Transition from a fixed implant dental prosthesis to an implant overdenture in an edentulous patient: A clinical report Bolouri Ali, DMD, DDSa and Venkatachalam Bhavani, DMD, MSb Texas A&M University Baylor College of Dentistry, Dallas, Texas The lack of planning before implant placement and restoration in edentulous patients can lead to a number of problems. Prosthodontists are often faced with the challenge of re-treating patients who have only recently been treated. Although many reports discuss retreatment by fabricating all new prosthetic components, few discuss salvaging parts of the patient’s existing prosthesis. This report details the treatment of an edentulous patient who presented with an implant-retained fixed dental prosthesis in the maxillary arch and no opposing prosthesis. The transition from an implant-retained fixed dental prosthesis to a removable implant- and tissue-supported overdenture that uses the patient’s existing computer-aided design/computeraided manufacturing milled titanium substructure is described. (J Prosthet Dent 2014;-:---) Dental implants offer a predictable means of rehabilitating edentulous patients.1,2 However, careful assessment, a sound diagnosis, and planning before treatment are crucial to ensure a successful outcome.3 Multiple surgical and restorative factors play a role in the treatment planning of implant restorations for the edentulous patient. Key restorative factors include a thorough examination of hard and soft tissues, an assessment of available restorative space, the need for lip support, the location of the occlusal plane, and the number, position, and angulation of the implants.3,4 Most edentulous patients prefer a fixed implant prosthesis to a removable one.5 However, lack of lip support, excessive facial cantilevering, problems with speech, and difficulty maintaining good oral hygiene are some of the hurdles often associated with implant-retained fixed dental prostheses.6 Removable prostheses, in contrast, are easily retrievable and esthetically pleasing, allow for the production of normal speech sounds (especially in the maxillary arch), and facilitate hygiene maintenance.7 One of the main determinants of the type of implant restoration for the edentulous patient is restorative space. Implantretained fixed dental prostheses and bar overdentures need a minimum of a
13 to 14 mm between the crest of the edentulous ridge and the occlusal plane, whereas overdentures retained by Locator attachments (Locator; Zest Anchors) require a minimum of 8.5 mm.8,9 Other factors in determining prosthetic success are implant location and angulation,10 both dependent on tooth position. Therefore, determining tooth position is a critical part of the diagnostic process. One of the best tools available to the clinician to aid in pretreatment assessment is the patient’s existing denture, which helps the dentist identify the patient’s preferences and assess expectations.11 If the patient presents with a well-fitting and esthetically pleasing existing complete denture prosthesis, it can often be duplicated and used as a radiographic and surgical guide for implant placement. However, if the existing prosthesis is unacceptable, a new interim prosthesis or diagnostic wax-up must be fabricated that can be evaluated in the patient’s mouth to assess esthetics and phonetics before surgery. Implant surgery that is performed without restorative diagnosis usually results in a prosthetic outcome that is less than optimal and, very often, an unsatisfied patient.12 This clinical report describes the management of an
Professor and Director, Removable Prosthodontics Department of Restorative Sciences. Assistant Professor, Department of Restorative Sciences.
b
Ali and Bhavani
unhappy patient who presented after the insertion of a definitive fixed prosthesis and emphasizes the importance of communication and planning before treatment.
CLINICAL REPORT A 68-year-old healthy white male presented for dental treatment. His chief complaint was, “I don’t like the way my front teeth look.” The patient’s dental history revealed that he had had his maxillary arch restored a few weeks previously at another dental office. Since the insertion of his maxillary prosthesis, the patient had noticed changes in his speech, especially during the production of sibilant sounds. His main concern, however, was the discolored right and left maxillary lateral incisors, where composite resin had been used to seal the implant screw access openings on the facial surface (Fig. 1). When questioned about his mandibular prosthesis, the patient stated that the original treatment plan included the fabrication of a mandibular prosthesis, but he did not know whether or when the mandibular arch was going to be restored. Before his current prosthesis, the patient reported wearing conventional maxillary and mandibular complete dentures.
