 Introduction
 The relationship between the periodontium and the pulp
was first discovered by Simring and Goldberg in 1964
 The pulp and periodontium are intimately related &
the simultaneous existence of pulpal problems &
inflammatory periodontal disease can complicate
the diagnosis and treatment planning.
 The tooth, the pulp tissue within it and its supporting
structures should be viewed as one biologic unit. The
interrelationship of these structures influences each
other during health, function and disease.

• What is endodontic lesion?
• IT IS USED TO DENOTE AN
INFLAMMATORY PROCESS IN
THE PERIODONTAL TISSUES
RESULTING FROM NOXIOUS
AGENTS PRESENT IN THE ROOT
CANAL SYSTEM OF THE TOOTH,
USUALLY A ROOT CANAL
INFECTION .
•
• What is periodontal lesion?
• IT IS USED TO DENOTE AN
INFLAMMATORY PROCESS IN
THE PERIODONTAL TISSUE
RESULTING FROM
ACCUMULATION OF DENTAL
PLAQUE ON THE EXTERNAL
TOOTH SURFACE .
•

PATHWAYS CONNECTING ENDODONTIC
AND PERIODONTAL TISSUES
Anatomical pathways:
Apical foramen
Lateral and accessory canals
Dentinal tubules
Non-physiological pathways:
Iatrogenic root canal perforations
Vertical root fractures

CLASSIFICATION OF ENDO- PERIO
LESIONS
I. Based on etiology, diagnosis, treatment and prognosis
(by Simon, 1972)
1. Primary endodontic lesion
2. Primary periodontal lesion
3. Primary endodontic lesion with secondary periodontal
involvement
4. Primary periodontal lesion with secondary endodontic
involvement
5. True combined lesion.

• An acute exacerbation of a chronic apical lesion on a tooth with a necrotic pulp
may drain coronally through the periodontal ligament into the gingival sulcus. This
condition may clinically mimic the presence of a periodontal abscess. In reality,
however, it would be a sinus tract originating from the pulp that opens into the
periodontal ligament. Primary endodontic lesions usually heal following root canal
therapy. The sinus tract extending into the gingival sulcus or furcation area
disappears at an early stage, if the necrotic pulp has been removed and the root
canals are well sealed.
PRIMARY ENDODONTIC LESION

• These lesions are caused primarily by periodontal pathogens. In this process,
chronic periodontitis progresses apically along the root surface. In most cases,
pulpal tests indicate a clinically normal pulpal reaction. There is frequently an
accumulation of plaque and calculus and the presence of deep pockets may be
detected.
PRIMARY PERIODONTAL LESION

1. Primary endodontic lesion with secondary periodontal involvement
2. Primary periodontal disease with secondary endodontic involvement
3. True combined lesion
COMBINED DISEASES

• Primary endodontic lesion with secondary periodontal involvement may also
occur as a result of root perforation during root canal treatment, or where pins and
posts may have been misplaced during restoration of the crown. Symptoms may be
acute, with periodontal abscess formation associated with pain, swelling, pus or
exudates, pocket formation, and tooth mobility. A more chronic response may
occur without pain, and involves the sudden appearance of a pocket with bleeding
on probing or exudation of pus.
PRIMARY ENDODONTIC LESION WITH SECONDARY PERIODONTAL INVOLVEMENT

• The apical progression of a periodontal pocket may continue until the apical
tissues are involved. In this case, the pulp may become necrotic as a result of
infection entering through lateral canals or the apical foramen. In single-rooted
teeth, the prognosis is usually poor. In molar teeth, the prognosis may be better.
Since not all the roots may suffer the same loss of supporting tissue, root resection
can be considered as a treatment alternative.
PRIMARY PERIODONTAL DISEASE WITH SECONDARY ENDODONTIC
INVOLVEMENT

• True combined endodontic periodontal disease occurs less frequently than other
endodontic-periodontal problems. It is formed when an endodontic lesion
progressing coronally joins an infected periodontal pocket progressing apically.The
degree of attachment loss in this type of lesion is invariably large and the prognosis
guarded. This is particularly true in single-rooted teeth. In molar teeth, root
resection can be an alternative treatment. The radiographic appearance of
combined endodontic periodontal disease may be similar to that of a vertically
fractured tooth. If a sinus tract is present, it may be necessary to raise a flap to
determine the etiology of the lesion.
TRUE COMBINED LESION

