Assessment of Static and Dynamic Load Tolerance of the Implant Mounts on its Particular Implant.

Objectives: We compared the loads at which the implant holders from Astra Tech (AST) (AstraOsseoSpeed) and Osseotite Certain failed under static compression after experiencing fatigue, as well as the gap that resulted from dynamic loading between the implant-holder complexes. Materials and Method: The ISO 14801 recommendation served as the foundation for the test protocol. Each brand's five implant-implant holder assemblies underwent dynamic loading. A load of 200 N was applied at a stress frequency of 12 Hz and a cycle rate of 5105. (Eden Prairie, MN, USA). Using scanning electron microscopy (S3700N, HITACHI, Japan), the gap (m) at the interface was measured post-fatigue. Static loading was then used to determine the highest load (N) after the point of failure. Controls included definitive abutment-implant complexes. Statistics were used to analyze the data. Result: The Osseotite Certain group showed a slight trend toward greater resistance, but there was no diversity among the two implant holder groups (P 0.05). AST (AstraOsseoSpeed) implants had a larger interface gap, but the difference was not statistically significant. Conclusion: With respect to greatest compression load or the interface gap following dynamic loading, there were no discernible differences between the two experimental groups.

Spirometric Assessment of Impact of Complete Dentures on Respiratory Performance: An in vitro Study.

INTRODUCTION: Edentulism is one of the debilitating states affecting a significant portion of the geriatric population. It is often considered as the ultimate marker for predicting the pressure and burden on oral health. Respiration is also a routine vital function running continuously through the human body and most commonly assessed by a spirometer. Hence, we planned the present study to assess the impact of complete dentures on the functioning of the respiratory system. MATERIALS AND METHODS: In the present study, a spirometric assessment of the effect of complete dentures on respiratory performance was done. A total of 100 subjects were included, and diagnostic spirometer was used for carrying out the spiro-metric test at different stages of each subject. The spirometric test was carried out at four different stages: In the absence of both the denture (AODs), with both the dentures (maxillary and mandibular) inserted in the patient's mouth (BDs), with only maxillary denture inserted in the oral cavity (UDs), and finally, by inserting only the mandibular dentures in the oral cavity (LDs). Forced vital capacity (FVC), peak expiratory flow (PEF), forced expiratory volume in 1 second (FEV1), and forced expiratory flow between 25 and 75% (FEF25-75) were evaluated. All the results were compiled and assessed using Statistical Package for the Social Sciences (SPSS) software. RESULTS: Of the total 100 subjects included in the study, 42 were males and 58 were females. The mean FVC values of AOD, BD, LD, and UD group were 3.10, 3.02, 2.90, and 2.93 respectively. The mean PEF values of AOD, BD, LD, and UD group were 5.79, 5.60, 5.40, and 5.48 respectively; 2.39, 2.35, 2.33, and 2.32 were the mean FEV1 values observed in AOD, BD, LD, and UD group respectively. Statistically significant results were obtained while comparing AOD-FVC and BD-FVC and other oral conditions. CONCLUSION: Spirometric values of respiratory functional tests in edentulous patients might be unfavorably affected by wearing complete dentures. CLINICAL SIGNIFICANCE: Since subjects without complete dentures exhibited a maximum value of respiratory functional test, respiratory exercise protocols should also be carried in denture-wearing edentulous patients for increasing the performance of the respiratory system.

SHED - Basic Structure for Stem Cell Research.

The discovery that stem cells from dental pulp are capable of differentiating into endothelial cells raised the exciting possibility that these cells can be a single source of odontoblasts and vascular networks in dental tissue engineering. These so-called mesenchymal stem cell populations have been identified from human exfoliated deciduous teeth because of their ability to generate clonogenic adherent colonies when grown and expanded. In addition to these stem cells, other population of stem cells can be from adult human dental pulp and periodontal ligament. The identification and isolation of these stem cells in adult dental pulp was first reported by Gronthos and co-workers in 2000.These dental pulp stem cells have clonogenic abilities, rapid proliferative rates and the capacity to form mineralized tissues both in vitro and in vivo. The stem cells from human exfoliated deciduous teeth are distinct from dental pulp stem cells by virtue of their proliferation rate, increased cell population doublings and osteoinductive capacity in vivo. It is further demonstrated that human exfoliated deciduous teeth stem cells may not be a single-cell type, may well be a heterogenous population of cells from the pulp.