ENDODONTIC SURGERY

POSTGRADUATE DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS

UNDER GUIDANCE OF :-

Prof. Dr Riyaz Farooq (HOD)

Dr Aamir Rashid (Asst. Prof.)Dr Fayaz Ahmed (lecturer)

Presenter- Ashish Choudhary

PG student

Part I: Basics

“Surgery is the first and the highest

division of the healing art, pure in

itself, perpetual in its applicability,

a working product of heaven and

sure of fame on earth" - Sushruta

(400 B.C.)

Introduction

CONTENTS

Instruments & operatory setup

Local anesthesia

Soft tissue access

Hard tissue access

Localized hemostasis

Historical aspects to endodontic

surgery

Classification

Rationale of endodontic surgery

Indications

Contraindications

Anatomic considerations

HISTORICAL ASPECT TO ENDODONTICSURGERY…

A Mandible in Egypt from the 4th dynasty (2900 to 2750BC) contained holes, that could have been made for relief ofpain.

The first recorded endodonticsurgical procedure was the incisionand drainage of an acute endodonticabscess performed by Aetius, a Greekphysician–dentist, over 1,500 years.

Intentional replantation 11th century – Abulcasis 1561 – Pare 1712 – Fauchard 1756 – Pfaff 1768 – Berdmore 1778 – Hunter

1839 – Harris recommended theuse of ‘lancet or sharp, pointedknife’ to puncture the tumour onthe gums

1845 – Hullihan operation or rhizodontropy (making a hole

through the gum, the outer edge of the alveolar process, and the

root of the tooth into the nerve cavity and the opening into the

blood vessels of the nerves)

1843 – Desirabode was the first to report root-end resection laterMagitot follwed him in 1860’s and 1870’s

1880 – Brophy reported root-end resection withimmediate root canal fill and management of theapical filling in a patient with extraoral fistula

Sir G. V. Black

G. V. Black in 1886, Farrar in 1884and Grayston in 1887 also recommendedfor amputation of roots in neglected longterm abscess

1890’s – Carl Partsch, a surgeon turneddentist, from Germany developed root-endresection techniques under chloroform andcocaine anaesthesia

Carl Partsch

1895 – 1900’s: Partsch Iand Partsch II methods

Partsch I method – vertical incision directly over the root and

pack the surgical area with iodoform to stop hemorrhage

(marsupialization)

Partsch II method – complete cyst removal followed by a form

of immediate soft tissue apposition and suturing.

1910 - William Hunter promulgatedthe focal infection theory.

1915 – Neumann provided the first detailedanatomical description of the relationships ofthe mandibular roots to both osseous andneurovascular structures

Sir William Hunter

1926 – Neumann proposed a split thickness flap, which in designis known as the modern day Oschenbein-Luebke flap

1935 – Karl Peter classified the

position of the inferior alveolar

canal relative to the molar root, in

addition to providing descriptive

relationships of the maxillary

sinus and its size and position

relative to the roots of maxillary

teeth.

1958- Messings gun

1960- Digital Optical Microscopes

1950’s- Development of

microsurgery….

1993- MTA as root end filling

material (Torabinezad)

Classifications of Endodontic surgery

1. Root resection or apical curettage following an orthograde

filling, either in one stage or in 2 steps.

2. Orthograde filling during root resection or periapical curettage

3. Root resection & retrograde filling

4. Root resection & retrograde filling following an orthograde

filling( 1 or 2 stage procedure)

GROSSMAN:

INGLE:

Surgical drainage

1. Incision and drainage

2. Cortical trephination(Fistulative surgery)

Replacement surgery (extraction/replantation)

Implant surgery

1. Endodontic implants

2. Root-form osseointegratedimplants

Periradicular surgery

1. Curettage

2. Biopsy

3. Root-end resection

4. Root-end preparation and filling

5. Corrective surgery

1. Perforation repair

a. Mechanical (iatrogenic)

b. Resorptive (internal andexternal)

2. Root resection

3. Hemisection

Cohen and Burns:

Class A Class B Class C

Class D Class E Class F

Periradicular surgery

- Curettage

- Root-end resection

- Root-end preparation

Fistulative surgery

- Incision and Drainage

- Cortical trephination

- Decompression

Corrective surgery

- Perforative repair

- Periodontal management

- Intentional replantation

Gutmann: Weine:

Periapical surgery

Curettage,

apicoectomy and

retrograde filling.

