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A surgical guide for dental implant placement in an edentulous jaw
A surgical guide for dental implant placement in an edentulous jaw Peter Y. P. Wat, BDS,a Edmond H. N. Pow, BDS, MDS, PhD,b Francis S.W. Chau, BDS, MDS,c and Katherine C.M. Leung, BDS, MDS, PhDd Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, People’s Republic of China The success of implant therapy greatly depends on placing dental implants in the optimum position and angulation during surgery. Different types of surgical guides have been advocated.1-7 Stability of the surgical guide is crucial during implant placement. Most of the guides are positioned intraorally by resting them on the teeth adjacent to the implant site. However, it is difficult to position the guide in edentulous jaws or when patients have limited remaining teeth. Some authors have suggested using bone anchor pins or transitional implants in such clinical situations.6 However, anchoring devices are costly and the procedure poses further surgical trauma to the patient. The surgical guide described is stable during surgery due to cross-arch fixation. It also serves as a mouth prop to stabilize the jaw and minimize the patient’s strain during surgery. Compared with anchor pins and transitional implants, this technique is more convenient, economical, and less traumatic for the patient. It can be used with any implant system and only minimal materials and components are required. Nevertheless, this technique may be contraindicated if the opposing jaw is also edentulous or does not have sufficient remaining teeth. There may also be a possibility of shifting of the
guide in patients with uncontrolled mandibular movements. A technique for fabricating a surgical guide for an edentulous jaw that can be positioned and secured by using the remaining dentition of the opposing arch is described.
PROCEDURE 1. Make irreversible hydrocolloid (Aroma Fine DF; GC Corp, Tokyo, Japan) impressions of the maxillary and mandibular arches and form diagnostic casts. 2. Fabricate maxillary and mandibular radiographic templates by duplicating the maxillary and mandibular dentures using autopolymerizing acrylic resin (Orthocryl EQ; Dentaurum, Ispringen, Germany) mixed with barium sulfate at a ratio of 4:1 (Fig. 1, A). 3. Mount the maxillary template with the maxillary cast on the survey table of a milling machine (Metalor Technologies SA, Neuchâtel, Switzerland). Make cylindrical channels, 2.0 mm in diameter, at the proposed implant sites on the template, and place the template intraorally before making the computed tomography (CT) scan. 4. Fabricate maxillary and mandibular record bases (Vertex Tray-
Honorary Associate Professor, Oral Rehabilitation. Associate Professor, Oral Rehabilitation. c Part-time Lecturer, Oral Rehabilitation. d Assistant Professor, Oral Rehabilitation. a
b
(J Prosthet Dent 2008;100:323-325)
Wat et al
plast; Vertex-Dental BV, Zeist, The Netherlands) with wax rims (Truwax; Dentsply Intl, York, Pa) on the casts. 5. Make a maxillomandibular relationship record of the centric relation position using the record bases and wax (Truwax; Dentsply Intl) with the patient’s mouth open to approximately 30 mm. Mount the casts in a semiadjustable articulator (Dentatus Articulator ARH type; Dentatus AB, Stockholm, Sweden). 6. Determine the location and orientation of the definitive implant sites from the CT scan images, as described previously.7 Duplicate the maxillary radiographic template to make a surgical guide, and fabricate a mandibular record base using clear autopolymerizing resin (Orthocryl EQ; Dentaurum). Remove the teeth from the guide using an acrylic bur (#251; HJ Bosworth, Skokie, Ill) with a straight handpiece (945; W & H Dentalwerk Burmoos GmbH, Burmoos, Austria). 7. Place the maxillary surgical guide and the cast on the survey table of the milling machine. Adjust the survey table to the appropriate orientation with the help of 2 spirit levels (Niigata Seiki Co, Ltd, Niigata, Japan), and make cylindrical channels at the definitive implant sites on the surgical guide with a 2.0-mm-diame-
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Volume 100 Issue 4
B
A
C 1 A, Maxillary and mandibular radiographic templates. B, Maxillary surgical guide mounted on milling machine. C, Surgical guide for placement of 6 implants in maxilla connected to mandibular record base on mounted casts.
A
B
2 A, Maxillary surgical guide and mandibular record base assembled in place. B, Definitive implant-supported fixed maxillary complete and mandibular partial dentures. ter cylindrical drill (Edenta AG, Au/St. Gallen, Switzerland) attached to the milling machine (Fig. 1, B).7 8. Place the maxillary surgical guide and mandibular record base on the mounted casts and connect them together by embedding 3.0-mm-diameter stainless steel rods (KC Smith and Co; Monmouth, UK) and 3.15mm-diameter tubes (KC Smith and Co) into the mandibular and maxil-
lary guides, respectively (Fig. 1, C). 9. During surgery, assemble the surgical guide with the record base intraorally (Fig. 2, A), and prepare implant sites using the surgical guide. Note the intraoral view demonstrating proper implant placement and the definitive implant-supported fixed maxillary complete and mandibular partial dentures (Fig. 2, B).
