Modified US Public Health Service Research Articles

Clinical evaluation of the bulk fill composite QuiXfil in molar class I and II cavities: 10-year results of a RCT

ObjectiveThe objective of this RCT was to compare the 10-year clinical performance of QuiXfil with that of Tetric Ceram in posterior single- or multi-surface cavities. Methods46 QuiXfil (Xeno III) and 50 Tetric Ceram (Syntac classic) composite restorations were placed in 14 stress bearing class I and 82 class II cavities in first or second molars. Clinical evaluation was performed at baseline and after up to 10 years by using modified US Public Health Service criteria. At the last recall period, 26 QuiXfil and 30 Tetric Ceram restorations in 11 stress bearing class I and 45 class II cavities, were assessed. ResultsTen failed restorations were observed during the follow-up period, four Tetric Ceram restorations failed due to secondary caries (2), tooth fracture (1) and bulk fracture combined with secondary caries (1) whereas six QuiXfil restorations failed due to secondary caries (1), tooth fracture (2), secondary caries combined with restoration fracture (1), restoration fracture (1) and postoperative sensitivity (1). Fisher’s exact test yielded no significant difference between both materials (p=0.487). SignificanceBoth materials, bulk fill QuiXfil restorations and Tetric Ceram restorations, showed highly clinical effectiveness during the 10-year follow-up.

A 3-year clinical evaluation of endodontically treated posterior teeth restored with two different materials using the CEREC AC chair-side system

Statement of problemThe introduction of polymer-infiltrated ceramic network (PICN) materials may provide more options for dentists in restoring short clinical crowns and extensively damaged posterior teeth, but clinical data for their performance are lacking. PurposeThe purpose of this clinical study was to compare the 3-year performance and survival rates of PICN material with those of conservative ceramic onlay restorations for endodontically treated posterior teeth using the CEREC AC chair-side system. Material and methodsA total of 101 onlay restorations of endodontically treated posterior teeth using the CEREC AC chair-side system were provided in 93 participants. The 101 teeth were divided into 2 groups: Vita Enamic group and Vitablocs Mark II group. Using the modified US Public Health Service quality evaluation system, 2 calibrated evaluators examined the performance of the onlay restorations over 3 years. The Kaplan-Meier method was adopted to analyze the survival rate of restorations (α=.05). The log rank test was used to compare the survival rates of the 2 groups. The Fisher exact test was performed to detect differences in the success rates for extensively damaged teeth and short clinical crown restorations between the 2 groups. The Silness and Löe gingival index was also recorded. ResultsThe restoration survival rates in the 2 groups were 97.0% (Vita Enamic) and 90.7% (Vitablocs Mark II) (P>.05). Five failures were recorded (4.95%). These failures were caused by restoration debonding (60%), ceramic fractures (20%), and tooth fractures (20%). There were no significant differences between the success rates of restoring extensively damaged teeth and short clinical crowns between the 2 groups (P>.05). The periodontal condition of 25% of participants was improved 3 years after the onlay restorations. ConclusionsOnlay restorations of endodontically treated posterior teeth with Vita Enamic using the CEREC AC chair-side system are clinically promising prosthodontic alternatives, with a survival rate of 97.0% after 3 years. More research is needed to verify the results of this study.

CAD/CAM-fabricated ceramic implant-supported single crowns made from lithium disilicate: Final results of a 5-year prospective cohort study.

