surgical procedure: the safe system

This document describes the procedure

to follow when using the SAFE System for

surgery. The SAFE System can be incorporated

in all types of SurgiGuides. The System can be

used pre-operatively and surgically in a

Secure, Accurate, Flexible and Ergonomic way.

Following these guidelines will improve

the surgical results.

Surgical Procedure: The SAFE System®

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Introduction

The SAFE System offers the surgeon a series of tools for Secure, Accurate,Flexible and Ergonomic implant placement. Position, angle and depth of dril-ling as well as implant placement are guided through the use of SAFE in com-bination with SurgiGuides, resulting in an improved implant position.

To have good results in using the SAFE System, several surgical decisions, e.g.planned implant length and depth control, have to be taken care of duringdesign and production of the SurgiGuides. Therefore final decisions are madeearlier in the planning process, and the correct information should be transfer-red to the manufacturer of the SurgiGuide.

For maximum accuracy the surgeon should be in possession of a SAFE SurgicalTray and storage box, containing different types of reusable components, aswell as a starter set of SAFE System pilot/final drills.It is crucial that the surgeon maintains a complete inventory of components,particularly the drills, as the SAFE guides are fabricated on the premise that allrequired components are available during surgery. Only by re-ordering com-ponents and drills when needed, can the correct use of the SAFE System beguaranteed in any situation, maximising the accuracy of the SAFE System.

Planning actions

To achieve full advantage of the SAFE System, the planning phase is the key-stone of the process. The design of implant lengths and other indications mustbe checked earlier, in the planning process, in order to incorporate depth con-trol in the design of the guide.

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1 Planning of implant position

It is very important to carefully plan the position, angulation and depth of eachimplant. The SimPlant Concept can be used to plan your implants in a 3Denvironment based on CT images, taking into account bone quality, quantityand esthetic considerations. It is extremely important that implant position andangulation as well as depth are accurately planned, because SAFE guides willincorporate the depth control for the surgical process.

2 Planning of implant length

In order to incorporate depth control for drilling and implant placement, it isextremely important to plan the implant length before manufacturing of the gui-des takes place. The information that you provide will be used to manufacturethe guides. Based on CT information in SimPlant, the maximal length of eachimplant can be defined depending on the bone quantity. If allowed by the ana-tomy of the patient, it can be helpful to have all implants of the same length.Doing this may result in an eased surgical phase since fewer components willbe needed to drill and place the implants.

Important remark: Providing depth control in the design phase of theSurgiGuide will guarantee to have the complete diameter of the drilled holeover the complete length of the implant to be placed. However, because of thedesign of the drills, the actual drill point (Y-factor) will insert slightly deeper intothe bone than the actual apical point of the planned implant. Therefore it is cri-tical to include a safety region around critical anatomical structures.

3 Planning of implant diameter

The implant diameters should be chosen depending on the anatomy of thepatient, taking into account the bone crest geometry and the bone density. Ifno clinical and/or mechanical contra-indications exist, it might be useful tochoose a smaller implant diameter in areas with very dense bone, eliminatingthe need for implant tapping during the surgical process. Even for largerimplant diameters, the drilling process can be performed taking full advantageof the SAFE System, though technical restrictions might prevent the possibilityfor the actual implant guidance.


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Pre-operative actions

1 Complete Surgical Tray/Drill set

Check carefully if all necessary compo-nents are available. It is up to the surge-on to keep these sets/kits complete and toreplace components when needed. Onlyafter the technician has designed theSurgiGuide, the necessary componentswill be known. If there is any doubt whichcomponents to use for which implant site,please contact the manufacturer of theSurgiGuide to request the necessary information before proceeding.

2 Check drilling tubes

Check carefully if the drilling tubes are easily screwable into the tubes incor-porated in the SurgiGuide. For ease of handling, it may be necessary to use an instrument such as for-ceps, pince, or pliers to transfer the drilling tubes during surgery. It might alsobe useful to secure the drilling tubes using a small thread around the collar ofthe tubes in case they may loosen and fall into the throat of the patient.