Surgery for root

fractures

Amputational surgery

Incision for drainage

Apical surgery

Corrective surgery

Root amputation,

hemisection, bicuspidization

Walton:

Rationale for surgical endodontic treatment !!!!

Nowdays, multiple treatment planning options are available for

root treated teeth that develop recurrent periapical pathosis or have

periapical lesions that fail to heal following adequate root canal

treatment.

“Surgery is always the second best. If you can do something

else, its better”

- John Kirklin

Non surgical retreatment or surgical intervention???

success of endodontic therapy ranges from 53 to 98% when

performed the first time, while that for retreatment cases with

periapical lesion is lowerScand J Dent Res 1979;87:217–24. J Endod 2004;30:1– 4.

Int Endod J 1998;31:155– 60.

Endod Topics 2003;6:114 –34.

Nair PN.

GOOD ENDO !!!

POOR ENDO !!!

Go for surgricalintervention

Specific indications for periradicular surgery today

Ingle; 6th edition

Failure of nonsurgical retreatment (treatment has been

rendered at least two times)

Failure of nonsurgical (initial) treatment and retreatment is

not possible or practical or would not achieve a better result, or

When a biopsy is necessary

“ It is paramount that these indications must be in the best interests ofpatient, within the skills of clinician, and reflective of biological pinciplesof endodontic therapy”

What about Resurgery???

35.7% healed successfully after resurgery,

26.3% healed with uncertain results and

38% did not heal at the one-year follow-up.

J. Peterson & J. L. Gutmann

International Endodontic Journal, 34, 169–175, 2001

Reasons for failure:

Unsatisfactory preparation at the apical end

Advancing marginal periodontitis

Coronal leakage through faulty restorations

Anatomic aberrations that were not addressed during surgery

Iatrogenic damage to tooth or periodontium

Nonsurgicalintervention alone isNEVER an option here

INDICATIONS

Need for surgical drainage

Failed nonsurgical endodontic treatment

1. Irretrievable root canal filling material

2. Irretrievable intraradicular post

3. Calcific metamorphosis of the pulp space

4. Procedural errors

Instrument fragmentation

Non-negotiable ledging

Root perforation

Symptomatic overfilling

5. Anatomic variations

Root dilaceration

Apical root fenestration

Biopsy

Corrective surgery

1. Root resorptive defects

2. Root caries

3. Root resection

4. Hemisection

5. Bicuspidization

Replacement surgery

A. Replacement surgery

1. Intentional replantation(extraction/replantation)

2. Post-traumatic

B. Implant surgery

1. Endodontic

2. Osseointegrated

Need for surgical drainage

Surgical drainage is indicated when purulent and/or hemorrhagic exudate formswithin the soft tissue or the alveolar bone as a result of a symptomatic peri-radicular abscess.

Surgical drainage may be accomplished by

(1) Incision and drainage (I &D) of the soft tissue or

(2) Trephination of the alveolar cortical plate.

An incision should be made through the focal point of the localized swelling torelieve pressure, eliminate exudate and toxins, and stimulate healing.

Cortical trephination is a procedure involving the perforation of the corticalplate to accomplish the release of pressure from the accumulation of exudatewithin the alveolar bone.

Apical trephination involves penetration of the apical foramen with a smallendodontic file and enlarging the apical opening to a size No. 20 or No. 25 file toallow drainage from the periradicular lesion into the canal space.

Fig. Incision & drainage through drain

Cortical

trephination

Apical

trephination

Failed nonsurgical endodontic treatment

Result from incomplete removal of intracanal irritants &lack of complete obturation.

Persistently enlarging or newly developing radiolucenciesassociated with previously filled canals are a sign offailure.

