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Purpose: To assess the biologic and technical responses to cemented and screw-retained all-ceramic single-tooth implant-supported reconstructions at 3 years postinsertion.Materials and Methods: Thirty-four patients with single-tooth implants were randomly restored with either a cemented lithium disilicate crown on a customized zirconia abutment (CEM) or a screw-retained crown with a directly veneered zirconia abutment (SCREW). At baseline examination and after 3 years of loading, marginal bone level and technical parameters were assessed. Differences in marginal bone loss were tested using Mann-Whitney U test at baseline and at 3 years, and changes within each group between baseline and 3 years were tested using Wilcoxon signed rank test.Results: The median changes between baseline and the 3-year follow-up amounted to -0.1 mm (CEM; intragroup P = .36) and -0.0 mm (SCREW; intragroup P = .58). Intergroup comparisons did not reveal statistically significant differences at 3 years (P = .20) or over time (P = .70).Conclusion: At 3 years, screw-retained and cemented reconstructions rendered largely the same radiographic and technical outcomes. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to test whether intraradicular posts of different colors induce different amounts of color change of the buccal gingiva. Twenty-three patients in need of a post-and-core buildup at one endodontically treated incisor, canine, or premolar were included. Titanium (Ti), zirconia (Zi), and glass fiber (Gf) posts were consecutively inserted in each test tooth. Spectrophotometric color measurement of the buccal gingiva was performed prior to post bed preparation and after insertion of Ti, Zi, and Gf posts. For control purposes, the gingival color at the contralateral vital tooth was assessed. The differences of color components ΔL, Δa, and Δb and the total color difference (ΔE) between different experimental conditions were obtained. ΔE value of 3.7 was considered the threshold value for intraoral color distinction. The gingival thickness at test teeth was measured. No difference occurred with regard to the amount of gingival discoloration induced by different posts. In the majority of cases, posts did not exhibit a visible influence on the color of buccal gingiva. The gingiva at endodontically treated teeth presented a visible discoloration compared to the gingiva at vital teeth. The degree of gingival discoloration at endodontically treated teeth was correlated with the gingival thickness, with more pronounced discolorations in cases of thinner soft tissue. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this research was to assess survival and complication rates of tooth- and implant-supported fixed dental prostheses (FDPs) and single crowns(SCs) after 5 years of function in a specific patient population group who underwent comprehensive prosthetic treatment. Materials and Methods: This retrospective study included a convenience sample of 52 patients who met specific inclusion and exclusion criteria and were treated during two specific courses as part of the undergraduate curriculum. The patients' prosthodontic treatment comprised 296 tooth-supported and 37 implant-supported SCs together with 76 tooth-supported and 15 implant-supported FDPs. Pre- and posttreatment clinical examinations included screening for biologic and technical complications, probing pocket depth, bleeding on probing (BoP), and plaque control record (PCR) as well as intraoral radiographs . Information was obtained from the patients about dental hygiene and dental visits,treated complications, and patient satisfaction during the observation period. Descriptive statistics were employed. Results: Forty-five patients were followed for a mean observation period of 5.26 ± 0.47 years. The survival rates were 99.0% for tooth-supported SCs, 98.7% for tooth-supported FDPs, and 100% for implant supported FDPs and SCs. Loss of vitality was observed in 2.9% of all abutment teeth deemed to be vital initially. Endodontic complications occurred in 5% and root fracture in 2.5% of nonvital abutment teeth. Caries was found in 0.4% of abutments. No framework or implant fractures were observed, but fracture of the veneering ceramic affected 3.8% of FDPs. The mean BoP was 21.5% ± 9.9%, and the mean PCR was 22.8% ± 16.5%. A high satisfaction rating was provided by 82.2% of patients.Conclusions: High survival and relatively few complication rates were observed for all prescribed FDPs over the observation period [ABSTRACT FROM AUTHOR]

The article presents a report on the comparison of cemented and screw-retained implant crowns with individualized zirconia abutments. It states that all-ceramic implant-supported crowns can be screwed and cemented crown can be made. It also states that inflammation can be caused by the occurance of cemented crowns of cement surpluses under the peri-implant mucosa.