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1 Preoperative smile. Note discolored composite resin covering screw access openings in regions of maxillary right and left lateral incisors and incisal edge positioning of maxillary teeth.
The patient’s medical history did not present any contraindications to dental treatment. Intraoral examination revealed a maxillary implant fixed complete denture (FCD) opposing an edentulous mandibular arch with 5 healing abutments (Nobel Biocare). Minimal space was noted between the maxillary occlusal plane and the mandibular ridge, indicating the lack of restorative space for a mandibular prosthesis. A panoramic radiograph showed 6 implants and a metal substructure with long screw access channels in the maxillary arch. The channels appeared to have been sealed with cotton pellets and composite resin. The composite resin was found to extend the entire length of the channels (Fig. 2). Given the lack of restorative space for a mandibular prosthesis due to encroachment of the interocclusal space by the current maxillary prosthesis and the patient’s dislike of the esthetics, a decision was made to remove the maxillary prosthesis. This was accomplished over 2 appointments. The 4 posterior screw access channels were accessed first, then the 2 anterior channels. The prosthesis was removed and healing abutments were placed. At this time, the unfavorable facial angulation of the anterior maxillary implants was clearly visible. Interim maxillary and mandibular complete
Issue
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2 Pretreatment panoramic radiograph. Note composite resin in screw access channels and minimal space present between occlusal openings of channels and mandibular healing abutments.
overdentures were fabricated and inserted. The placement of healing abutments on the implants allowed for additional support of the complete denture prosthesis and the use of a soft liner (Luci-Sof; Dentsply Intl) in areas of the dentures contacting the healing abutments that provided some frictional retention. The patient was satisfied with the esthetics and the ability to function with the new interim prostheses. The interim prostheses served to motivate the patient, were used to determine restorative space in both arches, and allowed the clinician adequate time to complete the definitive prostheses. After the available treatment options and their advantages and disadvantages were discussed with the patient, a decision was made to fabricate definitive implant-retained maxillary and mandibular overdentures. The main rationales for the treatment choice were the undesirable angulations of the anterior maxillary implants, the amount of restorative space available, and patient preference. The patient was comfortable with the idea of a removable prosthesis and extremely satisfied with his interim dentures. He did not want to add to the cost of treatment significantly and, given the recent problems with his FCD, did not want another fixed prosthesis.
The Journal of Prosthetic Dentistry
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To assess the maxillary metal substructure, removing the denture base acrylic resin and denture teeth was essential. This was accomplished by soaking the maxillary prosthesis in acetone (W.M. Barr & Co Inc) overnight (Fig. 3). The fit of the computer-aided design/computer-aided manufacturing (CAD/CAM) titanium bar was then assessed and was found to fit intimately and passively on the maxillary implants. To compensate for the labial inclination of the anterior maxillary implants and save the patient the cost of fabricating another bar, a decision was made to salvage the bar. The existing milled bar was modified. The amount of reduction was verified with the help of a putty index (President; Coltène/ Whaledent) of the patient’s new interim complete denture (Fig. 4). Maxillary and mandibular implant level impressions were made with polyvinyl siloxane impression material (Aquasil; Dentsply), and definitive casts were generated. Jaw relation records were completed, and maxillary and mandibular trial dentures were fabricated. The amount of space around the modified bar was again verified with a putty index of the wax trial dentures. Because the space was adequate for a bar overdenture in the maxilla, 4 female low-profile titanium laser bar attachments (Locator) were welded on the bar, 2 in the anterior and 2 in the
Ali and Bhavani
-
2014
3
3 Maxillary computer-aided design/computer-aided manufacturing metal substructure with acrylic resin dissolved with acetone. Note buccolingual width of bar before modification.
4 Silicone putty index to verify reduction. Note adequate space available facially and occlusally. Note change in bar dimension and presence of low profile Locator attachments.
