Shear bond strength of the ceramic veneer to additively manufactured titanium

OBJECTIVES

The objective of this in vitro study was to evaluate the shear bond strength between the ceramic veneer and additively manufactured titanium with different surface treatments, and to compare with milled titanium. Also, to characterize the surface and the presence of an α-case layer of additively manufactured and milled titanium.

MATERIAL AND METHODS

Sixty additively manufactured titanium grade 23, and 20 milled titanium grade 4 cylindrical specimens were divided into four groups based on surface treatments, air-particle abrasion and grinding. After ceramic veneering half of each group were thermocycled. The bond strength was analyzed using a shear bond strength test. The surfaces were analyzed using interferometry and scanning electron microscopy.

RESULTS

The grinding procedure and air-particle abrading pressure had no significant effect on the shear bond strength (p = .264 and p = .344). Thermocycling showed a tendency towards an effect but not significant (p = .052). The group with the highest air-abrading pressure showed the highest surface roughness. No presence of an α-case layer was detected in any of the groups.

CONCLUSION

Additively manufactured titanium grade 23 may be veneered with ceramics without prior grinding of the surfaces.

Residual stress associated with crystalline phase transformation of 3-6 mol% yttria-stabilized zirconia ceramics induced by mechanical surface treatments

Monolithic dental prostheses made of 3-6 mol% yttria-stabilized zirconia (3-6YSZ) have gained popularity owing to their improved material properties and semi-automated fabrication processes. In this study, we aimed to evaluate the influence of mechanical surface treatments, such as polishing, grinding, and sandblasting, on the residual stress of 3-6YSZ used for monolithic prostheses in association with crystalline phase transformation. Plate specimens were prepared from five dental zirconia blocks: Aadva Zirconia ST (3YSZ), Aadva Zirconia NT (6YSZ), Katana HT (4YSZ), Katana STML (5YSZ), and Katana UTML (6YSZ). The specimens were either polished using 1, 3, or 9 μm diamond suspensions, ground using 15, 35, or 55 μm diamond discs, or sandblasted at 0.2, 0.3, or 0.4 MPa. The residual stress, crystalline phase, and hardness were analyzed using the cosα method, X-ray diffraction (XRD), and Vickers hardness test, respectively. Additionally, we analyzed the residual stress on the surfaces of monolithic zirconia crowns (MZCs) made of 4YSZ, 5YSZ, and 6YSZ, which were processed using clinically relevant procedures, including manual grinding, followed by polishing using a dental electric motor on the external surface, and sandblasting on the internal surface. Residual stress analysis demonstrated that grinding and sandblasting, particularly the latter, resulted in the generation of compressive residual stress on the surfaces of the plate specimens. XRD revealed that the ground and sandblasted specimens contained a larger amount of the rhombohedral phase than that of the polished specimens, which may be a cause of the residual stress. Sandblasting significantly increased the Vickers hardness compared to polishing, which may possibly be due to the generation of compressive residual stress. In the case of MZCs, compressive residual stress was detected not only on the sandblasted surface, but also on the polished surface. The difference in the residual stress between the plate and crown specimens may be related to the force applied during the automated and manual grinding and polishing procedures. Further studies are required to elucidate the effects of the compressive residual stress on the clinical performance of MZCs.

Evaluation of fit and accuracy of single crowns fabricated from self-glazed zirconia compared with milled zirconia

STATEMENT OF PROBLEM

Self-glazed zirconia is a novel dental material fabricated with a combination of subtractive and additive manufacturing techniques. However, how the marginal and internal fit of these restorations compare with conventionally fabricated zirconia is unclear.

PURPOSE

The purpose of this in vitro study was to evaluate the marginal and internal fit and internal accuracy of single crowns made from self-glazed zirconia compared with those made from milled zirconia.

MATERIAL AND METHODS

A metal die was scanned, and a crown was designed using a computer-aided-design program. The computer-aided-manufacturing milling method (conventional technique) was used to produce 10 zirconia crowns, and additive manufacturing was used to produce 10 self-glazed zirconia crowns. Internal and marginal fit measurements were made by using the silicone replica method; marginal fit was also measured by using the direct-view technique. An independent t test was performed to compare both types of crowns and test the null hypothesis (α=.05).

