Patients' Expectation Before and Satisfaction After Full-Arch Fixed Implant-Prosthesis Rehabilitation

The indication for implant treatment as the first treatment option in the planning of oral rehabilitation is increasing, as well as becoming more affordable to the general population.¹ 

Particularly for the edentulous mandible, osseointegration could help to solve patients' problems relating to lower complete dentures in severely resorbed mandibles. Due to a reduced basal area caused by residual ridge resorption, these dentures generally present low stability and retention.^2,3 

To overcome this deficiency, one form of treatment is implant-supported, full-arch fixed prosthesis therapy, which has a high success rate and loss of the implant is rare.⁴  An earlier study⁵  evaluated the longevity of dental implants and concluded that it is possible to achieve a high survival after 10 years of use (88–98% and 81–82% for the mandible and maxilla, respectively). Therefore, this rehabilitation method could increase patients' quality of life and improve nutrition when compared to conventional dentures.⁶ 

The goal of implant-supported, full-arch fixed prosthesis therapy is to restore esthetics and function of the stomatognathic system—as well as preserve the integrity of intraoral tissues—in an attempt to satisfy the patient both objectively and subjectively.⁷  Most of the consulted studies report the opinion of patients using questionnaires^8–11  concerning satisfaction and oral function. Due to their high level of satisfaction, the majority of patients reported that they would undergo the same therapy again and would indicate it for others.^8,12,13 

However, several factors may influence patient satisfaction with the prostheses, such as age,¹⁴  bone quality,¹⁵  neurosis,¹⁶  patient-professional relationship,¹⁷  pretreatment expectations,^18,19  and psychological profile of the patient.²⁰ 

The patient-professional relationship and pretreatment expectations are important factors in achieving patients' satisfaction, as they can be optimized by the dentists by improving dentist-to-patient communication or by overcoming psychological or social problems that may interfere with treatment success.¹⁷  Patients often have a certain amount of expectation concerning a dentist's professional skills, as well as concerns about the treatment itself. The task of the dentist is to understand this expectation and evaluate whether it is realistic, considering that patients and dentists evaluate prosthesis in different ways.^21,22 

Thus, this study aims to investigate the expectation before and satisfaction after implant-supported, full-arch fixed prosthesis therapy, as well as the influence of some clinical and patient-related variables concerning these evaluations. Considering previous studies,^11,18,23  the following null hypothesis was set: there are no differences among expectations before and satisfaction after implant-supported complete denture therapy. Secondary aspects—age, gender, clinical variables, and patients' evaluation of dentists—were also checked for possible associations with expectation and satisfaction scores.

The sample was comprised of 28 patients who were rehabilitated with osseointegrated implants at the Dental Clinics of the University of Vale do Paraíba (n = 28). These patients received implant-supported, full-arch fixed prosthesis therapy made by a standard technique. Among the 28 evaluated patients, 11 were men (39.3%) and 17 were women (60.7%). The average age was 58 years (SD 9.2), with 76 and 44 years being the eldest and youngest, respectively. Concerning educational level, 14 (50%) individuals had completed elementary school, 9 (32.1%) high school, 3 (10.7%) higher education, and only 1 (3.6%) was a postgraduate.

With respect to the arch for which the prosthesis was made, most patients received the prosthesis on the lower arch (78.6%). A smaller percentage of patients (14.3%) received the prosthesis in the maxillary arch, and 7.1% received both arches.

The study was approved by the Committee for Ethics in Research of the University of Vale do Paraiba (protocol number H098/CEP/2009).

For the assessment of expectation before and satisfaction after therapy, a visual analog scale (VAS) was used ranging from 0 to 10, where 0 represented the lowest rating (worst possible outcome) and 10 the highest rating (best possible outcome). The patients were asked to attribute VAS scores to evaluations for their expectations before commencement of treatment. After treatment, the scores chosen by the patients corresponded to degree of satisfaction with the outcomes of therapy.

All interviews were carried out by the same researcher who did not have any professional contact with the patients. The initial interviews were undertaken after the dentists' explanation to the patients about the advantages and disadvantages of the proposed treatment, and after the patients' acceptance of the proposed treatment (but before commencement); the final interviews were carried out after the last postdelivery adjustment.

