Tooth ImpactionHiba Hamid

DEFINITION

IMPACTION:

It is the tooth that has failed to erupt completely or partially to its correct position in the dental arch well beyond its eruption date and its eruption potential is lost.

COMMONLY IMPACTED TEETH

• Mandibular third molar• Maxillary third molar• Maxillary canine• Mandibular premolars• Maxillary premolars• Mandibular canine• Maxillary central incisor• Maxillary lateral incisor

CAUSES OF IMPACTION

LOCAL CAUSES:

• Obstruction for eruption• Lack of space• Ankylosis of primary or

permanent tooth• Ectopic position of tooth bud• Dilaceration of roots• Soft tissue or bony lesions

CAUSES OF IMPACTION CONT’D

SYSTEMIC CAUSES:

• Pre-natal causes: hereditary• Post-natal causes: tuberculosis,

rickets, malnutrition• Endocrinal disorders of thyroid,

parathyroid, or pituitary gland• Hereditary disorders: osteoporosis,

cleft palate

CLASSIFICATION OF IMPACTED TEETH

WINTER’S CLASSIFICATION

According to angulation:oMesioangularoHorizontal / transverse /

invertedoVerticaloDistoangularoBuccoangularoLinguoangular

CLASSIFICATION OF IMPACTED TEETH CONT’D

WINTER’S CLASSIFICATION

According to deptho Position A: highest position of the tooth

is on a level with or above the occlusal line

o Position B: highest position is below the occlusal plane, but above the cervical level of the second molar

o Position C: highest position is below the cervical level of the second molar

CLASSIFICATION OF IMPACTED TEETH CONT’D

PELL AND GREGORY’S CLASSIFICATION

Relation of impacted mandibular third molar to ramus of mandible and the second molar

• Class I: sufficient space available between the anterior border of ascending ramus and distal side of the second molar for the eruption of the third molar

• Class II: space available between anterior border of ascending ramus and distal side of second molar is less than the mesiodistal width of the crown of the third molar

• Class III: third molar is totally embedded in the bone from the ascending ramus because of absolute lack of space

Incidence of impacted mandibular third

molars in population of Bosnia and

Herzegovina: a retrospective

radiographic study

Article Details

Published in Journal of Health Sciences

Corresponding Authors: Sadeta Šeèiæ, Samir Prohiæ, Sanja Komšiæ, Amra Vukoviæ

Department of Oral Surgery, Faculty of DentistryUniversity of SarajevoBosnia and Herzegovina

Submitted on 14th March, 2013Accepted on 3rd June, 2013

AIM OF THE STUDY

Evaluate the incidence and the pattern of impaction of mandibular third molars in population of Bosnia and Herzegovina using panoramic radiographs of patients referred to Department of Oral Surgery, Faculty of Dentistry, University of Sarajevo.

STUDY SAMPLE

• Retrospective analysis of OPG radiographs of pts. referred to Oral Surgery Department, Uni. of Sarajevo, from January 2010 to February 2013.

• Pts. referred with indication of removal of impacted third molars.

• Signed consent was obtained from patients for the study.

• 2000 radiographs were viewed and related data selected from their dental records.

INCLUSION / EXCLUSION CRITERIA

INCLUSION CRITERIA:

• Complete root formation of mandibular third molar

EXCLUSION CRITERIA:

• Pts. younger than 19 years• Poor quality of OPG• Incomplete medical and dental records• Presence of dentoalveolar trauma or other pathological dentoalveolar

condition• Presence of any systemic or craniofacial anomaly or syndrome (e.g. Down

syndrome, Cleidocranial dysostosis)• Absence of mandibular second molar

STATISTICAL ANALYSIS

Data recorded into specially designed forms containing following information: • age, • gender, • place of residence, • region, • impacted tooth, • angulation of impaction (acc. to Winter’s classification), • level of impaction (acc. to Pell and Gregory’s classification), • pathology and complications associated with impacted and semi-

impacted third molars

RESULTS

• 2000 radiographs analyzed. 761 presented with at least 1 impacted third molar.

• 1034 impacted mandibular molars were present: 508 mand. left third molar, 526 mand. right third molar

• 761 patients analyzed in study: 270 males, 491 females. Male to female ratio= 1:1.8

• Age range: 19 – 85 years with mean ± standard deviation: 27 ± 9

• Significant difference in incidence of impaction found between females and males (p<0.05)

• Vertical angulation most common pattern of impaction (65%), followed by mesioangular (20%), horizontal (9%), distoangular (5%), and buccolingual (1%).

CONCLUSION• 38% of pts. presented with at least one

impacted third molar

• Common age group: third decade

• Significant difference in incidence of impaction found between males and females

• Vertical angulation most common pattern of impaction

• Majority of pts. presented with class I of level of impaction