Low-Cost Implant Overdenture Option for Patients Treated in a Predoctoral Dental School Curriculum

Milieu in Dental School and Practice Low-Cost Implant Overdenture Option for Patients Treated in a Predoctoral Dental School Curriculum Michael S. McCracken, D.D.S., Ph.D.; Ruth Aponte-Wesson, D.D.S., M.S.; S. Jean O Neal, D.M.D., M.S.; Kavita Rajdev, B.D.S. Abstract: In an effort to make the implant overdenture more affordable for patients, a pricing package at the University of Alabama at Birmingham School of Dentistry was established. This package includes two implants, two dentures (upper and lower), and two implant abutments, all for $975. It is known as the 2-2-2 implant program. One concern regarding the program was whether patients would complete overdenture treatment or simply receive implants at this relatively low cost and have the implants restored outside the school. The purpose of this retrospective chart review was to determine how many patients in 2004 received implants as part of this program and how many of these patients completed overdenture treatment. Other data (age, distance from school, number of teeth at start of treatment, and gender) were collected to identify variables that might be associated with greater likelihood of completing overdenture treatment. In 2004, fifty-one patients received 102 implants as part of this program. Two patients had a failed implant prior to restoration (two of 102 implants), and one patient was referred to graduate prosthodontics for restoration. Of the remaining forty-eight patients, forty-one completed overdenture treatment (85 percent), and seven (15 percent) were lost to follow-up. The mean age of patients receiving this treatment was 60.7 years. The mean distance traveled to the school was 70.7 miles. While no variables showed significant predictive value, point estimates (estimate of the odds ratio) suggest that older patients and patients who travel greater distance to the school were less likely to complete treatment. The low-cost implant overdenture has been an important addition to our curriculum. The majority of patients who receive implants as part of this program complete overdenture treatment. Dr. McCracken is Associate Professor and Director of Predoctoral Implant Education, Department of Prosthodontics; Dr. Aponte- Wesson is Assistant Professor and Clinical Director of Predoctoral Implant Education, Department of Prosthodontics; Dr. O Neal is Professor and Chair, Department of Prosthodontics; and Dr. Rajdev is a graduate assistant in the Department of Prosthodontics all at the University of Alabama at Birmingham School of Dentistry. Direct correspondence and requests for reprints to Dr. Michael S. McCracken, University of Alabama at Birmingham School of Dentistry, Room 606, 1919 Seventh Ave. South, Birmingham, AL 35243; 205-934-1593 phone; 205-975-6108 fax; mikemc@uab.edu. Key words: dental implant education, overdenture, treatment outcome Submitted for publication 12/12/05; accepted 2/6/06 Many dental schools now offer dental implant education to predoctoral students, 1-3 and this education appears to impact practice habits after dental school. 4 However, the cost of dental implants can still be a barrier for patients, even at dental school fees. In an effort to make dental implants more affordable for our edentulous patients, we implemented a price package for a mandibular implant overdenture, which we call the 2-2-2. For $975, patients can receive two implants, two dentures (one upper and one lower), and two abutments (Table 1). Other services that may be required, such as extractions, sedation, or interim dentures, are charged at normal school prices. The 2-2-2 program has greatly increased the volume of implant patients available for predoctoral students to restore, pushed demand for surgical placement of implants at the graduate level, and stimulated interest in dental implants among staff, students, and faculty. At such low fees, however, some concern was expressed among the faculty that patients who have implants placed may not follow through with overdenture treatment. The purpose of this retrospective chart review, therefore, was to determine how many patients who received implants under the 2-2-2 program in 2004 completed their treatment with a mandibular overdenture. Also, demographics characterizing these patients are reported. 662 Journal of Dental Education Volume 70, Number 6

