California Dental Association Criteria Research Articles

Clinical Performance of Minimally Invasive Monolithic Ultratranslucent Zirconia Veneers: A Case Series up to Five Years of Follow-up

SUMMARY There is a lack of reports in the literature on the long-term clinical performance of ultratranslucent zirconia, especially considering its use in manufacturing monolithic veneers. The purpose of this case series is to describe the aesthetic treatment steps of three patients with minimally invasive ultratranslucent zirconia veneers and to report the clinical findings up to five years. Three patients (woman: 2, man: 1; mean age: 30 years) unsatisfied with their dental aesthetics sought dental treatment. The treatment plan involved cementing ultratranslucent zirconia veneers. Air-abrasion was performed on the internal surface of zirconia with alumina particles coated by silica (silicatization), followed by silane and adhesive applications for the adhesive cementation. All veneers were adhesively cemented to enamel with resin cement (Variolink Esthetic, Ivoclar). The patients were clinically evaluated annually considering the Ryge modified/ California Dental Association criteria. After a mean follow-up of 4.33 years (4-5 years), a survival rate of 100% was detected for the 28 minimally invasive ultratranslucent zirconia veneers cemented in the 3 patients. There were no absolute failures such as debonding, veneer fracture, or secondary caries. Superficial marginal discoloration was observed in one element (maxillary left lateral incisor) of one patient. Ultratranslucent zirconia is a viable option for manufacturing veneers due to its excellent clinical performance and longevity. However, further long-term clinical studies are essential to consolidate this material as an option for esthetic restorations.

Clinical outcomes of single crown and 3-unit bi-layered zirconia-based fixed dental prostheses: An upto 6- year retrospective clinical study: Clinical outcomes of zirconia FDPs

ObjectivesThe aim of this retrospective clinical study was to evaluate the survival and the occurrence of technical and biological complications in bi-layered zirconia-based (Zi) single crown and 3-unit fixed dental prostheses (FDPs). Also, the study aimed to analyze the effects of tooth vitality (vital versus non-vital), abutment location (anterior versus posterior), and luting cement (self-adhesive resin versus resin-reinforced glass ionomer) on clinical outcomes. MethodsA total of 147 prostheses (in 94 patients) placed by undergraduate dental students in a university dental center during the period 2015–2021 were examined clinically using modified United States Public Health Service (USPHS) and California Dental Association (CDA) criteria. The mean duration of follow-up was 37 months (range, 6 - 63 months) for the single crowns (n = 77) and 25 months (range, 6 - 68 months) for the 3-unit FDPs (n = 70). Data were descriptively analyzed to determine the types and rates of complications based on USPHS and CDA criteria. The Kaplan-Meier survival estimation method was used to determine the cumulative survival and success rates of the prostheses (α=0.05). Differences in clinical outcomes (survival or failure) according to tooth vitality, luting cement, and location were statistically analyzed using cross-tabulations and Х2 test (α=0.05). ResultsThe Kaplan-Meier cumulative survival rate was estimated as 96% for the Zi 3-unit FDPs after 5.5 years, and 90% for the Zi single crowns after 4.8 years. The 5-year estimated success rate was 68% for both 3-unit FDPs and single crowns. Seven (9.1%) 77Zi single crowns and 70 2 (2.9%) Zi 3-unit FDPs were recorded as failures with occlusal roughness being the most commonly-observed complication (crowns: 4 [5.6%]; 3-unit FDPs: 8 [11.4%]). In terms of clinical outcomes, statistically significant differences were found between all included vital and non-vital teeth (p = .006), and cement types (p = .028). Taking single crowns alone, significant differences in clinical outcomes according to tooth vitality were noted (p = .036), but not for PFDPs. The location of the prostheses did not produce any significant differences in the clinical outcomes, for both prostheses types independently or combined (p > .05). ConclusionsThe estimated cumulative survival rates in this study for single crowns and 3-unit Zi FDPs concurred with the ranges reported in systematic reviews. Zi-based prostheses on vital teeth produced better clinical outcomes than those placed on non-vital teeth, and type of luting cement influenced the final clinical outcome. Clinical significanceZi crowns and 3-unit PFDPs fabricated using the specific CAD-CAM system used in the controlled environment of this study showed good clinical performance with minimal veneer porcelain chipping. Root canal treated teeth seem to be at higher risk for failure of Zi prostheses compared with vital teeth.