3 Check drills

Check if the drills to be used will pass easily through the drilling tubes until thelevel of the physical stop. Also check to see if the depth of the osteotomies tobe created and the measures you have taken for mucosa thickness or otherimportant parameters is realistic compared to your planned implant length. Ifthere is any doubt about the correct transfer of the implant depth, it is recom-mended to use your standard procedure for controlling the depth of the implantsites, and not to rely on the physical stops of the drills.

4 Check implant holders

Check to see if the implant holders pass easily through the guiding tubes incor-porated into the guide until the level of the physical stop. Also check to see ifthe transfer of the implant placement and the measures you have taken aboutmucosa thickness or other important parameters is realistic compared to your

Fig. 1: Surgical tray


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planned implant length. If there is any doubt about the correct transfer of theimplant depth, it is recommended to use your standard procedure for control-ling the depth of the implant sites, and not to rely on the physical stops of theimplant holders.

5 Perform all regular checks for SurgiGuide

Perform all regular checks for the SurgiGuide, that are recommended by themanufacturer of these devices. The use of the SAFE System does not affect orexclude the recommendations provided by your guide manufacturer. If theguide will be fixed to the jaw during surgery using osseosynthesis screws, allnecessary adaptations to aid this fixing should be done before surgery, outsidethe surgery theatre. Also disinfection and sterilisation of these acrylic devicesshould be done according to the manufacturer’s recommendations.

6 Preparation of surgery according to planning

As all components to be used during surgery are known beforehand, becauseall parameters are incorporated in the design of the guide, surgery should beprepared to prevent any mistakes in equipment during surgery. It might be helpful to position the needed components in astructured way onto the dynamic surgical tray.The dynamic surgical tray is designed to repre-sent the sixteen tooth positions of a regularpatient jaw. The different components neededfor each implant site can be positioned easilyat the correct tooth position. It is important toposition the correct drills and implant holdersfor each implant site. If the same componentsare needed for multiple tooth positions, thecomponents can be positioned at any of thesepositions. Also general components, like screwdriver, handpiece connector for theimplant holders and/or trephine can easily bepositioned in this dynamic surgical tray.By transferring the planning completely to thesurgical tray, the actual transfer to the surgeryis much easier. Fig. 2: Surgical tray prepared for

placement of six implants


7 Sterilization of the Surgical Box with components

Close the Surgical Box with all components in it and sterilize the box accordingto the recommendations by the box manufacturer, which can be found in thestandard documentation accompanying the box.

Surgical Procedure

1 Standard precautions for SurgiGuide

Use the standard procedures for these type of devices, which are indicated bythe manufacturer. Position the guide in the patient’s mouth according to therecommendations for the specific guide type. Check their fit and stability. Ifthere is any reason to believe that the SurgiGuide does not transfer accuratelyinto the implant positions or does not fit sufficiently on the supporting surface,the predictability offered by the SAFE System cannot be guaranteed.

2 Final positioning of the SurgiGuide

If the SurgiGuide is approved and will be used for surgery, stabilize the guideon its final position. If no tissue punch is needed, it is recommended to havethe internal drilling tubes already screwed in before the final positioning. Insome situations, the guide might be fixed to the jaw by using small osseosyn-

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thesis screws. If the guide will not be fixed, take all necessary actions to avoidmovement of the device during surgery. As only one guide will be used for thecomplete implant placement process, including drilling and the actual place-ment, the final positioning of the SurgiGuide is extremely important. Any mis-fit of the guide will cause less predictability offered by the SAFE System.

3 Punching/Trephine

If a transmucosal approach is being used for implant placement, decide onpunching the implant sites depending on the amount of keratinized tissue. Ifpossible, the punching should be done without removing the SurgiGuide. Aspecially designed trephine is available for this purpose. In some situations, theuse of the trephine is also recommended for removing any remaining tissuethat may prevent the implant holders from reaching the correct depth. If for anyreason it is necessary to remove the guide, the previous steps of checking thefinal position of the device should be redone.

