Slide-and-tilt stackable surgical guides

Dr Scott D. Ganz

Tue. 19. May 2026

save

Prosthetically driven implant placement has become a fundamental principle in contemporary implant dentistry, particularly in the treatment of edentulous patients requiring full-arch rehabilitation. Advances in 3D imaging, digital treatment planning and CAD technologies have greatly improved the ability to plan implant placement based on the intended restorative outcome.^{1, 2} These innovations have enabled a transition from free-hand implant placement to highly precise guided surgical approaches that integrate surgical and prosthetic workflows.^{2, 3}

Static surgical guides were first developed to translate restorative planning into the surgical field by directing the angulation and depth of osteotomy preparation. With the integration of CT imaging and computer-assisted planning in the late 1990s and early 2000s, guided implant surgery became increasingly predictable and prosthetically driven.^{1, 2} Later, the widespread adoption of CBCT further improved access to 3D imaging and facilitated more accurate digital workflows.¹ Recently, the concept of stackable surgical guides has emerged as an evolution of static guidance systems, particularly in the context of full-arch implant reconstructions utilising immediate loading all-on-X protocols.^{4, 5}

Stackable guide systems consist of a modular sequence of indexed components that attach to a stable base, allowing clinicians to perform multiple surgical and restorative steps—including bone reduction, osteotomy preparation, implant placement, multi-unit abutment positioning and prosthesis delivery—with a high degree of accuracy and reproducibility.

Prior to digital technologies, implant positioning was commonly performed using free-hand surgical techniques with limited prosthetic guidance based on 2D panoramic radiographs. Early surgical guides fabricated from acrylic resin or vacuum-formed materials were used primarily to indicate the approximate location of proposed implant sites based on diagnostic wax-ups to help place implants within the envelope of the proposed restoration. While these guides improved prosthetic orientation, they lacked control over drill angulation, depth and 3D positioning.

The introduction of CT-based implant planning represented a major technological advancement. 3D imaging enabled clinicians to visualise anatomical structures—including the maxillary sinus, inferior alveolar nerve and cortical bone contours—to inform planning of implant placement within the context of the proposed restoration.^{1, 2} Computer-assisted planning software allowed virtual implant positioning based on CT datasets, followed by the fabrication of stereolithographic surgical guides that translated the digital plan to the clinical environment.²

Early stereolithographic guides incorporated metal sleeves within a photopolymer resin body to direct the trajectory of the drilling sequence. These guides enabled more precise control of osteotomy angulation and depth compared with earlier analogue guides.^{2, 3, 6} As digital technologies evolved, CBCT imaging replaced conventional CT in most dental applications owing to lower radiation dose, reduced cost and improved access in dental offices.¹

The integration of CBCT imaging with CAD/CAM technologies further improved implant planning relative to both bone anatomy and prosthetic design while avoiding adjacent vital anatomical structures.^{1, 2} This prosthetically driven approach significantly improved the predictability of implant placement and restorative outcomes. However, static guides produced through these technologies were typically limited to directing the drilling process alone and did not address the multiple restorative steps involved in full-arch reconstruction.³

Fig. 1b: Retracted intra-oral oblique frontal view of the malocclusion, missing and fractured teeth, and uneven occlusal plane.

Fig. 2: Pre-op CBCT-generated panoramic radiograph showing missing teeth, pre-existing implants and crowns, fractured teeth and previous root canal treatment.

Evolution and components of stackable surgical guides

The increasing demand for immediate full-arch rehabilitation created a need for more sophisticated guided surgical systems capable of facilitating both surgical placement and predictable prosthesis delivery during the same procedure.^{7, 8} Stackable surgical guides were developed to address these clinical requirements.⁵

A stackable guide system typically begins with a base frame that establishes the reference framework for the procedure using the existing teeth, a well-fitting denture on the mucosa, or the bone for support, depending on the clinical presentation. Once properly seated, the base guide is secured to the maxillary or mandibular bone with anchor pins. These anchor pins remain in place throughout the procedure and the base frame serves as the indexing foundation for sequential guide components.