RESULTS

For the occlusal, internal, and total mean distances, significant differences were found between self-glazed and milled zirconia crowns (P<.001). With the direct-view technique, a significant difference (P=.004) between the 2 techniques was found in the marginal area. The accuracy for the axial and occlusal areas combined for self-glazed and milled zirconia was 27 μm and 49 μm, respectively.

CONCLUSIONS

Both techniques produced crowns with clinically acceptable marginal and internal fit. The self-glazed zirconia crowns had higher accuracy of internal fit than milled zirconia crowns.

Comparison of porcelain veneer fracture in implant-supported fixed full-arch prostheses with a framework of either titanium, cobalt-chromium, or zirconia: An in vitro study

Objectives

The aim of this study was to compare porcelain veneer strength on screw‐retained implant‐supported fixed full‐arch prostheses with a framework of either milled titanium (Ti), cobalt–chromium (CoCr), and yttria‐stabilized zirconia (Y‐TZP) in an in vitro loading model.

Materials and Methods

Fifteen screw‐retained maxillary implant‐supported full‐arch prostheses (FDP), five each of Ti, CoCr, and Y‐TZP frameworks with porcelain veneers were included. All FDPs were subjected to thermocycling before loading until fracture of the veneer. The load was applied at the distal fossa of the occlusal area of the pontic replacing 24. Fracture loads were analyzed, and the fracture quality was assessed. Statistical analysis on the fracture load was performed using Kruskal–Wallis test. The statistical significance was set at p < .05.

Results

There was no statistical significance found between the groups regarding fracture load. The highest and lowest load was seen within the CoCr FDP, varying between 340 and 1484 N. Different types of fracture appearances were seen. The Y‐TZP FDPs had a higher number of fractures locally in the loaded area while CoCr and Ti more often showed cracks in the anterior region, at a distance from the loaded area.

Conclusions

Within the limitations of this study, the conclusion was that framework material may affect the fracture behavior of maxillary full‐arch bridges; however, there were no differences in veneer fracture strength when frameworks of Ti, CoCr, or Y‐TZP were compared.

Influence of crystalline phase transformation induced by airborne-particle abrasion and low-temperature degradation on mechanical properties of dental zirconia ceramics stabilized with over 5 mol% yttria

Monolithic dental prostheses fabricated from 5 mol% yttria-stabilized zirconia (5YZ) have been developed to improve the translucency of conventional 3 mol% yttria-stabilized zirconia. In this study, we aimed to evaluate the influence of airborne-particle abrasion (APA) and low-temperature degradation (LTD) on the mechanical properties of 5YZ in association with the crystalline phase transformation. In total, 120 disc-shaped specimens of two brands of 5YZ (Lava Esthetic and Katana UTML) were prepared. The specimens were divided into four groups (n = 15 for each group): (i) control, (ii) APA, (iii) LTD, and (iv) APA + LTD groups. APA was performed with 50 μm alumina particles, and LTD was induced by autoclaving at 134 °C for 50 h. The biaxial flexural strength of the specimens was assessed using a piston-on-three-ball test according to ISO 6872:2015, and Vickers hardness was determined using a microhardness tester. The crystalline phase was analyzed by the Rietveld refinement of X-ray diffraction patterns. APA significantly increased the flexural strength of the Lava Esthetic specimens, whereas LTD hardly affected the strength of both materials. APA and APA + LTD significantly increased the Vickers hardness of both materials. According to Rietveld analysis, the pseudocubic phase was predominant in both materials, i.e., 66 mass% and 81 mass% in the Lava Esthetic and Katana UTML specimens, respectively. APA induced the rhombohedral phase at approximately 37 mass% in both materials, while LTD induced the monoclinic phase at 2.8 mass% in the Lava Esthetic specimens and 0.9 mass% in the Katana UTML specimens. APA + LTD weakly affected the amount of the rhombohedral phase but slightly increased the amount of the monoclinic phase. These findings suggest that APA may improve the mechanical properties of 5YZ, particularly hardness, via the generation of the rhombohedral phase. In contrast, the influence of LTD on the mechanical and microstructural properties of 5YZ was limited.

The effects of atomoxetine on emotional control in adults with ADHD: An integrated analysis of multicenter studies

Purpose:

To investigate the effects of atomoxetine on emotional control in adults with ADHD.

Methods:

We performed an integrated analysis using individual patient data pooled from three Eli Lilly-sponsored studies. An integrated analysis can be viewed as a meta-analysis of individual patient-level data, rather than study-level summary data.