All-ceramic bilayer systems suffer from technique-sensitivity, resulting in increased technical complication rates. This might be overcome by monolithic reconstructions, facilitating digital workflows. To evaluate the clinical and patient-reported outcome of CAD/CAM-fabricated implant-supported single crowns (ISCs) made of lithium disilicate (LS2 ) cemented on ceramic implants 5 years after implant installation. Twenty-four patients were included in the study. All participants received a one-piece ceramic implant in anterior (4 incisors) and posterior regions (10 premolars, 10 molars). LS2 crowns were computer-aided designed (CAD), manufactured (CAM) and adhesively luted onto the implants. Follow-ups were performed yearly up to 60 months after implant installation. The survival/success rates of the restorations were calculated according to modified US Public Health Service criteria as follows: Clinically relevant defects that could be repaired intraorally were accepted for survival, whereas small-area chippings, roughness (ø < 2 mm), slightly soundable marginal gaps, minimal undercontours/overcontours, and tolerable color deviations were accepted for success. Kaplan-Meier plots were used for the success/survival analyses. Furthermore, patient-reported outcome measures (PROMs) were assessed by applying visual analog scales (VAS). Linear (PROMs) and logistic (USPHS criteria) mixed models were fitted to evaluate time effects on response variables. Twenty-two ISCs could be evaluated 55.2 ± 4.2 months after prosthetic delivery. Two patients were reported as drop-outs (1 died, 1 moved abroad). No failures were observed, resulting in 100% survival. At two ISCs, a major-roughness had to be treated. This resulted in a Kaplan-Meier success estimate of 91.7% (95%CI: 70.6%-97.9%). Compared with pretreatment, all surveys at prosthetic delivery except for self-esteem (P = .375) showed significantly improved VAS scores. No decrease in satisfaction could be observed over time until the end of follow-up (P ≥ .056). Concerning survival/success rates and PROMs, the evaluated crown-implant system showed favorable mid-term results. To date, there are no comparable data available for implant-supported ISCs made of LS2 .

The Survival of Class V Composite Restorations and Analysis of Marginal Discoloration.

The aims of this retrospective clinical study were to analyze the longevity of class V composite restorations and compare the results obtained from clinical and laboratory evaluation of marginal discoloration. A total of 186 restorations were evaluated with modified US Public Health Service criteria. Longevity and associated variables were analyzed with the Kaplan-Meier method and a Cox proportional hazard model. Restorations with marginal discoloration were additionally evaluated using digital photographs and epoxy resin replicas under a stereomicroscope. The mean survival time was 15.0 years, with five- and 10-year survival rates of 95.5% and 83.1%, respectively. Z250 had a higher risk of failure (hazard ratio=7.01, 95% confidence interval=2.07-23.72) than Z100. In addition, the presence of occlusal wear facets and bleeding on probing were associated with an increased risk of failure of the restorations. However, the use of an adhesive system (Scotchbond Multi-Purpose or Clearfil SE Bond) did not affect the longevity of the restorations. The results of laboratory evaluation were significantly different from clinical evaluation (p<0.001, McNemar test). Among 55 restorations rated as Bravo in the clinical evaluation, 24 restorations (43.6%) were determined to have penetrating discoloration on laboratory evaluation. When evaluating aged composite restorations, surface refurbishment and the use of a microscope are recommended, which will be helpful in determining the need for timely repair or replacement.

Chair-side generated posterior monolithic lithium disilicate crowns: clinical survival after 6years.

The objective of this prospective clinical study was to evaluate the clinical performance of chair-side generated monolithic lithium disilicate crowns after 72months. Forty-one posterior full contour crowns made of lithium disilicate ceramic were inserted in 34 patients with a chair-side CAD/CAM technique. One crown per patient was randomly selected for evaluation at baseline, 6, 12, 24, 36, 48, 60 and 72months according to the modified US Public Health Service criteria. After a mean examination time of 73.2months (SD±1.7months), 25 crowns were available for re-examination. Within the observation period, three failures occurred due to one crown fracture after 2.9years, an abutment fracture after 6.0years, and one severe endodontic problem after 6.1years. One lithium disilicate crown showed a loss of retention after 2years but could be reinserted. There were two events of caries below the crown margin, one after 24 and another one after 48months. Both teeth received cervical adhesive composite fillings. Two abutment teeth changed their sensibility perception from positive to negative within the first 13months. The failure-free rate was 87.6%, and the complication-free rate was 70.1% after 6years according to the Kaplan-Meier analysis. Due to the fact that there was only one severe technical complication and the severe biological complications were in a normal range, the clinical performance of monolithic lithium disilicate crowns in the posterior region was completely satisfying. The chair-side application of monolithic lithium disilicate crowns can be recommended.