In both situations, before and after treatment, the patients assigned scores to four aspects: esthetics of the prosthesis, chewing, comfort of wear, and phonetics.

Specific questions patients were asked prior to the treatment were:

1. On a scale of 0–10, how would you score the esthetic benefits you expect from the treatment?

2. On a scale of 0–10, how would you score the benefits regarding chewing you expect from the treatment?

3. On a scale of 0–10, how would you score the benefits you expect concerning comfort after the prosthesis?

4. On a scale of 0–10, how would you score the benefits you expect concerning phonetics?

Specific questions patients were asked after treatment were:

1. On a scale of 0–10, how would you score the esthetic benefits you observed following treatment?

2. On a scale of 0–10, how would you score the benefits concerning chewing you observed following treatment?

3. On a scale of 0–10, how would you score the benefits concerning comfort with the prosthesis following treatment?

4. On a scale of 0–10, how would you score the benefits concerning phonetics following treatment?

Clinical variables and patient-related variables including gender, age, educational level, the arches on which the prosthesis were made, number of implants, loss of implants during therapy, radiographically and surgically assessed bone quality, number of postdelivery adjustments and angulations of the implants. All scores were documented.

A questionnaire was also used concerning patients' evaluation of the dentists' conduct, using a Likert scale from 1–5, based on previously developed questionnaires.^24,25  This questionnaire had 10 questions, in which the first 7 had responses such as: strongly disagree (a score of 1), disagree (scored as 2), not sure (scored as 3), agree (scored as 4), or strongly agree (scored as 5).

Data was tabulated and descriptive statistics were formulated. Chi-square and Wilcoxon tests were used to compare the differences between average VAS scores for expectations before and satisfaction after treatment for all evaluated aspects (chewing, esthetics, comfort, and phonetics).

The Mann-Whitney test was used to assess if there were significant differences for average VAS scores when comparing qualitative variables with gender and question 9: “The dentists I saw answered my questions” (in the questionnaire concerning patients' evaluation of dentists' conduct). The Kruskal-Wallis test was used to assess whether there were significant differences concerning average VAS scores when comparing qualitative variables with 3 or more answers (educational level, the arch[es], and clinical variables) in which the prosthesis were made, radiographically and surgically assessed bone quality, angulations of the implants with question 10: “Which word(s) better describe the dentists you saw?” on the questionnaire concerning patients' evaluation of the dentists' conduct).

The Spearman correlation test was used to determine whether there was a correlation between expectation before and satisfaction after treatment, as well as between patients' age, number of implants, number of adjustments after delivery, scores of questions 1–7 of the questionnaire concerning patients' evaluation of the dentists' conduct and VAS scores for the four evaluated aspects. All tests adopted a significance level of 5%.

Regarding radiographic bone quality, it was considered to be “satisfactory” in 10 (35.7%) patients, “good” in 8 (28.6%),“excellent” in 5 (17.9%), and “poor” in 5 (17.9%). For surgical bone quality, it was observed that 9 (32.1%) were evaluated as “satisfactory,” 8 (28.6%) as “good,” 7 (25.0%) as “poor,” and 4 (14.3%), as “excellent.” The inclination of the implants was “acceptable” in 17 (60.7%) patients, “adequate” in 8 (28.6%), and “bad” in only 3 (10.7%).

The average number of adjustments was 1.3 (SD 0.8), 3 being the greatest and 0 the least number of adjustments. The final number of installed implants per patient had a mean of 6.1 with a standard deviation of 2.0 (13 the maximum and 4 the minimum number of implants).

Table 1 shows the average scores for pretreatment expectation and posttreatment satisfaction for chewing, esthetics, comfort, and phonetics. It was observed that the scores were high and that there were no statistically significant differences among the scores (Wilcoxon test) for all items.

Tables 2 and 3 present the results of the questionnaire regarding patients' evaluation of the dentists' conduct. In questions 8 and 9 of that questionnaire, patients could answer “definitely yes,” “yes,” “probably,” “maybe,” or “never.” For question 8 (“The dentists I saw were impersonal or indifferent”) ”never” was the response by 26 patients (92.9%), where one patient (3.6%) answered “definitely yes” and another patient (3.6%) answered “maybe.” In question 9 (“The dentists I saw answered my questions”), 19 patients (67.9%) answered “definitely yes” and 9 (32.1%) answered “yes.” For question 10 (“Which word(s) better describes the dentists you saw?”), 20 patients (71.4%) described the dentist as “professional and careful,” 5 (17.9%) as “professional,” and 3 (10.7%) as “careful.”

