Lec13

Pedodontic

Lec.13 Dr. Sara Medhat Al-Dabbagh
Fifth stage
Premature loss of second primary molar
Have less effect on the teeth in anterior segment than the loss of a first primary molar.
However, an irregularity may develop in the permanent molar relationship.
Early loss of the second primary molar is invariably followed by mesial drifting of the first permanent molar.
And possible impaction of second premolar
Also a maxillary molar often will rotate mesial in.

The space-maintaining appliances that are generally advocated are

The band and loop with the band placed on the first permanent molar if the first primary molar is the abutment tooth, it may be lost before the time when the space-maintaining appliance can be discarded.
The passive lingual arch : the soldered lingual arch may be the space maintainer of choice after the multiple of primary teeth in the mandibular arch

Also, the upper lingual arch (Nance appliance) arch

Is the appliance of choice when bilateral loss is present or lee way space should be preserved.

Disadvantages:

Does not restore function.
Advantages:
The use of lingual arch essentially eliminates the problem of patient cooperation.
With properly fitted bands and a well-made appliance, there should be no problems with breakage or retention and no concern about whether the child is wearing it.
Transplatal arch
Indicated when one side of the arch is intact and several primary teeth are missing on the other side. In this case, the rigid attachment to the intact side usually provides enough stability for space maintenance. However, when primary molars have been lost bilaterally, both permanent molars may tip mesially with a transplatal arch. A conventional lingual arch or Nance appliance is preferred in this situation.

Loss of the second primary molar before eruption of the first permanent molar

Mesial movement and migration of the first permanent molar often occurs before eruption in instances of premature loss of the second primary molar.
The distal shoe appliance
A crown and band appliance with a distal intragingival extension used to maintain space or, in some instances, to influence the active eruption of the first permanent molar in a distal direction.

Contraindications:

If several teeth are missing, abutments to support a cemented appliance may be absent.
Poor oral hygiene.
Lack of patient and parenteral cooperation
Certain medical conditions, such as blood dyscrasias, immunosuppression, congenital heart disease because it is associated with a chronic inflammatory response.
In case in which use of distal shoe is contraindicated, two possibilities for treatment exist:
Allow the tooth to erupt and regain space later or
Use a removable or fixed appliance that does not penetrate the tissue but places pressure on the ridge mesial to the unerupted permanent molar.


Areas of multiple primary molar loss
Removable acrylic partial dentures
Passive lingual arch (Nance appliance)
Transpalatal arch
It is occationally necessary to recommend extraction of all the primary teeth in a preschool child and wear complete dentures before eruption of permanent teeth.

Loss of permanent molars

The first permanent molar is unquestionably the most important unit of mastication and is essential in the development of a functionally desirable occlusion. A caries lesion may develop rapidly in the first permanent molar and occasionally progress from an incipient lesion to a pulp exposure in a 6 month period. The loss of a first permanent molar in a child can lead to changes in the dental arches that can be traced throughout the child's life. Unless appropriate corrective measures are instituted, these changes include
Diminished local function.
Drifting of teeth
And continued eruption of opposing teeth
The second molars, even if unerupted, start to drift mesially after the loss of first permanent molar.
A greater degree of forward bodily movement will occur with lost of permanent molar in 8 to 12 old children
In older children, if the loss occurs after eruption of second permanent molar, more exaggerated mesial tipping of the second molar can be expected outcome.
Although the premolars undergo the greatest amount of distal drifting all the teeth anterior to the space, including the central and lateral incisors on the side where the loss occurred, may show evidence of movement.
Contacts open and the premolars, in particular, rotate as they fall distally. There is a tendency for the maxillary premolars to move distally in unison, where those in the lower arch may move separately.
When the maxillary first permanent molar loses its opponent, it erupts at a faster rate than the adjacent teeth. The alveolar process is also carried along with the molars and causes problems when prosthetic replacements are needed.

The treatment of patients with the loss of first permanent molars must be approached on an individual basis
If the first permanent molars are removed several years before eruption of the second permanent molars, there is an excellent chance that the second molars will erupt in an acceptable position. However, the axial inclination of the second molars, particularly in the lower arch, may be greater than normal. The decision whether to allow the second molar to drift mesially or to guide it forward in an upright position may be influenced by the presence of a third molar of normal size.
When the first permanent molar is lost after the eruption of the second permanent molar, orthodontic evaluation is indicated, and the following points should be considered: Is the child in need of corrective treatment other than in the first permanent molar area? Should the space be maintained for a replacement prosthesis? Should the second molar be moved forward into the area formerly occupied by the first molar? The latter choice is often the more satisfactory, even though there will be a difference in the number of molars in the opposing arch. A third molar can often be removed to compensate for the difference. Without treatment, the second molar will tip forward within a matter of weeks
Another option to consider is autotransplantation of a third molar into the first molar position