The subsequent guide system components are designed to attach to the base frame through a series of indexing features or receptors such as mechanical slots, keyed interfaces, magnets, fixation sleeves or pin-retained connectors. Because each stackable guide references the same fixation framework, the spatial relationship established during digital planning is preserved throughout the surgical workflow.⁵ This modular design allows different guides to be sequentially placed and removed during the procedure, each serving a specific function in the surgical and restorative sequence.

Base frame
The base frame can be fabricated from either metal or resin and the base frame serves as the indexing foundation for sequential guide components. The base frame is accurately attached to the bone by the positioning guide, and it can also act as the bone reduction guide, as will be demonstrated in the case presentation.

Positioning guide
To ensure stability and accuracy during the drilling process, implant placement and placement of the restorative components, the base frame needs to be delivered to the bone with a high degree of precision. The base frame is attached to the positioning guide outside of the mouth with various mechanisms. If teeth are present, the attached base frame and positioning guide are then seated over the teeth, allowing for horizontal holes to be drilled into the bone for the placement of anchor pins to secure the base frame to the bone. The positioning guide is then removed, leaving the base frame attached to the facial aspect of the maxillary or mandibular bone. Fully edentulous arches necessitate a well-fitting modified denture to act as a positioning guide seated firmly over the mucosal tissue and stabilised with a silicone maxillomandibular relationship record during the drilling of the horizontal holes for the anchor pins.

Bone reduction guide
In many full-arch implant cases, alveolar bone reduction is required to create adequate restorative space, establish a level platform for prosthetic reconstruction and provide the buccolingual width of bone necessary for implant placement.⁸ Early bone reduction guides existed as separate entities that were seated on to the bone, allowing access to the portion of bone to be removed. In stackable guide systems, the bone reduction guide is a visual and mechanical reference for the planned extent and contour of bone reduction and may be provided by the base frame itself. It is essential that the proper amount of bone is removed in the correct plane to correspond precisely to the restorative design and prosthetic space requirements determined during digital planning and to allow for complete seating of subsequent guides.

Osteotomy drill guides
After bone reduction, a drill guidance component is attached to the base frame to direct the sequential osteotomy preparation for implant placement. These guides often contain metal sleeves that control the trajectory, depth and spatial positioning of the drills.

The use of fixation-based indexing helps minimise deviations between the planned and actual implant positions.^{2, 3, 6} The osteotomy drill guide must correspond to the implant manufacturer’s guided drill kit, allowing the implants to be placed through the guide accurately into the bone. This approach, described as full-template guidance, reduces the risk of positional deviation during implant insertion.

Multi-unit abutment placement and timing guides
After implant placement, an additional guide may be used to assist with the placement and orientation of multi-unit abutments (MUAs). Proper positioning of MUAs is critical for achieving a passive fit of the prosthetic framework and ensuring appropriate restoration emergence profiles.

Prosthesis delivery or conversion guides
The final stage of many stackable workflows involves the delivery or conversion of an immediate provisional prosthesis. A prosthetic guide can assist in positioning temporary abutments on to the MUAs or prefabricated frameworks relative to the placed implants. Because the entire workflow is derived from the same digital treatment plan, the provisional prosthesis can often be fabricated in advance and delivered at the time of surgery, as will be illustrated in the case presentation.^{9, 7}

Fig. 3a: Intra-oral scan views of both arches demonstrating the severe malocclusion and narrow V-shaped arch form. Right lateral view.

Fig. 3b: Frontal view.

Fig. 3c: Left lateral view.

Fig. 3d: Occlusal view of the maxillary arch.

Fig. 3e: Oblique frontal view of the mandibular arch.

Fig. 4: Simulated implant plan on the panoramic radiograph, illustrating placement of five additional implants, in positions #16, 13, 11, 22 and 23, to achieve cross-arch stability for a full-arch implant-supported restoration.

