Treatment Outcomes Based on Patients Self-Reported Measures after Receiving New Clasp or Precision Attachment-Retained Removable Partial Dentures

Transcription

1 Treatment Outcomes Based on Patients Self-Reported Measures after Receiving New Clasp or Precision Attachment-Retained Removable Partial Dentures Sanja Peršić, DMD, PhD, 1 Josip Kranjčić, DMD, 1 Daniela Kovačević Pavičić, PhD, 2 Vlatka Lajnert Mikić, PhD, 2 &AsjaČelebić, PhD 3 1 Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Zagreb, Croatia 2 Department of Prosthodontics, School of Medicine, Study of Dental Medicine, University of Rijeka, Rijeka, Croatia 3 Department of Prosthodontics, School of Dental Medicine and Clinical Hospital Centre Zagreb, University of Zagreb, Zagreb, Croatia Keywords Removable partial denture; clasps; precision attachment; treatment outcomes; structured questionnaires (OHIP-14, OES, CFQ). Correspondence Sanja Peršić, Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Gundulićeva, Zagreb, Croatia. persic@sfzg.hr The authors deny any conflict of interest. Accepted July 29, 1 doi:.1111/jopr.1239 Abstract Purpose: To evaluate effects of a treatment taking into consideration esthetics, chewing, and oral health-related quality of life (OHRQoL) of two tooth replacement strategies for maxillary partially edentulous patients with clasp (C-RPD) and precision attachment (PA-RPD) removable partial dentures (RPD). Materials and Methods: The study included 1 patients (72 men, 78 women) who received maxillary ; 88 patients received clasp and 62 patients received precision attachment. Patients completed three questionnaires before treatment and again 3 months after treatment: the Orofacial Esthetic Scale (OES), the Oral Health Impact Profile (OHIP-14), and the Chewing Function Questionnaire (CFQ). Statistical analysis comprised descriptive statistics, paired t-test, and two-factor ANOVA. Results: Both RPD treatments yielded better after-treatment summary scores when compared with the baseline scores (p <.1); however, better results were obtained in the PA-RPD group. Gender, as a single factor, did not yield significant effects; mutual interaction of retention type and gender yielded significant effects. The PA- RPD female group assessed esthetics, chewing function, and OHRQoL significantly better than males, and significantly worse than males in the C-RPD group. The covariate baseline scores yielded statistically significant effects; patients with worse pretreatment condition benefited more from both therapies. Conclusions: Treatment outcomes were better in the PA-RPD group than the C-. Women showed greater concern for the treatment outcomes; their rates were significantly better than in male patients in the PA-RPD group; however, when their satisfaction was lower, their rates were significantly worse than in male patients (in the C-RPD group). Partially edentulous patients without posterior abutment teeth can be treated with implant- fixed partial dentures (I-FPD) or removable partial dentures (RPD) or they can be left with shortened dental arches (SDA). 1-6 Patients without posterior teeth may not be candidates for dental implant therapy due to lack of bone support, financial limitations, or compromised general health conditions. Despite the growing trend to use fixed implant dental prostheses or the SDA concept to maintain satisfactory orofacial function among older age groups, have still been the most common treatment option. 4 However, in contemporary prosthodontic rehabilitation there have been conflicting opinions about RPD manufacture and design. Although some studies found that caused a damage to remaining teeth and supporting tissues, 7-9 others showed satisfactory clinical results with clasp- with a survival rate of 9% after years and a low extraction rate of abutment teeth. 9, A lot of knowledge, contemporary and conventional treatment techniques, and planning have been required in successful restorations of dentition with. 11 In clasp- metal framework, time and cost efficiency have been considered as advantages for both clinicians and patients, whereas reduced esthetics has been considered a disadvantage by precision attachments (PA-) are supposed to be better esthetic alternatives to clasp- (C-). 13,14 However, whether any clinical differences exist between C- and PA- in relation to chewing function and oral health related quality of life (OHRQoL) has not been thoroughly investigated. Metal Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists 1

