CHAP 3-ODONTECTOMY

Vocabulary flashcards created from the lecture notes on Oral Surgery 2 - ODONTECTOMY.

Dentoalveolar Surgery

Surgical procedures performed most often by oral & maxillofacial surgeons that pertain to the dentate segment of the maxilla or mandible (collectively called the alveolar ridge).

few of dentoalveolar surgery procedures

1. tooth extractions

2. alveoloplasty

3. removal of tori

4. placement of dental implants

5. exposure of impacted teeth for orthodontic treatment

6. extraction of impacted teeth

common complications of dentoalveolar surgery:

1. alveolar osteitis

2. nerve injury

3. displacement of a tooth fragment during surgery

Alveolar Osteitis

Also known as dry socket; described as postoperative pain inside and around the extraction site that increases in severity between the 1st & 3rd day post-extraction, accompanied by a partial of total disintegration of the blood clot within the alveolar socket. (with or without halitosis)

Odontectomy

Surgical removal of a tooth by reflection of a mucoperiosteal flap, excision of surrounding bone, and application of force to remove the tooth from its socket.

ideal timing of the removal of impacted third molars

-the time when the roots of the tooth are 1/3 formed, but just before 2/3 of the roots are formed (Nola’s stage 7&8)

-usually occurs between the middle & late teenage years of an individual (i.e. 17-20 yrs old)

-best done before the presence of any symptoms especially pain

advantages for removing an impacted tooth in younger patients

1. young patients can better tolerate the procedure

2. faster recovery for young patients

3. periodontal healing is better in younger patients

4. more complete regeneration of periodontal tissues located in the distal surface of a second molar (or the tooth that is adjacent to the impacted tooth)

5. better chance of recovery if a nerve was injured during the procedure

factors that may complicate extraction (impacted canines)

1. difficulty in localization (most important factor)

2. close proximity to the roots of the neighboring teeth

3. maxillary sinus approximation

4. abnormal root curvature & morphology

5. hypercementosis

6. patient’s inability to open the mouth widely

Hypercementosis

Excessive development of secondary cementum on the tooth surface, which mainly occurs on the apex of a tooth. (focal & circular(?))

factors that may complicate extraction (impacted maxillary 3rd molars)

1. maxillary sinus approximation (oro-antral communication)

2. 3rd molar is within or above the roots of the maxillary second molar

3. fusion and/or concrescence of roots with the maxillary second molar

4. abnormal root curvature & morphology

5. hypercementosis

6. extreme bone density

7. dental follicular space is filled with bone

8. patient’s inability to open the mouth widely

Fusion

Complete or incomplete union of 2 adjacent normal tooth germs during tooth development, usually resulting in 1 large tooth and 1 less tooth in the dental arch, with two separate root canals.

Concrescence

A type of fusion involving the union of >/$\text{= } 2$ adjoining teeth from cementum deposition alone, occurring only in the root portion.

Gemination

Unsuccessful division of 2 teeth resulting in 2 teeth that share only 1 root canal.

Twinning

Condition wherein 2 separate teeth produced from 1 tooth bud result in 1 extra tooth in the dental arch.

factors that may complicate extraction (impacted mandibular 3rd molars)

1. mandibular canal approximation

2. 3rd molar is within or below the roots of the mandibular 2nd molar

3. fusion and/or concrescence of roots with the mandibular 2nd molar

4. abnormal root curvature & morphology (such as long thin roots or divergent roots)

5. complete bony impaction

6. dense inelastic bone

7. thin dental follicle

8. narrow periodontal ligament space

9. patient’s inability to open the mouth widely

10. increased size or width of the patient’s tongue (macroglossia)

3 Finger Test or using a Boley gauge

A basic diagnostic test or tool used to assess interincisal distance, corresponding to 3 fingerbreadths ($54 - 57\,mm$).

normal lateral movement of the jaws

8-12 mm

causes of inability to open the mouth

1. trismus / jaw hypomobility

2. pseudo-ankylosis

3. false ankylosis

4. true ankylosis

Trismus

-Also known as jaw hypomobility; pertains to limited or restricted range of motion of the jaw or progressive reduction in mouth opening

-characteristic early sign of tetanus.

