An anterior fixed partial denture is contraindicated when:
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a- Abutment teeth are not carious.
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b- An abutment tooth is inclined 15 degrees but otherwise sound.
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c- There is considerable resorption of the residual ridges.***
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d- Crown of the abutment teeth are extremely long owing to gingival recession.
 
anatomo-physiological disorders:
The practitioner frequently receives in consultation edentulous total patients with flat or negative mandibular crests with all the resulting anatomo-physiological disorders. Achieving prosthetic stability is seen as a challenge to overcome.