SPACE MAINTAINERS

WATCH VIDEO ON SPACE MAINTAINER >> CLICK HERE

SPACE MAINTENANCE IN THE PRIMARY DENTITION

Space maintenance can be defined as the provision of an appliance (active or passive) which is concerned only with the control of space loss without taking into consideration measures to supervise the development of dentition.

Space maintainers are appliances used to maintain space or regain minor amounts of space lost, so as to guide the unerupted tooth into a proper position in the arch.

IDEAL REQUIREMENTS

• It should maintain the entire mesio-distal space created by a lost tooth.
• It must restore the function as far as possible & prevent over-eruption of opposing teeth.
• It should be simple in construction.
• It should be strong enough to withstand the functional forces.
• It should not exert excessive stress on adjoining teeth.
• It must permit maintenance of oral hygiene.
• It must not restrict normal growth & development and natural adjustments which take place during the transition from deciduous to permanent dentition.
• It should not come in the way of other functions.
• 
  

If you are really benefited , Please share it with your friends on Facebook by clicking Fshare button. Follow us on facebook : http://www.facebook.com/rxdentistry

BONES OF SKULL / OSTEOLOGY OF FACE

Human skull

The skull  is divided into the cranium (all the skull bones except the mandible) and the mandible (or jawbone). One feature that distinguishes mammals and non-mammals is that there are also three ear bones (called ossicles):

• —       malleus (hammer)
• —       incus (anvil)
•                             stapes (stirrup)

Maxilla

  à  is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible, which is also a fusion of two halves at the mental symphysis.

Function

—The alveolar process of the maxilla holds the upper teeth, and is referred to as the maxillary arch. The maxilla attaches laterally to the zygomatic bones (cheek bones).

—The maxilla assists in forming the boundaries of three cavities:

—   the roof of the mouth

—   the floor and lateral wall of the nasal antrum

—   the floor of the orbit

The maxilla also enters into the formation of two fossae: the infratemporal and pterygopalatine, and two fissures, the inferior orbital and pterygomaxillary

Mandible

A.)  Body 

  a.)  Symphysis menti

  b.)  Mental protuberance

  c.)  Mental foramen

  d.)  Mylohyoid line

B.)  Ramus

  a.)  Mandibular foramen

  b.)  Mylohyoid groove

  c.)  Mandibular canal

  d.)  Angle

  e.)  Coronoid process

  f.)  Condyloid process

  g.)  Mandibular notch

If you are really benefited , Please share it with your friends on Facebook by clicking Fshare button. Follow us on facebook : http://www.facebook.com/rxdentistry

Anterior cross bite

Anterior cross bite

Possible causes

Class III skeletal pattern

Crowding

Retained primary teeth and roots

Presence of supernumerary teeth

Trauma

Clinical features

• Instanding maxillary incisor occluding behind the corresponding lower incisors.
• Over bite which can vary from nothing to excessive depth.
• Gingival recession of the lower incisor involved.
• Forward displacement of the  mandible-  instanding tooth comes into premature contact along the normal path of closure.
•      mobility of the lower incisor involved in the cross bite.

Methods available for correction

Spoon handle biting.

Removable appliance with either cantilever spring or screw.

Lower inclined bite plane.

     

Spoon handle biting

Instruct the child to bite on a spoon handle to guide the incisor which is erupting into cross bite.

 Do not attempt this on an erupted incisor which has a positive over bite.

Once cross bite established,

Identify predisposing factors and remove them to prevent development of the cross bite

Once the cross bite is established, identify and remove aetiological factors responsible and select appropriate method for correction.

Removable appliance

Selection of appliance and the spring design depend on,

      Axial inclination of the tooth

Depth of the over bite.

Amount of forward movement required

Number of teeth involved in the cross bite

Appliance design

Select the best active component which should be used depending on the above factors discussed.

Adequate number of clasps

Add adequate number of clasps to the appliance to resist the reaction of the vertical component of the active force.

Appliance design

Add posterior bite plane to disocclude teeth

Instruction to the technician

Adams clasps on 6/6 d /d

Double cantilever spring(Z spring) on /1

Posterior bite plane (half molar capping)

Management of patient

Fit the appliance and give adequate instructions to the patient to wear it regularly including meal time.

Activate the spring by the correct amount.

Adjust clasps and check the thickness of the molar capping.

Give adequate instruction to the parents as well.

Monitor progress of treatment

If cross bite is corrected and depth of the over bite adequate to ensure the stability of the occlusion discontinue appliance

Monitor the development of the occlusion until the occlusion of the permanent dentition is established.

Incisors cross bite before and after correction

Incisor cross bite not corrected early lead to a severe malocclusion 

If you are really benefited , Please share it with your friends on Facebook by clicking Fshare button. Follow us on facebook :