J Dent Rehabil Appl Sci.  2023 Dec;39(4):214-221. 10.14368/jdras.2023.39.4.214.

Neutral zone and alveolar relation consideration for fabricating complete denture in a patient with severe alveolar bone resorption: a case report

• Kim HJ
• Jang Wh
• Park C
• Yun Kd
• Lim HP
• Park SW

• KMID: 2550430
• DOI: http://doi.org/10.14368/jdras.2023.39.4.214

Abstract

In order to fabricate stable dentures in patients with severe resorption of residual ridges, various factors must be considered. One of them is the neutral zone, which is defined as the potential region in which the pressure of the tongue outward in the oral cavity and the pressure of the cheeks and lips directed inward from the outside of the oral cavity equalize during functioning. In patients with severe ridge resorption, if the teeth are usually arranged above the residual ridge, the teeth are located on the lingual side rather than the original position. Therefore, the functional space of the tongue is invaded, the tongue is positioned backward, and the sealing of the lingual border is broken, which acts as a factor reducing the maintenance of denture. In addition, it is also important for the stability of dentures to assume an interalveolar crest line connecting the maxillary and mandibular ridge crests, and to arrange the maxillary and mandibular artificial teeth to match the masticatory force to the interalveolar crest line. Therefore, good clinical results were obtained by fabricating dentures for the patient with poor alveolar residual ridge using neutral zone impression and ridge relationship analysis.

Keyword

complete denture; neutral zone; residual ridge

Figure

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  Fig. 1 Initial intraoral photographs. (A) Maxillary occlusal view, (B) Frontal view, (C) Mandibular occlusal view, (D) Initial panoramic radiography.

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  Fig. 2 Temporary denture delivery. (A) Right view, (B) Frontal view, (C) Left view.

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  Fig. 3 Final impression of (A) Maxilla, (B) Mandible and definitive casts of (C) Maxilla, (D) Mandible.

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  Fig. 4 (A) Facebow transfer, (B) Jaw relation record, (C) Mounting of master casts on articulator.

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  Fig. 5 Captured images of (A) Master casts & occlusal rim scanning, Cross sectional view on 1st molar & Inter-alveolar crest line analysis (B) Right, (C) Left.

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  Fig. 6 Neutral zone impression Putty index for resin stop of (A) Maxilla, (B) Mandible, Resin stop fabrication with VD maintained of (C) Maxilla, (D) Mandible, (E) Mounting with VD maintained, Neutral zone impression with tissue conditioner of (F) Maxilla, (G) Mandible, Putty index for tooth arrangement of (H) Maxilla, (I) Mandible and Tooth arrangement of (J) Maxilla, (K) Mandible.

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  Fig. 7 External surface impression with wax denture.

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  Fig. 8 Captured image of comparison of final & temporary denture (green line: final denture, red line: temporary denture).

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  Fig. 9 Definitive denture delivery (A) Right view, (B) Frontal view, (C) Left view and Extraoral photograph with denture (D) Frontal view, (E) Lateral view.

Reference

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