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Fig. 4: Use of trephine to remove tissue for correct depth control 1

Fig. 3: Fixed SurgiGuide on patient mandible 1


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4 Pilot drilling to physical stop

According to your planning, use the correct pilot drill for the correct osteotomyand perform the drilling until the physical stop touches the tube. Take thenecessary precautions to cool the drill during drilling. As soon as the physicalstop touches the drilling tube, the correct drill depth has been obtained. It isstrongly recommended not to use excessive forces to push the platform ontothe drilling cylinders. This action can cause extreme heating of the tube anddrill because of excessive friction, and may cause difficulties in removing thedrilling cylinder afterwards. Repeat the pilot drilling process for all the osteoto-mies to be created.

5 Final drilling to physical stop

Within the same internal tubes, use the correct final drill for the correct osteo-tomy according to your planning, and perform the drilling until the physicalstop touches the tube. Take the necessary precautions to cool the drill duringdrilling. As soon as the physi-cal stop touches the drillingtube, the correct drill depthhas been obtained. It is stron-gly recommended not to useexcessive forces to push the

Fig. 5:Pilot drilling to physical stop 1

Fig. 6:Final drilling through same internal tube 1


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platform onto the drilling cylinder. This action can cause extreme heating of thetube and drill because of excessive friction, and may cause difficulties in remo-ving the drilling cylinder afterwards. Repeat the final drilling process to finalizeall osteotomies for all planned implants.

6 Remove drilling tubes

When removing the drilling tubes use forceps, pince or pliers. Take care not toloose any drilling tubes into the patient’s throat. Using a thread around theinternal tubes to secure them externally can aid in the removal process. Takeextreme care not to adjust the positioning of your guide during removal of thetubes.

7 Additional implant site preparation

If needed, perform any additional implant site preparation according to theimplant manufacturer, without removing the guide. Tapping can be donethrough the guiding tubes. As the tapping process is most important at theentry point of the implant to overcome the cortical bone surface, it is not neces-sary to tap the complete length. It might be useful to use the trephine to flat-ten the surgical site surface by removing remaining tissue or bone particleswhich may prevent the implant holder from reaching the correct depth.

Fig. 7:Tapping performed through the SurgiGuide 1


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8 Implant placement

Screw the correct implant holders on the corresponding implants, according toyour planning. If the implants used are provided attached to a fixture mount ofthe manufacturer, exchange the implant holders by making use of the titanti-um containers in the SAFE Kit to ease this process.Perform the implant placement through the guiding tubes until the phyisicalstop touches the guiding tube. It is strongly recommended not to use excessi-ve forces to push the platform onto the guiding cylinder. This action can causeextreme heating because of friction, or might cause your implants to loose theirprimary rotating stability. It might be useful to take mechanical considerationsinto account in the choice of which implants to place first. This can provideextra stabilization of the guide and reduce relative errors. It is recommendednot to remove the implant holders until all implants have been positioned.

9 Remove implant holders and guide

Remove the implant holders by loosening the screw connecting the implantwith the implant holder. Use the correct equipment to unscrew, making surethe unscrewing is complete before you remove the implant holder.

10 Finishing of the implant sites

Remove the SurgiGuide and finish the surgery site as recommended by theimplant manufacturer. The SAFE System has transferred the planned implantpositions in a predictable manner to the actual patient’s jaw.

Fig. 8:Implant Placement throughSurgiGuide using SAFE ImplantHolders 1


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Important Remark

In some situations, it might be useful to completely follow the surgical pro-cedures for only one or two implants to improve stabilization of the guideand to reduce relative errors. The surgical procedure then should be repea-ted afterwards for all other implants.

Post-operative actions

After completing the surgery, clean and/or sterilize all used components.Decide whether any components are needed to be reordered at this moment,to be sure your SAFE Surgical Kit is complete and ready to perform your nextsurgery.

Fig. 9:Finishing of the implant site according to the recommendationsof the manufacturer 1

1 Pictures belong to Dr. P. Tardieu, Grenoble, France


Special thanks to: Dr. P. Tardieu, Grenoble, France Dr. L. Vrielinck, Genk, Belgium

[email protected]@materialise.comwww.materialise.com

Tel. Belgium: +32 16 39 66 66Tel. USA: +1 443 557 0121


surgical procedure: the safe system

Documents

safe guides

introductionthe safe

use of safe

safe surgicaltray

safe system pilotfinal

depth control

planning of implant

planned implant length