Impacted Wisdom Tooth: How to Prevent Complications (1/5)
Don’t let tooth impaction affect your quality of life. understand the causes, symptoms, and treatment options for impacted teeth.
Table of Contents
Theories of Impaction
1. Orthodontic theory
- The jaws develop in a downward and forward direction.
- The growth of the jaws and movement occur in a downward and forward direction, so anything that interferes with such movement will cause impaction.
- Shorter jaws mean a decreased amount of space, which leads to impaction.
- A dense bone decreases the movement of teeth in the forward direction.
- In early mouth breathers, dental arches get constricted and narrowed, which affects the position and alignment of permanent teeth.
- In the case of a well-established deformity, the third molar trying to erupt gets impacted.
2. Endocrinal theory
- Growth hormone is responsible for proper growth of the jaws.
- Lack of the function of the anterior lobe of pituitary gland results in insufficient amount of growth hormone which leads to lack of growth of the jaws.
3. Phylogenic theory
- The phylogenetic theory proposes that the reduction in human jaw size over time is an evolutionary adaptation influenced by changes in diet and masticatory forces.
- This theory suggests that as human jaws have become smaller due to dietary shifts towards softer foods, there may not be enough space in the dental arches for the proper eruption of third molars, leading to impaction.
- More the functional masticatory force, better is the development of the jaws.
- Use of large powerful jaws has been eliminated due to changing nutritional habits. Over the centuries the size of maxilla and mandible has decreased leaving insufficient room for third molars.
- Therefore, the third molar may occupy an abnormal position and may be considered as vestigial organ without any function.
4. Mendelian theory
- According to this theory, heredity is the most common cause and plays a major role in impaction.
- This may be important etiological factor in the occurrence of impaction.
- Genetic factors play a significant role in determining the size and shape of the jaws and teeth, which can impact the alignment and eruption of the third molars.
- In cases where there is a mismatch between the size of the jaw and the size of the teeth, particularly the third molars, impaction may occur due to inadequate space for eruption.
- An individual may genetically receive small jaws from one of the parents and may receive complement of larger teeth from the other parent.
5. Pathological theory
- The pathological theory of tooth impaction involves various factors that can contribute to this condition. One of the primary reasons for tooth impaction is a lack of space in the jaw for the tooth to erupt properly.
- Developmental Factors:
- Genetics: Genetic factors play a significant role in determining the size and shape of the jaw, which can influence tooth eruption patterns.
- Dental Anomalies: Conditions such as supernumerary teeth (extra teeth) or abnormal tooth development can lead to impaction.
- Early Loss of Primary Teeth: Premature loss of primary (baby) teeth can disrupt the natural eruption sequence of permanent teeth, potentially causing impaction.
- Obstruction and Blockage:
- Soft Tissue Obstruction: In some cases, soft tissue such as gums or fibrous bands can obstruct the path of tooth eruption.
- Hard Tissue Obstruction: Impaction can also occur if there are physical barriers like bone or other teeth blocking the tooth’s path.
- Condensation of the osseous tissues caused due to tooth inflammation or infections in an individual may further prevent the growth and development of the jaws.
Etiology of Impaction
Local causes:
- Obstruction for eruption:
- Irregularity in the position of the adjacent teeth.
- Density of the surrounding and overlying bone.
- Lack of space in the dental arch: may be due to
- Crowding of teeth
- Presence of supernumerary teeth
- Crowding of teeth
- Dilacerations of roots: may be due to trauma
- Presence of any soft tissue or bony lesion
- Ankylosis of primary or permanent teeth
- Ectopic position of the tooth bud
- Over retention of deciduous teeth
- Habits involving:
- Thumb sucking
- Finger sucking
- Tongue thrusting
- Pencil sucking, etc.