Anatomic variations

Calcificmetamorphosis Canal aberrations Lateral canals

Apical delta

Internal & Externalresorption

Procedural errors

Instrument separartion Nonnegotiatable ledges

Symptomatic overfilling

Procedural errors

Overinstrument & apicalfracture

Rooot perforations

Root fractures

Biopsy

Teeth with vital pulp withmulitilocular radiolucencies

Panoramic radiograph showsthe extent of this lesion

Biospy revealed thepresence of keratocytes

Corrective surgery

Resorptive

defects

Replacement surgery

Close proximity to mentalforamen favours intentionreimplantation

Tooth replanted Tooth extracted

Replacement surgery

Initial RCT Sinus tract persists Symptoms persistedafter retreatment

Atraumatic extraction & apical resection

Replantation completed 3 months follow upNo symptoms

Contraindications

1. Indiscrimate surgery

2. Poor systemic health

3. Psychological impact on the patient

4. Local anatomic factors

Poor Systemic Health

Complete medical history

Patients with such diseases as leukemia or neutropenia

in active state, severely diabetic patients, patients who

have recently had heart surgery or cancer surgery & older

ill patients are exceptions.

Consideration should be given to patients on

anticoagulant medicines (eg., Coumadin); radiation

treatment of the jaw; in pregnancy.

Psychological impact

Anxious, frightened

masochistic

Local factors factors which make operation difficult

may also delay healing

surgical inaccessibility short root lengths missing cortical bone

poor bone support proximity to neurovascular bundles, maxillary sinus

Periodontal considerations

Tooth mobility

Periodontal pockets

Anatomic considerations

Posterior Mandible:

Shallow vestibule thick alveolar bone

Mental foramen

average location was 16 mm inferior to thecementoenamel junction (CEJ) of the secondpremolar, although the range was 8 to 21 mm,

Oral Surg Oral Med Oral Pathol Oral Radiol Endod 85:457, 1998.

Mandibular canal

Cone-beam computed tomography (CBCT) imaging can be very useful

Periapical radiographs taken from two verticalangulations, 0 degrees (parallel technique) and −20 degrees, may help

determine the buccolingual position of the canal.

average vertical distance from the superior border ofthe mandibular canal to the distal root apex of themandibular second molar is approximately 3.5 mm.This increases gradually to approximately 6.2 mm forthe mesial root of the mandibular first molar and to 4.7mm for the second premolar

Posterior Maxilla:

Maxillary sinus

Perforation of the sinus during surgery is fairlycommon (10% to 50%)

Int J Oral Maxillofac Surg 28:192, 1999.

Int J Oral Surg 3:386, 1974. J Endod 24:260, 1998.

Even without periradicular pathosis, the distancebetween the root apices of the maxillary posterior teethand the maxillary sinus sometimes is less than 1 mm

Int Endod J 35:127, 2002

Fortunately, perforation of the maxillary sinus rarely results inlong-term postoperative problems

No difference in healing compared with similar surgicalprocedures without sinus exposure.

membrane usually regenerates, and a thin layer of new bone often formsover the root end, although osseous regeneration is less predictable

Dent Clin North Am 41:563, 1997. 549.

If the maxillary sinus is entered during surgery, special care must be takento prevent infected root fragments and debris from entering the sinus. (Telfa

gauze, sutures)

use of orascope or endoscope, in case of displacement of

root tip in sinus

role of vertical releasing incision

Palatal root

reached from either a buccal (transantral) or palatalapproach

Take care of anterior palatine artery whiletaking the palatal approach ligation of the external carotid artery may be

necessary, if artery is severed

An acrylic surgical stent may be fabricated before surgery to assistrepositioning of the flap and help prevent pooling of blood under the flap.

Anterior maxilla & mandible:

access to the root apex in some patients may be unexpectedly difficultbecause of long roots, a shallow vestibule, or lingual inclination of the roots

Surgery of upper centrals: presence of incisive canal & its contents.

Periradicular surgery on mandibular incisors often is more challenging than

expected.

The combination of lingual root inclination, a shallow vestibule, and a

prominent mental protuberance all can increase the degree of difficulty, as can

proximity to adjacent roots and the need for perpendicular root-end resection

and preparation to include a possible missed lingual canal.

PATIENT PREPARATION FOR

SURGERY

Informed Consent Issues Specific to Surgery

patient must be thoroughly advised of the benefits, risks, and othertreatment options and must be given an opportunity to ask questions.

Although the incidence of serious complications related to surgicalprocedures is very low, patients should be advised of any risks unique totheir situation.

