|Year : 2014 | Volume
| Issue : 1 | Page : 78-81
One for all: A multipurpose template for implant placement
Rathinkumar D Das, Makarand Vijay Deshpande, Renu Kaushal
Department of Prosthodontics, Y.M.T Dental College and Hospital, Kharghar, Navi Mumbai, Maharashtra, India
|Date of Web Publication||19-Apr-2014|
Rathinkumar D Das
Department of Prosthodontics, Y.M.T Dental College and Hospital, Kharghar, Navi Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
| Abstract|| |
A method is presented describing the laboratory fabrication and clinical use of an innovative template. This template was designed to function as a radiographic implant positioning guide, accurate bone sounding guide, surgical guide, an aid in flap reflection and as a pick-up impression tray.
Keywords: Multipurpose implant template, pick-up impression tray, radiographic guide, surgical guide, transgingival probing guides
|How to cite this article:|
Das RD, Deshpande MV, Kaushal R. One for all: A multipurpose template for implant placement. J Dent Implant 2014;4:78-81
| Introduction|| |
The success of an implant supported restoration relies on the proper implant body placement. The parallelism and proper buccal and lingual placement of endosseous implants are important if the clinician is to produce a functional and esthetic prosthesis. ,
Precise planning for implant placement is dependent to a great extent on accurate pre-operative information about the bony topography of the implant site. Currently, the computerized tomogram (CT) and cone beam computed tomography (CBCT) are available for cross-sectional pre-operative planning.  However, these imaging methods may not be readily available to the clinician and their costs may be prohibitive to the patient.
Possible alternatives to CT and CBCT include conventional radiography and transgingival bone sounding, which have been shown to provide a correlation between presurgical and surgical measurements. ,,, Used individually, these two methods provide less information than a CT and CBCT, but when combined they can provide the clinician with a three dimensional picture of the implant site. To maximize these benefits, both techniques require the fabrication of a template.  In addition, precise surgical implant placement requires template guidance. However, the generation of up to four guides during the course of implant treatment could be costly with respect to time and laboratory fees.
An innovative approach to implant treatment planning has been developed to assign multiple tasks to a single template. This template is designed to function as:
- A radiographic implant positioning guide,
- Accurate bone sounding guide,
- Surgical guide,
- An aid in flap reflection and,
- An impression tray to provide an immediate pick-up impression subsequent to implant placement.
| Fabrication Technique|| |
- Three accurate stone casts are to be made. One of these will be used to process the template
- All undercuts and occlusal surface details are blocked out using mounting stone
- Orthodontic wire clasps are placed mesially and distally to edentulous sites for additional retention
- The template is waxed with conventional base - plate wax and extensions ("wings") are placed extending to the depth of the vestibule buccally and to the palatal suture line medially
- Denture teeth are used to determine the position of the final restoration
- The waxed template is then processed in clear acrylic resin to allow for improved surgical visualization [Figure 1].
- A small diameter round bur, corresponding in size to the diameter of a periodontal probe, is used to drill a series of guide holes in the acrylic resin on the buccal and palatal/lingual aspects of the template [Figure 2]
- The template is adjusted intraorally and transgingival bone sounding accomplished to provide information on the bony topography of the proposed implant sites [Figure 3]
- The measurements are transferred to the second diagnostic cast, which are sectioned in the planes corresponding to the set holes on the template for each implant site [Figure 4]. Thus ridge mapping is obtained
- The Die-lock system is used to ensure accurate reapproximation of the cast
- A 2.2 mm diameter bur in a milling machine is used to bore holes in the occlusal surface of each denture tooth. These holes corresponded to the desired location and angulation of the implants. A micro surveyor assists in this
- This 2.2 mm diameter corresponds to the diameter of the pilot drill in the implant system to be used
- Three metal sleeves of 2.2 mm diameter are placed into the guide holes allowing panoramic radiographic confirmation of implant angulations [Figure 5] and [Figure 6]
- Once the surgical preparation is done the metal sleeves on the template removed and the template used to guide the pilot drill for creating precise osteotomy sites [Figure 7]. The wings (extensions) of the template assist to reflect the flap during osteotomy [Figure 8]
- Once the osteotomy sites are prepared, the implants are placed
- While the surgery is in progress, the template is modified by removing the lateral wings and widening the guide holes on the occlusal surface
- The pick-up impression posts are placed on the implants with the care being taken not to disturb the orientation of the implants
- The modified template is then replaced intraorally with the impression posts protruding through the occlusal surfaces [Figure 9]
- Pattern resin is used to secure the posts to the template. Once the resin sets the template is removed and returned to the laboratory [Figure 10].