Results:

Two populations were identified: a large sample of patients with pre-treatment baseline data (the “overall population”; n = 2846); and a subset of these patients with placebo-controlled efficacy data from baseline to 10 or 12 weeks after initiating treatment (the “placebo-controlled population”; n = 829). At baseline, in the overall population, ∼50% of ADHD patients had BRIEF-AS (Behavior Rating Inventory of Executive Function-Adult Version Self-Report) Emotional control subscores between 21 and 30, compared with ∼10% of normative subjects in the BRIEF-A manual. At endpoint, in the placebo-controlled population, atomoxetine led to a small (effect size 0.19) but significant (P = 0.013) treatment effect for emotional control. The effect size was 0.32 in patients with BRIEF-AS Emotional control scores > 20 at baseline. Improvements in emotional control correlated with improvements in the core ADHD symptoms and quality-of-life.

Discussion:

As deficient emotional control is associated with impaired social, educational and occupational functioning over and above that explained by core ADHD symptoms alone, improvements in emotional control may be clinically relevant.

Conclusion:

At baseline, adults with ADHD were more likely to have impaired emotional control than normative subjects. In the adult ADHD patients, atomoxetine treatment was associated with improvements in emotional control, as well as in core ADHD symptoms and quality-of-life.

A systematic review on the accuracy of manufacturing techniques for cobalt chromium fixed dental prostheses

Purpose

To compare the fit and assess the accuracy of tooth-supported single and multi-unit FDPs in cobalt chromium fabricated using different manufacturing techniques.

Materials and methods

A systematic search was performed in three databases; PubMed, Scopus, and Web of Science, using clearly specified search terms and inclusion criteria. The search yielded 1071 articles and included 18 articles in the analysis. Data regarding the fit analyses and the methods of manufacturing were extracted and the accuracy was defined as the fit result minus the pre-set cement spacer. Internal gap (IntG) was the mean of all the internal measuring points and total gap (TotG) was the mean of all measuring points (marginal, cervical, chamfer, axial, occlusal).

Results

The total gap results for fit and accuracy irrespective of manufacturing technique were 96 μm and 54 μm for single crowns, 107 μm and 54 μm for multi-unit FDPs, and 98 μm and 54 μm for both single crowns and multi-unit FDPs combined. For total gap of single crowns soft milling had the highest accuracy, for multi-unit FDPs additive manufactured restorations had the highest accuracy. With the results grouped by impression technique, the accuracy for total gap was highest for digital impressions and lower for conventional impressions.

Conclusions

Due to the inherent limitations of this systematic review, it still remains unclear what effect the manufacturing technique has on the fit of FDPs. However, the descriptive results suggest that the marginal fit of cobalt chromium FDPs is not negatively affected by the manufacturing technique.

A systematic review on the accuracy of zirconia crowns and fixed dental prostheses

Purpose

The aim of this study was to review the fit and assess the accuracy of tooth-supported single and multi-unit zirconia fixed dental prostheses.

Background

The fit of zirconia restorations has been reported in several studies, but the accuracy of the manufacturing process is seldom discussed or used when drawing conclusions on the fit.

Materials and methods

A literature search of articles published in PubMed between 2 March 2013 and 1 February 2018 was performed using clearly defined inclusion and exclusion criteria. 841 articles were found and 767 were excluded after screening the title and abstract. After full-text analysis another 60 articles were excluded which left 14 articles to be included for data extraction. Fit was the mean of distances reported in the studies and accuracy was the fit minus the pre-set spacer

Results

For marginal gap of single crowns and multi-unit FDPs combined, the fit was 83 μm and the accuracy was 59 μm. The internal gap fit was 111 μm and the accuracy 61 μm. For the total gap, the fit was 101 μm, and the accuracy of the zirconia restorations was 53 μm.

Conclusions

Within the limitations of the present systematic review the fit of zirconia single crowns and multi-unit FDPs may be regarded as clinically acceptable, and the accuracy of the manufacturing of zirconia is ∼60 μm for marginal, internal, and total gap. Also, digital impressions seem to be associated with a smaller gap value.

Comparison of the 3D triple-scan protocol and the impression replica technique for 3-unit tooth-supported fixed dental prostheses

Objective: The aim of this study was to compare the fit measurements from the 3 D triple-scan protocol and the impression replica technique, by measuring the fit of three-unit tooth-supported fixed dental prostheses.

