IMPACTED TOOTH It is the tooth that hasfailed to eruptcompletely orpartially to its correctposition in the dentalarch and its eruptionpotential has beenlost.
UNERUPTED TOOTH It is a tooth that is inthe process oferuption and is likelyto erupt based onclinical andradiographic findings.
MALPOSED TEETH A tooth unerupted orerupted which is inan abnormal positionin the maxilla or inthe mandible.
COMMONLY IMPACTED TEETH1. Mandibular third molar2. Maxillary third molar3. Maxillary canine4. Mandibular premolar5. Maxillary premolar6. Mandibular canine7. Maxillary central incisor8. Maxillary lateral incisor.
THEORIES OF IMPACTION1. Phylogenic theory2. Mendelian theory3. Orthodontic theory.
CAUSES OF IMPACTION LOCAL CAUSE Obstruction for eruption Lack of space Ankylosis of primary or permanent tooth Nonabsorbing, over retained tooth Nonabsorbing alveolar bone Ectopic position of tooth bud Dilaceration of roots Soft tissue or bony lesions- fibrosis Habits.
INDICATIONfor removal of impacted teeth Tooth in line offracture. Tooth in line offire.
Recurrentpericoronitis- is theinflammation of thegingivasurrounding acrown of a partiallyerupted tooth.
Deep periodontalpocket- associated withpartially eruptedtooth. Prior toorthodontictreatment- to control the toothcrowding in themandible.
Prevention of rootresorption andcaries Prevention ofpathologicalfractures.
Management ofcysts and tumors.Abscess ofodontogenicorigin Management ofpreprostheticconcerns Prophylacticremoval
CONTRAINDICATION Extremes of age Compromised medical status Excessive risk of damage to adjacent structure When there is question about the future status of thesecond molar Uncontrolled active pericoronal infection Socioeconomic status Fracture of atrophic mandible may occur Abutment selection
SIGN AND SYMPTOMS Pain Difficulty in mastication Paraesthesia of lip Swelling of retro-molar tissue Soreness Erythemia of overlaying soft tissue or operculum Trismus Facial swelling of the affected side Raised temperature Regional lymphodenopathy.
RISK OF NONINTERVENTION Crowding of dentition Resorption of adjacent tooth andperiodontal status Development of pathological conditionssuch as infection, cysts, tumors.
RISK OF INTERVENTION Minor transient- sensory nerve alteration,alveolitis, trismus and infection. Haemorrhage,dentoalveolar fracture and displacement oftooth. Minor permanent- periodontal injury, adjacenttooth injury, temporomandibular joint injury. Major – altered sensation, vital organ infection,fracture of mandible, maxillary tuberosity.
CLASSIFICATION OF IMPACTEDTOOTH1. WINTER’S CLASSIFICTION Acc to angulation1. mesioangular2. horizontal/ transverse/ inverted3. vertical4. distoangular5. buccoangular6. linguoangular
Acc to depth1. Position A : highest position of the toothis on a level with or above the occlusal line.2. Position B : highest position is below theocclusal plane, but above the cervical level ofthe second molar.3. Position C : highest position is below thecervical level of the second molar.
Pell and Gregory’s classificationrelationship of the impacted lower third molar to ramusof the mandible and the second molar.1. Class I : sufficient space available between the anteriorborder of the ascending ramus and the distal side ofthe second molar for the eruption of the third molar.2. Class II : the space available between the anteriorborder of the ramus and the distal side of the secondmolar is less than the mesiodistal width of the crown ofthe third molar.3. Class III : the third molar is totally embedded in thebone from the ascending ramus because of absolutelack of space.
Pell and Gregory’s classificationClass IClass IIClass III
Maxillary third molar classificationacc to relation to the floor of maxillary sinus.1. Sinus approximation (SA)- no bone or thinbony partition present between impactedmaxillary third molar and the floor of themaxillary sinus.2. No sinus approximation (NSA)- 2mm or morebone is present between the sinus floor and theimpacted maxillary third molar.