Translucent Zirconium Dioxide and Lithium Disilicate: A 3-Year Follow-up of a Prospective, Practice-Based Randomized Controlled Trial on Posterior Monolithic Crowns

To systematically evaluate and compare the clinical performance of lithium disilicate (LDS)- and zirconium dioxide (ZrO2)-based ceramic monolithic crowns in the posterior dentition. Treatment was administered by two experienced general dental practitioners in two public dental health care clinics. Forty-four patients received 60 crowns randomized to be either LDS or ZrO2 and cemented with resin cement. Evaluations were performed after 3 years using California Dental Association criteria. The mean follow-up time was 40 months (range: 31 to 50). No crown fractured during the observation time, and no chip-off fractures occurred. The success rate for ZrO2 was 80%, and the survival rate was 93.3%. For LDS, the success rate was 89.7%, and the survival rate was 100%. Survival after 3 years for all crowns together was 96.6%, and success was 84.7%. There was no significant difference between the two materials. Crowns made of monolithic translucent ZrO2 and LDS show equal and promising clinical results from a short-term perspective. There seems to be a difference between how patients and professionals rate crowns concerning esthetics (color and shape), with patients rating the restorations more favorably.

Evaluation of the clinical behavior of 2 different materials for implant-supported interim fixed partial prostheses: A randomized clinical trial

Statement of problemClinical studies about interim implant-supported prostheses made of polymethylmethacrylate (PMMA) and polyoxymethylene (POM) have been limited to clinical reports or studies on the survival of implants subjected to immediate loading without evaluating the influence of the material used. PurposeThe purpose of this randomized clinical trial was to evaluate the clinical performance of posterior resin interim implant-supported fixed partial dentures (FPDs) made of 2 different computer-aided design and computer-aided manufactured (CAD-CAM) materials: PMMA and POM. Material and methodsA total of 21 participants received 49 interim implant-supported FPDs. The same participant received the PMMA as part of the control group and the POM as part of the experimental group. The restorations were evaluated at 1 week and 3 and 6 months after their placement, using the California Dental Association (CDA) quality-evaluation index. Their functional wear and color stability were also evaluated. Data were analyzed by using nonparametric statistics (α=.05). ResultsThe CDA criteria showed that the PMMA group performed better than the POM group in the surface and color parameter (P<.05). Fractures at the implant connection level were observed in 10 prostheses. The number of fractures was significantly higher in internal conical connection implants (P<.05). The statistical analysis of color stability showed values of ΔE*ab of 7.18 for PMMA and 8.58 for POM, without significant differences between materials. Concerning the wear evaluation, a significant increase in the wear of both materials was found at 6 months of functioning (P<.05). No significant differences were found within materials. ConclusionsWithin a 6-month observation period, PMMA interim implant-supported FPDs performed better than POM in the surface and color parameter. Entirely polymer posterior implant-supported FPDs with internal conical connection implants appear to be more susceptible to fracture.

Clinical evaluation of monolithic zirconia crowns for posterior teeth restorations.

Although all-ceramic crowns have excellent biocompatibility and esthetic appearance, chipping may occur. The mechanical properties of monolithic zirconia restorative material are superior to those of all-ceramic restorative materials, and chipping caused by chewing hard foods could be avoided. This study aimed to evaluate the clinical efficacy of monolithic zirconia crowns for posterior teeth restorations.A total of 46 patients requiring posterior teeth restorations involving 49 teeth were treated with monolithic zirconia crown procedure. The treatment results were evaluated according to the modified California Dental Association criteria immediately after the procedure, and at 2, 24, 48, and 96 weeks after the procedure. The plaque index, gingival index, probing depth, crown marginal integrity, and attrition of the abutment teeth, antagonist teeth, corresponding contralateral teeth, and antagonist of the corresponding contralateral teeth were assessed. The patients were followed for up to 96 weeks.The marginal adaptation results of all 46 patients were evaluated as excellent, resulting in an excellent rate of 100%. Regarding the crown color match, only 3 cases (6.1%) were evaluated as acceptable. Marginal adaptation, anatomic form, crown margin integrity, color match, and gross fracture did not show significant differences compared with the different time points (P = .999). Surface texture at different time did not change significantly (P = .807). During the 96-week follow-up, 1 crack in the antagonist teeth was found in 1 patient. There were no significant differences in wear of the antagonist teeth at different time points (P = .972). The rate of “excellent” evaluation for crown restorations was 93.9% to 100%.The monolithic zirconia crown had no detectable adverse effects on the periodontal tissues, and the antagonist teeth attrition was small. Therefore, it has good potential in the clinical application of posterior teeth restorations in the short term.