Prompt attention to any surgical complications and thorough follow-up are essential from a medicolegal standpoint.

Premedication:

NSAIDs

Administration of an NSAID, either before or up to 30 minutes aftersurgery, enhances postoperative analgesia

The combination of preoperative administration of an NSAID anduse of a long-acting local anesthetic may be particularly helpful forreducing postoperative pain.

Ibuprofen 400 mg provides analgesia approximately equal to thatobtained with morphine 10 mg and significantly greater than that fromcodeine 60 mg, tramadol 100 mg, or acetaminophen 1000 mg

Oral Maxillofac Surg 47:464,1989.

J Am Dent Assoc 108:598,1984.

McQuay H, Moore R: An evidence based resource for pain relief, Oxford, 1998, Oxford University Press.

The analgesic effectiveness of ibuprofen tends to level offat about the 400 mg level (ceiling effect), although a slightincrease in analgesic potential may be expected in doses upto 800 mg.

Antibiotics

Controversial issue!!!

The current best available evidence does not support the routine useof prophylactic antibiotics for periradicular surgery.

Evid Based Dent 7:72, 2006.

For most patients, the risks of indiscriminate antibiotic therapy arebelieved to be greater than the potential benefits.

J Am Dent Assoc 131:366, 2000.

Although routine use of prophylactic antibiotics for periradicularsurgery is not currently recommended, clinical judgment isimportant in determining exceptions to the general rule.

For example, immunocompromised, diabetic patients, may be goodcandidates for prophylactic antibiotic coverage.

Antimicrobial mouthwash

Chlorhexidine gluconate (0.12%) often is recommended as a mouthrinse to reduce the number of surface microorganisms in the surgicalfield, and its use may be continued during the postoperative healingstage. American Dental Association, 2008.

Conscious sedation

either by an orally administered sedative or by nitrous oxide/oxygen

inhalation analgesia, may be useful for patients who are anxious aboutthe surgical procedure or dental treatment in general.

Benzodiazepines with a short half-life are particularly useful

A typical protocol is a single dose at bedtime the evening before theprocedure and a second dose 1 hour before the start of surgery.

In appropriate doses, benzodiazepines and similar drugs may allowfor a more relaxed patient and thus a less stressful surgical experiencefor both patient and surgeon.

INSTRUMENTS AND OPERATORY SETUPLeft to right (left section

of tray): Small round micromirror, medium oval micromirror, handle for microscalpel, scissors, surgical suction tip.Top to bottom(main

section of tray): Carr #1 retractor, Carr #2 retractor, TRH-1 retractor, periosteal elevator, Ruddle R elevator, Ruddle L elevator, Jacquette curette, spoon curette, Scaler, surgical forceps, mouth mirror, periodontal probe.

Basic tray setup for initial surgical access.

Instrument tray for root-end filling and suturing

Left to right (left

section of tray): Two Castroviejo needle holders, Castroviejo scissors, micro tissue forceps

Top to bottom (main

section of tray):

Cement spatula, Feinstein superplugger microexplorer endoexplorer, right &left SuperEBAPlacing & Plugginginstrument, anterior,left & rightmicroburnisher andpluggers small, medium large

Comparison of microsurgical scalpel (top)to #15C surgical blade.Microsurgical scalpels are particularlyuseful for the intrasulcular incision andfor delicate dissection of theinterproximal papillae.

Microcondensers in assorted shapes and sizes for root-end filling.

Comparison of standard #5 mouth mirror to diamond-coatedmicromirrors

Retractors used in periradicular surgery.Top to bottom, EHR-1, ER 2, and ER-1(equivalent to Carr #2 and #1 retractors)

Placement of root end filling material

Teflon sleeve and plugger especiallydesigned for placement of MTA

Messing gun–type syringe

Kit includes a variety of tips for use indifferent areas of the mouth and asingle-use Teflon plunger

Hard plastic blockwith notches ofvarying shapesand sizes

MAGNIFICATION

LOUPES ORASCOPES

DIGITAL

OPERATING

MICROSCOPES

Surgeon, assistant, and patient positioned for initiation of surgery. The patient should be given tinted goggles or some other form of eyeprotection before the procedure is begun.