-often associated with dysphagia (difficulty in mouth swallowing)

trismus can be attributed or caused by the following:

a. odontogenic origin

b. trauma

c. neoplasms

d. neurotoxins

e. psychogenic causes

f. pharmacologic reasons

Lockjaw

The total inability to close or open the mouth depending on the extent of trismus.

Pseudo-Ankylosis

Mechanical interference in the temporomandibular joint (TMJ), such as coronoid process obstruction from a depressed zygomatic arch fracture.

pseudo-ankylosis can be attributed or caused by the following:

a. trauma

b. hyperplasia

c. neoplasms

d. other causes

myositis ossificans

benign ossifying lesion that can affect any type of soft tissue but it is commonly found in a muscle

submucous fibrosis

premalignant lesion characterized with the progressive fibrosis of the submucosal tissue

False Ankylosis

Extracapsular condition resulting from pathological conditions outside of the temporomandibular joint (TMJ), such as periarticular fibrosis or suppurations.

false ankylosis can be attributed or caused by the following:

a. infection

b. trauma

c. neoplasms

d. other causes

True Ankylosis

Intracapsular condition involving fusion of the bony surfaces (condyle and glenoid fossa) of the temporomandibular joint (TMJ).

true ankylosis can be attributed or caused by the following:

a. infection

b. trauma

c. systemic causes

d. neoplasms

e. other causes

types of impaction (based on the nature of the overlying tissues)

1. soft tissue impaction

2. hard tissue impaction / bony impaction

Soft Tissue Impaction

Impaction where insufficient space prevents gums from pulling back for cleaning, and the height of the crown is located above the alveolar bone.

Partial Bony Impaction

Hard tissue impaction where enough space exists for partial eruption, but the height of the crown is below the level of surrounding bone on radiographs.

Complete Bony Impaction

Hard tissue impaction characterized by an absence of space to erupt, with the tooth completely embedded or encased in jaw bone.

chronology of impacted teeth

impacted canines

-occurs in approx. 2% of the general population (8% of which are bilateral impactions)

-twice as common in females

indications for extraction (impacted canines)

1. ankylosed impacted canines

2. canines that cannot be transplanted

3. severely dilacerated roots

4. canine is undergoing external or internal root resorption

5. impaction is severe (canine is lodged between the roots of the central & lateral incisors)

6. occlusion is acceptable with the first premolar located in the position of the canine

7. presence of pathologic changes (e.g. infections of cysts)

8. patient is not planning to undergo orthodontic treatment

Tooth Ankylosis

Solid fixation of a tooth resulting from fusion of the cementum and alveolar bone, with obliteration of the periodontal ligament.

occurs anytime during eruption

Tooth Autotransplantation

Also called autogenous tooth transplantation; surgical procedure used to transplant an embedded, impacted, or erupted tooth from one site to another site or prepared socket in the same individual.

Dilaceration

An angulation, sharp bend, or curve anywhere along the root portion of a tooth, or between the crown and root, altering its axial inclination.

contraindications for extraction (impacted canines)

1. canine can be brought into position through surgery

2. canine can be brought into position through orthodontic treatment

classification of impaction (maxillary canines)

I. according to archer (1975)

II. according to field-ackerman (1935)

III. according to ericson & kurol (1987)

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS I

-palatally impacted canines

a. horizontal

b. vertical

c. semi-vertical

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS II

-labial or buccal located impacted canine

a. horizontal

b. vertical

c. semi-vertical

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS III

-situated both in the palate & in the labial or buccal area

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS IV

-located in the alveolar surface

-usually in a vertical position between the incisors & the first premolar

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS V

-situated in an edentulous maxilla

classification of impaction (maxillary canines)

I. ACCORDING TO ARCHER

CLASS VI

-located in an aberrant or unusual position

classification of impaction (maxillary canines)

I. ACCORDING TO FIELD-ACKERMAN

LABIAL POSITION

I - crown is closely positioned with the incisors

II - crown is well above the apices of the incisors

classification of impaction (maxillary canines)

I. ACCORDING TO FIELD-ACKERMAN

PALATAL POSITION

I - crown is near the surface with close proximity to the roots of incisors

II - deeply embedded crown with close proximity to the apices of the incisors

classification of impaction (maxillary canines)