A Prospective Six-Year Clinical Study Evaluating Reinforced Glass Ionomer Cements with Resin Coating on Posterior Teeth: Quo Vadis?

The aim of this study was to evaluate the long-term clinical performance of two encapsulated glass ionomer cements (GICs) (EquiaFil and Riva SC) covered with two different coatings (Equia Coat and Fuji Varnish) over six years using modified US Public Health Service (USPHS) criteria. Fifty-four patients having class I and II restorations/caries were included in the study. A total of 256 restorations were made with EquiaFil and Riva SC. Equia Coat or Fuji Varnish was used randomly on the surface of the restorations. After cavity preparations, the teeth were randomly restored with one GIC and coated with Equia Coat or Fuji Varnish. The restorations were evaluated at baseline; six, 12, and 18 months; and six years after placement using modified USPHS criteria. Two evaluators checked color match, marginal discoloration, marginal adaptation, caries formation, anatomical form, postoperative sensitivity, and retention rate, and photographs were taken at each recall. The results were evaluated with Pearson chi-square and Mann-Whitney U-test (p<0.05). Thirty-seven patients were evaluated. There was a significant difference between EquiaFil and Riva SC regarding retention rate and color match after six years (p=0.033 and 0.046). When comparing baseline to six years, the overall success of EquiaFil was better than Riva SC, having significant problems regarding retention rate and anatomical form (p=0.016 and 0.031). Class II cavities were significantly worse in marginal adaptation, anatomical form, and retention rate in the Riva SC groups (p=0.033, 0.015, and 0.007) but not in the EquiaFil groups. The combination of the coatings had no effect on the overall success of the materials. The EquiaFil system was more successful than Riva SC regarding color match, marginal adaptation, anatomic form, and retention rate after a six-year clinical evaluation period.

Evaluation of Biodentine in the Restoration of Root Caries: A Randomized Controlled Trial.

There is no "gold-standard" material for the operative management of root caries. The aim of this study was to determine if the clinical performance of Biodentine would be acceptable for the restoration of root caries in older adults. A randomized controlled clinical trial was conducted comparing a calcium silicate cement (Biodentine), a high-viscosity glass ionomer cement (Fuji IX GP Extra), and a resin-modified glass ionomer cement (Fuji II LC). Of the 334 volunteers assessed for eligibility, 249 were excluded. A total of 303 lesions in 85 participants were randomized, with 151 lesions allocated to receive Biodentine, 77 to Fuji IX GP Extra, and 77 to Fuji II LC. Patients were reviewed by a calibrated dentist who was not involved in restoration placement and who was blinded to material allocation. Restorations were assessed according to a modified US Public Health Service criteria. The cumulative survival percentages after 6 mo and 1 y were 58.6% and 47.2% in the Biodentine group, 89.6% and 83.8% in the Fuji IX GP Extra group, and 89.5% and 84.9% in the Fuji II LC group, respectively. There were statistically significant differences ( χ2 test, P < 0.001) in restoration failure rates between restoration groups. There was no difference between Fuji IX GP Extra and Fuji II LC, but differences ( P < 0.001) were shown between the Fuji II GP Extra group and the Biodentine group and also between the Fuji II LC group and the Biodentine group at both time points. Based on the results of this study, Biodentine cannot be recommended for the operative management of root caries. Fuji IX GP Extra and Fuji II LC displayed similar success rates, and high-viscosity glass ionomer cement and resin-modified glass ionomer cement continue to be the best available option for the restoration of root caries ( ClinicalTrials.gov NCT01866059). Knowledge Transfer Statement: The results of this study can assist dental practitioners when selecting a restorative material for the operative management of root caries. This randomized controlled trial compared the 1-y clinical performance of a calcium silicate-based material to that of a high-viscosity glass ionomer cement and a resin-modified glass ionomer cement in the operative management of root caries. The study concluded that high-viscosity glass ionomer cement and resin-modified glass ionomer cement continue to be the best available option to dental practitioners when restoring the root surface.