2 Patient Assessed RPD Therapy Outcome Peršić et al Table 1 A brief overview of questionnaires used in the study with their summary score ranges and questions (items): OES (8 questions), OHIP-14 (14 questions), and CFQ ( questions) Orofacial Esthetic Scale (OES) Oral Health Impact Profile (OHIP-14) Chewing Function Questionnaire (CFQ) How do you feel about the appearance of your (mouth, teeth or tooth replacements)? Have you had (problems or feelings that)..... because of problems with teeth, mouth, dentures? Have you had any difficulty chewing foods such as..... (or similar)? Lower third of your face Pronouncing words Apple, raw carrots Lower third of face (profile) Sense of taste worsened Bacon, firm meat Mouth (smile, lips, visible teeth) Painful aching (mouth, teeth) Biscuits, crackers Teeth rows Uncomfortable to eat any foods Fresh bread, doughnut Shape/form of teeth Been self-conscious Nuts, pecan, almonds, peanuts, macadamia Color of teeth Felt tense Lettuce, raw cabbage Gums Diet been unsatisfactory Biting different foods Overall appearance (mouth, face, teeth) Interrupt meals Chewing gum Scores 1 ; Summary score 8 4 Difficult to relax Have you felt insecure when chewing Feel a bit embarrassed Have you noticed food catching on your teeth or tooth replacement Irritable with people Scores 4; Summary score 4 Difficulty doing usual jobs Life in general less satisfying Totally unable to function Scores 4; Summary score 6 base provide the highest therapeutic improvements of OHRQoL when compared to acrylic or complete dentures (CDs). 1 However, previous studies did not assess differences between C- and PA-. The impact of oral disorders and interventions on individually perceived oral health outcomes have been increasingly recognized as an important health component. Except for the globally used OHIP questionnaire, which measures OHRQoL, 16,17 two new questionnaires have been developed recently. One of them, the Orofacial Esthetic Scale (OES), 18,19 has been used for patient evaluation of orofacial esthetics. Another, the Chewing Function Questionnaire (CFQ), has been used for patient evaluation of a chewing function. The aim of this study was to evaluate the treatment effects considering orofacial esthetics, chewing function, and OHRQoL of two conventional tooth replacement strategies for maxillary partially edentulous patients: clasp and precision attachment, as well as to assess possible gender differences. Materials and methods Patients A cohort of 1 patients of older age (72 men and 78 women, age range from 61 to 84 years) who received maxillary was chosen from patients seeking treatment at the Department of Prosthodontics, School of Dental Medicine, University of Zagreb, between January 13 and October 14. After clinical examinations, panoramic radiographic evaluations, and analyses of mounted diagnostic casts in semi-adjustable articulators, all patients were first offered different therapies: implantsupported FPDs (in patients with sufficient bone support), SDA (for patients with at least teeth in both jaws with at least 4 occluding pairs of premolars, two on each side of jaws), or. Patients were thoroughly informed about all possible therapeutic modalities. Only those patients who chose a conventional treatment with in the maxilla were included in the study. They were further offered two options: tooth-supported FPDs in anterior regions together with in the maxilla by precision attachments or clasp-. Patients who were not willing to undergo the tooth preparation and/or could not afford precision attachment RPD treatment, due to increased cost, received clasp-. All patients included in the study were first-time partial denture wearers in the maxilla; however, all already had Kennedy class Imandibular. were provided in the clinical courses of the dental school. They were strictly supervised by experienced full-time teachers and followed standardized protocol. Patients included in the study had minimum four and maximum six remaining natural teeth in the maxilla with satisfactory prognosis (no deep periodontal pockets, minimal chances for extraction within the next years) and had no medical conditions that could have precluded routine dental treatment. Each patient completed a written consent form prior to the treatment and the Ethics Committee, School of Dental Medicine, University of Zagreb approved the study. A total of 88 patients received clasp-, and 62 received precision attachment (ASC 2 micro; Microtecnor, Buccinasco, Italy). All dentures were CoCr alloy cast frameworks. The precision attachment RPD patients also received metal-ceramic anterior FPDs with extracoronal matrices, which allowed two functional movements of a denture: 2 Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists

3 Peršić et al Patient Assessed RPD Therapy Outcome A B C OES Summary Scores OHIP Summary scores CFQ Summary scores Baseline scores Baseline scores Baseline scores A er treatment scores A er treatment scores A er treatment scores Clasp Precision a achme nt Clasp Precision a achme nt Clasp Precision a achmen t Figure 1 Mean baseline and after treatment summary scores with standard deviations of the following questionnaires: (A) Orofacial Esthetic Scale (OES), (B) Oral Health Impact Profile (OHIP-14), and (C) Chewing function Questionnaire (CFQ) in removable denture wearers by clasps or precision attachments. vertical translation and posterior rotation of denture extension base. The respective FPDs were designed to receive rigid indirect retainers in the form of rests. All clasp- had cast facial arm clasps with rigid reciprocal elements and/or indirect retainers cingulum or occlusal rests. No prosthodontic interventions were made in the mandible, because all included patients were already wearing conventional clasp-, well-fitting. The quality of existing mandibular was assessed by a trained prosthodontist. Patients with natural dentition, implant-supported dentures, or complete removable dentures in the mandible, were excluded to exclude possible impacts of opposing jaw status. Patients younger than 6 years were also excluded to eliminate possible differences in esthetic appreciation among younger patients. 21,22 A prosthodontics specialist, who was not involved in new denture construction, evaluated the quality of the old mandibular and new in the maxilla and rated denture retention and stability using a 1 to 3 scale (1 = poor quality, 2 = sufficient quality, 3 = excellent quality). Three specialists in prosthodontics separately evaluated different prior to the assessment. Kappa test revealed sufficient consistency between them (.7 to.9), but it was decided that only one of the dentists should evaluate all patients; however, only those patients whose were assessed as excellent were allowed to take part in the study. Other patients were excluded (three patients), as insufficient quality of their dentures could negatively affect the results. Questionnaires The OHRQoL was measured using the Croatian version of the OHIP-14 questionnaire. 22 Patients completed the OHIP- 14 questionnaires using a Likert-type scale ranging from to 4. The summary scores ranged from (minimum) to 6 (maximum), the higher score representing more impaired OHRQoL. The Croatian version of the Orofacial Esthetic Scale (OES- CRO) 19 was used to assess patients self-perceived orofacial esthetics. Patients rated their orofacial esthetics on a Likert scale ranging from 1 to (1 = completely unsatisfied; = completely satisfied): the summary scores ranged from 1 to 4. The higher summary scores indicated greater satisfaction with esthetics. 19 The CFQ was used to measure patients self-perceived chewing function. The CFQ consisted of items. Patients rated their chewing ability using a Likert scale ranging from to 4. Higher scores represented more impaired chewing function. The CFQ summary scores ranged from to 4. All three questionnaires were psychometrically tested in previous studies and showed excellent psychometric properties. 19,,23 A brief overview of the questionnaires and their items, scale used, and summary score ranges is presented in Table 1. Patients completed the questionnaires twice, first at the baseline, when they came to a dental clinic for therapy and the second time at least 3 months after they had received their new with all the necessary adjustments made. Statistical analysis was performed with SPSS for Windows. Parametric tests were used, as data (summary scores) were normally distributed (one-way Kolmogorov-Smirnov test). Paired Student t-test was used to test the significant differences between the baseline scores and the after-treatment scores for all three questionnaires for all patients. The twofactor ANOVA was performed with dependent variables: aftertreatment OES, after-treatment OHIP-14, and after-treatment CFQ scores; and two factors: type of RPD retention (clasps vs. precision attachments) and gender (male, female) with the baseline score of each questionnaire as the covariate. Pearson correlation coefficients between the baseline and the aftertreatment summary OES scores were also calculated. p. was considered statistically significant. Results Mean baseline and after-treatment summary scores with standard deviations for all three questionnaires in clasp- Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists 3