Periodontal outcome and additional clinical quality criteria of lithium-disilicate restorations (Empress 2) after 14years.

To evaluate the clinical quality of tooth-supported crowns (SCs), implant-supported crowns (ISCs), and fixed dental prosthesis (FDPs) made of a lithium-disilicate glass-ceramic framework material (IPS Empress 2, Ivoclar Vivadent) after long-term use. Between 1997 and 1999, 184 restorations (106 SCs, 32 ISCs, 33 FDPs, 13 diverse restorations) were placed in 73 patients. In 2012/2013, all patients with functioning restorations were invited to participate in a clinical follow-up examination. To investigate the clinical quality, modified California Dental Association (CDA) criteria, periodontal health, and the patient's opinion were evaluated. After 14years on average, 50 restorations were available for evaluation of the CDA criteria and the patient's opinion, and 24 restorations were available for the periodontal health evaluation. Surface, color, anatomic shape, and margin integrity were considered to be in the range of excellence in 54, 78, 96, and 88%, respectively. There were no unacceptable defects. Most patients (64%) were still entirely satisfied with their restorations. Mean probing depths were significantly higher on teeth with tooth-supported Empress 2 restorations than on control teeth (p = 0.0401). No significant relationship was found between surface quality and plaque accumulation (p = 0.9450, generalized linear mixed model) or between surface quality and periodontal probing ≥ 4mm (p = 0.4184, generalized linear mixed model). The clinical quality of the Empress 2 restorations that had survived 14years on average was totally satisfactory with regard to esthetics, design, and patient's opinion. The periodontal health of all-ceramic restored teeth requires further investigation. The practitioner's choice of dental materials is based, at best, on long-term experience. With diminishing concerns about the clinical longevity of all-ceramic restorations, the grading of clinical quality based on esthetics, design, periodontal response, and patients' opinions could, nowadays, serve as a measure for the efficiency of dental ceramic.

Ten-year survival and chipping rates and clinical quality grading of zirconia-based fixed dental prostheses

To prospectively evaluate the clinical long-term outcome of 3- to 6-unit fixed dental prostheses (FDPs) made of hot isostatic pressed (HIP) zirconia frameworks, veneered with a synthetic sintering glass-ceramic. A total of 27 different restorations were cemented in 21 patients. FDPs were examined with regard to biological and technical complications/failures. Additionally, clinical quality was assessed based on (i) the California Dental Association (CDA) criteria, (ii) the patient's viewpoint according to Hickel, and (iii) periodontal parameters. Descriptive statistics were computed. The Kaplan-Meier estimator was used for the survival and chipping-free rates. Wilcoxon signed ranks test (ordinal/continuous data) or the McNemar test (binary data) was used to describe the periodontal outcome of abutment teeth versus that of the respective control teeth. After a mean observation period of 10.0 ± 2.1years, the dataset comprised 15 patients with 20 (mainly posterior) FDPs. The 10-year survival rate and 10-year chipping-free rate were 95.0% (CI 86.0-100%) and 78.8% (CI 62.2-99.7%), respectively. Evaluation based on the CDA criteria yielded satisfactory (excellent or acceptable) results for all categories. This was also confirmed by the high level of patient satisfaction. The periodontal health of tissues adjacent to the study teeth was clinically acceptable, but inferior to the ones of control teeth. FDPs made from CAD/CAM-fabricated HIP zirconia ceramic frameworks have a favorable survival rate. However, because damage to the surface texture showed a disproportionate increase after long-term usage, additional long-term studies are required. The outstanding mechanical properties of zirconia-based systems have contributed to the belief that all-ceramics are a reliable material for prosthetic restorations. However, only long-term reports (such as this one) provide more detailed information on actual clinical efficacy.

Monolithic lithium disilicate complete single crowns with feather-edge preparation design in the posterior region: A multicentric retrospective study up to 12 years.