Clinical evaluation of two materials in the restoration of abfraction lesions

Aim: To evaluate the clinical performance of a composite resin (CR) and a resin-modified glass-ionomer cement (RMGIC) for the treatment of abfraction lesions. Methods: Thirty patients with abfraction lesions in at least two premolar teeth were selected and invited to participate in this study. All restorations were made within the same clinical time frame. One tooth was restored with CR Z100TM (3M, St. Paul, MN, USA), and the other was restored with RMGIC VitremerTM (3M). The restorations were assessed immediately and 1, 6 and 12 months after the restoration, using modified US Public Health Service (USPHS) criteria: marginal integrity, marginal discoloration, wear, retention, secondary caries and hypersensitivity. The statistical analysis was based on Friedman ANOVA test and Mann-Whitney test, considering p<0.05 for statistical significance. Results: Both materials demonstrated satisfactory clinical performance after one year. In the individual analysis of each material, there was a significant difference (p<0.05) in the criteria marginal integrity and wear, for both CR and RMGIC. RMGIC exhibited more damage one year after the restoration. Comparing both materials, it was found a significant difference only for marginal discoloration, while the RMGIC restorations showed the worst prognosis after a year of evaluation. There was no significant difference in the number of retentions, caries or hypersensitivity between CR and RMGIC. Conclusions: It was concluded that CR exhibited the best clinical performance according to the cost-effectiveness and evaluation criteria used in this study.

Two-year clinical performance of dimethacrylatebased composite restorations repaired with a silorane-based composite.

To investigate the clinical performance of a silorane-based composite resin used for repairing dimethacrylate- based composite restorations. One operator repaired defective dimethacrylate-based resin restorations that were randomly assigned to one of two treatment groups: control (n=50), repaired with Adper SE Plus and Filtek P60 Posterior Restorative (3M ESPE); or test (n=50), repaired with P90 System Adhesive Self-Etch Primer and Bond and Filtek P90 Low Shrink Posterior Restorative (3M ESPE). After 1 week, restorations were finished and polished. Two calibrated examiners (weighted Kappa≥0.78) evaluated the repaired restorations, blindly and independently, at baseline, after 6 months, 1 and 2 years. The parameters examined were marginal adaptation, anatomic form, surface roughness, marginal discoloration, postoperative sensitivity, and secondary caries. The restorations were classified as Alfa, Bravo, or Charlie, according to modified US Public Health Service criteria. Variation in the levels of clinical parameters over time was evaluated by Friedman's ANOVA (α=0.05). The Mann-Whitney test assessed the differences between the materials for all clinical criteria at baseline, 6-month, 1- and 2-year recalls (α=0.05). The Wilcoxon test compared each composite resin for all clinical criteria at the same recalls (α=0.05). After two years, 79 repaired restorations were re-examined. No statistically significant differences were found between the materials at baseline or at the 2-year recall (p>0.05). Comparing baseline and 2-year recall, there was a statistically significant difference for marginal discoloration (p=0.029) in silorane-based composite restorations. After two years, the clinical performance of the silorane-based composite was similar to that of the dimethacrylate-based composite when used to make repairs.

Four-year randomized clinical trial to evaluate the clinical performance of a glass ionomer restorative system.