A significant difference was observed on average expectation VAS scores between genders regarding esthetics (P = 0.040), phonetics (P = 0.043), and comfort (P = 0.013), as seen in Table 4. Likewise, a positive correlation was found between expectations before and satisfaction after treatment only for esthetics (56.1%, P = 0.002).

However, there was no association for age or educational level and VAS scores for all evaluated aspects. There was also no association among clinical variables—the arch(es) in which the prosthesis were made, number of implants, bone quality assessed radiographically and surgically, number of postdelivery adjustments, and angulations of the implants—and average VAS scores for all evaluated criteria.

The questionnaire regarding patients' evaluation of the dentists' conduct showed no association with gender or with educational level. Further, there was no correlation between the questionnaire and VAS scores for all evaluated aspects.

The null hypothesis of this study—that there are no differences among expectation before and satisfaction after full-arch fixed implant-prosthesis rehabilitation—was verified. Patients in this sample presented high but similar VAS scores for expectation before and satisfaction after treatment for all evaluated aspects (chewing, esthetics, phonetics, and comfort). Previous papers^11,13,18  that were the rationale for our hypothesis also presented high expectation and satisfaction scores; however, the satisfaction scores exceeded the expectation. The present study did not find such a difference, comparable to the results obtained by Siqueira et al.²⁶ 

It was also observed that there was no correlation between expectation before and satisfaction after treatment for the categories of chewing, phonetics, and comfort; however, there was a positive correlation for esthetics. This correlation may indicate that patients' expectation for esthetics influences their satisfaction with the same item, and that this aspect should be assessed by the dental professionals in an attempt to predict how patients will evaluate their implants treatment. These results corroborate findings of former studies in patients with implant-supported prostheses.^18,19 

An association was found between female gender and expectation for esthetics, phonetics, and comfort, with women giving higher scores than did men; this is different from that observed in former studies,^18,26  which did not find such an association. Also, there was no association among the arches in which the prosthesis were made, number of implants, bone quality assessed radiographically and surgically, number of postdelivery adjustments and angulations of the implants with pretreatment expectations or posttreatment satisfaction with the final outcome of the therapy for all evaluated criteria. To the best of our knowledge, there is no published data regarding patient expectation before and satisfaction after implant prosthesis to evaluate the influence of the aforementioned clinical variables.

Considering that the patient-professional relationship can exert an influence on patient satisfaction with the prosthesis,^{15,17,22,23,26}  as well as the success of the therapy, we assessed the association between the assessment of the dentist's conduct by the patient and patient pretreatment expectation and posttreatment satisfaction. Using the questionnaire regarding patients' evaluation of the dentists' conduct, it was possible to verify that patients' impressions regarding the dentists were very positive. However, no association was found with VAS scores for pretreatment expectations and posttreatment satisfaction for all evaluated items. These findings are dissimilar to those previously reported.²³ 

A limitation of the present study is its correlational design, which does not allow determination of a causal relationship among the studied variables. The use of VAS scores, although suitable for measuring subjective clinical phenomena, has also some limitations, mainly regarding its content validity.²⁷  Furthermore, other variables not approached here may play a role in the patients' expectation before and satisfaction after implant-supported, full-arch fixed prosthesis therapy. A qualitative approach might reveal more about the expectation and satisfaction of these patients and what they actually think about dentists. Another limitation concerns the sample size. It is well known that larger samples should bring about more reliable results. Therefore, further studies using qualitative methodologies and larger samples could be undertaken in the future to assess the influence of the patient-professional relationship more thoroughly concerning expectation and satisfaction with implant therapy.

Considering the limitations of this study, it is possible to conclude that VAS scores for expectation before treatment were similar to those obtained after treatment and that women presented higher expectations.

Abbreviation

VAS

visual analog scale

The authors would like to thank the institution of FAPESP (2010/05298-0) for providing funding for the first author. The article was revised by a native English speaker and professional translator-proofreader, Vivienne Roberts Hegenberg. The article was also revised by a statistical consultant, J. Adams.