5 A, B, Evaluation of modified bar. Note anteroposterior spread of attachments.
6 Postoperative smile. posterior aspect to maximize the anteroposterior spread (Fig. 5). Because the bar was also made of titanium, the attachments could be welded without
Ali and Bhavani
concerns regarding metal compatibility. The positioning of the female Locator components on the bar was accomplished with the help of a Locator
paralleling mandrel (Zest Anchors) and a dental surveyor. The female components were spot-welded onto the bar. The male processing assembly was then attached to the female component, and welding around the base of the female components was completed to ensure that the additional weld did not interfere with the seating of the male component on the female component. The welded areas were then smoothed and polished. The definitive wax-up was completed, and the overdentures were processed and inserted. The patient was seen for postinsertion appointments at 24 hours and 1 week after insertion. The patient was satisfied with both his maxillary and mandibular prostheses (Fig. 6).
4
Volume DISCUSSION This article describes the management of a patient after definitive therapy. The transition from a fixed implant-supported prosthesis to a removable implant- and tissue-supported prosthesis is not commonly seen in practice. The rationale for the choice of treatment in this situation was the need to compensate for the lack of restorative planning before implant surgery. In some patients, even after careful planning, implant positions and angulations are not ideal. The clinician must reevaluate and sometimes alter the direction of treatment after the implants are uncovered. In this patient, with his poorly angulated maxillary anterior implants, the dentist could have retained the prosthesis with only the 4 distal implants or used a material other than composite resin to seal the screw access hole to allow for easier retrievability. Although the number of implants in the maxilla and mandible in this patient were optimal for a fixed prosthesis, the lack of restorative space made this hard to achieve. To facilitate esthetically pleasing and functional restorations in both arches, a careful analysis of the amount of space available was required. Determining the location of the occlusal plane and maxillary incisal edge position was essential in ensuring that sufficient space was available for a
mandibular prosthesis. This was accomplished by analyzing the esthetics, phonetics, and occlusal vertical dimension. Once definitive tooth positions and the presence of adequate space for a bar overdenture in the maxilla had been determined with the help of the interim prosthesis, the existing CAD/CAM metal substructure was modified by the careful recontouring and welding of 4 attachments. The weldable titanium attachments were compatible with the titanium milled bar. This kept the cost of treatment to a minimum.
CONCLUSION Implant restorations in edentulous patients require careful planning and communication between the patient, restoring dentist, and surgeon. The definitive goal and the steps needed to achieve the best possible outcome should be visualized before treatment is even begun to ensure optimal esthetics and function.
-
Issue
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3. Handelsman M. Surgical guidelines for dental implant placement. Br Dent J 2006;201:139-52. 4. Stanford CM. Application of oral implants to the general dental practice. J Am Dent Assoc 2005;136:1092-100. 5. Zitzmann NU, Marinello CP. Treatment planning for restoring the edentulous maxilla with implant-supported restorations: removable overdenture versus fixed partial denture design. J Prosthet Dent 1999;82:188-96. 6. Lewis S, Sharma A, Nishimura R. Treatment of edentulous maxillae with osseointegrated implants. J Prosthet Dent 1992;68:503-8. 7. Heydecke G, Boudrias P. Within-subject comparisons of maxillary fixed and removable implant prostheses: patient satisfaction and choice of prosthesis. Clin Oral Implants Res 2003;14:125-30. 8. Sadowsky SJ. Treatment considerations for maxillary implant overdentures: a systematic review. J Prosthet Dent 2007;97:340-8. 9. Lee CK, Agar JR. Surgical and prosthetic planning for a two-implant-retained mandibular overdenture: a clinical report. J Prosthet Dent 2006;95:102-5. 10. Bidra AS, Agar JR. Management of misangulated implants for a maxillary overdenture with spherical abutments: a clinical report. J Prosthet Dent 2011;106:209-13. 11. Jivraj S, Chee W, Corrado P. Treatment planning of the edentulous maxilla. Br Dent J 2006;201:261-79; quiz 304. 12. Binon PP. Treatment planning complications and surgical miscues. J Oral Maxillofac Surg 2007;65(suppl 1):73-92.