Materials and manufacturing technologies

Depending on the intended function of each component, these guides may be produced using subtractive or additive methods and may incorporate resin, metal or hybrid constructions.

Milled resin guides
Subtractive manufacturing of PMMA or other dental resins provides highly accurate and rigid guides. Milled guides often exhibit excellent dimensional stability and surface quality.

3D-printed resin guides
Additive manufacturing using biocompatible photopolymer resins has become widely adopted for surgical guide fabrication. Advanced dental 3D printers can produce highly detailed guides with excellent accuracy and relatively rapid production times.

Metal-reinforced and fully metal guides
To enhance structural stability, some stackable guide systems incorporate metal components produced by 3D printing or casting, typically fabricated from titanium or cobalt–chromium alloys. These metal frameworks can improve rigidity and resistance to deformation during fixation and surgical manipulation.

Metal sleeves are frequently integrated into resin guides to maintain precise drill alignment during osteotomy preparation. In certain advanced systems, fully metal base frames are secured directly to the bone using fixation screws, providing an extremely stable foundation for subsequent stacked guides.

Case report: Maxillary arch treatment

A 66-year-old male presented with failing maxillary and mandibular teeth and a severe malocclusion (Figs. 1a & b). After years of repetitive patchwork and continued fractures, the patient was finally motivated by upcoming family events to fix his dentition. The initial CBCT-generated preoperative panoramic reconstruction showed the condition of the remaining teeth, four previously placed implants, posterior edentulous areas and an impacted tooth in the posterior of the right maxilla (Fig. 2).

A phased treatment plan was developed to address the maxillary and mandibular dentition. The patient accepted the treatment plan for full-mouth implant-supported prostheses developed to establish a new occlusal scheme, for a balanced functional and aesthetic outcome. The initial treatment commenced with a maxillary left posterior lateral sinus augmentation to create a foundation for future implants, not chronicled in this article. Once the bone graft had fully healed, the first series of implants were placed and a second series was placed thereafter, the latter of which is the focus of this case report.

Intra-oral scans of both arches (Aoralscan Elite, SHINING 3D) documented the malocclusion, asymmetry and narrow V-shaped arch form (Figs. 3a–e). After osseointegration of the previously placed maxillary left implants had been confirmed using resonance frequency analysis (Osstell), additional implants were planned for the maxillary arch to support a full-arch implant-supported prosthesis (Fig. 4). The pre-existing implants in the areas of the right premolars were evaluated in terms of bone levels, osseointegration and their ability to receive MUAs. The diagnostic process was assisted by segmentation of bone and teeth using artificial intelligence (AI) to better visualise the anatomical relationships of the arches (Figs. 5a–c).

Fig. 5a: Views of AI-assisted bone and tooth segmentation of the maxillary arch used for diagnosis, treatment planning and surgical guide design. Right lateral view.

Fig. 5b: Left lateral view.

Fig. 5c: Frontal view.

Fig. 6a: Use of selective transparency in the planning software to visualise the relationship between the crowns, roots and surrounding anatomical structures. Left lateral view.

Fig. 6b: Frontal view.

Fig. 6c: Right lateral view.

Using the selective transparency function in the interactive treatment planning software (Blue Sky Plan, Blue Sky Bio), the relationship between the existing crowns, roots and surrounding bone structures was visualized in 3D (Figs. 6a–c). This provided enhanced visualization of adjacent structures and supported clinical decision-making. Each potential implant receptor site was evaluated in all views afforded by the CBCT dataset, and the implants were simulated in positions to best support the desired restoration. Implant length and diameter were selected according to the requirements of the individual cross-sectional views (Figs. 7a–e). Screen captures were used to create still images annotated with the diameter and length of the proposed implants.

Fig. 7a: Cross-sectional views of the maxillary arch showing simulated implant positions and planned implant dimensions based on the CBCT scan data. Implant in position #16.

Fig. 7b: Implant in position #13.

Fig. 7c: mplant in position #11.

Fig. 7d: Implant in position #22.