The aim of this study was to evaluate the clinical performance of a glass ionomer restorative system compared with a microfilled hybrid posterior composite in a four-year randomized clinical trial. A total of 140 (80 Class 1 and 60 Class 2) lesions in 59 patients were either restored with a glass ionomer restorative system (Equia, GC, Tokyo, Japan), which was a combination of a packable glass ionomer (Equia Fil, GC) and a self-adhesive nanofilled coating (Equia Coat, GC), or with a microfilled hybrid composite (Gradia Direct Posterior, GC) in combination with a self-etch adhesive (G-Bond, GC) by two experienced operators according to the manufacturer's instructions. Two independent examiners evaluated the restorations at baseline and at one, two, three, and four years postrestoration according to the modified US Public Health Service criteria. Polyvinyl siloxane impression negative replicas at each recall were observed under scanning electron microscopy (SEM) to evaluate surface characteristics. The statistical analyses were carried out with McNemar, Pearson Chi-square, and Cochran Q-tests (p<0.05). After four years, 126 (76 Class 1 and 50 Class 2) restorations were evaluated in 52 patients, with a recall rate of 88.1%. None of the restorations showed trends to downgrade in anatomical form, secondary caries, surface texture, postoperative sensitivity, and color match (p>0.05). Significant differences in marginal adaptation and discoloration were found at four years compared to baseline for both restorative materials for Class 1 and Class 2 restorations (p<0.05). Only one Class 2 Equia restoration was missing at three years (3.9%), and another one was missing at four years (7.7%) (p>0.05). SEM evaluations were in accordance with the clinical findings. The use of both materials for the restoration of posterior teeth exhibited a similar and clinically successful performance after four years.

Seven-year clinical performance of resin composite versus resin-modified glass ionomer restorations in noncarious cervical lesions.

The purpose of this study was to comparatively assess the seven-year clinical performance of a one-bottle etch-and-rinse adhesive with resin composite (RC) and resin-modified glass ionomer (RMGI) restorations in noncarious cervical lesions. One operator placed 70 restorations (35 restorations in each group) in 30 patients under rubber dam isolation without mechanical preparation. The restorations were directly assessed by two independent examiners, using modified US Public Health Service criteria at baseline and 6, 12, 24, 60, and 84 months. The obtained data were tabulated and statistically analyzed using the Fisher and McNemar tests. A difference was significant if p<0.05. Twenty patients were available for recall after seven years (66.6%), and 25 RC and 26 RMGI restorations out of 70 restorations were evaluated. Excellent agreement was registered for all criteria between examiners (κ≥0.85). Alfa and bravo scores were classified as clinically acceptable. The McNemar test detected significant differences within RC restorations between baseline and seven-year evaluations for anatomic form, marginal integrity, and retention (p<0.05). For RMGI restorations, a significant difference was identified for marginal integrity (p<0.05). As to material comparison, the Fisher exact showed a better retention performance for RMGI restorations than for RC restorations (p<0.05). Twelve composite restorations were dislodged (52.0% retention) and three ionomer restorations were lost (88.5% retention). The cumulative success rate for RC and RMGI was 30% and 58.1%, respectively. After seven years of service, the clinical performance of RMGI restorations was superior to that of the adhesive system/resin composite restorations in this study.

The survival of indirect composite resin onlays for the restoration of root filled teeth: a retrospective medium‐term study

To investigate the outcomes of root filled posterior teeth restored with indirect composite resin onlays using tooth and restoration survival as well as the quality of restoration as outcome measures. All patients were treated by the same clinician with indirect composite onlays for the restoration of root filled posterior teeth between January 2008 and February 2010 in a single clinic setting. Primary root canal treatment was performed and onlays fabricated with the indirect method using indirect composite resin. Patients were seen every 4-6months for maintenance visits according to standard clinic protocols and each patient's individualized maintenance schedule. Tooth and restoration survival were calculated, and the onlays were evaluated in accordance with the modified US Public Health Service (USPHS) criteria. Thirty-one premolars and one hundred and fifty-eight molars (n=189) of 153 patients were included. The observation period ranged from 24 to 52months with a median follow-up time of 37months. Tooth survival was found to be 100%, whilst the restoration survival was 96.8% and the functional restoration survival 98.9% at the end of the follow-up period. According to modified USPHS criteria, the A rating had a range of 83.1-100% for all evaluation criteria. Onlay restorations fabricated with indirect resin can be a viable option for the restoration of root filled teeth.