Classification of impacted maxillarycanines1. class I : palatally placed maxillary caninea. Horizontalb. Verticalc. semivertical2. class II : labially or buccally placed maxillarycaninea. Horizontalb. Verticalc. semivertical
3. class III : involving both buccal and palatalbone4. class IV : impacted in the alveolar processbetween the incisors and first premolar.5. class V : impacted in edentulous maxilla.
Radiological assessment aids indetermining Classification of impacted tooth Orientation of impacted tooth Depth of the tooth Root shape Relation to inferior alveolar canal Localization of impacted tooth
1. Darkening of root2. Deflection of root3. Narrowing of root4. Dark and bifidapex1234
5. Interruption ofwhite line of thecanal6. Diversion of canal7. Narrowing of canal567
Winter’s lines White line – corresponds to occlusal plane.- indicates the difference in occlusal level of second and third molar. Amber line – represents the bone level.- denotes the alveolar bone covering the impacted tooth and theportion of tooth not covered by the bone. Red line – represents depth of the tooth in bone and the difficultyencountered in removing the tooth.- indicates the amount of bone that has to be remover beforeelevation.- if the length of red line is more than 5 mm then extraction isdifficult.- every additional mm renders the removal of the impacted tooththree times more difficult.
Assessment of third molar Case history Intraoral and Extraoral examination Examination of site of impacted tooth Analysis- IOPA and OPG Structure-inferior alveolar nerve-Lingual nerve-Pterygomandibular space-Facial artery-External oblique ridge-Retromolar pad-Retromolar triangle
SURGICAL REMOVAL OF IMPACTEDTEETH1. Asepsis and isolation2. Local anaesthesia/ sedation+ LA/ general anaesthesia.3. Incision – flap design.4. Reflection of mucoperiosteal flap.5. Bone removal.6. Sectioning (division) of tooth.7. Elevation.8. Extraction.9. Debridement and smoothening of bone.10. Control of bleeding.11. Closure – suturing.12. Medication – antibiotics, analgesics, etc.13. Follow-up.
Instruments Mouth mirror Probe No 15 blade on a Bard Parker handle. Mosquito artery forceps Retractors Chisel Bur: rose head, straight fissure Elevators forceps Bone file Needle holder Tissue forceps Scissors Drape Syringe
Asepsis and Isolation Scrubbing + painting of skin and oral mucosa- Cetrimide + absolute alcohol or cetrimide + povidine+ iodine- Cetrimide + absolute alcohol + chlorhexidine. Cleaning solution- used on skin to remove residual soap solution.- Normal saline-Alcohol – spirit Painting solution – act topically to inhibit further growth of microbes- Povidine – iodine 5% for skin, 1% for oral mucosa- Chlorhexidine gluconate - 7.5% for skin, 0.2% for rinsing oralcavity. Drape the patient
Local anaesthesia For mandibular molar and canines – pterygomandibularnerve block. For maxillary molars – posterior superior alveolar nerveblock and palatine nerve block or infiltration. For maxillary canines – infraorbital nerve block + palatalinfiltration of incisive canal and bilateral palatine nerveblocks.
Bone removal Aim1. To expose the crown by removing the bone overlyingit.2. To remove the bone obstructing the pathway forremoval of a tooth. Two ways of bone removal1. High speed, high torque handpiece and technique2. Chisel and mallet technique. Adequate amount of bone should beremoved to enable for elevation
Bur technique No. 7/8 round bur or a straight no. 703 fissure bur isused. Sealed bearing handpieces or surgical handpieces withextra ball bearing must be used. Medium speed drills(12000- 20000r.p.m) are preferredfor dento -alveolar surgery. The bur is used in sweeping motion around the occlusal ,buccal and distal aspect of the crown to exposed it. Once the crown has been located, the buccal surface ofthe tooth is exposed with the bur to the cervical level ofthe crown and a buccal trough or gutter is created. Continuous irrigation with 1% povidine -iodine or withnormal saline to reduce the thermal necrosis of bone.
Lingual split bone technique It is described by Sir William Kelsey Fry. Later popularized by T. Ward. Quick and clean technique. Creates saucerization of the socket, therebyreduces the size of residual blood clot. Used for mandibular third molar especially thoseare placed lingually.