PRIMARY ENDODONTIC LESION
–
• conventional endodontic
therapy
• PRIMARY ENDODONTIC LESION
WITH SECONDORY
PERIODONTAL INVOLVEMENT –
• endo-perio therapy
PRIMARY PERIODONTAL
LESION -
Guided tissue regeneration
Root amputation and
hemisection
• PRIMARY PERIODONTAL
LESION WITH SECONDARY
ENDO LESION:
• RCT
• Periodontal therapy
• Root amputation
• GTR
• TRUE COMBINED LESION
• Endo therapy
• Perio therapy
• hemisection
• bicuspidization
• Root amputation

EFFECT OF PERIODONTITIS ON THE PULP
Result in atrophic and other degenerative changes like
• reduction in the number of pulp cells,
• dystrophic mineralization,
• fibrosis,
• reparative dentin formation,
• inflammation and
• resorption.
CAUSE:
Disruption of blood flow through the lateral canals
localized areas of coagulation necrosis in the pulp.

EFFECTS OF PULPAL DISEASE
ON PERIODONTIUM
• Bone resorption
• Radiolucency at the apex of the root
• Highly vascularized granulation tissue
infiltrate to varrying degrees by
inflammatory cells
• Neutrophils are present near the
apical foramen
• Plasma cells , macrophages,
lymphocytes in fibroblast are
increased in the periphery of the
lesion
• INFLUENCE OF ENDODONTIC
PROCEDURES ON PERIODONTIUM
• Aggressive removal of PDL and
underlying cementum during interim
endodontic therapy adversely affects
periodontal healing.
• Precautions to be taken when
periodontal therapy to follow
endodontic treatment.
 Induce less mechanical trauma
 Use more biocompatible sealers

Clinical aspects of PDL
Determination of the working length by nonradiographical methods
Apical periodontal sensitivity
Any method of working length determination, based
on the patient’s response to pain, does not meet the
ideal method of determining WL

PERIODONTAL ABSCESS
Localized purulent infection within the tissues adjacent to the periodontal pocket that
may lead to the destruction of periodontal ligament and alveolar bone
Eitology
• Pre-existing deep pockets,
Clinical Features
• Smooth, shiny swelling of the gingiva
• Painful, tender to palpation
• Purulent exudate
• Radiographic features: Radiographs taken with gutta percha cones gently guided
in to the periodontal pocket to site of abscess may provide an ideal regarding the origin
of abscess.
• Radioluceny on lateral surface of the root .
• widening of pdl
• Treatment
• Incision and drainage
• Extraction

PERIAPICALABSCESS
 Also known as Dento-alveolar
Abscess;develops from acute
periodontitis,periapical granuloma
 acute or chronic suppurative process
of dental periapical region
Causes: irritation of periapical tissues
{endo procedures}
Clinical Feature
1.acute inflammation of
apical peridontium
2.tooth is extremely painful
3.slightly extruded from its
socket

 Radiographic Feature
Thickening of pdl space
 Radiolucent area at apex
 Treatment
 Drainage must be established
 Extract the tooth
Root canal therapy

 An acute apical abscess is a severe inflammatory
response to microorganisms or their irritants that have
leached out into the periradicular tissues.
 Radiographic changes
There is a well-defined radiolucent area, as in many
situations an acute apical abscess is an acute
exacerbation of a chronic situation
periodontal ligament space is widened .
 Treatment: Initial treatment of an acute apical abscess
involves removal of the cause as soon as possible.
 Drainage should be established either by opening
the tooth or incision into a related swelling.
 An antibiotic may need to be prescribed,
depending on the patient’s condition.
 Once the acute symptoms have subsided, then root
canal therapy or extraction may be performed.
Acute apical abscess

CHRONIC APICAL ABSCESS
• The chronic apical abscess is some times so painless that is may go undetected form
years until revealed by an x-ray .It is an inflammatory reaction to pulpal infection
and necrosis characterized by gradual onset,little or no discomfort , and the
intermittent discharge of pus through an associated sinus tract.The chronic abscess
may be differentiated from cysts and granulomas by the fact that both cysts and
granulomas have well defined radiolucencies associated with them. The treatment
is Conventional Root canal treatment.