The Journal of Prosthetic Dentistry
REFERENCES 1. Arfai NK, Kiat-Amnuay S. Radiographic and surgical guide for placement of multiple implants. J Prosthet Dent 2007;97:310-2. 2. Atsu SS. A surgical guide for dental implant placement in edentulous posterior regions. J Prosthet Dent 2006;96:129-33. 3. Shotwell JL, Billy EJ, Wang HL, Oh TJ. Implant surgical guide fabrication for partially edentulous patients. J Prosthet Dent 2005;93:294-7.
Wat et al
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October 2008 4. Akça K, Iplikçioglu H, Cehreli MC. A surgical guide for accurate mesiodistal paralleling of implants in the posterior edentulous mandible. J Prosthet Dent 2002;87:233-5. 5. Becker CM, Kaiser DA. Surgical guide for dental implant placement. J Prosthet Dent 2000;83:248-51.
6. Simon H. Use of transitional implants to support a surgical guide: enhancing the accuracy of implant placement. J Prosthet Dent 2002;87:229-32. 7. Wat PY, Chow TW, Luk HW, Comfort MB. Precision surgical template for implant placement: a new systematic approach. Clin Implant Dent Relat Res 2002;4:88-92.
Corresponding author: Dr Edmond H.N. Pow Oral Rehabilitation Faculty of Dentistry University of Hong Kong 34 Hospital Road HONG KONG Fax: 852-2858 6114 E-mail: [email protected] Copyright © 2008 by the Editorial Council for The Journal of Prosthetic Dentistry.
Noteworthy Abstracts of the Current Literature Quantitative clinical evaluation of esthetic properties of incisors Ardu S, Feilzer AJ, Devigus A, Krejci I. Dent Mater 2008;24:333-40. Objective: To match perfectly the optical properties of natural teeth, a scientific approach is needed by using digital technology that excludes bias to quantitatively characterize the optical properties of populations’ teeth. The aim of this article is to present a method for a detailed clinical quantification of optical properties of front teeth. Methods: A novel spectrophotometric approach was developed and applied on a preliminary group of subjects quantifying L* (luminosity), a* (quantity of green-red) and b* (quantity of blue-yellow) of enamel and enamel-dentin complex against black and white background. Based on these in vivo data, CR (opacity) and opalescence (the ability to reflect blue wavelength when white light stroke the object perpendicularly) were also calculated. Results: The mean values of L* of the enamel-dentin complex against black and white background were 79.6 and 75.4, respectively. The mean values of a* were 2.5 against black and 0.8 against white background, respectively. The mean values of b* were 17.4 against black and 13.0 against white background, respectively. The mean contrast ratio was 86.7%. Opalescence value was 4.8. The mean values of L* of enamel against black and white background were 79.0 and 64.2, respectively. The mean values of a* were 2.1 against black and -0.3 against white background, respectively. The mean values of b* were 15.2 against black and 8.7 against white background, respectively. The mean contrast ratio was 60.5%. Opalescence value was 7.4. Significance: The described methodology, applied on a larger group of subjects, may serve as a database for a more exact characterization of optical properties of natural enamel and dentin. Reprinted with permission of the Academy of Dental Materials.
Wat et al
guide in patients with uncontrolled mandibular movements. A technique for fabricating a surgical guide for an edentulous jaw that can be positioned and secured by using the remaining dentition of the opposing arch is described.
PROCEDURE 1. Make irreversible hydrocolloid (Aroma Fine DF; GC Corp, Tokyo, Japan) impressions of the maxillary and mandibular arches and form diagnostic casts. 2. Fabricate maxillary and mandibular radiographic templates by duplicating the maxillary and mandibular dentures using autopolymerizing acrylic resin (Orthocryl EQ; Dentaurum, Ispringen, Germany) mixed with barium sulfate at a ratio of 4:1 (Fig. 1, A). 3. Mount the maxillary template with the maxillary cast on the survey table of a milling machine (Metalor Technologies SA, Neuchâtel, Switzerland). Make cylindrical channels, 2.0 mm in diameter, at the proposed implant sites on the template, and place the template intraorally before making the computed tomography (CT) scan. 4. Fabricate maxillary and mandibular record bases (Vertex Tray-
Honorary Associate Professor, Oral Rehabilitation. Associate Professor, Oral Rehabilitation. c Part-time Lecturer, Oral Rehabilitation. d Assistant Professor, Oral Rehabilitation. a
b
(J Prosthet Dent 2008;100:323-325)
Wat et al
plast; Vertex-Dental BV, Zeist, The Netherlands) with wax rims (Truwax; Dentsply Intl, York, Pa) on the casts. 5. Make a maxillomandibular relationship record of the centric relation position using the record bases and wax (Truwax; Dentsply Intl) with the patient’s mouth open to approximately 30 mm. Mount the casts in a semiadjustable articulator (Dentatus Articulator ARH type; Dentatus AB, Stockholm, Sweden). 6. Determine the location and orientation of the definitive implant sites from the CT scan images, as described previously.7 Duplicate the maxillary radiographic template to make a surgical guide, and fabricate a mandibular record base using clear autopolymerizing resin (Orthocryl EQ; Dentaurum). Remove the teeth from the guide using an acrylic bur (#251; HJ Bosworth, Skokie, Ill) with a straight handpiece (945; W & H Dentalwerk Burmoos GmbH, Burmoos, Austria). 7. Place the maxillary surgical guide and the cast on the survey table of the milling machine. Adjust the survey table to the appropriate orientation with the help of 2 spirit levels (Niigata Seiki Co, Ltd, Niigata, Japan), and make cylindrical channels at the definitive implant sites on the surgical guide with a 2.0-mm-diame-
324
Volume 100 Issue 4
B
A
C 1 A, Maxillary and mandibular radiographic templates. B, Maxillary surgical guide mounted on milling machine. C, Surgical guide for placement of 6 implants in maxilla connected to mandibular record base on mounted casts.
