Dr. Jerome Lipowicz
• Doctor of Dental Surgery at Université Paris VII
• Post-graduate Legal Medicine, Université Paris V
• Post-graduate Implantology, Université Paris V
• Post-graduate Esthetic Dentistry, Université Strasbourg
• French Guided Surgery Academy, President
• International College of Dentists, Fellow
• Digital Dentistry Society, Board of Directors
• Active member of many international organisations.
• Founder of Eugenol.com and Eugenol.us
Marc Baranes, Francesco Zammillo, Romain Barret
Full rehabilitation introduction
Full rehabilitation introduction
After a series of prosthetic failures, a 70-year-old woman presented to our dental practice for a comprehensive fixed prosthetic rehabilitation solution.
She had numerous residual teeth with an overdentured maxillary mobile prosthesis and a mandibular complete denture with two ball attachments on symphyseal implants (Fig. 1A-C).
After the removal of the maxillary roots containing the infection sites, integration of the cone-beam computed tomography (CBCT) data, intraoral impressions and current dentures respecting the vertical dimension (Fig. 2) allowed us to create an ideal wax-up as a basis for the implant treatment plan (Fig. 3).
Since multi-unit restorations require the use of conical abutments, it was decided to use one-piece implants (Kontact MB, Biotech Dental, France), allowing standardisation with the choice of 4.6 multi-unit design. The surgical guides have a stackable design (Fig. 4) based on both magnets and male and female parts (dental technician: Joffrey Benon, Design4me, France).
They are printed and consist of a base guide supported by pins (Fig. 5A), a positioning guide in contact with the antagonistic prosthetic arch (Fig. 5B), an implant positioning guide with metal sleeves (Fig. 5C), and a guide for controlling prosthetic emergencies, which many practitioners can use as a temporary bridge to be bonded directly in the mouth to abutments (Fig. 5D).
Two old mandibular implants were removed, for which no implant abutments were available, and no existing CADCAM library (Fig. 6). The sufficient amount of keratinised tissue and the absence of any indication for bone remodelling enabled flapless surgery in the maxilla (Fig. 7) and mandible with mini-incisions after observation using guided epithelial-conjunctive shallow punches (Fig. 8). This was performed in two stages for patient comfort (Fig. 9A-B).
The implants were placed manually to control the burial of the multi-unit stage. These monolithic implants were chosen for the All-on-X protocol because of the advantage of not having to screw in an abutment at 35Ncm2 if the torque is slightly lower than when the implants are placed (Fig. 10).
Control stages assess correct implant positioning according to planning (Fig. 11).
The insertion torques were greater than 35Ncm, and the RFA indicated ISQ scores of greater than 70 on each implant, authorising immediate loading (Smartpeg 25 for MUA, Osstell, Sweden; Fig. 12).
“The impressions were supplemented by extra-oral photogrammetric recordings.”
Postoperative impressions were taken using scanbodies (52.007, DESS, Spain) in the presence of the base guide to help the laboratory reposition the impressions in the 3D space used for implant planning and thus preserve the recorded vertical dimension (Fig. 13A-B).
The impressions were supplemented by extra-oral photogrammetric recordings (Icam4D, Imetric, Switzerland) to ensure exact positioning between each implant and subsequent passive insertion of the prosthesis (Fig. 14A-B).
PMMA bridges were machined and prepared without a titanium base (Fig. 15) for 24-hour loading for each arch (Fig. 16), with manual screwing.
After 3 months of osseointegration and healing (Fig. 17A-B), new impressions were taken, taking into account the new soft tissue position and the patient’s aesthetic and functional requirements. The use of intra-oral impressions to record provisional bridges in occlusion, soft tissues, implant emergences, and scanbodies (Fig. 18A-B), followed by photogrammetry (Fig. 19), highlights the value of this double impression because inconstant deviations between the measurements taken were noted (Fig. 20).
“This highlights the value of this double impression because inconstant deviations between the measurements taken were noted.”
The production of models using a 3D printer (Pro55S, Sprintray, USA; Fig. 21A-B) enabled us to check the insertion and seating of the final bridge, as well as the occlusion. It helped us to discover that an error had been made in the impression, resulting in a significant lack of left occlusion (Fig. 22A-B).
“The production of models using a 3D printer enabled us to check the insertion and seating of the final bridge.”
A dynamic recording of mandibular kinematics (Twim, Modjaw, France; Fig. 23) combined with a facial scanner (RAYFace, Ray, South Korea) enabled the defects in the first design to be corrected (Fig. 24), validated by new models (Fig. 25A-B).
final work
final work
The final work was based on a homothetic titanium bar machined with a high-strength composite suprastructure (breCAM.HIPC, Bredent, Germany; Fig. 26A-B; Dental technician: Romain Barret, France).
Retroalveolar radiographic checks showed excellent adaptation of the bar on each of the conical abutments (Fig. 27), and follow-up of the bridges at 1 year already testifies to remarkable comfort for our patient (Fig. 28A-C, Fig. 29A-B, Fig. 30).
“The final work was based on a homothetic titanium bar machined with a high-strength composite suprastructure.”
conclusion
conclusion
Undeniably, digital technology facilitates all the steps involved in these complex restorations. It has enabled us, as practitioners and dental technicians, to reduce treatment times and better analyse, understand and resolve complaints. Using these interoperable tools is also less invasive and more comfortable for our patients.
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