Systemic causes:
- Prenatal causes:
- Heredity
- Post natal causes:
- Malnutrition
- Anemia
- Rickets
- Congenital syphilis
- Tuberculosis
- Endocrinal disorders of:
- Parathyroid
- Thyroid
- Pituitary gland disorders like: hypothyroidism
- Hereditary linked disorders like:
- Osteoporosis
- Down’s syndrome
- Hurler’s syndrome
- Cleft lip and palate
Indications for Removal of Impacted Teeth
- Prior to orthodontic treatment
- Tooth in line of fracture
- Retained deciduous teeth
- Recurrent pericoronitis
- Deep periodontal pocket
- Prevention of root resorption and caries
- Management of cysts and tumors
- Prophylactic removal
- Anterior crowding
- Facial pain
- Damage to surrounding teeth
- Difficulty eating or speaking
Contraindications
- Compromised medical status
- Extremes of age
- Deeply embedded impacted molar
- Poor prognosis of 2nd molar
- Abutment selection
- Uncontrolled active pericoronal infection
- Socio-economic status
- Excessive damage to adjacent structures
Classification of Impacted Teeth
Winter’s classification
- According to angulation:
Winter’s classification of impacted teeth is based on the inclination of the impacted wisdom tooth (third molar) to the long axis of the second molar. This classification system helps in assessing the position and difficulty of removal of impacted teeth. Winter’s classification includes several categories:
- Vertical Impaction: The impacted tooth is oriented vertically, with its long axis parallel to the long axis of the second molar.
- Horizontal Impaction: The impacted tooth is positioned horizontally, with its long axis perpendicular to the long axis of the second molar.
- Mesio-Angular Impaction: The impacted tooth is angled towards the front (mesial) aspect of the mouth.
- Disto-Angular Impaction: The impacted tooth is angled towards the back (distal) aspect of the mouth.
- Inverted Impaction: The impacted tooth is upside down or inverted in its orientation.
- According to depth:
- Position A: The highest position of the tooth is on a level with or above the occlusal line.
- Position B: The highest position of the tooth is below the occlusal plane, but above the cervical level of the second molar.
- Position C: The highest position of the tooth is below the cervical level of the second molar.
Pell and Gregory’s classification
Pell and Gregory’s classification system for impacted teeth is based on the relationship between the impacted lower wisdom tooth (3rd molar) to the ramus of the mandible (lower jaw) and the 2nd molar, considering the available space distal to the 2nd molar. The classes are defined as follows:
- Class I: A sufficient amount of space is available between the anterior border of the ascending ramus and the distal side of the second molar for the eruption of the third molar.
- Class II: The amount of the space available between the anterior border of the ramus and the distal side of the second molar is less than the mesiodistal width of the crown of the third molar.
- Class III: The third molar is totally embedded in the bone from the ascending ramus because of absolute lack of space available.
- Based on occlusal plane:
- Level A: The occlusal plane of the impacted tooth and the adjacent tooth are at the same level.
- Level B: The occlusal plane of the impacted tooth lies between the occlusal plane and the cervical line of the adjacent tooth.
- Level C: The occlusal plane of the impacted tooth lies apical to the cervical line of the adjacent tooth.
Classification of maxillary canine
Impacted canines are a common issue encountered by oral surgeons, and they can present at various ages with incidental findings.
- Class I: The impacted cuspids/canines are located in the palate. It can be:
- Horizontal
- Vertical
- Semi-vertical
- Class II: The impacted cuspids are located in the buccal or the labial surface of the maxilla. They can be:
- Horizontal
- Vertical
- Semi-vertical
- Class III: The impacted cuspids are located in the maxillary bone. E.g.: the crown of the cuspid is on the palate and the root passes through the root of the adjacent teeth and ends in the buccal surface.
- Class IV: The impacted cuspids are located in the alveolar process. They are usually present vertically between the incisors and the first bicuspids/premolars.
- Class V: The impacted cuspids are located in the edentulous maxilla
Impacted Wisdom Tooth: How to Prevent Complications (3/5)
Understand the steps involved in creating this flap design for improved access and visibility during surgical procedures.
