Missing tooth is it  needed to be replaced

Missing tooth replacement is a necessity, especially   the anterior, front tooth. But it is equally important in the posterior region also.

It is thought in mind that, Dental arch is statistic entity, but certainly  it is not the situation. The maxillary  and mandibular teeth are in dynamic equilibrium, where they support each other. When tooth is lost, the structural integrity of the arch is lost and the tooth realigns to the new  occclusion. Provided teeth adjacent to it may drift bodily, or even tilt, opposing teeth may erupt  into the extraction space.


Such drifted and supra-erupted  tooth can result in food impaction and eventually proximal caries


And even plaque accumulation and periodontal breakdown and loss of tooth.

Importance of contacts and contours  of crown

Contact and contours are an important part of crowns, these contacts and contours  act as spill way for food and prevent food passage into sublingual area.

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          The contact area proximally on molar tooth is located to the occlusal third, except for the second  molar, which is  located to middle third. The contact area should be than just a point and is normally an area. The area cervical to contact area should be flat or concave and never should be convex, since  that can course gingival inflammation. The proximal  contacts are slightty facial to the contour except for the maxillary  1st and 2nd molar which is pretty centralilised. If the contact area is  to narrow, it can act as a area of food wedging especially for fibrous foods, and if the contact area is too wide facio-lingually, they do not deflect food from gingival tissues.

The height of contour or the facial surfaces of all posterior tooth occurs in the cervical third and similar  in the lingual surfaces of maxillary premolars and maxiillary molars.

On mandibular tooth on the lingual side, this height of contour occur in the middle third.

The amount of lingual curvature  varies from 0.5mm on maxillary molars and mandibular 1st premolars and 0.75mm on mandibular 2nd premolars. It is 1mm on mandibular molars. The contours of tooth play on important role because over contouring of tooth can cause  food accumulation on cervical area and gingival inflammation.

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Thus the importance of proper contours in crown is mandatory for preventing food impaction and food accumulation and thus promoting good gingival health.