Materials and Methods After obtaining appropriate Institutional Review Board approval for the project, we identified patients receiving implants in 2004 under the 2-2-2 program through computer records of clinical procedures. These charts were retrieved and reviewed to determine whether patients had completed overdenture treatment by the end of 2005. Four treatment outcomes were considered: completed treatment, not restored, referred to another clinic, or failed implant. The calendar year 2004 was selected for implant placement because it was the most recent year of record that would still allow patients reasonable time for overdenture restoration. All patients received two mandibular implants under a standard school protocol. Briefly, the protocol includes the following. Patients are identified in the normal predoctoral treatment planning process. Patients are evaluated by a prosthodontist with the student. If the patient does not have a diagnostic set of current dentures, a diagnostic waxing may be requested by the faculty. Patients are evaluated by a surgical resident (oral surgery or periodontology). Implants are placed in the B and D positions in the edentulous mandible, which may be defined as 7 mm distal to the midline on each side. Implants are placed in a two-stage approach. Provisional dentures (if present) are relined at the time of surgery with a soft liner. Implants are uncovered after three months, and healing abutments are placed. After three weeks, the patient returns to the predoctoral clinic for restoration and overdenture fabrication. Demographic data on this population was collected and analyzed descriptively. Distance from the school was computed by zip code using Mapquest (www.mapquest.com). For patients of record who choose this treatment option, start of treatment was defined as the date of the overdenture treatment plan. Data were also analyzed using multivariable logistic regression to determine if treatment outcome could Table 1. Services offered under the 2-2-2 implant overdenture pricing package Service Price Charged Cost 2 Mandibular implants $300 each $600 2 Abutments $25 each $50 Mandibular overdenture $300 $300 Maxillary denture (if needed) $25 $25 TOTAL $975 Note: Total price for this package is $975. Other required treatment (extractions, sedation, provisional dentures, etc.) is charged at usual school prices. be predicted by demographic variables. Only patients who completed treatment or were not restored were considered in this analysis (patients who had a failed implant or were referred to another clinic were not included). For statistical analysis, statistical software was utilized with alpha set at 0.05 unless otherwise noted (SAS v.9.1; SAS Institute, Cary, NC). Results In 2004, fifty-one patients received implants as part of the 2-2-2 program, representing 102 implants. Of these patients, forty-one completed treatment, seven were not restored, two patients had a failed implant, and one patient was referred to the graduate prosthodontic program for restoration. All patients treated in 2004 received an upper denture. Median and mean age (with 90 percent CI) and distance to school variables are summarized in Table 2, along with number of teeth present at the start of treatment. Mean distance traveled to the school for treatment was 70.7 miles. Of the fifty-one patients who received implants, twelve drove over 100 miles to be at the school; one patient drove over 300 miles. Four patients were from states other than Alabama. The median age at the start of treatment was sixty-two Table 2. Mean and median demographic characteristics of patients receiving the 2-2-2 mandibular overdenture treatment plan Characteristic Median Mean (90% CI) Range Age 62 60.7 (57.7 63.7) 31 85 Distance to School (miles) 64 70.7 (57.8 83.7) 2 312 Max Teeth (start of treatment) 0 2.7 (1.8 3.7) 0 13 Mand Teeth (start of treatment) 3 4.1 (2.9 5.1) 0 15 June 2006 Journal of Dental Education 663

years. Twenty-five percent of these patients were over the age of seventy; 25 percent were age fifty or less. Patients tended to have more lower teeth than upper teeth at the start of treatment. Thirty-two of fifty-one patients (63 percent) were edentulous in the maxilla, and approximately half (51 percent) were edentulous in the mandible. The odds ratios to complete treatment associated with demographic variables are listed in Table 3. While the model did converge, confidence intervals for this data were large, and no prediction factors were correlated with completing overdenture treatment at a statistically significantly level. Discussion The overall completion rate of forty-one of fifty-one patients (80 percent) was in line with expectations. While the loss of seven patients (14 percent) to follow-up is not desirable, it appears to be comparable to the number of patients who discontinue treatment for traditional complete dentures. Table 3. Patients receiving implants for the 2-2-2 mandibular overdenture package and association with failure to complete treatment Characteristic Number (N=51) Adjusted OR (95% CI) Age (years) Less than 55 19 1.0 55 to 64 13 1.6 (0.1, 27.9) 65 and over 19 5.8 (0.6, 54.0) Gender Male 22 1.0 Female 29 0.6 (0.1, 3.9) Distance from School 0-29 miles 13 1.0 30-74 miles 17 4.8 (0.2, 101) 75+ miles 21 7.6 (0.5, 112) Edentulous Maxilla (at start of treatment) No 19 1.0 Yes 32 0.1 (0.01, 3.9) Edentulous Mandible (at start of treatment) No 25 1.0 Yes 26 2.4 (0.3, 24.3) Treatment Outcome Completed 41 Lost to follow-up 7 Failed implant 2 Referred to grad program 1 Matched control patients receiving complete dentures were not evaluated for this study. Two implants of 102 placed failed in this sample. Both of these patients had the implant removed and subsequently replaced. Since this added to the necessary treatment time, these patients were not considered in this study. While no implant failure is acceptable, these data are consistent with other studies of implant success and meet our expectations of surgical success at the residency level of training. 5,6 Patients traveled a long distance to receive oral health care at the dental school. Adding the travel time to the appointment time, a visit to the dental school becomes a day-long event for a large percentage of our patients. Certainly this could be considered a barrier to care. 7 These data reinforce the need to treat patients as efficiently as possible and to be conscious not only of their financial costs, but of their time and travel costs as well. Factors analyzed for association with completing overdenture treatment were not statistically significant. However, trends in the data may be of interest. Point estimates suggest that older patients are less likely to complete treatment. This could be a result of less access to care due to less mobility, increased medical concerns, or financial fixed income considerations that may increase in the elderly population. 8,9 Patients who traveled farther were less likely to complete therapy, according to point estimates. This would seem intuitive, as patients who have greater time and travel costs to get to the school would have less incentive to complete therapy. The mean tooth loss demonstrated in this group is greater than expected. Even considering only patients over the age of sixty, these patients have on average nineteen teeth. 10 Obviously, people with more teeth would be less likely to seek overdenture treatment. The pattern of tooth loss in this sample is typical, with more teeth present in the mandible than in the maxilla; the last remaining teeth are usually located in the anterior mandible. 11 According to point estimates, patients who were edentulous in the maxilla at the start of treatment were much more likely to complete overdenture therapy, while patients edentulous in the mandible were 2.4 times less likely to complete treatment. No explanation for this dichotomy is readily apparent, other than idiosyncratic occurrence, which may be partly due to the sample size investigated. Literature shows that the two-implant overdenture can enhance quality of life and systemic 664 Journal of Dental Education Volume 70, Number 6

health. 12-14 In an effort to make implant therapy for the edentulous patients more affordable, we lowered prices for minimal implant treatment (a two-implant overdenture) to under $1000. To create communication and treatment planning efficiencies, we bundled this treatment as a package. We feel that packaging in this way has helped internal communication and word-of-mouth marketing among patients. Patients now walk in the door of the school asking for the 2-2-2 implant overdenture. Staff, faculty, and business personnel are all now familiar with the overdenture treatment and the protocol associated with it. Protocols for surgery and implant inventories are streamlined as well. We are able to price this treatment at this point due in large part to generous educational support from corporate sponsors, so that most of our patients can afford this implant treatment. Our corporate sponsors include, in alphabetical order, 3i (3i Implant Innovations, Inc., Palm Beach Gardens, Florida), BioHorizons (BioHorizons Implant Systems, Inc., Birmingham, Alabama), Nobel Biocare (Nobel Biocare AB, Goteborg, Sweden), and Zimmer Dental (Zimmer Dental, Inc., Carlsbad, California). We utilized a cost differential between the upper and lower denture in the pricing plan ($25 vs. $300; see Table 1). This was in an effort to keep revenues close to the established level of $975. Some patients do not need a maxillary denture, either because they are dentate in the maxilla or their denture is sufficient. In this situation, their treatment cost is slightly less, $950. The cost for this treatment at usual school prices restored by a senior would be $2180, as follows: two implants at $750 each (resident fees), two abutments at $125, and upper and lower dentures at $215 each. By using the 2-2-2 package, patients save $1205. A typical fee for this service in private practice in our community would be around $5300. Our hope in starting this program was that three objectives would be realized. First, we wanted to increase access to care for edentulous patients who could not otherwise afford implants. Second, we Implants Restored by Seniors 300 250 Implants Restored (N) 200 150 100 50 0 2000 2001 2002 2003 2004 2005 Year of Graduation Figure 1. Number of implants restored by each graduating senior class Note: Restoration of implants by predoctoral students at UAB began in 1999 with a pilot program of eight students. Each year the number of implants restored has increased. In the most recent year, seniors restored 244 implants, or 4.4 implants per student (class size of 55). All students are expected to restore an implant prior to graduation. June 2006 Journal of Dental Education 665