I. ACCORDING TO FIELD-ACKERMAN

INTERMEDIATE POSITION

I - crown is between the lateral incisors & the roots of the first premolar

II - crown is above the teeth with the crown labially placed & the roots are palatally located

III - crown is above the teeth with the crown palatally placed & the roots are labially located

classification of impaction (maxillary canines)

I. ACCORDING TO FIELD-ACKERMAN

UNUSUAL POSITION

I - located in the nasal or antral wall

II - located in the infraorbital region

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

-uses the cusp tip of the impacted canine in relation to the root of the lateral incisor in order to measure the amount of overlap as viewed on a panoramic radiograph

-linear measurement is made from the cusp tip of the canine to the occlusal plane at a 90degree angle, and the anteroposterior position of the cusp tip is assigned to one of five zones:

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

SECTOR 1

-cusp tip of the canine is located distal to the root of the lateral incisor

-cusp tip of the canine is between the inter-incisor median line & the long axis of the central incisor

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

SECTOR 2

-cusp tip of the canine is located mesial to sector 1, but distal to the midline of the lateral incisor root

-cusp tip of the canine is between the major axis of the central & lateral incisors

-cusp tip pf the canine is overlapped on the distal half of the root of the lateral incisor

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

SECTOR 3

-cusp tip of the canine is located mesial to sector 2, but distal to the mesial outline of the lateral incisor root

-cusp tip of the canine is between the major axis of the lateral incisors & the first premolar

-cusp tip of the canine is overlapped on the mesial half of the root of the lateral incisor

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

SECTOR 4

-cusp tip of the canine is located mesial to the mesial outline of the root of the lateral incisor

-includes all areas mesial to sector 3

-cusp tip of the canine is overlapped on the distal half of the root of the central incisor

classification of impaction (maxillary canines)

I. ACCORDING TO ERICSON & KUROL

SECTOR 5

-cusp tip of the canine is overlapped on the mesial half of the root of the central incisor

classification of impaction (mandibular canines)

I. based on angulation

II. based on depth

III. according to field-ackerman

classification of impaction (mandibular canines)

I. BASED ON ANGULATION

1. mesioangular

2. distoangular

3. vertical

4. horizontal

classification of impaction (mandibular canines)

I. BASED ON ANGULATION

1. mesioangular

tooth is tilted or angled forward, towards the midline or front of the mouth

classification of impaction (mandibular canines)

I. BASED ON ANGULATION

2. distoangular

tooth is tilted or angled backward, away from the midline & facing the rear of the mouth

classification of impaction (mandibular canines)

I. BASED ON ANGULATION

3. vertical

tooth forms upright at a right (90degree) angle in which the long axis of the tooth is parallel (or almost parallel) to the long axis of the adjacent tooth

classification of impaction (mandibular canines)

I. BASED ON ANGULATION

4. horizontal

tooth forms upright at a right (90degree) angle in which the long axis of the tooth is perpendicular (or almost perpendicular) to the long axis of the adjacent tooth

classification of impaction (mandibular canines)

I. BASED ON DEPTH

1. LEVEL A

2. LEVEL B

3. LEVEL C

classification of impaction (mandibular canines)

II. BASED ON DEPTH

1. LEVEL A

cusp tip of the crown is at the cervical line of the adjacent tooth

classification of impaction (mandibular canines)

II. BASED ON DEPTH

2. LEVEL B

cusp tip of the crown is between the cervical line & root apices of the adjacent teeth

classification of impaction (mandibular canines)

II. BASED ON DEPTH

3. LEVEL C

cusp tip of the crown is beneath the root apices of the adjacent teeth

classification of impaction (mandibular canines)

III. ACCORDING TO FIELD-ACKERMAN

A. labial position

classification of impaction (mandibular canines)

III. ACCORDING TO FIELD-ACKERMAN

1. LABIAL POSITION

A. vertical

B. oblique

C. horizontal

Prophylactic Space Augmentation

Interceptive procedure eliminating crowding in the dental arch to generate space for the eruption of impacted canines.

Guided Eruption

Selective extraction of the primary canine (in patients 8-9 years old) with no resorption to align an erupting secondary canine.