4 Patient Assessed RPD Therapy Outcome Peršić et al Table 2 Significant differences of the baseline scores and aftertreatment scores for the Orofacial Esthetic Scale (OES), Oral Health Impact Profile (OHIP-14), and Chewing Function Questionnaire (CFQ) in removable denture wearers () dependent on the type of retention (clasps or precision attachments) Type of prosthodontic treatment Before treatment: after treatment questionnaire score t df p Clasp- OES <.1 OHIP <.1 CFQ <.1 Precision attachment OES <.1 OHIP <.1 CFQ <.1 After treatment OES summary scores 4 3 clasps precision attachments Retention of removable denture Gender Female Male Figure 2 Mean values and standard deviations of the after-treatment OES summary scores in different types of RPD retention dependent on gender. and precision attachment RPD patients are shown in Figure 1. The results of the paired Student t-test between the baseline and the after-treatment summary scores in the clasp RPD patients, as well as in the precision attachment RPD patients are shown in Table 2. All patients had significantly better after-treatment scores (p <.1); however, better results (i.e., higher OES and lower OHIP-14 and CFQ after-treatment summary scores) were registered in the precision attachment RPD group than in the clasp RPD group (Fig 1, Table 2). Means and standard deviations for the after-treatment OES summary scores in the clasp and the precision attachment RPD patients of different gender are presented in Figure 2. The two-factor ANOVA for the dependent variable: mean OES after treatment summary score and two independent variables: type of RPD retention and gender, with the baseline OES summary score as the covariate (Table 3) revealed significant effect of the factor type of RPD retention, whereas the factor gender showed no significant effect; however, the combination of factors: the type of retention and gender elicited a significant effect. The covariate baseline OES summary score also showed a significant effect. Patients whose dentures were by precision attachments rated their esthetics significantly better (higher scores) than patients with clasp-. Moreover, female patients in the clasp- RPD group rated their esthetics significantly worse than male patients. However, female patients in the precision attachment RPD group rated their orofacial esthetics significantly better than male patients did. The Pearson correlation coefficient between the baseline and the after-treatment OES summary scores was.217, but it was significant (p =.8), indicating that patients who rated better at baseline did the same after treatment. Means and standard deviations for the after-treatment OHIP- 14 summary scores in the clasp and the precision attachment among male and female patients are presented in Figure 3. The two-factor ANOVA for the dependent variable: mean after-treatment OHIP-14 summary score and the two independent variables: the type of RPD retention and gender with the baseline OHIP-14 summary score as the covariate (Table 4) revealed a significant effect of the factor: the type of RPD retention, but not of gender. The mutual effect of factors: the type of RPD retention and gender was not statistically significant. The covariate baseline OHIP-14 summary score showed a significant effect. Patients whose dentures were by precision attachments rated their OHRQoL significantly better (lower scores) than patients with clasp. Female patients in the group clasp- rated their OHRQoL worse than male patients did (higher scores) and, contrarily, female patients in the group precision attachment RPD group rated their OHRQoL better than male patients (lower scores). Although not significant, the mutual effect of gender and the type of RPD retention almost reached the statistically significant level. The Pearson correlation coefficient between the baseline and the after-treatment OHIP-14 summary scores was.32 and was significant (p <.1). Means and standard deviations for the after-treatment CFQ summary scores in the clasp and the precision attachment in male and female patients are presented in Figure 4. The two-factor ANOVA for the dependent variable: after treatment CFQ summary score and the two independent variables: type of RPD retention and gender with the baseline CFQ summary score as the covariate (Table ) revealed significant effect of type of