Three-year randomized clinical evaluation of a low-shrinkage silorane-based resin composite in non-carious cervical lesions

The clinical suitability of low-shrinkage resin composites for class V cavities has not been investigated in vivo. The purpose of this double-blind randomized clinical trial was to compare the clinical performances of low-shrinkage resin composite Filtek silorane and nanoceramic resin composite Ceram X mono in non-carious cervical lesions (NCCLs) over 36 months. Two calibrated operators restored 144 NCCLs in 24 patients by using Filtek silorane with silorane system adhesive (FS/SSA) and Ceram X mono with Clearfil SE (CXM/CSE) or XP bond (CXM/XPB). Then, two blinded, calibrated evaluators assessed the restorations at the baseline and 6, 12, 24, and 36 months thereafter by using the modified US Public Health Service criteria. Data were analyzed with the Freidman and Wilcoxon signed-rank tests at a significance level of 5 % (P < 0.05). No restoration was associated with postoperative sensitivity or secondary caries. Further, no group showed significant changes until 12 months. The retention rates of the FS/SSA (97.5 %), CXM/CSE (97.5 %), and CXM/XPB (92.31 %) restorations did not differ significantly (P > 0.05). Six (4 CXM/XPB, 1 FS/SSA, and 1 CXM/CSE) of the 121 restorations evaluated at 36 months were completely lost. However, no significant intergroup differences were observed in the other evaluation criteria. The 3-year clinical performances of the restorative materials in NCCLs were not significantly different. Filtek silorane is suitable for restoring NCCLs.

Clinical Performance of Ormocer, Nanofilled, and Nanoceramic Resin Composites in Class I and Class II Restorations: A Three-year Evaluation

This prospective long-term clinical trial evaluated and compared the three-year clinical performance of an ormocer, a nanofilled, and a nanoceramic resin composite with that of a microhybrid composite placed in Class I and Class II cavities. Forty patients, each with four Class I and II restorations under occlusion, were enrolled in this study. A total of 160 restorations were placed, 25% for each material, as follows: an ormocer-based composite, Admira; a nanofilled resin composite, Filtek Supreme XT; a nanoceramic resin composite, Ceram X; and a microhybrid resin composite, Tetric Ceram. A single operator placed all restorations according to the manufacturers' instructions. Immediately after placement the restorations were finished/polished. Clinical evaluation was performed at baseline and at yearly intervals after placement by two other independent examiners using modified US Public Health Service (USPHS) criteria. The changes in the USPHS parameters during the three-year period were analyzed with the Friedman test. Comparison of the baseline scores with those at the recall visits was made using the Wilcoxon signed rank test. The level of significance was set at p < 0.05. All materials showed only minor changes, and no differences were detected between their performance at baseline and after three years. Only two ormocer, one nanofilled, and one microhybrid restorations in molars failed because of loss of retention. Regarding the clinical performance, there were no statistically significant differences among the materials used (p>0.05). The ormocer, nanofilled, and nanoceramic composites provided acceptable clinical performance over a three-year period.

Longevity of Direct Restorations in Stress-Bearing Posterior Cavities: A Retrospective Study

The aims of this retrospective clinical study were to compare the longevities of direct posterior amalgam restorations (AMs) and resin composite restorations (RCs) that were subjected to occlusal stresses and to investigate variables predictive of their outcome. A total of 269 AMs and RCs filled in Class I and II cavities of posterior teeth were evaluated with Kaplan-Meier survival estimator and multivariate Cox proportional hazard model. Seventy-one retreated restorations were reviewed from dental records. The other 198 restorations still in use were evaluated according to modified US Public Health Service (USPHS) criteria by two investigators. The longevity of RCs was significantly lower than that of AMs (AM = 8.7 years and RC = 5.0 years, p<0.05), especially in molars. The prognostic variables, such as age, restorative material, tooth type, operator group, diagnosis, cavity classification, and gender, affected the longevity of the restorations (multivariate Cox regression analysis, p<0.05). However, among the restorations working in oral cavities, their clinical performance evaluated with modified USPHS criteria showed no statistical difference between both restoratives. In contrast to the short longevity of RCs relative to AMs, the clinical performance of RCs working in oral cavities was observed to be not different from that of AMs. This suggests that once a RC starts to fail, it happens in a rapid progression. As posterior esthetic restorations, RCs must be observed carefully with periodic follow-ups for early detection and timely repair of failures.

