Long-term Pulpal and Restorative Outcomes of Pulpotomy in Mature Permanent Teeth.

INTRODUCTION: Pulpotomy in mature permanent cariously exposed teeth preserves the remaining pulp tissues, but long-term outcomes of the pulp and the restoration are unknown. This prospective study examined the immediate and long-term status of the pulp and the restored tooth and identified potential predictors of early and late failures in teeth that were asymptomatic or experiencing only mild symptoms at the time of treatment. METHODS: Pulpotomy was performed using the aseptic technique and a tricalcium silicate cement under local anesthesia. Teeth were assessed for up to 5 years for pulpal and apical signs and symptoms, restorative marginal integrity, and periodontal health. RESULTS: Fifty-two patients (61 teeth) with a median age of 40 years (range, 21-75 years) were included in this study; 17 (32.7%) men and 35 (67.3%) women were treated and reviewed. Overall pulp survival was 90.2% (95% confidence interval, 79.8%-96.3%); 6 teeth developed irreversible pulpitis or pulp necrosis when the restoration was intact. Preoperative pain was a potential predictor (P < .05) for early failure. Eleven late failures occurred between 2 and 4 years: 1 tooth with intact coronal restoration had pulp necrosis and asymptomatic apical periodontitis, 4 had recurrent caries resulting in asymptomatic apical periodontitis, 4 remained vital and only needed new restorations, 1 was unrestorable, and 1 was extracted for periodontal reasons. The type of definitive restoration was a potential predictor for late failure (P < .05). CONCLUSIONS: Carious pulp exposures in asymptomatic mature permanent teeth can be predictably managed by pulpotomy using a tricalcium silicate cement. Short-term failures were few and managed by pulpectomy. Appropriate coronal restoration is critical to long-term success.

Catabolism of the Last Two Steroid Rings in Mycobacterium tuberculosis and Other Bacteria.

Most mycolic acid-containing actinobacteria and some proteobacteria use steroids as growth substrates, but the catabolism of the last two steroid rings has yet to be elucidated. In Mycobacterium tuberculosis, this pathway includes virulence determinants and has been proposed to be encoded by the KstR2-regulated genes, which include a predicted coenzyme A (CoA) transferase gene (ipdAB) and an acyl-CoA reductase gene (ipdC). In the presence of cholesterol, ΔipdC and ΔipdAB mutants of either M. tuberculosis or Rhodococcus jostii strain RHA1 accumulated previously undescribed metabolites: 3aα-H-4α(carboxyl-CoA)-5-hydroxy-7aß-methylhexahydro-1-indanone (5-OH HIC-CoA) and (R)-2-(2-carboxyethyl)-3-methyl-6-oxocyclohex-1-ene-1-carboxyl-CoA (COCHEA-CoA), respectively. A ΔfadE32 mutant of Mycobacterium smegmatis accumulated 4-methyl-5-oxo-octanedioic acid (MOODA). Incubation of synthetic 5-OH HIC-CoA with purified IpdF, IpdC, and enoyl-CoA hydratase 20 (EchA20), a crotonase superfamily member, yielded COCHEA-CoA and, upon further incubation with IpdAB and a CoA thiolase, yielded MOODA-CoA. Based on these studies, we propose a pathway for the final steps of steroid catabolism in which the 5-member ring is hydrolyzed by EchA20, followed by hydrolysis of the 6-member ring by IpdAB. Metabolites accumulated by ΔipdF and ΔechA20 mutants support the model. The conservation of these genes in known steroid-degrading bacteria suggests that the pathway is shared. This pathway further predicts that cholesterol catabolism yields four propionyl-CoAs, four acetyl-CoAs, one pyruvate, and one succinyl-CoA. Finally, a ΔipdAB M. tuberculosis mutant did not survive in macrophages and displayed severely depleted CoASH levels that correlated with a cholesterol-dependent toxicity. Our results together with the developed tools provide a basis for further elucidating bacterial steroid catabolism and virulence determinants in M. tuberculosis.IMPORTANCE Bacteria are the only known steroid degraders, but the pathway responsible for degrading the last two steroid rings has yet to be elucidated. In Mycobacterium tuberculosis, this pathway includes virulence determinants. Using a series of mutants in M. tuberculosis and related bacteria, we identified a number of novel CoA thioesters as pathway intermediates. Analysis of the metabolites combined with enzymological studies establishes how the last two steroid rings are hydrolytically opened by enzymes encoded by the KstR2 regulon. Our results provide experimental evidence for novel ring-degrading enzymes, significantly advance our understanding of bacterial steroid catabolism, and identify a previously uncharacterized cholesterol-dependent toxicity that may facilitate the development of novel tuberculosis therapeutics.

In vitro analysis of riboflavin-modified, experimental, two-step etch-and-rinse dentin adhesive: Fourier transform infrared spectroscopy and micro-Raman studies.