This case report describes a minimally invasive step-by-step approach to treat a patient with amelogenesis imperfecta. This is a genetic developmental disorder of the dental enamel, which clinically manifests as white and dark discolorations of the teeth. The clinical examination did not reveal the true depth of the staining. Therefore, a step-wise treatment approach was chosen. The first step consisted of a home bleaching procedure, which led to a slight improvement of the esthetic appearance, but the stains were still clearly visible. The next step was the application of a microabrasion technique. This led to further improvement, but not to a satisfactory result for this patient who had high esthetic expectations. Thus, the third step was undertaken: it was planned to restore the maxillary incisors and canines with ceramic veneers. The dental technician prepared a wax-up, which served as a basis for a clinical mock-up. After discussing the mock-up and the treatment plan with the patient, crown lengthening was performed on teeth 11 and 23 to improve the pink esthetics. Subsequently, the teeth were prepared in a minimally invasive way and a final impression was taken. Following try-in, the six veneers were inserted with resin cement. [ABSTRACT FROM AUTHOR]

The purpose of this study was to test whether prosthetic treatment with different intraradicular posts influences the color of the buccal gingiva at teeth restored with zirconia crowns. A total of 31 patients in need of a full-coverage single crown at an endodontically treated premolar, canine, or incisor in the maxilla or the mandible were included. The patients were randomly assigned to receive composite build-ups using titanium (Ti), zirconia (Zi), or glass-fiber (Gf) posts or a build-up using no post at all (NP). All the teeth were restored with veneered zirconia single crowns. Spectrophotometric color measurements of the buccal gingiva were taken at the test teeth prior to and after the prosthetic treatment, and at the contralateral vital control tooth. The differences of the color components ΔL, Δa, and Δb and the total color difference ΔE between the test tooth prior to and after treatment and between the test and control tooth were calculated. The color differences were analyzed to determine whether they varied from 0 and 3.7, the threshold for detection by the human eye. Analysis of variance was performed to compare ΔE, ΔL, Δa, and Δb in the four post groups. The prosthetic treatment induced a significant color change ΔE in all the groups (Ti: ΔE1 = 6.4 ± 1.9; Zi: 7.1 ± 2.0; Gf: 6.2 ± 3.5; NP: 6.6 ± 3.5). There was no significant difference between Ti, Zi, Gf, and NP with respect to ΔE, ΔL, Δa, and Δb. Gingival color ΔE differed significantly between the test and control teeth before (Ti: ΔE = 6.8 ± 3.0; Zi: 9.0 ± 3.5; Gf: 5.7 ± 2.1; NP: 8.2 ± 2.8) and after prosthetic treatment (Ti: ΔE = 6.0 ± 2.8; Zi: 7.1 ± 2.9; Gf: 7.2 ± 3.0; NP: 6.9 ± 2.6). The use of different intraradicular posts (titanium, zirconia, glass fiber) or no post at all did not influence the color of the buccal gingiva at teeth restored with zirconia crowns. There was a significant gingival color difference between endodontically treated teeth and vital control teeth, both before and after prosthetic treatment.

A laboratory study was performed to assess the influence of beveling the margins of cavities and the effects on marginal adaptation of the application of ultrasound during setting and initial light curing. After minimal access cavities had been prepared with an 80 microm diamond bur, 80 box-only Class II cavities were prepared mesially and distally in 40 extracted human molars using four different oscillating diamond coated instruments: (A) a U-shaped PCS insert as the non-beveled control (EMS), (B) Bevelshape (Intensiv), (C) SonicSys (KaVo) and (D) SuperPrep (KaVo). In groups B-D, the time taken for additional bevel finishing was measured. The cavities were filled with a hybrid composite material in three increments. Ultrasound was also applied to one cavity per tooth before and during initial light curing (10 seconds). The specimens were subjected to thermomechanical stress in a computer-controlled masticator device. Marginal quality was assessed by scanning electron microscopy and the results were compared statistically. The additional time required for finishing was B > D > C (p < or = 0.05). In all groups, thermomechanical loading resulted in a decrease in marginal quality. Beveling resulted in higher values for "continuous" margins compared with that of the unbeveled controls. The latter showed better marginal quality at the axial walls when ultrasound was used. Beveling seems essential for good marginal adaptation but requires more preparation time. The use of ultrasonic vibrations may improve the marginal quality of unbeveled fillings and warrants further investigation.