REFERENCES 1. Adell R, Lekholm U, Rockler B, Brånemark PI. A 15-year study of osseointegrated implants in the treatment of the edentulous jaw. Int J Oral Surg 1981;6:387-416. 2. Adell R, Eriksson B, Lekholm U, Brånemark PI, Jemt T. Long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws. Int J Oral Maxillofac Implants 1990;5:347-59.
The Journal of Prosthetic Dentistry
Corresponding author: Dr Ali Bolouri Texas A&M University Baylor College of Dentistry Department of Restorative Sciences, Rm 236 3302 Gaston Ave Dallas, TX 75246 E-mail: [email protected] Copyright ª 2014 by the Editorial Council for The Journal of Prosthetic Dentistry.
Ali and Bhavani
13 to 14 mm between the crest of the edentulous ridge and the occlusal plane, whereas overdentures retained by Locator attachments (Locator; Zest Anchors) require a minimum of 8.5 mm.8,9 Other factors in determining prosthetic success are implant location and angulation,10 both dependent on tooth position. Therefore, determining tooth position is a critical part of the diagnostic process. One of the best tools available to the clinician to aid in pretreatment assessment is the patient’s existing denture, which helps the dentist identify the patient’s preferences and assess expectations.11 If the patient presents with a well-fitting and esthetically pleasing existing complete denture prosthesis, it can often be duplicated and used as a radiographic and surgical guide for implant placement. However, if the existing prosthesis is unacceptable, a new interim prosthesis or diagnostic wax-up must be fabricated that can be evaluated in the patient’s mouth to assess esthetics and phonetics before surgery. Implant surgery that is performed without restorative diagnosis usually results in a prosthetic outcome that is less than optimal and, very often, an unsatisfied patient.12 This clinical report describes the management of an
Professor and Director, Removable Prosthodontics Department of Restorative Sciences. Assistant Professor, Department of Restorative Sciences.
b
Ali and Bhavani
unhappy patient who presented after the insertion of a definitive fixed prosthesis and emphasizes the importance of communication and planning before treatment.
CLINICAL REPORT A 68-year-old healthy white male presented for dental treatment. His chief complaint was, “I don’t like the way my front teeth look.” The patient’s dental history revealed that he had had his maxillary arch restored a few weeks previously at another dental office. Since the insertion of his maxillary prosthesis, the patient had noticed changes in his speech, especially during the production of sibilant sounds. His main concern, however, was the discolored right and left maxillary lateral incisors, where composite resin had been used to seal the implant screw access openings on the facial surface (Fig. 1). When questioned about his mandibular prosthesis, the patient stated that the original treatment plan included the fabrication of a mandibular prosthesis, but he did not know whether or when the mandibular arch was going to be restored. Before his current prosthesis, the patient reported wearing conventional maxillary and mandibular complete dentures.
2
Volume
1 Preoperative smile. Note discolored composite resin covering screw access openings in regions of maxillary right and left lateral incisors and incisal edge positioning of maxillary teeth.
The patient’s medical history did not present any contraindications to dental treatment. Intraoral examination revealed a maxillary implant fixed complete denture (FCD) opposing an edentulous mandibular arch with 5 healing abutments (Nobel Biocare). Minimal space was noted between the maxillary occlusal plane and the mandibular ridge, indicating the lack of restorative space for a mandibular prosthesis. A panoramic radiograph showed 6 implants and a metal substructure with long screw access channels in the maxillary arch. The channels appeared to have been sealed with cotton pellets and composite resin. The composite resin was found to extend the entire length of the channels (Fig. 2). Given the lack of restorative space for a mandibular prosthesis due to encroachment of the interocclusal space by the current maxillary prosthesis and the patient’s dislike of the esthetics, a decision was made to remove the maxillary prosthesis. This was accomplished over 2 appointments. The 4 posterior screw access channels were accessed first, then the 2 anterior channels. The prosthesis was removed and healing abutments were placed. At this time, the unfavorable facial angulation of the anterior maxillary implants was clearly visible. Interim maxillary and mandibular complete
Issue
-
2 Pretreatment panoramic radiograph. Note composite resin in screw access channels and minimal space present between occlusal openings of channels and mandibular healing abutments.