Materials and methods: The results from an earlier study using the triple-scan protocol were compared to results from the impression replica technique for absolute marginal gap, cervical area gap and internal gap.

Results: There were no differences for cervical area gap or internal gap, but for absolute marginal gap the impression replica technique obtained significantly smaller fit values.

Conclusion: The impression replica technique and the triple-scan protocol may both be used to measure the fit of tooth-supported restorations. However, the scanner used for the triple-scan protocol must be able to obtain scan points at the outermost edge of the restorations when used for absolute marginal gap.

Fit of cobalt-chromium implant frameworks before and after ceramic veneering in comparison with CNC-milled titanium frameworks

Computer-aided design/computer-aided manufacturing fabrication of implant-supported frameworks is a standard procedure, and the use of ceramic-veneered cobalt-chromium alloys is increasing. However, no data are available concerning the precision of fit of these frameworks and the impact on the fit of the veneering procedure. The aim of this study was to evaluate the fit of computer numeric-controlled-milled cobalt-chromium and titanium implant frameworks for edentulous maxillas, provided with six implants. An additional aim was to evaluate the effect of ceramic veneering on the fit of the cobalt-chromium frameworks. Ten stone casts simulating an edentulous maxilla provided with six dental implants and abutments were produced. One computer numeric-controlled-milled cobalt-chromium framework and one titanium framework were fabricated for each stone cast. Each stone cast and corresponding titanium and cobalt-chromium framework was measured with a coordinate measuring machine in the three-dimensional (X axis, Y axis, and Z axis) directions. Both milled titanium and cobalt-chromium frameworks presented a good fit in the vertical plane (Z axis), 5.3 µm for titanium frameworks and 4.6 µm for the cobalt-chromium frameworks. The titanium frameworks showed a statistically significant smaller mean degree of misfit in the horizontal plane, X (5.0 µm) and Y (2.8 µm) axes as compared with the cobalt-chromium frameworks presenting a mean deviation of 13.5 µm in X axis and 6.3 µm in Y axis (P < 0.001). After ceramic veneering of the cobalt-chromium frameworks, the horizontal distortion significantly decreased from 13.5 to 9.7 µm in X axis (P = 0.007) and from 6.3 to 4.4 µm in Y axis (P = 0.017). The fit of both titanium and cobalt-chromium frameworks was very good. There were small but significant differences in fit between the titanium and cobalt-chromium frameworks, but the difference is of no clinical significance. The ceramic veneering resulted in a minor but significant improvement of the fit for the cobalt-chromium frameworks.

A 5-year retrospective study of cobalt-chromium-based fixed dental prostheses

PURPOSE

The aim of this retrospective study was to evaluate the 5-year clinical outcome for ceramic veneered cobalt-chromium (Co-Cr) fixed dental prostheses (FDPs) fitted in a private clinical setting.

MATERIALS AND METHODS

All patients treated consecutively with Co-Cr FDPs from January 2000 to November 2005 were included, and complications were registered. Patient records were examined for details on the restorations and abutment teeth. A total of 149 patients with 201 FDPs, 1,135 units, and 743 abutment teeth were recorded.

RESULTS

Of the 149 patients, 122 (82%) were followed for 5 years. Complications occurred in 34 patients (23%) and 38 FDPs (19%). The most frequent were caries (6.7% of patients, 5% of FDPs, 2.2% of abutments) and cement failure (6.7% of patients, 5% of FDPs, 3.1% of abutments). Cohesive ceramic fractures occurred in only 7 FDPs (3.5% of FDPs, 0.7% of units). No adhesive ceramic fractures were recorded. The 5-year cumulative rates for success and survival were 83.8% and 92.8%, respectively.

CONCLUSIONS

Co-Cr FDPs appear to be a promising prosthodontic treatment modality, presenting low incidence of complications and a high survival rate during the first 5 years of function. However, long-term randomized controlled studies are necessary to confirm these findings.