This retrospective study evaluated the clinical success and survival of monolithic lithium disilicate single crowns in the posterior region fabricated with feather-edge margins and cemented with resin-based self-etching cement. In total, 627 pressed monolithic lithium disilicate restorations on posterior teeth (110 first premolars, 151 second premolars, 240 first molars, 121 second molars, 5 third molars) were placed in 335 patients. All teeth were prepared with feather-edge margins and restored with single crowns. The modified California Dental Association criteria were used to clinically evaluate subjects during regular maintenance recalls. The mean follow-up time was 48.17 months (SD, 27.7; range, 6 to 144). Nine crowns were replaced during the follow-up period due to bulk fracture of the material (overall 97.93% survival rate), and four teeth were extracted. No other technical or biologic failure was observed. In this retrospective evaluation, monolithic lithium disilicate crowns with feather-edge margins yielded clinical outcomes similar to those reported with other margin designs and materials. Following the same clinical protocol, crowns on second molars showed lower survival rates when compared to restorations on other teeth in the posterior region. Careful evaluation is mandatory in high-risk patients and terminal teeth. Alternative restorative materials, such as full-contour zirconia crowns, should be considered for the restoration of second molars.

Mini dental assessment: a simple screening test for non-dental staff.

The objective of this study was to develop a simple tool for the assessment of possible dental treatment needs (DTN) for non-dental professionals (Mini Dental Assessment, MDA). To keep the assessment universal, we aimed to base it on the patient's history and a simple chewing efficiency test (CET) as the dental status is a known determinant for chewing efficiency. The assessment was developed using data from 169 patients from two sites (University Hospital Giessen, St. Bonifatius Hospital Lingen, both Germany). In all patients, a dental examination was performed, the denture status was evaluated (based on the California Dental Association criteria; CDA criteria), and the DTN was determined. In addition, the time since the patient's last visit to a dentist (TLVD) and denture age (DA) were assessed. Furthermore, a CET was carried out and the comminution score was determined (CETS). In total, 108 patients required dental treatment. The mean value (±SD) was 2.9±0.9 score points for the DTN, 2.5±3.8years for the TLVD, and 10.8±8.9years for the DA. There was a significant correlation (Spearman, P<.05) between the DTN and degree of comminution (3.4±1.8). Based on the results of the statistical analysis, the intended assessment tool was developed using the variables CETS, TLVD, and DA weighed by their respective regression coefficients (10:3:1). Subsequently, the resulting MDA score (51.32±28.14) was calculated. A sensitivity/specificity analysis was conducted and a receiver operating characteristic curve was calculated (SPSS 17.0, area under curve 0.805; 95% CI 0.738-0.873). It can be concluded that the dental status of elderly patients is reflected in the outcome of the MDA. However, ongoing validation is needed. DRKS00003219.

Clinical Evaluation of 860 Anterior and Posterior Lithium Disilicate Restorations: Retrospective Study with a Mean Follow-up of 3 Years and a Maximum Observational Period of 6 Years

This study aimed to assess the clinical performance of lithium disilicate restorations supported by natural teeth or implants. Eight hundred sixty lithium disilicate adhesive restorations, including crowns on natural teeth and implant abutments, veneers, and onlays, were made in 312 patients. Parafunctional patients were included, but subjects with uncontrolled periodontitis and gingival inflammation were excluded. Veneers up to 0.5 mm thick were luted with flowable composite resin or light curing cements, while dual-curing composite systems were used with veneers up to 0.8 mm thick. Onlays up to 2 mm in thickness were luted with flowable composite resins or dual-curing composite cements. Crowns up to 1 mm in thickness were cemented with self-adhesive or dual-curing resin cements. The observational period ranged from 12 to 72 months, with a mean follow-up of 3 years. The mechanical and esthetic outcomes of the restorations were evaluated according to the modified California Dental Association (CDA) criteria. Data were analyzed with descriptive statistics. Twenty-six mechanical complications were observed: 17 porcelain chippings, 5 fractures, and 4 losses of retention. Structural drawbacks occurred mainly in posterior segments, and monolithic restorations showed the lowest number of mechanical complications. The clinical ratings of the successful restorations, both monolithic and layered, were satisfactory according to the modified CDA criteria for color match, porcelain surface, and marginal integrity. The cumulative survival rates of lithium disilicate restorations ranged from 95.46% to 100%, while cumulative success rates ranged from 95.39% to 100%. All restorations recorded very high survival and success rates. The use of lithium disilicate restorations in fixed prosthodontics proved to be effective and reliable in the short- and medium-term.

