P3-OS-CHAPTER 10 BOOK

Ameloblastoma

The most common odontogenic tumor to arise in the lower third molar region.

17-20 yrs. old

What is the ideal age to remove an impacted tooth?

Maxillary third molar

What tooth is commonly impacted in the maxillary arch?

Operculum

It is the soft tissue that overlies a partially erupted impacted lower third molar.

Streptococci

The most common causative bacteria of pericoronitis

The recommended irrigant for pericoronitis is hydrogen peroxide, it doesn't only flush out trapped debris underneath the tissue but they also act to debride due to its foaming action. Other irrigants used are chlorhexidine and iodophors

WHAT IRRIGANT SOLUTION IS USUALLY USED TO IRRIGATE MILD PERICORONITIS?

Ideally, impacted third molar is removed if the roots are at least one third formed. This is because if it is removed earlier than that or when roots are still very short, the tooth crown will just rotate around the socket when the surgeon tries to luxate or elevate the tooth. This will make the procedure difficult because it will be hard to find a correct purchase point to facilitate luxation of the tooth.

WHAT HAPPENS WHEN AN IMPACTED THIRD MOLAR IS REMOVED VERY EARLY BEFORE THE ROOT DEVELOPS?

unerupted tooth around the crown

includes both impacted tooth and tooth that is still in the process of erupting.

Impacted tooth

is defined as a tooth that fails to erupt into the dental arch within the usual range of expected time.

o Adjacent teeth

o Inadequate dental arch length and space

o Dense overlying bone

o Excessive soft tissue

o Genetic abnormality

Reasons why a tooth becomes impacted

-Maxi and mandi third molars

-Maxi canines

-Mandi premolars

The most commonly impacted teeth are:

o Younger patients tolerate the procedure better

o Periodontal healing is fast in younger patients

o Recovery is better

o Bone is less dense

o Root formation is incomplete

Advantages of early removal of impacted teeth:

-Failure of rotation from a mesioangular to vertical direction

-Inadequate space exists due to insufficient length of the jaw

-Insufficient space between the anterior border of the ramus and the distal part of the second molar

Factors that make lower third molars to be impacted:

-Prevention of Periodontal Disease

-Prevention of Dental Caries

-Prevention of Pericoronitis

-Prevention of Root Resorption

-Impacted teeth under a Dental Prosthesis

-Prevention of Odontogenic Cysts and Tumors

-Treatment of Pain of Unexplained Origin

-Prevention of Jaw Fracture

-Facilitation of Orthodontic treatment

-Optimal Periodontal Healing

Indications for removal of impacted teeth

-Extremes of Age

-Compromised Medical Status

-Probable Excessive Damage to Adjacent Structures

Enumerate contraindications for removal of impacted teeth

irrigation and curettage by the dentist

Treatment for mild pericoronitis

administer antibiotic to lessen inflammation. Penicillin is the antibiotic of choice.

Treatment for moderate pericoronitis

should be referred to an oral maxillofacial surgeon for treatment under hospital setting.

Treatment for severe pericoronitis

Moderate Pericoronitis

Pericoronitis with mild facial swelling, mild trismus, low grade fever

Severe Pericoronitis

Pericoronitis with inability to open mouth more than 20mm, temperature greater

than 101.2oF, facial swelling, pain and malaise

remove the impacted lower third molar after the resolution of inflammation

The ultimate treatment of pericoronitis is to.....

Panoramic Radiograph

The radiograph of choice for evaluation of an impacted third molar is the _____

cone beam computed tomography (CBCT)

If roots of the impacted tooth are near or superimposed to the inferior alveolar canal, a ______ radiograph is requested to accurately know the exact position of the root in relation to the inferior alveolar canal.

I. Mesioangular

II. Horizontal

III. Vertical

IV. Distoangular

Enumerate Classification of Impacted Teeth based on Angulation

Classification Based on Angulation

Most commonly used classification, this is determined by the inclination of the long axis of the impacted tooth in relation to the long axis of the adjacent second molar.

Mesioangular

The least difficult impaction, crown is tilted towards the second molar in a mesial direction.

Mesioangular

Most commonly seen type of impaction.

Horizontal

Impacted tooth has a long axis perpendicular to that of the second molar

Horizontal

More difficult to remove than mesioangular impacted tooth

Vertical

Long axis of the impacted tooth is parallel to that of the second molar.

Vertical

Second most common impacted tooth angulation for lower third molars.

Distoangular

Most difficult angulation for removal

Distoangular

The crown of the tooth is tilted in a distal direction away from the second molar.

Classification based on Relationship with the Anterior border of the Ramus

This is also known as the Pell and Gregory classification (1, 2, & 3)

Classification based on Relationship with the Anterior border of the Ramus

Determines the position of the mesiodistal diameter of the crown against the anterior border of the ramus. If the tooth is in mesioangular or horizontal position, the clinician imagines the tooth in a vertical position to know its classification.

Pell & Gregory Class 1

- Lower third molar is positioned anterior to the anterior border of the ramus and has a sufficient space for eruption (if angulation is vertical)

- Easiest to remove

Pell & Gregory Class 2

One half of the mesiodistal diameter of the crown is covered with the ramus.

