J Dent Rehabil Appl Sci.  2019 Jun;35(2):64-71. 10.14368/jdras.2019.35.2.64.

Comprehensive understandings in the shape of retromolar pad and its classification based on clinical application

• Park CJ
• Ko KH
• Huh YH
• Cho LR

• KMID: 2451753
• DOI: http://doi.org/10.14368/jdras.2019.35.2.64

Abstract

Retromolar pad is one of anatomical landmarks to use clinically for determining of specific occlusal plane level in edentulous patients and is inherently a soft tissue mass; located at the distal end of mandible and should be covered with denture. The shapes of retromolar pad show variability because it might be inevitable to be resultant forms from healing and remodeling process after the extraction of last molars. Considerations would be focused on those resultant shapes and classification with anatomical relationships and clinical significances.

Keyword

retromolar pad; variability; shape; classification

MeSH Terms

Classification*
Dental Occlusion
Dentures
Humans
Mandible
Molar

Figure

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  Fig. 1 Bony structures of retromolar region. Retromolar triangle is located behind a third molar and retromolar fossa, an ovoid depression, is deeper, more laterally placed and larger than the retromolar triangle. Unlikely the retromolar triangle, it can be palpated. Retromolar fossa is bounded laterally by the external oblique ridge and its continuation in the anterior border of the ascending ramus; medially it is bounded by the temporal crest and at a lower level by the buccal border of the small retromolar triangle.

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  Fig. 2 Relationship between retromolar papilla and retromolar pad when a third molar is present. Directly overlying the base or mesial side of the bony retromolar triangle is the retromolar papilla, a small rolled or crescent-shaped elevation of the mucosa. Retromolar pad is posteriorly continuous with the pterygomandibular raphe. (A) The distal half of a third molar is partially covered with retromolar papilla. (B) Retromolar papilla is clearly located surrounding the distal surface of a third molar.

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  Fig. 3 Relationship between pear shaped pad and retromolar pad when a third molar is not present. After losing last molars, retromolar pad is anteriorly blended with a new elevation, so called, pear shaped pad. Pear shaped pad consists of fibrous tissue of the same kind as that forming the gingival mucosa, it is directly in line with the crest of the edentulous alveolar ridge, and it forms the distal termination of this residual structure. (A) An existed third molar was extracted and consecutively, soft tissue healing and bone remodeling process created the fusion with previously surrounding structures. (B) A third molar is congenitally missing. Relatively, smooth and long soft tissue continuity is shown behind a second molar.

Reference

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