Steps1. 3mm wide or 5mm wide chisel is used2. Vertical stop cut is made by placing the chisel with thebevel facing posteriorly, distal to second molar.3. With the chisel bevel downward, a horizontal cut ismade backward from the lower end of vertical limitingstop cut.4. The buccal bone plate is removed above the horizontalcut.5. The distolingual bone is then fractured inward byplacing the cutting edge of the chisel. Bevel side ofchisel facing upward and cutting edge is parallel to theexternal oblique ridge.6. Finally small wedge of bone , which then remainingdistal to the tooth and between the buccal and lingualcut, is excised and removed.
6. A sharp straight elevator is then applied and minimumforce is used to elevate the tooth, as the tooth movesupward and backward, the lingual plate gets fracturedand facilitates the delivery of the tooth.7. After the tooth is removed , the lingual plate is graspedwith the hemostat and freed from the soft tissue andremoved8. Smoothening of the edges is done with bone file.9. Wound irrigated and sutured
Tooth sectioning, elevation andextraction Reduces amount of bone removal required prior toelevation of the tooth. Reduces the risk of damage to the neighboring teeth. The direction in which impacted tooth should besectioned is dependent on the angulation of theimpacted tooth, based on line of draw of the segments. Can be performed either with bur or chisel. The bur is used in controlled fashion to avoid damage tothe vital structures and surrounding teeth and soft issue. The tooth is sectioned one-half to three-fourths with burand then it is completely sectioned with the elevator.
Tooth sectioning, elevation andextractionSectioning of the1. Horizontally placedlower third molar2. Mesiobuccally placedmolar3. Vertically placed molar4. Distobuccally placedmolar
Elevation1. Coupland elevator- placed at the base ofthe crown.2. Winter cryer’s – may be used in wedgingaction/ buccal elevation. Wedging action is useful, when molar crown issplit vertically down to bifurcation of roots
Debridement and smoothening ofbone margins Irrigation of the socket. Curetting to remove any remaining dental follicle andepithelium. Look for piece of coronal portion, check for remnants ofbone /granulation tissue, bleeding points. Check for caries/ erosion/damage to the adjacent teeth. Round off the margins of the socket with large vulcaniteround bur or bone file. Irrigate the socket again. Control bleeding before suturing.
closure 3-0 black silk and 21or 22mm half circle or 1 25 mm, 5/8circle cutting needle is commonly used. Interrupted sutures given and maintained for 7 days. In case of molars, suture distal to second molar shouldbe placed first and should water tight to prevent pocketformation. In case of palatally placed canines, incisive papillashould be sutured carefully to reduce postoperativebleeding.
Principle of suturing Use few suture as possible Should not be excessively tight. Suture should penetrate the lingual flapclose to and behind the third molar andthe buccal flap further distally
Post Operative instruction Pressure pack for 1hr. Ice application Soft diet for 1sttwo days 1stdose of analgesic should be taken before theanesthetic effect of LA wears off Avoid gargling / spitting / smoking / drinking with straw warm water saline gargling after 24 hrs + mouth washregularly thereafter Suture removal after 7 days.
COMPLICATION Intraoperative complicationsDuring Incision- for molars- facial vessel or buccal vessel may be cut.- for lower canines- mental vessel may e damaged.- for upper canines- incisive canal or greater palatinevessel may be damaged.During Bone Removal- damage to the second molar, damage to the roots ofoverlying teeth, slipping of the bur into soft tissues,fracture of the mandible when using chisel and mallet
During Elevation- Luxation o neighboring/ overlying tooth- Fracture of the adjoining bone- Fracture of the tuberosity- Slipping of the tooth into pterygomandibular/ temporalspaces, sublingual pouch and/ maxillary sinus- Damage to nasal wall/ overlying teeth/ lingual, inferioralveolar or mental nerve.During Debridement- damage to inferior alveolar nerve /lingual nerve- damage to maxillary sinus.
Postoperative Complications- pain- swelling- trismus- sensitivity- loss of vitality of neighboring teeth- pocket formation- sinus tract formation- oroantral fistula- oronasal fistula