Pericoronitis

Mild to moderate inflammatory response surrounding the crown of a partially erupted tooth, commonly seen in impacted mandibular third molars.

Pell & Gregory Classification (Maxillary 3rd Molars)

Classification system based on the relative depth of the impacted third molar within bone relative to the occlusal plane of the second molar (Class A, Class B, Class C).

Pell & Gregory Classification (Mandibular 3rd Molars - Space)

Classification system based on space available between the anterior border of the ramus and the distal surface of the second molar (Class I, Class II, Class III).

Winter's Classification

Classification system that categorizes impacted third molars based on their angulation relative to the long axis of the second molar.

ADA-AAOMS Classification

Classification using dental procedure codes (D7220, D7230, D7240, D7241) to categorize impacted maxillary and mandibular third molars.

Quek et al. Classification

Adaptation of Winter's classification using an orthodontic protractor to measure the angle formed between intersected long axes of second and third molars.

G.R. Ogden Method

Classification method comparing the distance between roots of second and third molars ($A$) to the distance between roots of first and second molars ($B$).

Troughing

Surgical removal of bone around a crown to expose it and create an entry/delivery point for extraction, using the cementoenamel junction as a guide.

Lateral Trephination Technique

Also known as germectomy; prophylactic procedure for 10-16 year olds involving trephination of the buccal cortical plate to remove developing third molars.

Buccal Bone Guttering

Also known as Moore & Gillbe's collar technique or ditching; removal of buccal cortical bone up to the cervical line using a bur to create an elevation point with reduced bone loss.

Postage Stamp Technique

Also called necklace technique; creation of equally spaced bur holes connected to remove a block of bone and form a window exposing up to \frac{1}{3} of root height.

Lingual Split Bone Technique

Technique involving splitting the lingual cortex and elevating the tooth distolingually, recommended for elastic bone in young patients.

Buccal Corticotomy

Alternative surgical approach for deeply seated impacted third molars utilizing a trapezoidal mucoperiosteal flap and rectangular bony window.

Operculectomy

Minor surgical procedure involving the removal of the operculum (pericoronal soft tissue flap) covering a partially erupted tooth.

Coronectomy

Also known as intentional partial odontectomy; surgical removal of the tooth crown while leaving the roots undisturbed in situ.

Pericoronal Ostectomy

Removal of overlying bone to allow an impacted third molar with incomplete root formation ($14 - 18\,years\,old$) to erupt away from the inferior alveolar nerve.

Ecchymosis

Bluish-purple discolorations in the oral cavity or face indicating blood in submucosal or subcutaneous tissue, commonly seen 2-4 days post-surgery in older patients.

Gustatory Agnosia

Loss of the ability to classify, contrast, or identify a given taste stimulus verbally.

Anesthesia

Complete loss of sensation in a nerve distribution.

Hyperesthesia

Excessive sensitivity of a nerve to stimulation.

Paresthesia

Spontaneous, non-painful subjective abnormal sensation such as burning, tingling (pins and needles), or numbness.

Dysesthesia

Spontaneous and abnormal unpleasant sensation triggered by normal stimuli (e.g., severe burning from a light touch).

Neurapraxia

Seddon's Class I nerve injury featuring temporary conduction block with intact axons and endoneurium, resulting in complete recovery within days or weeks.

Axonotmesis

Seddon's Class II nerve injury marked by loss of axonal continuity while preserving the endoneurium, resulting in slower recovery ($2 - 6\,months$).

Neurotmesis

Seddon's Class III (gravest) nerve injury involving complete severance or severe scarring leading to loss of both axonal and endoneurial continuity.

Segmental Degeneration

Dissolution of myelin sheath in isolated segments (partial demyelination), slowing nerve conduction velocity while leaving axons intact.

Wallerian Degeneration

Process following axonal transection or crushing where the entire axon and myelin sheath distal to the injury site disintegrate.

Tinel's Sign

Clinical sign of nerve regeneration elicited by lightly percussing over an injured nerve to trigger a tingling sensation along its distribution.

Pederson Scale

Radiographic difficulty index ($1 - 10$) evaluating depth, ramus space, and angulation to classify impactions as easy ($3 - 4$), moderate ($5 - 6$), or very difficult ($7 - 10$).