- In the laboratory the third cast is modified by preparing a large hole in the alveolar ridge at the implant site
- Implant analogs are screwed in to the impression copings in the template and wax is added to develop an emergence profile for the restoration
- The template is then placed on the cast so that no portion of the posts, or of the analogs, contacts the sides of the prepared cast
- Mounting stone is poured in from the underside and allowed to set
- The template is then removed leaving the implant analogs in position
- The stone cast is then mounted on an articulator and provisional restorations are waxed against the opposing arch
- The provisional restorations will be fabricated for second stage surgery.
| Discussion|| |
The technique described presents an innovative approach to the design of a device, which incorporates multiple guides into one template.
Although this template provided many uses, there were inherent limitations which had to be overcome. The first problem was the bulk of acrylic resin utilized in making the "wings" of the template. It was difficult to visualize the guide marks on the implant drills even though the acrylic resin was clear. To avoid this problem, slots can be prepared in the template to allow drill placement from a buccal direction. These slots would also facilitated the flow of coolant from hand pieces with external irrigation systems.
Another limitation was the height of template due to the inclusion of cusps on the denture teeth which inhibited the drill to reach its full depth according to the requirements of the osteotomy.
There were also some notable advantages. The transgingival bone sounding carried out with the template allowed to make accurate, reproducible image. The design of this template allowed the clinician to accurately read the probe depth, even after probing multiple sites, due to the thickness of the material and its ability to shield blood and maintain visualization of the probe.
The impression made at the time of first stage surgery allowed the clinician to fabricate the provisional restorations by the second stage surgery, thus allowing for optimal healing of the peri-implant soft-tissue to obtain an ideal profile.
| Conclusion|| |
An innovative approach to implant treatment planning that allows implants to be ideally placed with maximum efficiency and minimal cost has been presented. Aside from the use of a customized appliance, namely a template, for radiographic diagnostics, other purposes were served. The combining of prosthetic direction and surgical placement assured the clinical implant team that the subsequent procedures would be accurate and effective.
| References|| |
|1.||Quinlan P, Richardson CR, Hall EE. A multipurpose template for implant placement. Implant Dent 1998;7:113-21. |
|2.||Sykaras N, Woody RD. Conversion of an implant radiographic template into a surgical template. J Prosthodont 2001;10:108-12. |
|3.||Benson BW. Diagnostic imaging for dental implant assessment. Tex Dent J 1995;112:37-41. |
|4.||Todd AD, Gher ME, Quintero G, Richardson AC. Interpretation of linear and computed tomograms in the assessment of implant recipient sites. J Periodontol 1993;64:1243-9. |
|5.||Ursell MJ. Relationships between alveolar bone levels measured at surgery, estimated by transgingival probing and clinical attachment level measurements. J Clin Periodontol 1989;16:81-6. |
|6.||Ben-Yehouda A, Machtei EE. Sounding depth measurements: A method for evaluating various surgical techniques. J Periodontol 1991;62:565-9. |
|7.||Greenberg J, Laster L, Listgarten MA. Transgingival probing as a potential estimator of alveolar bone level. J Periodontol 1976;47:514-7. |
|8.||Easley JR. Methods of determining alveolar osseous form. J Periodontol 1967;38:112-8. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10]