Elemental ion release from fixed restorative materials into patient saliva

The objective of this study was to quantitatively investigate the elemental ion release from the fixed gold alloy and ceramic crowns into patient saliva. Twenty patients who participated in the study were divided into two equal groups; 1) full coverage type IV gold crowns and 2) full coverage CAD-CAM-fabricated ceramic crowns. Saliva collection and clinical evaluation of marginal integrity and gingival health were performed before crowns preparation, 3 months and 6 months after crowns placement. Clinical evaluations were conducted using California Dental Association criteria. Collected saliva samples were analysed for element release using inductively coupled plasma mass spectrometer. The zinc, copper, palladium, gold and silver were released from type IV gold crowns into saliva, while the silicon and aluminium were released from ceramic crowns. A clinically significant number of subjects had increased release of zinc from baseline to three-month recall and increased silicon release from baseline to both three-month and six-month recalls. For all elements, the subjects' counts for the case of three-month recall to six-month recall were never higher than that of the case of baseline to three-month recall except for palladium. No obvious adverse effects on marginal integrity or gingival health were noticed. Significant increased releases of zinc from cast gold crowns and silicon from CAD-CAM-fabricated ceramic crowns into the saliva were evident after 3 months of clinical service.

Five-year clinical evaluation of In-Ceram crowns fabricated using GN-I (CAD/CAM) system

This study prospectively evaluated the clinical performance of computer-assisted design and computer-assisted manufacturing (CAD/CAM)-generated In-Ceram Alumina core crowns in Japanese patients for up to 5 years. A total of 101 In-Ceram crowns with aluminium copings fabricated using the GN-I system were placed in Japanese patients. The crowns were evaluated using a California Dental Association (CDA) quality assessment system at baseline and at all follow-up examinations. Gingival condition was assessed using plaque and bleeding scores. The survival of anterior and posterior crowns was analysed according to the Kaplan-Meier method. The scores of gingival condition were compared between restored crowns and contralateral teeth using a t-test. During the observation period, six crowns were lost to follow-up. Five crowns were fractured from the copings and removed, and four crowns were removed for other reasons. Chipping within the porcelain was detected in three crowns, which were then polished. The cumulative survival rates after 60 months were 96·9% for anterior crowns and 87·7% for posterior ones, and there were no significant differences between anterior and posterior crowns. According to the CDA criteria, most of the crowns were rated as satisfactory during the observation period. There were significant differences in soft tissue conditions between In-Ceram crowns and control teeth at 2- and 5-year examinations. Despite the five fractures from copings, In-Ceram Alumina crowns with copings fabricated using the CAD/CAM (GN-I system) for replacing both anterior and posterior teeth showed predictable results during a 5-year observation period.

Clinical evaluation of posterior all-ceramic FPDs (Cercon): A prospective clinical pilot study

This study prospectively evaluated the clinical performance of posterior zirconium-oxide-based all-ceramic fixed partial dentures (FPDs). Forty-two abutments of 21 Cercon FPDs were fitted in 20 patients at the Tsurumi University Dental Hospital from August 2005 to August 2006. The performance of these FPDs was evaluated using the California Dental Association (CDA) quality assessment system at baseline and at all follow-up examinations. All FPDs were examined after a mean observation period of 28.1 (+/-3.4) months. During the observation period, no fracturing of FPDs was seen. All of the FPDs examined were rated as satisfactory with regard to all factors at the follow-up examinations based on the CDA quality assessment criteria. Within the limitations of this short-term clinical study, no core framework fractures were seen. According to the CDA criteria, 100% of the FPDs were rated as satisfactory during this observation period.

Clinical evaluation of Procera AllCeram crowns in Japanese patients: results after 5 years

Procera AllCeram crowns were prospectively evaluated clinically in both anterior and posterior regions in Japanese. One-hundred and one crowns were fabricated for 57 patients at the Tsurumi University Dental Hospital from August 2001 to October 2002 and evaluated according to the California Dental Association (CDA) quality evaluation system at baseline and annually at all follow-up examinations for 5 years. The plaque index (PI) and gingival index (GI) were recorded, and chipping and fracture were checked at the same time as well. A total of 75 Procera AllCeram crowns were evaluated, and the cumulative survival rate was 90.2% over the 5-year clinical trial. Six crowns experienced fractures within the veneering porcelain and from aluminium oxide coping, all of which occurred on the premolar and molar regions, and they had to be removed. Small chipping was observed on three crowns. According to the CDA criteria, 98% of Procera AllCeram crowns were rated as satisfactory, and PI and GI were comparable to those of control teeth during the observation period.

