Prosthetic screw fractures in a case with zygoma implants

Recurrent fractures of prosthetic

screws with zygoma implants

Prosthetic screw No screw broken screw

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Situation

• Patient desires: – improved retention of prosthesis in the upper jaw

• Diagnosis:– Ill fitting prosthesis in upper jaw

– Severe atrophy in UJ (Div D, Misch)

• Treatment plan:– Quad zygoma, delayed loading, overdenture

Chronology

• 30/06/2009: Implant placement quad zygoma

• 04/01/2010: second stage

• Prosthetic treatment not in our department

• 09/09/2010: final control

• 05/05/2011: emergency consultation ¾

prosthetic screws were broken

Intake

31/03/2009

31/03/2009: Intake

31/03/2009: Intake

31/03/2009: Intake

31/03/2009: Intake

31/03/2009: Intake

Implantplanning

Analytical Bone Table

26/04/2009: Implant planning

Implant planning according

to the Stella Technique

Treatment

30/06/2009: Postoperative

30/06/2009: Postoperative

04/01/2010: second stage

04/01/2010: second stage

04/01/2010: second stage

Endresult

09/09/2010

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

09/09/2010: end result

Follow-up > 1 j

05/05/2011

Emergency consultation

• 06/06/2011

– Problem:

• Bar loosens frequently and repetitive fractures of

the prothetic screws

05/05/2011: Quad zygoma and repetitive fractures of the prosthetic screws

Prosthetic screw No screw broken screw

05/05/2011: Quad zygoma and repetitive fractures of the prosthetic screws

What are the causes?

What would you do ?