|Year : 2018 | Volume
| Issue : 1 | Page : 37-39
Implant and prosthetic planning using cone beam computed tomography and radiographic markers for full mouth-fixed implant-supported prosthesis: A technique
Tushar Ranjan, Makam Gangaiah, Avadhesh K Chaubey, Isha Wadhwa, Kunal Nischal
Department of Prosthodontics Crown and Bridge, Rajarejeshwari Dental College and Hospital, Bengaluru, Karnataka, India
|Date of Web Publication||25-Jul-2018|
Dr. Tushar Ranjan
Department of Prosthodontics Crown and Bridge, Rajarejeshwari Dental College and Hospital, #14 Ramohalli Cross, Mysore Road, Bengaluru - 560 074, Karnataka
Source of Support: None, Conflict of Interest: None
| Abstract|| |
A fixed implant-supported full mouth prosthesis has been a routine treatment plan for completely edentulous patients. A systematic planning is must for successful implant placement and restoration. This article describes a technique to form a bridge between implant planning and execution of the plan using radiographic markers and cone beam computed tomography.
Keywords: All-on-4, cone beam computed tomography planning, lead foil, prosthesis tissue junction, radiographic marker
|How to cite this article:|
Ranjan T, Gangaiah M, Chaubey AK, Wadhwa I, Nischal K. Implant and prosthetic planning using cone beam computed tomography and radiographic markers for full mouth-fixed implant-supported prosthesis: A technique. J Dent Implant 2018;8:37-9
|How to cite this URL:|
Ranjan T, Gangaiah M, Chaubey AK, Wadhwa I, Nischal K. Implant and prosthetic planning using cone beam computed tomography and radiographic markers for full mouth-fixed implant-supported prosthesis: A technique. J Dent Implant [serial online] 2018 [cited 2019 Dec 9];8:37-9. Available from: http://www.jdionline.org/text.asp?2018/8/1/37/237587
| Introduction|| |
Improved surgical and prosthodontic treatment protocols including prosthetic design and materials have resulted in the increased popularity of maxillary fixed implant-supported prosthesis.
Cone beam computed tomography (CBCT) could be used effectively in imaging for treatment planning. Radiographic markers or guides exist to provide information regarding the proposed implant placement, the positioning of future prosthesis, soft-tissue thickness, and amount of bone reduction often necessary to either gain prosthetic space or to conceal the prosthetic tissue junction.,
In fixed implant-supported therapy, prosthesis tissue junction (PTJ) is not visible during patients' maximum smile because of inability to accurately match the color of prosthetic gingiva with natural gingiva/mucosal tissue.
In fabrication of radiographic guides, a number of radiopaque material have been used including gutta percha, barium sulphate, radiopaque putties, and metal such as amalgam and steel.
This article presents a technique for fabricating a guide that can be used both as radiographic and surgical guide in completely edentulous jaw by using lead sheets from IOPAR sleeve, which is commonly available in dental clinic.
| Technique|| |
Complete denture is fabricated using conventional method.
Steps to determine the following are as follows:
- To determine PTJ
- To determine prosthesis space
- To determine soft-tissue thickness
- To determine implant placement using denture's landmark.
To determine prosthesis tissue junction
- Insert the denture in patient's mouth and ask patient to smile and mark the high smile line with the help of marker on denture [Figure 1]
- Cut the lead foil into thin strips (1 mm) width and stick it on to the marked smile line on the denture with the help of adhesive [Figure 2]
- This line can be visualized in CBCT [Figure 3]. PTJ should be 4–5 mm above smile line.,
|Figure 3: Smile line can be visualized in cone beam computed tomography, and prosthesis tissue junction can be determined (green – prosthesis tissue junction location above smile line; orange – prosthetic space from incisal edge to bone; pink – prosthetic space from screw access hole to bone; yellow – soft-tissue thickness to determine abutment collar height)|
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To determine prosthetic space
- Cut the lead foil into thin strip (1 mm) width and stick it onto the incisal edges and occlusal surface of denture teeth using adhesive and adapt nicely using ball burnisher instrument [Figure 4]
- This line can be visualized in CBCT in panoramic view and cross-sectional view. Optimal prosthetic space should be at least 17 mm from maxillary incisal edge to bone  [Figure 3].
|Figure 4: One millimeter strip is stuck on occlusal and incisal surfaces of the upper and incisal surfaces of the lower|
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To determine the soft-tissue thickness
- Cut the lead foil into thin strip (1 mm) width and stick it on the intaglio surface of the denture's ridge crest with the help of adhesive and adapt it well using ball burnisher instrument [Figure 5]
- This line can be visualized in CBCT, and the distance between this line and crest of bone will give soft-tissue thickness which will help in determining the collar height of multiunit abutments [Figure 3].
|Figure 5: One millimeter thick strip is stuck on the intaglio surface of the maxillary and mandibular denture in crestal region|
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To determine implant placement using denture's landmark
- Cut the lead foil into thin strip (5 mm) width and adapt it labiolingually such that anteriorly, it should cover the midline of lateral incisor, and posteriorly, it should be such that it should cover the junction of 2nd premolar and 1st molar [Figure 2] and [Figure 4]
- This line can be visualized in CBCT in panoramic view and can be used as landmark to plan implant placement. In cross-section view, we can visualize the implant, bone, and prosthesis relationship. Prosthetic space can be calculated [Figure 3] and [Figure 6].
|Figure 6: Panoramic view showing smile line marker, occlusal line marker, soft-tissue line marker, and landmarks for implant placement (occlusal wrap)|
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| Summary|| |
The described technique uses commonly available materials and does not need any extra duplicate denture and does not damage the existing denture and used as interim prosthesis for immediate loading case. Same denture can be used as radiographic and surgical guide. Markers serve as a landmark in implant planning and execution.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Bidra AS, Agar JR, Parel SM. Management of patients with excessive gingival display for maxillary complete arch fixed implant-supported prostheses. J Prosthet Dent 2012;108:324-31.
Bidra AS. Technique for systematic bone reduction for fixed implant-supported prosthesis in the edentulous maxilla. J Prosthet Dent 2015;113:520-3.
Chong J, Seong WJ, Conrad HJ. Lead foil technique for partially edentulous radiographic guide. J Prosthet Dent 2012;108:268-70.
Bidra AS. A technique for transferring a patient's smile line to a cone beam computed tomography (CBCT) image. J Prosthet Dent 2014;112:108-11.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]