Effect of sandblasting on fracture load of titanium ceramic crowns

Purpose of the Study:

It is difficult to achieve a reliable bond between the titanium and veneering porcelain. The aim of this study was to evaluate the bond strength between titanium ceramic crowns.

Materials and Methods:

The surfaces of titanium copings were divided in two groups. Group A sandblasted with 250 um (n = 10) and Group B without sandblasting (n = 10). Low-fusing porcelain was bonded over copings. A universal testing machine was used to determine the fracture load (N) of the crowns. All data were compared using Student''s t-test.

Results:

There was a significant difference in fracture toughness between two groups (P = 0.05). The mean value of fracture strength for Group A was 721.66 N and for Group B was 396.39 N.

Conclusions:

Sandblasting improves the bond strength between titanium, and ceramic, mechanical bonding plays a crucial role in the bonding between titanium and ceramic.Key Words: Bonding, fracture load, sandblasting, titanium     

The Effect of Alloplastic Bone Graft and Absorbable Gelatin Sponge in Prevention of Periodontal Defects on the Distal Aspect of Mandibular Second Molars,After Surgical Removal of Impacted Mandibular Third Molar: A Comparative Prospective Study

Aim

Recent studies claim that haemostatic agents can be used as bone graft substitutes. The aim of this study was to compare the efficacy of alloplastic bone graft with absorbable gelatin sponge in prevention of periodontal defects distal to mandibular second molar after the surgical removal of impacted mandibular third molars.

Materials and methods

A prospective, randomized, single-blind split-mouth study was designed. The study consisted of 25 patients requiring surgical removal of bilateral impacted mandibular 3rd molars. The surgical sites were randomly divided into 2 groups: group I: G-graft (hydroxyapatite + collagen, study group) and group II: Abgel (absorbable gelatin sponge, control group). Patients were recalled on lst and 7th postoperative days and 3rd and 6th postoperative months. Probing depth, alveolar bone levels and soft tissue wound healing were evaluated. Paired t test was used to compare pre and post-operative alveolar bone levels and probing depth (PD). Wilcoxon signed ranks test was used to compare the wound healing.

Results

The soft tissue wound healing, PD and the distance between the cemento–enamel junction on the distal aspect of mandibular second molar (point A) and the alveolar crest on the distal aspect of the same tooth (point B) were significantly higher in group I as compared to group II.

Conclusion

This study reveals an increase in the alveolar bone level, improvement of PD and better wound healing in group I. Group II subjects required longer healing time than the normal. The authors disagree the claim that the haemostatic agents can be used as bone graft substitutes. However, long-term, multicenter, randomized controlled clinical trials are required.     

Antiplasmodial activity-aided isolation and identification of quercetin-4’-methyl ether in Chromolaena odorata leaf fraction with high activity against chloroquine-resistant Plasmodium falciparum

The present study was undertaken to evaluate the antiplasmodial activity of Chromolaena odorata leaf extract and gradient fractions through in vivo and in vitro tests, aimed at identifying its antiplasmodial constituents. Sub-fractions obtained from the most active gradient fraction were further tested for cytotoxicity against THP-1 cells, chloroquine-sensitive (HB3) and chloroquine-resistant (FCM29) Plasmodium falciparum. Our results showed the dichloromethane gradient fraction was most effective, significantly (P?50 of 4.8 and 6.74 μg/ml against P. falciparum HB3 and FCM29, respectively. Cytotoxicity of DF11 was estimated to be above 50 μg/ml, and its separation by column chromatography yielded a flavonoid which was characterized as 3, 5, 7, 3’ tetrahydroxy-4’-methoxyflavone from its spectroscopic data. It significantly suppressed infection (65.43–81.48 %) in mice at 2.5–5 mg/kg doses and compared favourably with the effects of chloroquine and artemisinin. It may therefore serve as a useful phytochemical and antiplasmodial activity marker of C. odorata leaves, which exhibit potential for development as medicine against malaria.     

Neonatal Severe Hyperparathyroidism due to Compound Heterozygous Mutation of Calcium Sensing Receptor (CaSR) Gene Presenting as Encephalopathy

The authors report a 14-d-old neonate who presented with lethargy, polyuria and dehydration and was found to have severe hypercalcemia with hyperparathyroidism. This neonate was treated with saline hydration, diuresis and injection pamidronate. Genetic analysis revealed a compound heterozygous mutation of CaSR.     

Quality of life in bipolar and schizoaffective disorder — A naturalistic approach

Purpose

The aim of this study was to evaluate the health-related quality of life (HRQoL) in bipolar type I (BD I) and schizoaffective (SQA) patients during a 2-year period in a naturalistic study.

Methods

This study was based on the data generated by the Bipolar Comprehensive Outcome Study, a prospective, non-interventional, observational study of participants with BD I and SQA disorder. Mixed-Model Repeated Measures Analysis was used to analyze changes in the SF-36 and EQ-5D.

Results

Participants exhibited low health status at baseline with SF-36 mean scores of 46.7 ± 10.5 and 36.9 ± 12.9 (best imaginable health = 100, normal population ≈ 50) for physical and mental components, respectively. No significant differences were found between the ratings of the BD I and SQA patients on HRQoL. The SF-36 SMC improved significantly over 24 months although SPC scores remained consistent across the study. On the whole, the lowest SMC score was observed among the depressed patients (38.20), followed by the patients with a mixed state (39.01) and the manic patients (39.83).

Limitations

The observational design may have limited the causal relationships and the generalizability within the current findings.

Conclusions

HRQoL was significantly impaired in all stages of BD and SQA when compared to the general population. The impairment of HRQoL was most pronounced in the depressed state, followed by the mixed state and then the manic state. The euthymic patients showed the least impairment. In addition, patients showed a global improvement in their mental health satisfaction over the 2 years follow up period.