A 5-year retrospective study of cobalt-chromium-based single crowns inserted in a private practice

The aim of this retrospective study was to evaluate the clinical performance of cobalt-chromium (Co-Cr) single crowns. Ninety restorations were placed in 55 patients, and follow-up examinations were performed annually for 5 years. Six patients (8 crowns) were regarded as dropouts. During the follow-up period, 15 (17%) crowns/abutment teeth experienced some type of complication; 8 (9%) of these were regarded as failures. The cumulative survival rate was estimated at 90.3% over 5 years, though only 3 (3%) crowns had complications that could be related to the crown material. The results suggest that Co-Cr single crowns are a promising alternative to other alloys used in fixed prosthodontics.

A comparison between the Beck Depression Inventory (BDI) and the self-rating version of the Montgomery Asberg Depression Rating Scale (MADRS)

BACKGROUND

The Beck Depression Inventory BDI is the most often used self-rating instrument for depressive symptoms. In the present study, the BDI was compared with a self-rating version of the Montgomery Asberg Depression Rating Scale (MADRS-S) in 86 psychiatric patients with mainly affective and anxiety disorders.

METHODS

The patients were interviewed with the SCID-I Interview for a DSM-IV Major depression, and self-assessed the BDI and the MADRS. They were rated to have either mild, moderate or severe depressive symptomatology. After recovery, criteria for DSM-IV Personality disorders were self-assessed.

RESULTS

The instruments were about equal in differentiating between different Axis-I diagnoses and did not differ according to sensitivity to change during antidepressive treatment. Although the scales were highly intercorrelated (r=0.869), the BDI was demonstrated to tap more maladaptive personality traits compared to the MADRS-S.

LIMITATIONS

Because the sample consisted of psychiatric patients with prominent psychiatric symptomatology, the discriminative power of the BDI and the MADRS-S should be further evaluated in a sample with milder symptoms.

CONCLUSIONS

The MADRS-S is equivalent to the BDI as a self-assessment instrument for depression, but the MADRS-S focuses on core depressive symptoms, and is less influenced by maladaptive personality traits.

Associations between plasma glucose and DSM-III-R cluster B personality traits in psychiatric outpatients

Associations between personality traits, measured with the Karolinska Scales of Personality, the Impulsiveness subscale from the Impulsiveness, Venturesomeness and Empathy (IVE) Inventory, and with self-assessed personality traits and disorders (SCID-II Screen Questionnaire), and plasma insulin, glucagon and glucose, respectively, were explored in a sample of 101 psychiatric outpatients of both sexes. No relationships between the peptide hormones and personality measures were found. However, fasting glucose values, which were all essentially within the normal biological variation, were significantly related to several personality measures. For males, a low blood glucose was associated with low stable general level of functioning, with high IVE Impulsiveness, and with self-assessed histrionic and narcissistic traits. High number of self-assessed personality traits for all cluster B personality disorders was strongly associated with high IVE Impulsiveness. The results of the present study support the generalizability of earlier findings from alcoholic impulsive offenders: in males, low blood glucose is associated with an extrovert and impulsive, acting-out behavior that includes the breaking of societal norms and rules. In contrast, for females a positive relationship between fasting glucose and self-assessed histrionic personality traits was found. Because no association between global level of functioning and glucose was found in women, these personality traits may not necessarily be maladaptive, as was the case for males.

Assessment of maladaptiveness: a core issue in the diagnosing of personality disorders

Although an operationalized and commonly accepted definition of maladaptiveness is lacking, the delineation of personality traits as being adaptive or maladaptive is essential in diagnosing personality disorders (PDs). A way to explore the meaning of maladaptiveness is to compare how patients from all DSM-III-R PDs relate to different traits and dimensions of various dimensional models of personality. In the present study, the Karolinska Scales of Personality (KSP) were used in a sample of 94 psychiatric outpatients who were assessed according to severity of maladaption and according to type of predominant cluster type of deviant traits. Only one of four factors of the scores of the KSP subscales, "Interpersonal Aversiveness," was related to degree of maladaption, indicating high detachment, suspicion, irritability, dysphoria, and low socialization as core features of maladaptiveness. Three subscales of the KSP Socialization were all associated with maladaptiveness. However, one subscale, "Childhood Adjustment," was also related to the predominant cluster type of personality pathology.

What patient characteristics make therapists recommend psychodynamic psychotherapy or other treatment forms?