A
B
2 A, Maxillary surgical guide and mandibular record base assembled in place. B, Definitive implant-supported fixed maxillary complete and mandibular partial dentures. ter cylindrical drill (Edenta AG, Au/St. Gallen, Switzerland) attached to the milling machine (Fig. 1, B).7 8. Place the maxillary surgical guide and mandibular record base on the mounted casts and connect them together by embedding 3.0-mm-diameter stainless steel rods (KC Smith and Co; Monmouth, UK) and 3.15mm-diameter tubes (KC Smith and Co) into the mandibular and maxil-
lary guides, respectively (Fig. 1, C). 9. During surgery, assemble the surgical guide with the record base intraorally (Fig. 2, A), and prepare implant sites using the surgical guide. Note the intraoral view demonstrating proper implant placement and the definitive implant-supported fixed maxillary complete and mandibular partial dentures (Fig. 2, B).
The Journal of Prosthetic Dentistry
REFERENCES 1. Arfai NK, Kiat-Amnuay S. Radiographic and surgical guide for placement of multiple implants. J Prosthet Dent 2007;97:310-2. 2. Atsu SS. A surgical guide for dental implant placement in edentulous posterior regions. J Prosthet Dent 2006;96:129-33. 3. Shotwell JL, Billy EJ, Wang HL, Oh TJ. Implant surgical guide fabrication for partially edentulous patients. J Prosthet Dent 2005;93:294-7.
Wat et al
325
October 2008 4. Akça K, Iplikçioglu H, Cehreli MC. A surgical guide for accurate mesiodistal paralleling of implants in the posterior edentulous mandible. J Prosthet Dent 2002;87:233-5. 5. Becker CM, Kaiser DA. Surgical guide for dental implant placement. J Prosthet Dent 2000;83:248-51.
6. Simon H. Use of transitional implants to support a surgical guide: enhancing the accuracy of implant placement. J Prosthet Dent 2002;87:229-32. 7. Wat PY, Chow TW, Luk HW, Comfort MB. Precision surgical template for implant placement: a new systematic approach. Clin Implant Dent Relat Res 2002;4:88-92.
Corresponding author: Dr Edmond H.N. Pow Oral Rehabilitation Faculty of Dentistry University of Hong Kong 34 Hospital Road HONG KONG Fax: 852-2858 6114 E-mail: [email protected] Copyright © 2008 by the Editorial Council for The Journal of Prosthetic Dentistry.
Noteworthy Abstracts of the Current Literature Quantitative clinical evaluation of esthetic properties of incisors Ardu S, Feilzer AJ, Devigus A, Krejci I. Dent Mater 2008;24:333-40. Objective: To match perfectly the optical properties of natural teeth, a scientific approach is needed by using digital technology that excludes bias to quantitatively characterize the optical properties of populations’ teeth. The aim of this article is to present a method for a detailed clinical quantification of optical properties of front teeth. Methods: A novel spectrophotometric approach was developed and applied on a preliminary group of subjects quantifying L* (luminosity), a* (quantity of green-red) and b* (quantity of blue-yellow) of enamel and enamel-dentin complex against black and white background. Based on these in vivo data, CR (opacity) and opalescence (the ability to reflect blue wavelength when white light stroke the object perpendicularly) were also calculated. Results: The mean values of L* of the enamel-dentin complex against black and white background were 79.6 and 75.4, respectively. The mean values of a* were 2.5 against black and 0.8 against white background, respectively. The mean values of b* were 17.4 against black and 13.0 against white background, respectively. The mean contrast ratio was 86.7%. Opalescence value was 4.8. The mean values of L* of enamel against black and white background were 79.0 and 64.2, respectively. The mean values of a* were 2.1 against black and -0.3 against white background, respectively. The mean values of b* were 15.2 against black and 8.7 against white background, respectively. The mean contrast ratio was 60.5%. Opalescence value was 7.4. Significance: The described methodology, applied on a larger group of subjects, may serve as a database for a more exact characterization of optical properties of natural enamel and dentin. Reprinted with permission of the Academy of Dental Materials.
Wat et al