Fig. 7e: Implant in position #23.

Figs. 8a–c: 3D segmentation of the maxilla illustrating the planned bone reduction (a) and implant positioning, indicated by yellow abutment projections (b & c).

Fig. 8b

Fig. 8c

Figs. 9a–c: Merging of the intra-oral scan dataset (a) with the CBCT reconstruction (b) to verify implant positioning (c) relative to the proposed prosthetic design.

Fig. 9b

Fig. 9c

Fig. 10a: Occlusal view of the segmented maxillary arch showing the planned implant positions and yellow abutment projections.

Fig. 10b: Occlusal view of the metal base frame attached to the maxillary model, resting on the posterior bone and soft tissue (yellow arrows).

The simulated implants were positioned within the alveolar bone according to the triangle of bone concept that I described in 1995.¹⁰ The plan for each implant also exhibited an abutment projection positioned to emerge within the envelope of the projected occlusal scheme. AI-assisted segmentation was essential to help plan and visualise the amount of crestal bone necessary to provide adequate ridge thickness for implant placement and restorative space for the MUAs to support the milled PMMA provisional prosthesis. It is important to note that the vertical positioning of each implant helped define the amount of bone reduction required. Therefore, following my recommended approach, all the implants were planned first and then the bone was reduced in accordance with their planned positions.

Using selective transparency, the planned amount of bone reduction could be visualised by superimposing 3D models of the maxillary bone before and after the planned bone reduction (Figs. 8a & b). Selective transparency allowed the planned implant positioning to be assessed in relation to the planned bone reduction (Fig. 8c). Once the initially placed maxillary left implants had received the corresponding MUAs, the digital workflow captured the intra-oral soft tissue and teeth via intra-oral scans, which were then exported to an STL file (Fig. 9a). The file was then imported into the planning software and the intra-oral scan data merged with the CBCT data (Fig. 9b). Overlaying the pre-existing intra-oral presentation on the maxillary bone allowed assessment of the trajectories of the proposed screw access holes relative to the proposed prosthetic position, supporting restoratively driven planning (Figs. 9c & 10a).

Prior to tooth extraction and bone reduction, the modular stackable workflow would begin with fixation of the base frame to the maxillary bone using a positioning guide (not shown). The metal base frame design contained distal saddles and ballpoint contacts that would rest on the bone or soft tissue (Fig. 10b; IBUR BioSystems). To verify that the bone reduction was sufficient, a combined bone reduction and timing jig would be attached to the base frame. The multi-purpose jig contained recessed markers indicating anti-rotational orientation to ensure that each implant would be precisely aligned for the corresponding MUA (Fig. 11a). The MUAs would be delivered through the timing jig (Fig. 11b).

Fig. 11a: Occlusal view of the bone reduction and timing jig seated on the base frame over the MUAs, showing recessed markers indicating implant rotational orientation.

Fig. 11b: Oblique lateral view showing attachment of the jig to the base frame.

The stackable system employed a slide-and-tilt design consisting of two components: the base frame with designated receptor rings and the osteotomy drill guide (Figs. 12a–c). In this design, the osteotomy drill guide slides horizontally into the posterior receptor rings on the base frame and tilts vertically into the anterior slot mechanism (Fig. 13). Once the osteotomy drill guide is seated, the locking pin is inserted to secure it in place (Figs. 14a & b).

Figs. 12a–c: Schematic representation of the maxillary bone (a), base frame (b) and osteotomy drill guide (c), illustrating the ballpoint contacts and posterior receptor rings.

Fig. 13: Engagement of the osteotomy drill guide with the base frame using the slide-and-tilt mechanism (orange arrows).

Fig. 14a: Anterior positive seat for the osteotomy drill guide provided by the slide-and-tilt mechanism.

Fig. 14b: Anterior positive seat for the osteotomy drill guide secured with a horizontal locking pin.