RPD retention and the covariate: baseline CFQ summary score, whereas the factor gender showed no significant effect. The mutual effect of factors: the type of retention and gender elicited significant effect. Female patients whose dentures were by precision attachments rated their chewing function better (lower scores) than female patients with clasp-, whereas male patients rated their chewing function almost equal in the clasp, as well as in the precision attachment. The Pearson correlation coefficient between the baseline and the after-treatment CFQ summary scores was.438 (p <.1) revealing that patients who rated better at the baseline (or worse) did the same after treatment. 4 Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists

5 Peršić et al Patient Assessed RPD Therapy Outcome Table 3 Two-factor ANOVA of the dependent variable after treatment OES summary score and two factors: type of RPD retention (clasps vs. precision attachments) and gender with the baseline OES summary scores as the covariate Dependent variable: after-treatment OES summary scores Source Type III sum of squares df Mean square F p Corrected model a <.1 Intercept <.1 Baseline OES summary scores <.1 Retention of maxillary RPD <.1 Gender NS Retention of maxillary RPD Gender <. Error Total 183, Corrected total a R 2 =.412 (adjusted R 2 =.396). *p <.. **p <.1. NS, not significant. After treatment OHIP summary scores 1 clasps precision attachments Retention of removable denture Gender Female Male Figure 3 Mean values and standard deviations of the after-treatment OHIP-14 summary scores in different types of RPD retention and gender. Discussion Despite various clinical possibilities offered by dental implants, therapy with is still the most common treatment option in partially edentulous patients without posterior abutment teeth. 24 Moreover, despite the registered trend of tooth loss decline in the United States and western European countries, the need for will actually increase as the population ages and increases. 7,8,1,16,2 Therefore, it is very important, though overlooked in the flood of papers related to dental implants, to assess treatment outcomes with RPD therapy, especially from the patients perspective. Patient-based outcomes have been recently widely incorporated in the assessment of oral health components and treatment outcomes. 26 The OHIP has been a widely used instrument for capturing the seven dimensions of OHRQoL. 17,27-29 The shortened version (OHIP-14) meets most clinical needs with good psychometric properties. 23 Therefore, we used the OHIP-14 questionnaire to assess different physical, psychological, and sociological dimensions of RPD therapy. We also used two unidimensional questionnaires: the OES (for patient assessment of self-perceived orofacial esthetics) 18,19 and the CFQ (for assessment of self-perceived chewing function). The OES and the CFQ represented structured unidimensional questionnaires, each capturing only one dimension of orofacial well-being. The structured questionnaires describe much better certain constructs than simple questions that refer to the same construct. We tried to choose as unique a sample as possible, and to exclude possible impacts of younger age groups on RPD wearing, only patients older than 6 years were included. 21,22 Moreover, only patients who already had satisfactory clasp in the mandible (Kennedy class I) were selected to avoid the influence of opposing dentition. Also, only patients with reduced palatal coverage and a U-shaped major connector were included, despite a study claiming that a degree of maxillary palatal coverage did not influence patient satisfaction. 3 Patients with of insufficient quality (insufficient denture retention and stability) were excluded; however, some studies reported that denture quality had minimum effects on OHRQoL The distribution of patients into the C-RPD or PA-RPD group was not random. Most patients chose C-, as they were not willing to undergo tooth preparation. Only a small number of patients (/62) chose C- due to the higher cost of PA-, which they were not willing to pay. The fact that they did not have enough financial support for a particular type of prosthesis could affect their level of satisfaction, because they might think that they received a worse prosthesis. The results of this study showed significantly better aftertreatment outcomes in both the C-RPD and PA-RPD groups. That was attributed to success of RPD therapy in both groups; however, better outcomes (higher OES and lower OHIP-14 and CFQ summary scores) were obtained among the PA-RPD patients compared to the C-RPD patients. Some previous clinical observations from the patients perspective 3 have confirmed those outcomes. Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists

6 Patient Assessed RPD Therapy Outcome Peršić et al Table 4 Two-factor ANOVA of the dependent variable: after-treatment OHIP-14 summary score and two factors: type of RPD retention (clasps vs. precision attachments) and gender with the baseline OHIP-14 summary scores as the covariate Dependent variable: after-treatment OHIP summary scores Source Type III sum of squares df Mean square F p Corrected model 28,649 a 4 627,162 43,392 <.1 Intercept 46, ,13 46,648 <.1 Baseline OHIP-14 summary scores 41, ,23 31,222 <.1 Retention of maxillary RPD 926, ,26 64,7 <.1 Gender 4, ,219 2, NS Retention of maxillary RPD Gender 3,3 1 3,3 3,689.7 NS Error 9, ,43 Total 14822, 1 Corrected total 464, a R 2 =.4 (adjusted R 2 =.32).*p <..**p <.1.NS, not significant. After treatment chewing function questionnaire summary scores 1 clasps precision attachments Retention of removable denture Gender Female Male Figure 4 Mean values and standard deviations of the after-treatment CFQ summary scores in different types of RPD retention and gender. The results related to increased OHRQoL by RPD therapy are in line with other studies. 1,16,21,22,36 However, implant- FPD patients (or implant- RPD patients) reported better OHRQoL outcomes than both groups of RPD wearers examined in the present study The impact of RPD therapy on patients self-reported outcomes considering only the chewing function has not been previously obtained. The multidimensional OHIP questionnaire has been related to social, psychological, and physical outcomes of oral well-being The CFQ has been related only to chewing ability. This is the first time that a unidimensional structured questionnaire consisting of items has been used for the assessment of chewing function outcomes among RPD patients. The structured questionnaire is certainly better than one where only one question is related to the same construct. 19 The OES structured questionnaire was used in this study 18,19 to capture only one dimension related to orofacial esthetics. Some studies reported that besides the type of treatment, gender may also influence clinical outcomes. 21,22 To test the premise, two-way ANOVA was performed with the OHIP-14, the OES, and the CFQ after-treatment summary scores as dependent variables; gender and the type of RPD retention as independent variables, and the baseline summary scores as covariates. A statistically significant effect was observed for the type of RPD retention (better self-reported outcomes were found among the PA-RPD patients compared to the C-RPD group, p <.1), but not of gender (p >.); however, mutual interaction of gender and the type of retention yielded statistically significant effects (p <.1). Female patients in the C-RPD group were significantly more dissatisfied with the esthetic outcome, chewing ability, and OHRQoL than male patients, and vice versa in the PA-RPD group. Female patients were more focused on treatment outcomes and probably therefore overreacted in both assessments. Psychological factors and women s higher sensitivity to their appearance could be responsible for such self-reported esthetic outcomes, which is in accordance with other studies. 21,41,42 Female patients were also more concerned with other treatment outcomes such as their chewing ability and overall OHRQoL. The statistically significant effect (p <.1) of baseline scores noticed in all three questionnaires showed that patients with a worse self-reported oral condition benefited more from RPD therapy; however, positive correlation of the baseline scores (of all three questionnaires) with the after-treatment scores (patients who rated better at baseline did the same after the treatment) can be attributed to a patient s personality traits, expectations, and positive or negative attitudes. 21,22,41-44 The major strength of this study was the assessment of patients self-reported measures related to one multidimensional construct, namely OHRQoL and two unidimensional constructs (structured questionnaires; one for self-assessment of orofacial esthetics and another for self-assessment of chewing function) in two groups of conventional RPD wearers: the C-RPD and the PA-RPD groups. The limitations of the study include unequal and relatively small sample size, some differences in number and position of remaining teeth, some differences considering patient income (patients who could not afford PA- might 6 Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists

7 Peršić et al Patient Assessed RPD Therapy Outcome Table Two-factor ANOVA of the dependent variable: after-treatment CFQ summary score and two factors: type of RPD retention (clasps vs. precision attachments) and gender with the baseline CFQ summary scores as the covariate Dependent variable: after-treatment CFQ summary scores Source Type III sum of squares df Mean square F p Corrected model 112,8 a 4 281,42 17,734 <.1 Intercept 98, ,643 37,719 <.1 Baseline CFQ summary scores 26, ,74 33,189 <.1 Retention of maxillary RPD,338 1,338 6,637 <. Gender 49, ,443 3,11.8 NS Retention of maxillary RPD Gender 128, ,316 8,8 <.1 Error 231, ,871 Total 1666, 1 Corrected total 3427, a R 2 =.329 (adjusted R 2 =.3).*p <..**p <.1.NS, not significant. feel they got an inferior prosthesis) and differences in the educational level. Assessment of patient personality was also not performed. Conclusion Within the limitations of this study, all RPD patients reported improved esthetics, chewing function, and OHRQoL after receiving new dentures with significantly better clinical outcomes in the PA-RPD group than the C-RPD group. Patients with good baseline assessments are also expected to have good aftertreatment assessments, but patients with worse baseline scores benefited more from RPD therapy. Gender by itself yielded no significant effects, but in combination with the factor type of RPD retention, yielded significant effects. Female patients reacted more intensely than male patients, both when more (PA-RPD group) or less satisfied (C-RPD group). Acknowledgments The authors thank the Ministry of Science, Education and Sport, Croatia for funding the University Research Project: Investigation of different prosthodontic and/or implant-prosthodontic therapeutic modalities, materials and TMD. References 1. Dhingra K: Oral rehabilitation considerations for partially edentulous periodontal patients. J Prosthodont 12;21: Budtz-Jörgensen E: Restoration of the partially edentulous mouth a comparison of overdentures, removable partial dentures, fixed partial dentures and implant treatment. J Dent 1996;24: Wolfart S, Müller F, Gerß J, et al: The randomized shortened dental arch study: oral health-related quality of life. Clin Oral Investig 14;18: Zitzmann NU, Hagmann E, Weiger R: What is prevalence of various types of prosthetic dental restorations in Europe? Clin Oral Implant Res 7;18:-33. McKenna G, Allen PF, O Mahony D, et al: The impact of rehabilitation using removable partial dentures and functionally orientated treatment on oral health-related quality of life: a randomised controlled clinical trial. J Dent 1;43: Khan SB, Chikte UM, Omar R: From classroom teaching to clinical practice: experiences of senior dental students regarding the shortened dental arch concept. J Dent Educ 14;78: Vermeulen AH, Keltjens HM, van t Hof MA, et al: Ten-year evaluation of removable partial dentures: survival rates based on retreatment, not wearing and replacement. J Prosthet Dent 1996;76: Tada S, Ikebe K, Matsuda K, et al: Multifactorial risk assessment for survival of abutments of removable partial dentures based on practice-based longitudinal study. J Dent 13;41: Rehmann P, Orbach K, Ferger P, et al: Treatment outcomes with removable partial dentures: a retrospective analysis. Int J Prosthodont 13;26: Behr M, Zeman F, Passauer T, et al: Clinical performance of cast clasp- removable partial dentures: a retrospective study. Int J Prosthodont 12;2: Wöstmann B, Budtz-Jørgensen E, Jepson N, et al: Indications for removable partial dentures: a literature review. Int J Prosthodont ;18: Stegelmann K, Dirheimer M, Ludwig E, et al: Case-control study on the survival of abutment teeth of partially dentate patients. Clin Oral Investig 12;16: Shetty NB, Shetty S, E N, et al: Precision attachments for aesthetics and function: a case report. J Clin Diagn Res 14;8: Chikunov I, Doan P, Vahidi F: Implant- partial overdenture with resilient attachments. J Prosthodont 8;17: Montero J, Castillo-Oyagüe R, Lynch CD, et al: Self-perceived changes in oral health-related quality of life after receiving different types of conventional prosthetic treatments: a cohort follow-up study. J Dent 13;41: Petricevic N, Celebic A, Papic M, et al: The Croatian version of the Oral Health Impact Profile Questionnaire. Coll Antropol 9;33: Slade GD, Spencer AJ: Development and the evaluation of the Oral Health Impact Profile. Community Dent Health 1994;11: Larsson P, John MT, Nilner K, et al: Development of an Orofacial Esthetic Scale in prosthodontic patients. Int J Prosthodont ;23: Persic S, Milardovic S, Mehulic K, et al: Psychometric properties of the Croatian version of the Orofacial Esthetic Scale and suggestions for modification. Int J Prosthodont 11;24:23-33 Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists 7