In order to study factors that psychodynamic therapists considered to be important for recommendation of treatment, psychiatric diagnoses (DSM-III-R Axes I and II and the GAF) as well as character traits assessed by the Karolinska Psychodynamic Profile (KAPP) were retrospectively assessed in interview case-notes of patients applying for psychodynamic psychotherapy. Recommendation of psychotherapy was predicted by the absence of a personality disorder and high GAF scores, but not by the presence of a psychiatric syndrome. The KAPP differentiated between patients with and without disorders on Axis II, but not on Axis I. Patients who were recommended psychodynamic psychotherapy were healthier on all central KAPP variables compared to those who were recommended other treatments, and they were also characterized by predominantly neurotic personality organization, with inhibition as the most prominent defence.

Determinants of self-rating and expert rating concordance in psychiatric out-patients, using the affective subscales of the CPRS

To investigate in more detail concordance between the recently developed Comprehensive Psychopathological Rating Scale (CPRS) and the recently developed Self-Rating Scale for Affective Syndromes (CPRS-S-A), a total of 101 psychiatric out-patients were assessed using these procedures and a diagnostic interview according to DSM-III-R. Depressive and anxiety syndromes were the most common diagnoses on Axis I. Approximately one-third of the patients had a diagnosis of clinical personality disorder on Axis II. The majority of the patients were assessed as predominantly manifesting either Cluster B or Cluster C traits. In general, the correlation between self- and expert-ratings was strong (0.83 for the Montgomery-Asberg Rating Scale (MADRS) depression subscale and 0.76 for the Brief Scale for Anxiety (BSA) anxiety subscale), but it tended to be weaker in the group of patients with clinical personality disorders. The correlation between the two ratings was also weaker in the group with predominantly Cluster B character traits than in the group with predominantly Cluster C traits or the group with no predominant traits, and weaker in the depressive group than in the anxiety group. However, personality disorder diagnoses were over-represented in the depressive group. The weaker correlations in the groups mentioned above may have been attributable to psychological factors and qualitative differences in cognitive and communicative style. The CPRS-S-A is considered to be a useful and reliable instrument for quantitative rating of symptoms in out-patients. Our results highlight the potential value of using appropriate self-assessment forms as complementary tools in clinical practice and research.

Improving the usefulness of the Karolinska Psychodynamic Profile in research: proposals from a reliability study

The interrater reliability of data obtained by use of the Karolinska Psychodynamic Profile (KAPP) was tested among 60 women seeking treatment for drinking problems. The first rater had a psychodynamic background but was minimally trained rating the KAPP subscales and performing KAPP interviews. Independent, blind ratings of audiotaped interviews by an experienced KAPP rater revealed that 8 of the subscales obtained satisfactory reliability, whereas 6 subscales showed unsatisfactory reliability. Furthermore, data for one subscale (normopathy) showed a zero correlation between raters, probably due to the novelty of the construct. Additionally 3 subscales related to bodily aspects were of little clinical significance among the present study group. Our data were compared with data from previous KAPP reliability studies, and the reasons for similarities and discrepancies of results are discussed.

A new self-rating scale for depression and anxiety states based on the Comprehensive Psychopathological Rating Scale

Self-assessment scales have long been used in psychiatric research even if their validity has often been questioned, one reason being poor the concordance of expert ratings. In clinical practice the use of rating scales is restricted, since they are considered to be time-consuming and perhaps even to disrupt the clinician's rapport with the patient. In the present study, a self-assessment scale, the CPRS Self-rating Scale for Affective Syndromes (CPRS-S-A), was constructed by re-phrasing in a self-rating format 19 items from the original Comprehensive Psychopathological Rating Scale (CPRS) and covering depression, anxiety and obsessional symptoms. In a group of 30 patients with depression syndromes and anxiety syndromes, the CPRS-S-A and the original CPRS were both used on 2 occasions. The patient's Global Assessment of Functioning scores ranged from 30 to 76 (mean 58), which suggests a moderate severity of illness, as does the fact that the majority were outpatients. There was a high degree of concordance between the instruments for most items and for the scores on the subscales for both diagnostic groups (i.e., the Montgomery-Asberg Depression Rating Scale and the Brief Anxiety Scale, which are both subscales drawn from the CPRS). The time taken to complete the CPRS-S-A varied from 5 to 30 min (mean 19 min for depressive and 16 min for anxiety patients on the first occasion, 13 min for both groups on the second), and the self-rating procedure was readily accepted by both groups of patients. The CPRS-S-A would thus seem to be a promising instrument for quantitative rating of symptoms in ambulatory patients, both in clinical practice and in research.