Effect of the Quality of Removable Prostheses on Patient Satisfaction

The objective of this study was to evaluate patient satisfaction with removable prostheses and its relationship with denture quality. Sixty-seven patients who received 119 new removable prostheses over a period of one year at the College of Dentistry, King Saud University, were recalled for an interview with regard to their satisfaction with their dentures and a clinical examination. Prosthetic quality was determined using the California Dental Association criteria. Results showed 75% and 66% of upper and lower dentures, respectively, were reported by patients as satisfactory. Of all the upper prostheses rated as being of acceptable quality, 94% were also reported by patients as satisfactory, but of those of unacceptable quality, only 52% were reported by patients as unsatisfactory. The corresponding figures for lower dentures were 91% and 71%, respectively. No significant associations were found between patient satisfaction and age, or denture experience. Although acceptable quality of removable prostheses usually resulted in patient satisfaction, the finding that some patients were satisfied with their prostheses despite unacceptable quality suggests other factors besides quality affect outcomes. Patient satisfaction with removable dentures cannot be fully predicted from only the quality standards of those dentures.

Two-year clinical performance of two one-step self-etching adhesives in the restoration of cervical lesions

The aim of the study was to evaluate the clinical performance of two different one-step self-etching adhesives (Hybrid Bond/Sun Medical, Xeno III/Dentsply) in adhesive cervical resin composite restorations. In accordance with a split-mouth study design, 50 patients (57.3+/-13.5) received at least one pair of restorations. In each of two comparable cervical cavities, either the adhesive systems Hybrid Bond or Xeno III was used with the resin composite Filtek Supreme (3M ESPE). After 6, 12 and 24 months, the restorations were scored according to the Ryge and California Dental Association criteria. After 2 years, the resulting scores (percent) of the Ryge evaluation for the groups Hybrid Bond/ Filtek Supreme and Xeno III/ Filtek Supreme were marginal integrity, Alpha (92/78), Bravo (8/2), Charlie (0/0) and Delta (0/10); anatomic form, Alpha (92/82), Bravo (8/8) and Charlie (0/10); secondary caries, Alpha (100/100) and Bravo (0/0); marginal discoloration, Alpha (80/84), Bravo (20/12), Charlie (0/0) and not available (0/4); color match, Oscar (39/47), Alpha (51/45), Bravo (10/4), Charlie (0/0) and not available (0/4); surface, Romeo (78/69), Sierra (22/22), Tango (0/0) and Victor (0/10); tooth vitality, Alpha (98/94), Bravo (2/6); and integrity of tooth, alpha 1 (96/96) and alpha 2 (4/4). After 2 years, all Hybrid Bond restorations were retained and showed clinically acceptable results, while five Xeno III restorations were lost in part or in toto. For marginal integrity, anatomic form and surface, significant differences (p<0.05) were found but did not prove statistically significant after Bonferroni adjustment.

Clinical Evaluation of In-Ceram Crowns Fabricated Using GN-I System: Preliminary Results after 24-39 Months of Use

Purpose: This study prospectively evaluated the clinical performance of CAD/CAM-generated In-Ceram alumina core crowns.Methods: The GN-I system was used to fabricate the 101 In-Ceram crowns with aluminum copings placed in 39 patients. Using a modified quality assessment system developed by the California Dental Association (CDA), the crowns were evaluated at baseline and at all follow-up examinations.Results: The mean service time of the crowns was 28.7 months. Six crowns fractured or were removed; a maxillary first molar crown and a mandibular second premolar crown fractured after 17 months and 22 months, respectively. Others were removed due to esthetic complications, endodontic therapy, root fracture, and so on. A small chip was detected in a mandibular canine crown after functioning for 6 months. After 39 months, the cumulative survival rate of the crowns was 93.9%. According to the modified CDA criteria, most crowns were rated as “satisfactory” during the observation period.Conclusion: Despite the 2 fractures, In-Ceram Alumina crowns with copings fabricated using CAD/CAM (GN-I system) showed excellent results during the observation period.