LOCAL ANESTHESIA FOR

SURGERY

Local anesthetics for periradicular surgeries:

Lidocaine

Rapid onset, Profound anesthesia, Prolonged duration of action, Low toxicity & allergic potential, Excellent diffusion rate

Articaine

increased ability to penetratebone

Bupivacaine

long duration of effect postoperative pain control

Once anesthesia is established, hemostasis in the softtissues can be enhanced by infiltration with anestheticsolutions containing vasoconstrictors (epinephrine) in conc.of 1:50,000 Anesth Pain Control Dent 2:223-226, 1993)

The local anesthetic is first slowly deposited in the buccal root apexarea of the alveolar mucosa at the surgical site and extended two orthree teeth on either side of the site. Usually palatal or lingual infiltration is also required, although thisrequires a much smaller amount of local anesthetic

After the injections for anesthesia, the surgeon should wait at least 10minutes before making the first incision.

because it is composed of loose connective tissue with largeinterstitial spaces which allow painless injections and rapid diffusionthroughout the mucosal tissues.

Why in submucosa why not in gingival

tissues??

To regain loss of anesthesia during surgery….

Providing supplemental infiltration anesthesia is difficult after afull thickness flap has been reflected A supplemental block injection may be useful for mandibular teethand maxillary posterior teeth.

In the maxillary anterior area, a palatal approach tothe anterior middle superior nerve may be helpful

The key to this approach is slow injection of approximately 1 ml oflocal anesthetic in the area of the first and second maxillary premolars,midway between the gingival crest and the palatal midline.

An intraosseous injection also may be used to regain lost anesthesia,but even when it is effective, the area of local anesthesia often is smallerthan desired for a surgical procedure.

As a last resort, the procedure can be terminated short ofcompletion, and the patient can be rescheduled for surgery undersedation or general anesthesia.

SURGICAL ACCESS

Surgeon must have a thorough knowledge of the anatomicstructures in relation to each other, including tooth anatomy.

must be able to visualize the 3D nature of the structures in the softand hard tissue

trauma of the surgical procedure itself must be minimized, whichincludes the preservation of tooth and supporting structures.

Tissue and instruments must be manipulated within a limited space, with the aim of removing diseased tissues and retaining healthy tissues.

Soft-tissue Access

surgeon must take into consideration various anatomic features,such as frenum-muscle attachments, the width of attached gingiva,papillary height and width, bone eminence, and crown margins.

Vertical Incision

Incision should be made parallel to thesupraperiosteal vessels in the attached gingivaand submucosa

No cuts should be made across frenum andmuscle attachments.

incision should be placed directlyover healthy bone. incision should not be placed

superior to a bony eminence.

dental papilla should be included orexcluded but not dissected.

incision should extend from the depth ofthe vestibular sulcus to the midpoint betweenthe dental papilla and the horizontal aspect ofthe buccal gingival sulcus.

Horizontal Incision

This incision extends from the gingival sulcus through the PDL fibers

and terminates at the crestal bone of the alveolar bone proper.

passes in a buccolingual direction adjacent to each tooth of the dental

papilla and includes the midcol region of each dental papilla.

entire dental papilla is completely mobilized.

Intrasulcular incision that includes the dentalpapilla….

Papillary-based incision….

shallow first incision at the base of

the papilla and a second incision

directed to the crestal bone

Submarginal or Ochsenbein-Luebke flap….

Incision must be placed at least 2 mm from the

depth of the gingival sulcus.

To include or exclude dental papilla???

papillary-based incision resulted in rapid recession free healing.

In contrast, complete mobilization of the papilla led to a

marked loss of papillary height.

use of the papillary-based incision in aesthetically sensitive

regions could help prevent papillary recession and surgicalcleft,

or double papilla.

Lancet 1:264, 1966.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod 91:700, 2001.

