case 9 quad with 2 zygoma and 2 pterygoid implants
DESCRIPTION
A case is presented with 4 long implants, two of the implants showing unwanted deviationsTRANSCRIPT
Quad case with 2 long implants in the zygomatic bone and 2 long implants in
the pterygoid bone
Dr Luc Vrielinck MD DDSOral and Maxillofacial Surgery
Comments at [email protected], Belgium
Starting point
• Patient desires: fixed prosthesis in the upper jaw
• Status: Division D atrophy in upper jaw• Treatment plan:
– Quad long implant placement, delayed loading
– Overdenture on a bar
Chronology• 24/04/2008: Placement QZ• 21/10/2008: Second stage QZ• 19/01/2009: final work• Complication: persistent paresthesia of the left maxillary
nerve (see the matching of preoperative and postoperative images)
• 23/08/2010: 22 months follow-up
13/11/2007: Intake
13/11/2007: Intake
13/11/2007: Intake
16 15 14 13 12 11 21 22 23 24 25 26H - - - 2.9 6.5 3.4 3.9 3.9 4.6 - - -
T - - - 2.0 4.2 3.5 2.5 3.6 3.3 - - -
H= height of the bone, T=thickness
Bone table: analysis of thickness and height (in mm) on following tooth positions
Treatment plan
Based on the data of the bonetable the treatment plan was decided on 2 long implants with zygomatic anchorage and 2 long implants with pterygoid bone
anchorage
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
01/02/2008: Planning of the implants using Procera™ Software
• Problem: the drilling directions of both zygoma implants cross each other
• In the Surgical Template; the extension sleeves collide with each other and by consequence the Surgical Template cannot be fabricated
• Solution: the implant treatment is splitted over two Surgical Templates, using the same position of the anchor pins
01/02/2008: Planning of the implants using Procera™ Software
Drillguide 1: including left zygoma implants and both posterior implants
01/02/2008: Planning of the implants using Procera™ Software
Drillguide 2: including right zygoma implant using same anchor pin anchorage as the first dill guide
Surgical technique used in this case
• The Surgical Template N°1 was fixed using a surgical index (under local anaesthesia, with patient sitting
• Patient was then brought under general anesthesia• The drilling of 3 implants was done using Surgical
Template No 1• Surgical Template n°1 was removed and replaced by
Template N°2 using the same anchor pins• Right zygoma implant was drilled• Surgical Template was removed • Implants were placed freehand
24/04/2008: Postoperative imaging
Here we have an obvious problem !Apparent correct position ofboth implants
24/04/2008: Postoperative imaging
Here we have a problem !
29/10/2008: Pre post matching
Frontal view Occlusal view
Distal displacement of the tip of the rightZygomatic implant
Orange= planned position; Yellow = placed position
Top view Left lateral view
Orange= planned position; Yellow = placed position
Cranial displacement of the tip of the left implant with pterygoid anchorage
Discussion of the Surgical Outcome
• 2 out of 4 implants demonstrate a deviation of the tip of the implant of > 1cm resulting in:– for the right zygoma implant: an emergence
of the implant posterior of the zygomatic bone– For the left pterygoid: cranial tilting of the
implant; the tip of the implant entering the pterygopalatine fossa, causing laesion of maxillary nerve (V2)
21/10/2008: second stage surgery
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
23/08/2010: Follow-up 22 months
Very good occlusal distribution of forces
23/08/2010: Follow-up 22 months
Very good occlusal distribution of forces
23/08/2010: Follow-up 22 months
Very good occlusal distribution of forces