overdentures were fabricated and inserted. The placement of healing abutments on the implants allowed for additional support of the complete denture prosthesis and the use of a soft liner (Luci-Sof; Dentsply Intl) in areas of the dentures contacting the healing abutments that provided some frictional retention. The patient was satisfied with the esthetics and the ability to function with the new interim prostheses. The interim prostheses served to motivate the patient, were used to determine restorative space in both arches, and allowed the clinician adequate time to complete the definitive prostheses. After the available treatment options and their advantages and disadvantages were discussed with the patient, a decision was made to fabricate definitive implant-retained maxillary and mandibular overdentures. The main rationales for the treatment choice were the undesirable angulations of the anterior maxillary implants, the amount of restorative space available, and patient preference. The patient was comfortable with the idea of a removable prosthesis and extremely satisfied with his interim dentures. He did not want to add to the cost of treatment significantly and, given the recent problems with his FCD, did not want another fixed prosthesis.
The Journal of Prosthetic Dentistry
-
To assess the maxillary metal substructure, removing the denture base acrylic resin and denture teeth was essential. This was accomplished by soaking the maxillary prosthesis in acetone (W.M. Barr & Co Inc) overnight (Fig. 3). The fit of the computer-aided design/computer-aided manufacturing (CAD/CAM) titanium bar was then assessed and was found to fit intimately and passively on the maxillary implants. To compensate for the labial inclination of the anterior maxillary implants and save the patient the cost of fabricating another bar, a decision was made to salvage the bar. The existing milled bar was modified. The amount of reduction was verified with the help of a putty index (President; Coltène/ Whaledent) of the patient’s new interim complete denture (Fig. 4). Maxillary and mandibular implant level impressions were made with polyvinyl siloxane impression material (Aquasil; Dentsply), and definitive casts were generated. Jaw relation records were completed, and maxillary and mandibular trial dentures were fabricated. The amount of space around the modified bar was again verified with a putty index of the wax trial dentures. Because the space was adequate for a bar overdenture in the maxilla, 4 female low-profile titanium laser bar attachments (Locator) were welded on the bar, 2 in the anterior and 2 in the
Ali and Bhavani
-
2014
3
3 Maxillary computer-aided design/computer-aided manufacturing metal substructure with acrylic resin dissolved with acetone. Note buccolingual width of bar before modification.
4 Silicone putty index to verify reduction. Note adequate space available facially and occlusally. Note change in bar dimension and presence of low profile Locator attachments.
5 A, B, Evaluation of modified bar. Note anteroposterior spread of attachments.
6 Postoperative smile. posterior aspect to maximize the anteroposterior spread (Fig. 5). Because the bar was also made of titanium, the attachments could be welded without
Ali and Bhavani
concerns regarding metal compatibility. The positioning of the female Locator components on the bar was accomplished with the help of a Locator
paralleling mandrel (Zest Anchors) and a dental surveyor. The female components were spot-welded onto the bar. The male processing assembly was then attached to the female component, and welding around the base of the female components was completed to ensure that the additional weld did not interfere with the seating of the male component on the female component. The welded areas were then smoothed and polished. The definitive wax-up was completed, and the overdentures were processed and inserted. The patient was seen for postinsertion appointments at 24 hours and 1 week after insertion. The patient was satisfied with both his maxillary and mandibular prostheses (Fig. 6).