8 Patient Assessed RPD Therapy Outcome Peršić et al. Persic S, Palac A, Bunjevac T, et al: Development of a new Chewing Function Questionnaire for assessment of a self-perceived chewing function. Community Dent Oral Epidemiol 13;41: Zlataric DK, Celebic A, Valentic MP, et al: A survey of treatment outcomes with removable partial dentures. J Oral Rehabil 3;3: Zlataric DK, Celebic A: Factors related to patients general satisfaction with removable partial dentures: a stepwise multiple regression analysis. Int J Prosthodont 8;21: Rener-Sitar K, Petricevic N, Celebic A, et al: Psychometric properties of Croatian and Slovenian short form of oral health impact profile questionnaires. Croat Med J 8;49: Tanasic IV, Tihacek-Sojic LD, Milic-Lemic AM: Prevalence and clinical effects of certain therapy concepts among partially edentulous Serbian elderly. J Prosthodont 1. doi:.1111/jopr Jones JD, Turkyilmaz I, Garcia LT: Removable partial dentures-treatment now and for the future. Tex Dent J ;127: Locker D: Measuring oral health: a conceptual framework. Community Dent Health 1988;: John MT, Reissmann DR, Feuerstahler L, et al: Exploratory factor analysis of the Oral Health Impact Profile. J Oral Rehabil 14;41: John MT, Reißmann DR, Feuerstahler L, et al: Factor analyses of the Oral Health Impact Profile - overview and studied population. J Prosthodont Res 14;8: John MT, Feuerstahler L, Waller N, et al: Confirmatory factor analysis of the Oral Health Impact Profile. J Oral Rehabil 14;41: Zembić A, Tahmaseb A, Wismeijer D: Within-subject comparison of maxillary implant-supported overdentures with and without palatal coverage. Clin Implant Dent Relat Res 1;17: Inoue M, John MT, Tsukasaki H, et al: Denture quality has a minimal effect on health-related quality of life in patients with removable dentures. J Oral Rehabil 11;38: Zlataric DK, Celebic A: Treatment outcomes with removable partial dentures: a comparison between patient and prosthodontist assessments. Int J Prosthodont 1;14: Petricevic N, Celebic A, Rener-Sitar K: a 3-year longitudinal study of quality-of-life outcomes of elderly patients with implant- and tooth-supported fixed partial dentures in posterior dental regions. Gerodontology 12;29:e96-e Alfadda SA: The relationship between various parameters of complete denture quality and patients satisfaction. J Am Dent Assoc 14;14: den Haan R, Battistuzzi PG, Witter DJ, et al: Semi-precision attachments for cast metal frame removable partial dentures. Ned Tijdschr Tandheelkd 11;118: Reissmann DR, Schierz O, Szentpétery AG, et al: Improved perceived general health is observed with prosthodontic treatment. J Dent 11;39: Persic S, Celebic A: Influence of different prosthodontic rehabilitation options on oral health-related quality of life, orofacial esthetics and chewing function based on patient-reported outcomes. Qual Life Res 1;24: Persic S, Palac A, Vojvodic D, et al: Initial effects of a treatment by fixed partial dentures supported by mini dental implants from a patient s point of view. Coll Antropol 14;38: Kranjcic J, Mikus A, Mehulic K, et al: Knowledge and awareness of dental implants among elderly people in Croatia. J Prosthodont 1;24: Persic S, Celic R, Vojvodic D, et al: Oral health related quality of life (OHRQoL) in different types of mandibular implant overdentures in function over 3 years. Int J Prosthod 16;447 (in press). 41. Celebic A, Zlataric DK, Papić M, et al: Factors related to patient satisfaction with complete denture therapy. J Gerontol A Biol Sci Med Sci 3;8:M948-M Zlataric DK, Celebic A, Valentic MP, et al: The satisfaction with the removable partial denture therapy in the Croatian adult population. Coll Antropol ;24: Fouda SM, Al-Attar MS, Virtanen JI, et al: Effect of patient s personality on satisfaction with their present complete denture and after increasing the occlusal vertical dimension: a study of edentulous Egyptian patients. Int J Dent 14;14: Stipetic J, Celebic A, Jerolimov V, et al: The patient s and the therapist s evaluation of bridges of different materials and age. Coll Antropol ;24(Suppl 1): Journal of Prosthodontics (1) 1 8 C 1 by the American College of Prosthodontists