After osteotomy preparation, the implants would be placed in the maxillary bone and MUAs secured to the implants with the timing jig (Fig. 15a). Prior to closure of the surgical site, titanium cylinders would be tightened on to each MUA and the provisional prosthesis attached to the base frame (Figs. 15b & c). The titanium cylinders would then be connected to the provisional prosthesis using dual-polymerising acrylic resin injected through the occlusal access holes (STELLAR DC Acrylic, Taub Products).

Fig. 15a: Simulated prosthetic workflow. Occlusal view of the planned implants and MUAs with the base frame.

Fig. 15b: Lateral view of the provisional prosthesis seated on the base frame.

Fig. 15c: Occlusal view showing the simulated titanium cylinders (yellow) emerging through the provisional prosthesis.

“The concept of stackable surgical guides has transitioned from experimental digital workflows into clinically validated systems.”

Surgical intervention

Because intubation was contra-indicated, the surgical procedure was completed under sedation administered by an anaesthesiologist rather than under general anaesthesia. The modular components as previously described were cold sterilised prior to use and assembled. The base frame was attached to the positioning guide using the receptor rings and the locking pin. After local infiltration of 2% lidocaine with 1:100,000 adrenaline, the maxillary first and second molars were extracted. A full-thickness mucoperiosteal flap was raised from the right posterior to left posterior molar regions.

The combination of the positioning guide and the base frame was placed over the remaining maxillary teeth (Fig. 16). A 2 mm drill was used to prepare small-diameter osteotomies for the anchor pins, which were then inserted to secure the base frame to the maxillary bone. Once the base frame was secure, the anterior locking pin and the positioning guide were removed, leaving the base frame in place. All the remaining maxillary teeth were then carefully extracted, preserving the facial cortical plates. Bone reduction was completed with a large rongeur and an angled ^1:2 surgical handpiece (S-16, W&H) fitted with straight surgical burs from the Meisinger Alveoplasty Surgical Kit (Meisinger; Figs. 17 & 18).

Once the desired bone reduction had been verified, the keyless, sleeveless osteotomy drill guide was secured to the base frame using the slide-and-tilt mechanism. Precision osteotomies were then prepared as planned through the resin guide using sequential wide-shank drills from the manufacturer’s guided drill kit (Neo NaviGuide kit, Neobiotech; Figs. 19a & b) without keys or cylinders to ensure the precision and accuracy of each osteotomy preparation (Fig. 20). Using guided implant mounts, the implants were delivered through the guide in the planned rotational position of each implant. Vertical anchors attached to the implants were used to provide additional guide stabilisation (Fig. 21).

Once all the implants had been placed, the MUAs and subsequent titanium cylinders were secured to each implant. Small dental dam ovals were then slid over each titanium cylinder to protect the surgical site. The provisional prosthesis was attached to the base frame over the titanium cylinders (Figs. 22a & b). The dual-polymerising acrylic resin was then injected through the occlusal holes, surrounding the titanium cylinders. The prosthesis was then removed, the titanium cylinders cut back as needed, and any voids were filled with acrylic and polished. All extraction sockets and fenestrations and concavities on the facial aspect were then filled with saline-hydrated mineralised cortico-cancellous bone grafting material (250–1,000 μm particle size) extruded through a syringe (TBS Allograft Bone in a Syringe, TBS Dental; Fig. 23).

Fig. 16: Retracted intra-oral view of the surgical site with the positioning guide placed over the remaining teeth and the base frame attached.

Fig. 17: Retracted intra-oral view after tooth extraction and bone reduction, showing the base frame secured to the maxillary bone with the anchor pins (yellow arrows) and the bone reduction and timing jig attached to the frame.

Fig. 18: Retracted intra-oral view after removal of the bone reduction and timing jig, showing the two pre-existing maxillary implants (yellow arrows) and the gauze throat packing (green arrow), indicating possible interference with positioning of the modular guide system components.

Figs. 19a & b: Neo NaviGuide guided surgery system (a), demonstrating the wide-shank drill design (b) that allows keyless and sleeveless osteotomy preparation.