Flap Design

Full mucoperiosteal flaps

(a) Triangular (one vertical releasing incision)

(b) Rectangular (two vertical releasing incisions)

(c) Trapezoidal (broad-based rectangular)

(d) Horizontal (no vertical releasing incision)

Limited mucoperiosteal flaps

(a) Submarginal curved (semilunar)

(b) Submarginal scalloped rectangular (Luebke-

Ochsenbein)

Triangular flap…

Indications

midroot perforation repair periapical surgery

- posterior area- short roots

Advantages

easily modified- small relaxing incision- additional vertical incision- extension of horizontal components

easily repositioned maintains the integrity of blood supply

Disadvantages

limited accessibiltytension creates on retractiongingival attachment severed

Rectangular flap…Indications

periapical surgery- multiple teeth- large lesions- long or short roots

lateral root repairs

Advantages

maximum access & visibilty reduces retraction tension facilitates repositioning

Disadvantages

reduced blood supply to flapincreased incision & reflection timegingival attachment violated- gingival recession- crestal bone loss- may uncover dehiscencesuturing is more difficult

Horizontal flap…

Indications

cervical resorptive defects cervical area perforations periodontal procedures

Advantages

no vertical incision ease of repositioning

Disadvantages

limited access & visibiltiydifficult to reflect & retractpredisposed to streching & tearinggingival attachment violated

Semilunar flap…

Indications

esthetic crowns present trephination

Advantages

reduces incision & reflection time maintains integrity of gingivalattachment eliminates potential crestal bone loss

Disadvantages

limited access & visibiltiypredisposed to streching & tearingtendency for increase hemorhagingcrosses root eminencesmay not include entie lesionrepositioning is difficulthealing is associated with scarring

Ochsenbein-luebke flap…Indications

esthetic crowns present periapical surgery

- anterior region- long roots

wide band of attached gingivaAdvantages

ease in incision & reflection enhanced visibilty & access ease in repositioning maintains integrity ofgingival attachment

Disadvantages

Horizontal component disrupts blood supplyvertical component crosses mucogingival

junctiondifficult to alter if size of lesion misjudged

Clinical case of submarginal flap…..

Periodontal probing Submarginal incision

Flap reflection Flap repositioned & sutured

Tissue Reflection

process of separating the soft tissues (gingiva, mucosa, andperiosteum) from the surface of the alveolar bone.

Concept of “undermining elevation”

allows all of the direct reflective forces to be applied to theperiosteum and the bone.

Tissue Retraction

process of holding in position the

reflected soft tissues.

general principles to be followed….

Retractors should rest on solid cortical bone

firm but light pressure should be used

tearing, puncturing, and crushing of the soft tissue should be avoided;

sterile physiologic saline should be used periodically to maintain

hydration of the reflected tissue;

retractor should be large enough to protect the retracted soft tissue during

surgical treatment

Grooving technique

Hard-tissue Access

2 biological considerations….

healthy hard tissue must be preserved heat generation during the process must be minimized.

Temperature increases above normal body temperature in osseoustissues are detrimental.

Two critical factors determine the degree of injury:

how long it remains

elevated??

how high the temperature is

increased ??

Temp. rise (°C)

blood flow initially increases>40°C

46 °C for 2 min blood flow stagnates

deactivates alkaline phosphatase

47-50 °C for 1 min reduces bone formation and isassociated with irreversible cellulardamage and fatty cell infiltration

56°C

Scand J Plast Reconstr Surg 18:261, 1984 J Bone Joint Surg Am 54:297, 1972.

Ann Intern Med 67:183, 1967 Lancet 1:264, 1966

Time effect

At temperatures above 109° F (42.5° C), for every 1° C

elevation in temperature, the exposure time for the same biologic

effect decreases by a factor of approximately 2.

Temperatures above 117° F (47° C) maintained for 1 minute produce

effects similar to those at 118° F (48° C) applied for 30 seconds.

Temperatures above 127° F (53° C) applied for less than 1 second can

adversely affect osteogenesis

Int J Oral Surg 11:115, 1982. J Prosthet Dent 50:101, 1983.

Acta Orthop Scand 55:629, 1984. Scand J Plast Reconstr Surg 18:261, 1984.

Several factors determine the amount of heat generated during

bone removal, including the shape the bur, the rotational speed,

the use of coolant, and the pressure applied during cutting.

Shape & Composition of the bur

round burgentle brushstroke action

Do not use diamond bur

Use of coolant

If an appropriate irrigant is not used, temperatures can exceed thoseknown to impair bone healing (delayed up to 3 wks) Coolant reach the cutting surface.

Pressure applied during cutting

Temperatures can rise above 212° F (100° C) when excess

pressure is applied during cutting.