Prospective Clinical Study of Procera AllCeram Crowns:2-3 year Preliminary Results

Purpose: The Procera system was introduced in Japan in December 2000, however, there have been few clinical evaluations of the Procera AllCeram crowns. The purpose of this study was to prospectively evaluate the clinical performance of Procera AllCeram crowns.Methods: One hundred and one Procera AllCeram crowns were placed in patients' oral cavities at the Tsurumi University Dental Hospital from July 2001 to October 2002. The performance of these crowns was evaluated using the California Dental Association (CDA) quality assessment system at baseline and at all followup examinations.Results: A total of 101, 97 and 67 crowns were examined at 1, 2 and 3 years after their fixation, respectively. During the three-year period, six crowns were removed because of fracture of the copings, fracture of the porcelain veneer, root fracture, or esthetic problems. Small incisal chips were detected in three crowns. All of the crowns examined were rated as satisfactory according to the CDA quality assessment criteria, except for the surface and anatomic form.Conclusion: During the 3-year follow-up period, six crowns were removed, yielding a cumulative survival rate of 93.2%. All (100%) of the Procera AllCeram crowns were rated as satisfactory in terms of the clinical performance according to the CDA criteria, and to be useful for both anterior and posterior teeth. However, the observation period was short, and evaluation over a longer period of time is necessary for a more precise evaluation of these crowns.

Secondary caries in crowned teeth: Correlation of clinical and radiographic findings

Statement of Problem. The diagnostic value of radiographs for interproximal caries detection on nonrestored teeth is well investigated. However, little is known about the use of radiographs in the diagnosis of secondary caries localized at crown margins. Purpose. The aim of this study was to correlate clinical findings with regard to secondary caries with the findings of a radiographic evaluation. Material and Methods. One hundred randomly selected patients who underwent restorations with fixed prostheses and were exhibiting at least one secondary carious lesion were included in the study. A total of 820 restorations (test group, 730 interproximal surfaces of 365 single crowns and 910 interproximal surfaces of 455 fixed partial denture retainer crowns) and 1024 interproximal surfaces of 512 nonrestored teeth (control group) were investigated clinically, with the use of modified California Dental Association criteria, and radiographically for interproximal carious lesions. The extension of the lesions was rated to be initial (with no cavitation), early (with cavitation limited to orthodentin), or deep (with cavitation). The data were statistically analyzed for normal distribution, and the frequency of the findings was calculated in absolute numbers and as a percentage. Statistically significant differences were determined by use of the χ2 test (P<.05). A linear regression model was applied for the correlation between the percentage of secondary caries and the duration of the crowns in situ. Results. Secondary caries was diagnosed clinically in 11.2% of 1640 interproximal surfaces but only in 8.3% radiographically. In contrast, the frequency of interproximal carious lesions diagnosed clinically in nonrestored teeth increased with the use of radiographs from 3.3% to 4.1%. Conclusion. Within the limits of this study, the results confirm that radiographs improve the diagnostic sensitivity for interproximal caries in nonrestored teeth. However, for the diagnosis of secondary caries in crowned teeth, the clinical examination is more reliable than the radiographic evaluation. (J Prosthet Dent 2002;88:314-9.)

Cerana--a new method for the restoration of teeth with prefabricated ceramic inlays.

Cerana are all-ceramic, prefabricated inlays which replace enamel and are produced in a lucite-reinforced glass ceramic. To evaluate the clinical quality of Cerana inlay therapy, 38 patients with a total of 60 inlays were examined in a retrospective cross-sectional study. The inlays were primarily of Class I type, but even Class II tunnel preparations and Class V were examined. The median age of the inlays was 1.5 years. A modified form of the California Dental Association criteria was used in the evaluation. The results show that all inlays were of excellent or acceptable character in terms of marginal fit, colour and surface roughness. None of the patients reported any post-operative symptoms of pain. One restoration had secondary caries and a fractured marginal ridge. One restoration with poor anatomical form caused by a fractured filling and one restoration with deep marginal discolouration were discovered. Although the follow-up time was short, the results show that Cerana can be considered an interesting alternative to other tooth-coloured materials on the market.