J Dent Rehabil Appl Sci.  2018 Dec;34(4):324-330. 10.14368/jdras.2018.34.4.324.

Neutral zone approach and external impression for rehabilitation of severely atrophic maxillary and mandibular ridges: a case report

• Jo Y
• Ko CW
• Park SW
• Yun KD
• Park C
• Lim HP

• KMID: 2432369
• DOI: http://doi.org/10.14368/jdras.2018.34.4.324

Abstract

In order to produce a stable denture for severe alveolar bone loss area, it is not only important that .0a suitable occlusion is established but also to consider compatibility with the surrounding muscle to form a suitable polished surfaces. Neutral zone is defined as a potential area where the neuromuscular system of the tongue, cheeks and lips is balanced can be determined through the neutral zone impression technique. And if artificial teeth are aligned within the neutral zone and the polished surface follows the anatomical form of the dynamic muscle, higher stability and retention of the denture may be obtained through coordination with the surrounding muscle tissue. This case is being reported since the concept of the neutral zone was applied to a patient with severely atrophic residual alveolar ridge and the result was clinically satisfactory in both function and aesthetics.

Keyword

complete denture; neutral zone; external impression

MeSH Terms

Alveolar Bone Loss
Alveolar Process
Cheek
Denture, Complete
Dentures
Esthetics
Humans
Lip
Rehabilitation*
Tongue
Tooth, Artificial

Figure

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  Fig. 1 Initial panoramic radiograph.

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  Fig. 2 Initial intraoral photographs. (A) Frontal view, (B) Occlusal view of maxilla, (C) Occlusal view of mandible.

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  Fig. 3 Intermaxillary relation record. (A, B) Centric relation record using Gothic arch tracing, (C) Mounting of master casts.

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  Fig. 4 Lower acrylic resin base with compound rim (A, B).

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  Fig. 5 Artificial tooth arrangement according to the silicone putty index.

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  Fig. 6 External impression. (A) Maxillary occlusal view, (B) Mandibular occlusal view, (C) Right lateral view, (D) Left lateral view

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  Fig. 7 Polished surface of new denture. (A) Maxillary occlusal view, (B) Mandibular occlusal view, (C) Lateral view.

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  Fig. 8 Comparison of cross sectional view of new denture (solid line) and pre-existing denture (dotted line) at maxillary 1st molar mesioligual cusp area cross section area by Geomagic® Control X™ (Geomagic® Control X™ version 2017.0.1, Artec3D, Luxembourg).

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  Fig. 9 (A) Pre-existing denture, (B) Definitive denture.

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  Fig. 10 Patient’s profile. (A) Frontal profile of first visit, (B) Frontal profile after definitive denture delivery, (C) Lateral profile of first visit, (D) Lateral profile after definitive denture delivery.

Reference

References

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