Pontic Design in Prosthodontics

The pontic, \pŏn΄tĭk\, is an artificial tooth on a fixed partial denture that replaces a missing natural tooth, restores its function, and usually restores the space previously occupied by the clinical crown. An ideal correctly designed posterior pontic should have the following features.

  • All surface should have convexity with proper finish.
  • The contact with buccal contiguous slop should be minimal (pinpoint)) and with pressure free (modified ridge lap).
  • Buccal and lingual shunting mechanism should conform with those of the adjacent teeth.
  • Occlusal table should be in functional harmony with the occlusion of all of the teeth.
  • The overall length of the buccal surface should be equal to that of the adjacent abutment teeth or pontic.

The Pontic design can be classified into two types.

A. Pontic having mucosal contact

  1. Sanitary/Hygienic/Fish-belly and
  2. Modified sanitary type

B. Pontic with no mucosal contact     

  1.  Saddle/Ridge lap
  2.  Modified Ridge Lap
  3.  Conical
  4.  Ovate

 

Sanitary or Hygienic Pontic or Fish-Belly 

Sanitary pontic makes no contact with the edentulous ridge. It is made in an all-convex configuration, faciolingually and mesiodistally. The space between the pontic and the mucosa should be 2 or 3 mm[2]. It is most commonly used in mandibular molar replacement. It has the advantage of providing good access for maintaining hygiene with the disadvantage of poor esthetics.

Image of sanitary pontic design
Sanitary pontic design-note the convexity at cervical region

Modified Sanitary

The tissue facing surface of the modified sanitary design pontic has a hyperbolic parabola. The pontic is designed as a concave archway mesiodistally while the under surface is convex faciolingually. It in indicated in molar replacement, provides access to undersurface for good hygiene, alongwith poor esthetics. 

Image of Modified sanitary pontic design
Modified sanitary pontic design-note the concavity at the cervical region.

Saddle/Ridge Lap

It looks like crown of the tooth because it replaces all the contour of the missing tooth. It maintains a large concave contact with the underlying ridge and obliterates facial, lingual and proximal embrasures. Esthetic wise it provide best result but due to impossible access to under surface for cleaning, its use is limited for the replacement of maxillary incisors.

Image of saddle or ridge lap pontic designModified Ridge Lap

Modified ridge lap combines esthetics with easy cleaning, and makes contact with ridge tissues in a shape of ‘ T whose vertical arm ends at the crest of the ridge. This design is most commonly used in the area of the mouth that is visible during function, e. g. anterior teeth, premolars and sometimes maxillary molars. 

Image of modified ridge lap pontic design
Modified ridge lap pontic design: note the half concave underneath surface in contact with mucosa.

Conical

Conical pontic design is mostly limited to the replacement of thin knife edged ridges in the non-display zone of the mouth. It has a convex surface with only touching the centre of the residual alveolar ridge. It helps maintain good hygiene with poor esthetics. Conical design in indicated for the replacement of molars.

Image of conical pontic design
Image of conical pontic design- note the egg shaped design in green circle.

Ovate

Ovate pontic design is the most aesthetically suitable appealing design that looks like emerging from the gingiva. When ridge resorption is corrected by ridge augmentation, ovate design appears to be emerging through gingiva just like natural tooth. it is indicated for the replacement of maxillary incisors, canines, and premolars. It has the advantage of best esthetics, negligible amount of food entrapment and easy cleaning. The disadvantage is the requirement of surgical preparation of the receiving site before prosthesis fabrication.

Image of ovate pontic design
Ovate pontic design-note the convex undersurface of pontic embedded in mucosa (green circle).

 

There are MCQs on pontic design in “Free silver Course“, which you may like to attempt.

 

References:

  1. Eur J Dent. 2018 Jul-Sep; 12(3): 375–379. doi: 10.4103/ejd.ejd_232_18
  2. Rosenstiel & Tyllman respectively
  3. Pontics

 

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