J Korean Acad Prosthodont.  2016 Oct;54(4):407-412. 10.4047/jkap.2016.54.4.407.

Neutral zone approach for rehabilitation of severely atrophic maxillary and mandibular ridges: A case report

• Lee JY
• Choi SY
• Lee JH

• KMID: 2388220
• DOI: http://doi.org/10.4047/jkap.2016.54.4.407

Abstract

The neutral zone technique is an alternative approach for the construction of complete dentures on highly atrophic ridges with history of denture instability. This technique achieves two objectives. First, the teeth will not interfere with the normal muscle function, and second, the force exerted by the musculature against the denture is more favorable for stability and retention. In this case of a 78-years-old female patient with severely atrophic ridges who had been using unstable complete dentures, the neutral zone impression technique was used to increase the stability and the retention of dentures. The neutral zone for both arch was located with modeling compound. After the arrangement of artificial teeth within the neutral zone, the external impression was taken to determine the tissue surface. The final dentures showed enhanced stability and retention and the patient was satisfied with the new dentures with respect to functional and esthetic aspects.

Keyword

Neutral zone; Complete dentures; Atrophic ridges

MeSH Terms

Denture, Complete
Dentures
Female
Humans
Rehabilitation*
Tooth
Tooth, Artificial

Figure

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  Fig. 1. Panoramic view at first visit.

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  Fig. 2. Initial intraoral photographs. Severe alveolar ridge resorption was observed on maxilla and mandible. (A) Frontal view, (B) occlusal view of maxilla, (C) occlusal view of mandible, (D) frontal view of old dentures, (E) occlusal view of upper denture, (F) occlusal view of lower denture.

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  Fig. 3. Final impression (A), (B) and master casts (C), (D).

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  Fig. 4. Upper acrylic resin base with retentive loops (A) and compound rim (B), (C) lower acrylic resin base with retentive loops (D) and compound rim (E), (F).

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  Fig. 5. Occlusal plane evaluation and bite registration (A), mounting on articulator (B).

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  Fig. 6. Artificial tooth arrangement according to the silicone putty index. Palatal view (A) and labial/buccal view (B) of upper denture tooth arrangement. Lingual view (C) and labial/buccal view (D) of lower denture tooth arrangement.

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  Fig. 7. External impression on labial (A), buccal (B), palatal (C) surface of upper wax-denture using Coe-Soft (Coe-Soft, GC America, Chicago, IL, USA), External impression on labial (D), buccal (E), lingual (F) surface of lower wax-denture using Viscogel (Viscogel, Dentsply Ltd., Weybridge, UK).

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  Fig. 8. Polished surface (A) and tissue surface (B) of new dentures.

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  Fig. 9. Extraoral view of placement of new dentures. (A) Before insertion of dentures, (B) insertion of old dentures and (C) insertion of new dentures.

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