To modify two-step experimental etch-and-rinse dentin adhesive with different concentrations of riboflavin and to study its effect on the bond strength, degree of conversion, along with resin infiltration within the demineralized dentin substrate, an experimental adhesive-system was modified with different concentrations of riboflavin (m/m, 0, 1%, 3%, 5% and 10%). Dentin surfaces were etched with 37% phosphoric acid, bonded with respective adhesives, restored with restorative composite-resin, and sectioned into resin-dentin slabs and beams to be stored for 24 h or 9 months in artificial saliva. Micro-tensile bond testing was performed with scanning electron microscopy to analyse the failure of debonded beams. The degree of conversion was evaluated with Fourier transform infrared spectroscopy (FTIR) at different time points along with micro-Raman spectroscopy analysis. Data was analyzed with one-way and two-way analysis of variance followed by Tukey's for pair-wise comparison. Modification with 1% and 3% riboflavin increased the micro-tensile bond strength compared to the control at 24 h and 9-month storage with no significant differences in degree of conversion (P<0.05). The most predominant failure mode was the mixed fracture among all specimens except 10% riboflavin-modified adhesive specimens where cohesive failure was predominant. Raman analysis revealed that 1% and 3% riboflavin adhesives specimens showed relatively higher resin infiltration. The incorporation of riboflavin in the experimental two-step etch-and-rinse adhesive at 3% (m/m) improved the immediate bond strengths and bond durability after 9-month storage in artificial saliva without adversely affecting the degree of conversion of the adhesive monomers and resin infiltration.

Do patients' perceptions exceed their expectations in private healthcare settings?

PURPOSE: The purpose of this paper is to investigate whether patients' perceptions exceed expectations when seeking treatment in private healthcare settings in the Klang Valley Region of Malaysia. DESIGN/METHODOLOGY/APPROACH: A survey was conducted among 191 patients in the Klang Valley Region of Malaysia to measure service quality of the private healthcare setting in Malaysia using SERVQUAL 5 dimensions model by Parasuraman et al. and three additional dimensions of the human element, when it comes to rendering good healthcare services, i.e. courtesy, communication and understanding of customers. FINDINGS: The results revealed that the customers' perceptions did not exceed their expectations, as they were dissatisfied with the level of healthcare services rendered by private healthcare settings in that they felt that the waiting time of more than an hour to receive the service was excessive and, when there was a problem, the healthcare provider did not provide a response fast enough. RESEARCH LIMITATIONS/IMPLICATIONS: Only eight service quality dimensions were studied. The sample investigated is relatively small, where three private healthcare settings were selected. PRACTICAL IMPLICATIONS: It is recommended that hospital management should look into highlighted areas for which patients have high expectations. ORIGINALITY/VALUE: The paper adds to the existing body of research on healthcare service quality, particularly on patients' perceptions and expectations. Survey results should be useful for continuous quality improvement.

A comparison of human elements and nonhuman elements in private health care settings: customers' perceptions and expectations.

In today's highly competitive health care environment, many private health care settings are now looking into customer service indicators to learn customers' perceptions and determine whether they are meeting customers' expectations in order to ensure that their customers are satisfied with the services. This research paper aims to investigate whether the human elements were more important than the nonhuman elements in private health care settings. We used the internationally renowned SERVQUAL five-dimension model plus three additional dimensions-courtesy, communication, and understanding of customers of the human element-when evaluating health care services. A total of 191 respondents from three private health care settings in the Klang Valley region of Malaysia were investigated. Descriptive statistics were calculated by the Statistical Package for Social Sciences (SPSS) computer program, version 15. Interestingly, the results suggested that customers nowadays have very high expectations especially when it comes to the treatment they are receiving. Overall, the research indicated that the human elements were more important than the nonhuman element in private health care settings. Hospital management should look further to improve on areas that have been highlighted. Implications for management practice and directions for future research are discussed.

Load-fatigue performance of gold crowns luted with resin cements.

STATEMENT OF PROBLEM: Resin cements have gained popularity over the past few years because of their improved physical properties. There is a need to test these cements under fatigue loading, as there is growing recognition that fatigue testing is more clinically relevant than traditional monotonic static tests. PURPOSE: This study investigated the load-fatigue performance of complete gold crowns cemented with 4 types of resin cement. MATERIAL AND METHODS: Four resin cements (C & B Opaque [CBO], Calibra Esthetic [CE], RelyX Unicem [RU], and Panavia F [PF]) and a control, zinc phosphate cement (HY-Bond [HBZPC]) were tested. Fifty human maxillary premolars were prepared to an occluso-cervical dimension of 4 mm and a convergence angle of 20 degrees. Complete gold crowns were cast (Strator 3) and cemented with 1 of the 5 cements (n=10). A fatigue load of 73.5 N was applied at an angle of 135 degrees to the long axis of each tooth-crown specimen. Preliminary failure was defined as the propagation of a crack in or around the crown luting cement layer. The number of cycles to preliminary failure and the cement failure location were determined. Significant differences in cycles to preliminary failure were assessed by the nonparametric Kruskal-Wallis test, with follow-up Mann-Whitney tests (alpha=.05). RESULTS: Group CE had the highest rank of cycles to preliminary failure, while HBZPC had the lowest cycles to preliminary failure. Group CE had a significantly higher failure cycle count compared to PF (P=.016), RU (P=.001), and HBZPC (P<.001), but was not significantly different from CBO (P=.112). There was no significant difference in the failure cycle count between RU and HBZPC (P=.070). CONCLUSION: Not all tested resin cements had a superior fatigue life when compared with zinc phosphate cement. Of the 4 resin cement groups, Groups CE, CBO, and PF were significantly superior to HBZPC.