wanted to increase the numbers of implants available to seniors to restore, as well as the number of implants placed by the residents. Finally, we hoped the program would increase revenues to the school by moving patients from complete denture therapy to the implant overdenture treatment. We feel that all three of these goals were achieved. This overdenture program is part of our overall goal of increasing utilization of implant dentistry among our predoctoral students. We began restoring implants with seniors as a pilot program (eight students) in 1999. The program has expanded each year (Figure 1). At this point, after six years, each student is expected to restore at least one implant prior to graduation. In our most recent year, seniors restored 244 implants, or 4.4 implants per student. The majority of implants restored are fixed units; 2-2-2 overdenture implants typically represent 2/5 of implants restored in any given year. Limitations of this study include the lack of a comparison group (for example, complete denture wearers), large confidence intervals associated with the point estimates, and the modest sampling size in this observational study of fifty-one patients. Conclusions The low-cost overdenture option in this university setting generated demand for more than 100 dental implants, making this an important part of our educational program at UAB. It is likely that patients receiving dental implants as part of this program will complete therapy. Of 102 implants placed in 2004 as part of this program, only two failed before restoration. Increasing age and greater distance from the school may be associated with a tendency to not complete overdenture therapy. REFERENCES 1. Lim MV, Afsharzand Z, Rashedi B, Petropoulos VC. Predoctoral implant education in U.S. dental schools. J Prosthod 2005;14:46-56. 2. Afsharzand Z, Lim MV, Rashedi B, Petropoulos VC. Predoctoral implant dentistry curriculum survey: European dental schools. Eur J Dent Educ 2005;9:37-45. 3. Klokkevold PR. Implant education in the dental curriculum. J Calif Dent Assoc 2001;29:747-55. 4. Huebner GR. Evaluation of a predoctoral implant curriculum: does such a program influence graduates practice patterns? Int J Oral Maxillofac Implants 2002; 17:543-9. 5. de Baat C. Success of dental implants in elderly people: a literature review. Gerodontology 2000;17:45-8. 6. Jeffcoat MK, McGlumphy EA, Reddy MS, Geurs NC, Proskin HM. A comparison of hydroxyapatite (HA)- coated threaded, HA-coated cylindric, and titanium threaded endosseous dental implants. Int J Oral Maxillofac Implants 2003;18:406-10. 7. Zittel-Palamara K, Fabiano JA, Davis EL, Waldrop DP, Wysocki JA, Goldberg LJ. Improving patient retention and access to oral health care: the CARES program. J Dent Educ 2005;69:912-8. 8. Dolan TA, Atchison K, Huynh TN. Access to dental care among older adults in the United States. J Dent Educ 2005;69:961-74. 9. Kiyak HA, Reichmuth M. Barriers to and enablers of older adults use of dental services. J Dent Educ 2005;69:975-86. 10. Beltran-Aguilar ED, Barker LK, Canto MT, et al. Surveillance for dental caries, dental sealants, tooth retention, edentulism, and enamel fluorosis, United States, 1988-1994 and 1999-2002. MMWR Surveill Summ 2005;54:1-43. 11. Paulander J, Axelsson P, Lindhe J, Wennstrom J. Intraoral pattern of tooth and periodontal bone loss between the age of 50 and 60 years: a longitudinal prospective study. Acta Odontol Scand 2004;62:214-22. 12. Morais JA, Heydecke G, Pawliuk J, Lund JP, Feine JS. The effects of mandibular two-implant overdentures on nutrition in elderly edentulous individuals. J Dent Res 2003;82:53-8. 13. de Oliveira TR, Frigerio ML. Association between nutrition and the prosthetic condition in edentulous elderly. Gerodontology 2004;21:205-8. 14. Raghoebar GM, Meijer HJ, van t Hof M, Stegenga B, Vissink A. A randomized prospective clinical trial on the effectiveness of three treatment modalities for patients with lower denture problems: a 10 year follow-up study on patient satisfaction. Int J Oral Maxillofac Surg 2003; 32:498-503. 666 Journal of Dental Education Volume 70, Number 6