Nanohybrid vs. fine hybrid composite in extended class II cavities: 8-year results

In a controlled prospective split-mouth study, clinical behavior of two different resin composites in extended class II cavities was observed over 8 years. Thirty patients received 68 direct resin composite restorations (Solobond M/Grandio, Voco--n = 36; Syntac/Tetric Ceram, Ivoclar Vivadent--n = 32) by one dentist in a private practice. Thirty-five percent of cavities revealed no enamel at the bottom of the proximal box, 48% of cavities provided <0.5 mm remaining proximal enamel width. Restorations were examined according to modified US Public Health Service criteria at baseline, after 6 months, and 1, 2, 4, 6, and 8 years. All patients attended the 8-year recall. The overall success rate of all restorations was 98.5% (Kaplan-Meier survival algorithm). One Grandio restoration was lost due to bulk fracture. One Tetric Ceram restoration suffered drop out due to cusp fracture having been not related to the restoration itself. Neither restorative materials nor localization of the restorations had a significant influence on any criterion except color (darker for Grandio). Restorations in molars performed inferior compared with premolars regarding marginal integrity (4 years), restoration integrity (6, 12, 24, 48, and 96 months), and tooth integrity (12, 48, 72, and 96 months). Irrespective of the resin composite used, significant changes over time were found for all criteria evaluated in clinical examinations. Beyond the 4-year recall, marginal staining increased. Both phenomena were found earlier in molars compared with premolars. Tooth integrity significantly deteriorated because of increasing enamel cracks and chippings over time. Both materials performed satisfactorily over the 8-year observation period. Due to the extension of the restorations, wear was clearly visible after 8 years of clinical service. Hybrid and nanohybrid resin composites show an acceptable clinical performance after 8 years of service.

A prospective cohort study on cast-metal slot-retained resin-bonded fixed dental prostheses in single missing first molar cases: results after up to 7.5 years.

To evaluate under controlled clinical conditions the outcomes of cast-metal slot-retained resin-bonded fixed dental prostheses (RBFDPs) in which resin composite interlocked the restoration retainers in place after cementation in cases with single missing first molars, and to collect survival data on this esthetic RBFDP design combined with an economical metal fit-surface treatment method and resin luting system. Forty-one tub-shaped inlay-retained RBFDPs were clinically observed for up to 7.7 years in 35 recipients of both genders between 18 and 52 years of age. Clinical examinations were performed at baseline and 6 and 12 months after restoration placement, and thereafter at regular 1-year intervals. Modified US Public Health Service (USPHS) parameters, sulcus bleeding index, Silness-Löe plaque index, pocket depths, tooth mobility, pulp vitality, and periapical radiographs regarding the abutment teeth were assessed at these follow-up appointments. The Kaplan-Meier survival estimation method was performed to detect the overall and functional survival rates and mean survival times of the RBFDPs at the end of the study. The Breslow (Generalized Wilcoxon) test was used to evaluate the influence of restoration location and age and gender of the patient regarding the overall survival probability at the end of the follow-up (α = 0.05). At the end of the study, 34 RBFDPs (83%) were still functioning with a mean follow-up of 6.3 years. According to the Kaplan-Meier survival curve, the overall and functional survival probabilities were calculated as 76% and 83%, with mean survival times of 6.8 years and 7.2 years, respectively. All clinical parameters monitored throughout the follow-up period predominantly revealed clinically acceptable results. Breslow test statistics presented nonsignificant differences with better results for the RBFDPs placed in the mandible of female recipients younger than 30 years of age. The most common failure noted with the RBFDPs was fracture of the occlusal veneering composite restoration over the retainer of a single abutment, leading to a predisposition of the restoration to partial debonding. Within the limitations of this prospective cohort study, it can be concluded that cast-metal slot-retained RBFDPs utilizing the interlocking mechanism of a resin composite to obtain additional retention from the abutment cavities show acceptable clinical success rates, and can be considered a minimally invasive, economical, and time-saving treatment alternative for the prosthetic rehabilitation of single missing first molars.

