ABSTRACT
Statement of the Problem: Fixed retainers were developed to maintain incisor alignments after orthodontic treatments. Although the effects of fixed retainers on periodontal health are clinically studied, no studies have still evaluated the histological changes in the periodontium after the placement of thefixed retainers
Purpose: The aim of this study was to evaluate the effects of customised retainers on periodontium histologically
Materials and Method: Forty pairs of maxillary and mandibular central incisors of twenty rabbits were randomly divided into four equal groups: The first group was considered as the control and in the second group, Fiber Reinforced Composite [FRC], in the third group, 0.014 inch stainless steel [SS] wire and in the fourth group, 0.175 inch multistrand stainless steel [MSS] wire were bonded on the labial surfaces of the incisors. After sixty days; animals' periodontium were evaluated histologically
Results: The number of bone resorption lacuna in the control group was significantly less than FRC and 0.014 SS groups. The periodontal vessel count and their diameter in the control group was significantly lower than the other groups. The pulp vessel count and their diameter in controls were significantly more than the 0.014 SS and the 0.175 MSS groups
Conclusion: Findings of this study suggest that FRC fixed retainer might cause detrimental effects on the periodontal ligaments and supporting bone and the 0.014- inch and 0.175- inch fixed retainers can cause hyalinization and possibly the necrosis of the pulp
ABSTRACT
Recurrent miscarriage is defined as the loss of three or more pregnancies. Recurrent Pregnancy Loss [RPL] is traditionally investigated after three or more consecutive losses. Although some believe that the investigation must be launched after two miscarriages, there is not enough compelling evidence to draw conclusion. In this cross-sectional study, we studied 58 women with two or more consecutive abortions [37 women with two and 21 women with three or more miscarriages] from 2005 to 2009. The following risk factors were analyzed and compared between the two groups: endocrine dysfunctions, genetic abnormalities, uterine anomalies, infections, thrombophilia, polycystic ovary syndrome, autoimmune disorders, sperm characteristics, and advanced maternal age. We did not find any known factor for pregnancy losses in 18 [31.03%] patients but in the rest, the most common cause of Recurrent pregnancy loss was endocrine disorders [41.4%]. The other causes were uterine abnormalities [12.1%], infections [12.1%], maternal age more than 35 years [12.1%], thrombophilia [8.6%], abnormal semen analysis [8.6%], genetic defects [6.9%] and autoimmune disorders [1.7%]. There were no significant differences between the two groups in regards with the causes of abortion except uterine abnormality [P=0.039] which was more frequent in women with three or more three miscarriages [23.8%] relative to women with two abortions [5.4%]. There were no significant differences between women with two or women with three or more three abortions in regards with the causes of abortion except uterine anomalies. Therefore, it seems quite reasonable and perhaps beneficial to start the investigation in patients with two abortions
ABSTRACT
Seedless barberry [Berberis vulgaris L. var. asperma] is one of the few crops that is only cultivated in eastern parts of Iran. As a new crop there has not been any study to identify phylogenetic relationships of this plant with other related species existing in Iran. In this study, Amplification fragment length polymorphism [AFLP] markers based on four selected primer combinations [EcoRI/Tru1I] were used to evaluate genetic variation and phylogenetic relationship among wild and cultivated barberry populations belonging to north east and eastern Iran. Two other species of ornamental barberry and one species of Mahonia aquifolium were also taken in this study. An Unweighted pair group method with arithmetic averages [UPGMA] dendrogram based on genetic distances clearly clustered each species, confirming phylogenetic relationships at the molecular level. These results can clarify the ambiguity in the relationship between Mahonia and Berberis genera. The heterozygosity index, principle coordinates analysis [PCoA], Fst Index and analysis of molecular variance [AMOVA] revealed a significant difference among wild barberry populations. As expected, observed variation within the cultivated barberry population was very low and close to zero. Moreover, morphological markers were used to evaluate variation and phylogenetic relationships among Berberis populations compared to results from AFLP markers by means of the Mantel correspondence test. No significant value was found by the mantel test between AFLP data and morphological markers. The lack of correlation between AFLP and morphological markers suggests low efficiency of identification key of Flora Iranica for classification and phylogenetic consideration of the Berberis family. Further molecular and morphological investigations are necessary to improve understanding of the relationships within species and genera of the Berberis family