Pell & Gregory Class 3

- Impacted tooth is completely embedded in the bone of the ramus of the mandible

- The most difficult to remove

Classification based on the Relationship to the Occlusal Plane

- Also known as Pell and Gregory Class A, B and C

- This determined the depth of the impacted tooth in relation to the occlusal plane

Pell & Gregory Class A

Occlusal plane is at the same level as the occlusal plane of the second molar

Pell & Gregory Class B

Occlusal plane of the impacted tooth is between the occlusal plane and the cervical line of the second molar

Pell & Gregory Class C

Impacted tooth is below the cervical line of the second molar and difficult to remove

True

True or False: Morphology of the root plays a role in determining the difficulty of removal of impacted teeth. For easy removal length of root should be one third to two thirds formed

False (easier to remove)

True or False: Fused, conical roots are more difficult to remove compared to widely separated roots

True

True or False: Severely dilacerated roots are prone to fracture and thus difficult to remove

False (is greater)

True or False: It is more difficult to remove an impacted tooth if the mesiodistal diameter of the root is lesser compared to the mesiodistal diameter of the crown

False (narrower pdl space is easier to remove)

True or False: Wider periodontal ligament space is easier to remove than those with narrow periodontal ligament space

True

True or False: If size of sac is wide/large, lesser bone removal is required thus procedure is easier

Younger Patients

Large size follicle is commonly seen in...

True

True or False: Bone seen in younger patients are less dense and flexible which makes surgery easier compared to bone seen older patients (35 years old and above) which are denser and very calcified.

True

True or False: If impacted tooth is in direct contact with the second molar it is difficult to remove compared to an impacted tooth that has a space or gap from the second molar

True

True or False: Close approximation of the roots of the impacted molar to the inferior alveolar nerve makes removal difficult.

CLASSIFICATION SYSTEMS FOR MAXILLARY THIRD MOLAR IMPACTIONS

Basically the same with the classification systems for lower third molar impactions

False (mesioangular is difficult to remove in maxi)

True or False: in terms of angulation for maxillary, the distoangular impacted tooth is more difficult to remove compared to mesioangular impacted tooth because of the need to remove more bone in distoangular positioned tooth

Maxi Impaction Class A

Vertical impaction comprises 63% of all maxillary third molar impaction

Maxi Impaction Class B

Distoangular comprises 25%

Maxi Impaction Class C

Mesioangular accounts for 12% of upper third molar impaction (the most difficult angulation to remove)

Accessibility

The primary factor determining the difficulty of the removal of impacted tooth.

Vertical Impaction

It is the angulation most commonly seen in impacted upper third molars.

They are classified according to its location;

-palatally (Class I) located

-labially (Class II) located.

-transverse position (Class III) sometimes

*where crown is palatally located root is in labial side.

HOW ARE MAXILLARY CANINE IMPACTION CLASSIFIED?

To know whether tooth is bucally or lingually placed, the patient's jaw is view from an occlusal view in the CBCT. If CBCT not available, request for occlusal radiograph.

WHAT RADIOGRAPH IS NEEDED TO KNOW WHETHER AN IMPACTED LOWER THIRD MOLAR IS BUCCALLY OR LINGUALLY LOCATED?

I.Reflection of Adequately-Sized Flaps

II.Removal of Overlying Bone

III.Sectioning of Tooth

IV.Delivery of Sectioned Tooth

V.Wound Closure

GIVE FIVE BASIC STEPS FOR SURGICAL REMOVAL OF IMPACTED TEETH

Enevelope Incision; Envelope Flap;

In removal of impacted teeth, ____ incision and ____ flap are the commonly used incision and flap.

three-cornered flap

If more access on the apical portion is needed for removal of impacted teeth, a ______ flap is reflected.

Lingual Bone

In removal of underlying bone, ____ bone should not be removed because of risk of damaging lingual nerve is high.

Ditching

Bone between the tooth and cortical bone of a cancellous bone is also removed through the process called _____.

Straight elevators are commonly used in this step

Note: No luxation is performed because application of excessive force may lead to

fracture of the bone, tooth and possibly fracture of the mandible itself.

In Delivery of Sectioned tooth, what instrument is used?

Initial Suture; 2-3 Sutures

In wound closure, _____ suture is placed on distal aspect of the second molar. ____ amounts of sutures are enough to reposition flap and attain primary closure.

Anxiety reduction protocol

In patient management, _____ protocol must be applied

6-8 hrs

Use long-acting local anesthetics to give patient a pain-free procedure for ___ hours

Analgesics

are given for 2-3 days postoperatively to relieve pain

True

True or False: Antibiotics are only given if patient has pericoronitis or apical abscess, if patient is healthy or surrounding tissues are not infected, antibiotics are not indicated

Ice Packs

are sometimes recommended for patient comfort and to lessen swelling

Trismus

The surgeon must inform patient of _____ that normally happens after the long procedure.

7-10 days

Trismus will eventually resolve ____ days post op

Bupivacaine

What long-acting local anesthetic is recommended for long procedures such as surgical removal of impacted tooth?

Ditching

This maneuver gives access for elevators to gain purchase points.

Lingual Aspect

In what aspect should bone not be removed during removal of an impacted tooth?

-More bone is removed

-Impacted tooth needs to be sectioned

Give 2 differences of surgical removal of erupted tooth and impacted tooth.