Clinical Evaluation of Self-etch and Total-etch Adhesive Systems in Noncarious Cervical Lesions: A Two-year Report

The purpose of this study was to compare the clinical performance of two self-etch dental adhesives with Single Bond Plus, a traditional one-bottle total-etch dental adhesive, for the restoration of noncarious cervical lesions. A total of 156 restorations were placed in noncarious cervical lesions with a minimum depth of 1.5 mm. Patients had no chronic periodontal disease and had normal salivary function. Each patient received restorations on three teeth, each bonded with either Adper Single Bond Plus, Adper Easy Bond, or Adper Scotchbond SE dental adhesive. All lesions were restored with Filtek Supreme Plus composite resin. All teeth were isolated with a rubber dam, received a short enamel bevel, and were cleaned with flour of pumice. The adhesives and resin composite were applied following the manufacturers' instructions. Restorations were clinically evaluated at baseline, six months, one year, and two years using modified US Public Health Service criteria. Two-year retention was recorded as 97.3%, 90.5%, and 95.2%, for Single Bond Plus, Scotchbond SE, and Easy Bond, respectively. Statistical analysis did not show a significant difference (p>0.05) in clinical performance between any of the three adhesives after a period of two years.

Chair-side generated posterior lithium disilicate crowns after 4 years

The objective of this prospective clinical study was to evaluate the performance of chair-side generated crowns after 48 months. Forty-one posterior full contour crowns made of a machinable lithium disilicate ceramic (e.max CAD LT) were inserted in 34 patients applying a chair-side CAD/CAM technique. One crown per patient was randomly selected for evaluation at baseline, after 6, 12, 24, 36, and 48 months according to modified US Public Health Service criteria. After a mean observation time of 51 months (min, 48 months; max, 56 months; SD ± 2.3 months), 29 crowns were available for re-examination. Within the observation period, one failure occurred due to a crown fracture after 2.8 years. Four abutment teeth revealed signs of biological complications: Two abutment changed sensibility perception from positive to negative within the first 13 month. Two abutment teeth showed secondary caries below the crown margin, one after the 24, and another after the 48 month recall. Both abutments received cervical adhesive composite fillings. The failure-free rate was 96.3 % after 4 years according to Kaplan-Meier (CI: upper bound, 4.4 years; lower bound, 4.7 years). Due to the fact that the secondary caries was not caused as a result of an inaccuracy of the crown margins and the endodontic complications were in a normal range, the clinical performance of the crowns was completely satisfying. The chair-side application of lithium disilicate crowns can be recommended.

Noncarious Cervical Lesions Restored with Three Different Tooth-Colored Materials: Two-Year Results

The aim of this two-year prospective clinical study was to evaluate and compare the clinical performance of three different adhesive esthetic materials in noncarious cervical lesions. A total of 90 restorations (30 per material) were placed in 30 patients who ranged in age between 18 and 50 years and of both genders, by a single operator with no previous preparation. The restoration of noncarious cervical lesions was done with either a microfilled composite (Esthet.X/Dentsply/De Trey, Konstanz, Germany, and Prime&Bond NT/Dentsply/De Trey), a nanohybrid composite (TetricEvoCeram/Vivadent, Schaan, Liechtenstein, and AdheSE/Vivadent), or a compomer (Dyract eXtra/Dentsply/De Trey and Xeno III Dentsply/De Trey). All restorations were evaluated by independent examiners using a modified US Public Health Service criteria at baseline and after 12 and 24 months for six clinical categories. Data were analyzed statistically by Pearson's chi-square or the Fisher's exact test at 5% significance level (p<0.05). Results showed that most of the restorations were clinically satisfactory after 12 and 24 months, with no statistically significant differences among the three groups for all evaluated criteria. Treatment of noncarious cervical lesions using composite and compomer materials, combined with the appropriate adhesive systems and properly implemented restorative procedures, gives satisfactory results after a two-year evaluation period.