neutral zone impression technique

Neutral Zone Impression Technique

SHAISTA ZAFAR

NEUTRAL ZONE

Gahan and Walmsley (2005) defined neutral zone as the

area in the mouth where during function, the forces

of the tongue pressing outwards are neutralised

by the forces of the cheeks and lips pressing inwards.

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NEUTRAL ZONE

IMPRESSION TECHNIQUE

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It’s a physiological and functional approach that is widely and concisely described as a treatment modality for unstable lower complete denture cases

COMMON COMPLAINTS OF LOWER COMPLETE

DENTURE

PAIN

LOOSENESS-being the most common complain!

MOST EFFECTIVE FOR

who have had

numerous unstable, unretentive lower complete dentures.

EVEN AFTER

HAVING..

LOWER DENTURE??

Atrophies mandible>maxilla

Mandible has less residual ridge for retention and support

Difficulty for positioning the teeth to produce a stable denture

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RESIDUAL RIDGE RESORPTION

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LABIAL RESORPTION

BUCCAL

RESORPTIO

N

LINGUAL

RESORPTION

LINGUAL

RESORPTION

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FUNCTIONAL FORCES

FORCESINWARD FORCES

OUTWARD FORCES

BuccinatorModiolus

Orbicularis orisTONGUE

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INDICATIONS

CATIONSIONS

25

Severely atrophic mandibular ridge

High mentalis attachment

Neuromuscular disease

Atypical shape of oral structures

Trauma

Systemic disease

Locate optimal position for implants.

Partial glossectomy

Motor nerve damage to the tongue

AIM

Is to improve denture stability by constructing a

denture that is shaped by muscle function

and is in harmony with the surrounding oral structures.

OTHER ADVANTAGE

S

Improved stability and retention

Posterior teeth will be correctly positioned allowing sufficient tongue space

Reduced food trapping adjacent to the molar teeth

Good aesthetics due to facial support.

MATERIAL USED FOR

NEUTRAL ZONE IMPRESSION

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Stock trays

Impression Compound

Zinc Oxide Eugenol

Custom tray

Green stick

Orthodontic Ni/Ti wires

Modeling Wax

Tissue Conditioners

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CASE REPORT

Free template from www.brainybetty.com 33EDENTULOUS MAX ARCH EDENTULOUS MANDIBULAR ARCH

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CLINICAL TECHNIQUE

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:Preliminary impression with impression compoundSTEP 1

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STEP 2 Wash impression with Zinc Oxide Eugenol

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A lower acrylic special tray with metal spurs to aid retention of the

impression material

STEP 3

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JAW RELATIONSTEP 4:

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STEP 5STEP 5: Occlusal pillars built in green stick to establish the occlusal height

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STEP 6

Tissue conditioner being molded with the mouth movements

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STEP 7: The tray now kept on the cast

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STEP 8: Plaster index formed around the neutral zone impression Neutral zone impression removed to make the wax rim

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STEP 9: Wax rim formed

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STEP 10: Teeth set up in neutral zone

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CONCLUSIONS

Special impression techniques are useful for the construction of lower complete dentures on highly atrophic ridges in cases where dental implants are not possible

Neutral zone impression technique is a useful technique aims to construct a denture in muscle balance, it is relatively simple but it is demanding both clinically and technically.

REFERENCES Prosthodontic treatment for edentulous

patients- 13th edition by ZARB,HOBKIRK,ECKERT,JACOB

Clinical dental prosthetics-FENN & GIMSON’S

GAHAN, M. J. & WALMSLEY, A. D. 2005. The neutral zone impression revisited. British dental journal, 198, 269-272

http://www.slideshare.net/eugeneyeoh1/piezograph-2

http://www.jaypeejournals.com/eJournals/ShowText.aspx?ID=3376&Type=FREE&TYP=TOP&IN=_eJournals/images/JPLOGO.gif&IID=261&isPDF=NO

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3081261/

F L O B R U S H I S N T S M I L E E E T H A N K Y O U

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