• PERIAPICAL GRANULOMA
• A periapical granuloma is defined as a
growth of granulomatous tissue
continuous with the periodontal
ligament resulting from pulpal death
with diffusion of toxic products in to the
periapical area .In most cases, a
granuloma is symptomless
• Radiographically one sees a well defined
area of rarefaction with some
irregularities , A massive invasion of
pulpal contaminants will result in the
formation of an acute abscess{phoenix
abscess}.
If left untreated, may undergo transformation into an
apical periodontal cyst

EXTERNAL RESORPTION
[A] INFLAMMATORY RESORPTION:
Can be of pulpal or periodontal orgin
Injury to the PDL:Most frequently this occurs when the ligament is torn
such as in avulsion and luxations.
Injury of surface resorption :Damage to the root surface leads to the
surface resorption of the cementum.
Communication to the necrotic pulp tissue or an inflammatory zone
favouring bacteria.
Radiographic Feature: Not so sharp outlined appearances
Out line of the root canal is seen .
• Surface resorption is caused by acute injury to the PDL and the root
surface .It is very common ,self limiting and reversible . If injury is not
repeated ,healing takes palce with new cementum and PDL.

• APICALSCAR
• An apical scar is represented by a periapical granuloma ,cyst or
abscess that heals with scar tissue.Well circumscribed radiolucency
resembling a granuloma
• APEX LOCATORS
• suzki (1942) Reported a device that measured the electrical
resistance between the PDL and the oral mucosa
• Identification of Apex while performing Endodontic surgery by
staining with 1% Methylene blue soaked microtip identifies root apex
by preferentially staining the Periodontal ligament around the root

PERIODONTAL LIGAMENT INJECTION
Provides pulpal and soft-tissue anesthesia in a localized area (one
tooth) of the mandible without producing extensive soft-tissue
(e.g.Tongue and lower lip) anesthesia.
• Without the extensive soft tissue anesthesia, patients may be
concerned that they are not adequately anesthetized.
• Local anesthetic is diffused apically and into the marrow spaces
surrounding the teeth.
Nerves anesthetized – terminal nerve ending at the site of injection
and at the apex of the tooth
• Areas anesthetized – bone, soft tissue, and apical and pulpal
tissues in the area of injection

• PDL Injection Indications
• 1. Pulpal anesthesia of one or
two teeth in a quadrant
• 2. Treatment of isolated teeth in
mandibular quadrants
• 3. Patients for whom residual
soft-tissue anesthesia in
undesirable
• 4. Situations in which regional
block anesthesia is
contraindicated
• 5. As an adjunctive technique
after nerve block
• anesthesia if partial anesthesia is
present
• Contraindications
• 1.Infection or inflammation at
the site of injection
• 2. Primary teeth, when the
permanent tooth bud is
• present
• a. Enamel hypoplasia has been
reported to occur in a
• developing permanent tooth
when a PDL injection was
• administered to the primary
tooth above it
• 3. Patient who requires a
“numb” sensation for
• psychological comfort

• Advantages
• Minimum dose of local
anesthetic necessary to
• achieve anesthesia (0.2 ml per
root)
• 3. An alternative to partially
successful regional
• nerve block anesthesia
• 4. Rapid onset of profound pulpal
and soft-tissue
• anesthesia (30 seconds)
• 5. Less traumatic
• Disadvantages
1.Proper needle placement is
difficult to achieve in some
areas.
• 2. Leakage of local anesthetic
solution into the patient’s
mouth produces an unpleasant
taste
• 3. Excessive pressure or overly
rapid injection may break the
glass cartridge
• 4. A special syringe may be
necessary.

• PDL Injection Technique
• Area of insertion: along the long axis of the tooth to be treated
• Target area: depth of gingival sulcus
• Landmarks : Roots of the tooth ,Periodontal tissues
• Procedure :Stabilize the syringe along the long axis of the root to be
anesthetized With the bevel of needle on the root, advance the
needle apically until resistance is met ,Deposit 0.2 ml of local
anesthetic solution in a minimum of 20 sec
• If tooth is multi-rooted, remove the needle and repeat the procedure
on the other roots

CONCLUSION
To make a correct diagnosis the clinician should have a thorough
understanding and scientific knowledge of these lesions.
• Despite the segmentation of dentistry into the various areas of
specialization, a clinician needs to perform restorative,
endodontic or periodontal therapy, either singly or in
combination.
• Therefore, to achieve the best outcome for these lesions, a
multi-disciplinary approach should be involved.

REFERENCES
• Carranza’s Clinical Periodontology, 10th Edition
• Oral Histology and Embryology by Orban, 11th
edition
• Fundamentals of Periodontics, 2nd Edition, by
Thomas G. Wilson, Kennath S. Kornman
• Tencate oral histology, 5th edition

PERIODONTAL LIGAMENT

More Related Content

What's hot (20)

Similar to PERIODONTAL LIGAMENT (20)

Recently uploaded (20)

PERIODONTAL LIGAMENT