4
Volume DISCUSSION This article describes the management of a patient after definitive therapy. The transition from a fixed implant-supported prosthesis to a removable implant- and tissue-supported prosthesis is not commonly seen in practice. The rationale for the choice of treatment in this situation was the need to compensate for the lack of restorative planning before implant surgery. In some patients, even after careful planning, implant positions and angulations are not ideal. The clinician must reevaluate and sometimes alter the direction of treatment after the implants are uncovered. In this patient, with his poorly angulated maxillary anterior implants, the dentist could have retained the prosthesis with only the 4 distal implants or used a material other than composite resin to seal the screw access hole to allow for easier retrievability. Although the number of implants in the maxilla and mandible in this patient were optimal for a fixed prosthesis, the lack of restorative space made this hard to achieve. To facilitate esthetically pleasing and functional restorations in both arches, a careful analysis of the amount of space available was required. Determining the location of the occlusal plane and maxillary incisal edge position was essential in ensuring that sufficient space was available for a
mandibular prosthesis. This was accomplished by analyzing the esthetics, phonetics, and occlusal vertical dimension. Once definitive tooth positions and the presence of adequate space for a bar overdenture in the maxilla had been determined with the help of the interim prosthesis, the existing CAD/CAM metal substructure was modified by the careful recontouring and welding of 4 attachments. The weldable titanium attachments were compatible with the titanium milled bar. This kept the cost of treatment to a minimum.
CONCLUSION Implant restorations in edentulous patients require careful planning and communication between the patient, restoring dentist, and surgeon. The definitive goal and the steps needed to achieve the best possible outcome should be visualized before treatment is even begun to ensure optimal esthetics and function.
-
Issue
-
3. Handelsman M. Surgical guidelines for dental implant placement. Br Dent J 2006;201:139-52. 4. Stanford CM. Application of oral implants to the general dental practice. J Am Dent Assoc 2005;136:1092-100. 5. Zitzmann NU, Marinello CP. Treatment planning for restoring the edentulous maxilla with implant-supported restorations: removable overdenture versus fixed partial denture design. J Prosthet Dent 1999;82:188-96. 6. Lewis S, Sharma A, Nishimura R. Treatment of edentulous maxillae with osseointegrated implants. J Prosthet Dent 1992;68:503-8. 7. Heydecke G, Boudrias P. Within-subject comparisons of maxillary fixed and removable implant prostheses: patient satisfaction and choice of prosthesis. Clin Oral Implants Res 2003;14:125-30. 8. Sadowsky SJ. Treatment considerations for maxillary implant overdentures: a systematic review. J Prosthet Dent 2007;97:340-8. 9. Lee CK, Agar JR. Surgical and prosthetic planning for a two-implant-retained mandibular overdenture: a clinical report. J Prosthet Dent 2006;95:102-5. 10. Bidra AS, Agar JR. Management of misangulated implants for a maxillary overdenture with spherical abutments: a clinical report. J Prosthet Dent 2011;106:209-13. 11. Jivraj S, Chee W, Corrado P. Treatment planning of the edentulous maxilla. Br Dent J 2006;201:261-79; quiz 304. 12. Binon PP. Treatment planning complications and surgical miscues. J Oral Maxillofac Surg 2007;65(suppl 1):73-92.
REFERENCES 1. Adell R, Lekholm U, Rockler B, Brånemark PI. A 15-year study of osseointegrated implants in the treatment of the edentulous jaw. Int J Oral Surg 1981;6:387-416. 2. Adell R, Eriksson B, Lekholm U, Brånemark PI, Jemt T. Long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws. Int J Oral Maxillofac Implants 1990;5:347-59.
The Journal of Prosthetic Dentistry
Corresponding author: Dr Ali Bolouri Texas A&M University Baylor College of Dentistry Department of Restorative Sciences, Rm 236 3302 Gaston Ave Dallas, TX 75246 E-mail: [email protected] Copyright ª 2014 by the Editorial Council for The Journal of Prosthetic Dentistry.
Ali and Bhavani