A high-speed handpiece that exhaustsair from the base rather than the cuttingend is recommended to reduce the risk ofair embolism

OSTEOTOMY

Sometimes, natural root fenestration is present, or in other cases,the cortical bone may be very thin, and probing with a smallsharp curette will allow penetration of cortical bone.

In presence of dense bone, it is best to approach the

entry level by one of the following methods:

1. Length of the root measured from a well angledradiograph,& transferring it to surgical site withhelp of a sterile ruler.

2. Comparing a radiograph taken of a small piece ofsterilized gutta-percha or lead foil that has beenplaced in a small hole drilled at the approximateroot tip location.

Barnes identified four ways in which the root surface

can be distinguished from the surrounding osseous

tissue:

(1) root structure generally has a yellowish color(2) roots do not bleed when probed(3) root texture is smooth and hard as opposed tothe granular and porous nature of bone, and(4) root is surrounded by the periodontal ligament.Some authors advocate the use of methylene bluedye to aid in the identification of the periodontalligament.

Localized Hemostasis

Appropriate hemostasis during surgery minimizes surgicaltime, surgical blood loss, and postoperative hemorrhage andswelling.

Hemostatic agents, generally aid coagulation by inducing rapiddevelopment of an occlusive clot, either by exerting a physicaltamponade action or by enhancing the clotting mechanism andvasoconstriction (or both).

Preoperative Considerations

Thorough review of the patient’s body systems and medical history

increases

Review of the patient’s medications, both prescribed and over-the-

counter (OTC) drugs, is essential.

The patient’s vital signs (i.e., blood pressure, heart rate, and

respiratory rate) should be assessed.

Anxiety and stress can be alleviated with planning, sedation, and

profound local anesthesia.

Local Hemostatic Agents

Collagen-Based Materials….

achieve hemostasis through stimulation ofplatelet adhesion, platelet aggregation and releasereaction, activation of factor XII (Hagemanfactor),and mechanical tamponade by thestructure that forms at the collagen-blood/woundinterface.

Osseous regeneration in the presence of collagen typically proceedsuneventfully, without a foreign body reaction.

Collagen-based materials can be difficult to apply to the bony cryptbecause they adhere to wet surfaces.

J Oral Maxillofac Surg 50:608, 1992.

SurgicelIt is primarily a physical hemostaticagent which acts as a barrier to bloodand then becomes a sticky mass thatserves as an artificial coagulum.

Surgicel is retained in the surgical wound & healing is retarded,with little evidence of resorption of the material at 120 days.Gelfoam

gelatin-based sponge that is water insoluble andbiologically resorbable Stimulates the intrinsic clotting pathway by promotingplatelet disintegration and the subsequent release ofthromboplastin and thrombin

Bonewax

nonabsorbable product composed of

88% beeswax & 12% isopropyl palmitate

retards bone healing and predisposes the surgical site to infection

Ferric sulfate

necrotizing agent with an extremely low pH. agglutination of blood proteins (forms plugs thatoccludes the capillary orifices) used for osteotomies smaller than 5mm application to wound sites has resulted in tissuenecrosis for up to 2 weeks, differences in the degreeof epidermal maturation, and tattoo formation

Hemihydrate Medical -grade calcium sulphate (CS) acts as ahemostatic agent by mechanically blocking open vessels

It is resorbed by body in 2-3 weeks

CS pellet is left in bony cavity, where it acts as a barrier to fastergrowing soft tissues & may aid in bone regeneration by providingmatrix for osteoblasts: Bone inductive agent.

Used for osteotomies larger than 5mm

Epinephrine pellets

sympathomimetic-amine vasoconstrictor,

Racemic epinephrine cotton pellets (Racellet #3;

Pascal Co, Bellevue, WA) contain an average of 0.55mg of racemic epinephrine hydrochloride perpellet, half of which is the pharmacologically activeL-form.

Mechanism

of action

Cautery/Electrosurgery

Cautery stops the flow of blood through coagulation of blood

and tissue protein, leaving an eschar that the body attempts to

slough.

The effect of cautery in the bony crypt during periradicular surgery

has not been studied to date

The detrimental effect of applying heat to bone is proportional to

both temperature and the duration of application.