Fig. 20: Guided osteotomy preparation performed through the surgical guide attached to the base frame.

Fig. 21: Implant placement according to full-template guidance. Vertical anchor (yellow arrow) attached to improve guide stability.

Fig. 22a: Retracted intra-oral oblique occlusal view of the provisional prosthesis attached to the base frame over the titanium cylinders.

Fig. 22b: Retracted intra-oral facial view of the connection between the base frame and prosthesis.

Fig. 23: Filling of the extraction sockets and fenestrations and concavities on the facial aspect with mineralised bone grafting material after removal of the provisional prosthesis.

Discussion

The concept of stackable surgical guides has transitioned from experimental digital workflows into clinically validated systems offered by specialised dental laboratories and digital planning platforms.⁵

Several commercial technologies have contributed to the adoption and refinement of this approach to full-arch implant rehabilitation. Stackable guides offer several clinical advantages. These include:

improved surgical accuracy through stable fixation and indexed guide system components;
enhanced integration of surgical and restorative workflows;
reduced surgical time in many cases;
facilitation of immediate loading protocols;
improved predictability of prosthetic fit; and
compatibility with extra-oral or intra-oral photogrammetry protocols.

This case presentation has demonstrated a novel stackable design concept developed by IBUR BioSystems, one of the early contributors to modular guided surgery systems, as part of its patented surgical guide technologies incorporating stackable guide sets for diagnostic positioning, bone-borne guidance and prosthesis transfer jigs. These systems emphasise accurate data capture and the sequential transfer of the digital treatment plan from diagnostic imaging to surgical execution and prosthesis placement.

The features of the modular design demonstrated in this case presentation include:

a locking system enabling secure attachment of the guides using posterior slide-and-tilt receptor rings and a single anterior locking pin;
a slide-and-tilt mechanism designed to manage anatomical undercuts that would otherwise prevent proper guide orientation;
a slim and sturdy metal base frame;
a stable and verifiable fit of the base frame through strategically positioned ballpoint contacts on the posterior alveolar ridge and lateral surface of the jawbone;
reduced reliance on multiple fixation sites to secure the base frame; and
an extraction sequence in which posterior teeth were removed first to facilitate subsequent extractions and minimise potential interference.

However, stackable guides also have several limitations.

These include:

increased complexity of digital planning and guide design;
higher fabrication costs compared with conventional guides;
the need for laboratory support during the surgical procedure;
dependence on precise imaging and digital data registration;^{2, 3}
potential for cumulative error if indexing mechanisms are improperly designed;^{2, 3, 6} and
spatial challenges when seating guide system components in sedated or intubated patients owing to gauze packing and forward tongue positioning.

Despite these considerations, stackable guide systems have become increasingly valuable for immediate loading in full-arch implant rehabilitation cases.^{4, 5, 8}

Conclusion

Stackable surgical guides represent an important advancement in guided implant surgery, particularly in the treatment of edentulous patients undergoing full-arch reconstruction with immediate loading protocols.^{4, 5}

By providing a modular sequence of indexed guides attached to a stable base frame, these systems enable clinicians to perform bone reduction, osteotomy preparation, implant placement, abutment positioning and provisional prosthesis delivery within a coordinated surgical and restorative workflow.

This integration of surgical and prosthetic procedures represents a major advancement compared with earlier static surgical guides that primarily directed osteotomy preparation. The slide-and-tilt design described here provides an alternative stackable guide approach that may facilitate guide positioning in anatomically challenging situations.

Advances in digital imaging and CAD/CAM manufacturing—including resin materials for milling, polymer materials for 3D printing and metal framework fabrication—have enabled the development of increasingly precise and stable guide systems.^{1, 2} As digital implant workflows continue to evolve, stackable surgical guides are likely to play an increasingly important role in improving the efficiency, accuracy and predictability of full-arch implant reconstruction.

Editorial note:

The list of references can be found here. This article was published in digital—international magazine of digital dentistry vol.7, issue 1/2026.