[Histological evaluation of micro implant-bone interface following immediate versus delayed loading in a dog's mandibular bone]

Skeletal anchorage devices such as microimplants are successful attempts to have absolute anchorage. The aim of this study was to evaluate the effect of immediate and delayed orthodontic loading on maxillary and mandibular microimplants regarding histologic responses and bone implant contact [BIC] in a dog. Thirthy-two microimplants [Abso Anchor] were bilaterally placed in the mandibular premolar regions of four adult male dogs. The microimplants were divided into loaded and unloaded [control] groups. The control group had two subgroups of 4 and 8 weeks and the loaded group comprised two subgroups of immediate and delayed [after 4 weeks healing period] loading. Loaded samples were subjected to 200g load provided by Ni-Ti coil spring for 4 weeks. The decalcified specimens were prepared for histological examination under light microscope. The microimplants' surrounding tissue was observed histologically and the bone implant contact [BIC] percentage was calculated in each sample. Three way ANOVA was used to compare BICs in different groups. Mobility was detected in two mandibular microimplants, so the survival rate was calculated as 93.7%. BIC values were not significantly different between loaded and unloaded groups, and between immediate and delayed loaded groups. Immediate or delayed loading of microimplants does not load to significant difference in the bone-microimplant contact

[Evaluation of histologic changes of human dental pulp following orthodontic extrusive and intrusive forces]

Statement of Problem: Understanding the effects of orthodontic force on the pulp is of particular interest, especially because altered pulpal respiration rate, secondary dentin formation, internal root resorption, and even pulpal necrosis have all been associated with orthodontic treatment

Purpose: The aim of this study was to evaluate and compare the effects of orthodontic extrusive and intrusive forces on the histologic changes of the human dental pulp after 3 days and 3 weeks

Materials and Method: In this study, 52 sound upper first premolars from 26 patients, scheduled for extraction for orthodontic reasons, were selected. The patients were divided randomly into 2 groups [3 days and 3 weeks]. In each group, 10 teeth received orthodontic extrusive forces, 10 teeth underwent intrusive forces and 6 teeth served as controls. Histologic changes were evaluated and the data were statistically evaluated by nonparametric tests

Results: Vacuolization and disruption of the odontoblastic layer showed statistically significant differences between the control and either of the experimental groups in each test period. Furthermore, fibrous tissue formation in the extrusive group was significantly higher than the control group in the 3-week period. There was no significant difference between 3-day and 3-week intervals in each experimental group, except that fibrosis in the extrusive group was significantly increased after 3 weeks of force application. Comparison between extrusive and intrusive groups revealed no statistical significance in each test period

Conclusion: The results indicate that if orthodontic forces are applied in the optimal range and are not more intense than the physiological limit of tissue tolerance, irreversible injuries to the pulp can be prevented

[Evaluation of Adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma by immunohistochemistry]

Salivary gland tumors classification continuously undergoes alternations, especially in the recent years. This study used immunohistochemical markers for distinguishing between polymorphous low-grade adenocarcinoma [PLGA] and adenocarcinoma carcinoma [AdCC] which have several overlapping histological and clinical features. Ten AdCC and eight PLGA with five normal minor salivary glands were selected after review by two oral pathologists. LSAB method was used for seven markers: carcinoembryonic antigen, epithelial membrane antigen, muscle specific actin, vimentin, S 100, P53 and Ki-67. Finally, the data were analyzed by Mann-Whiteny test. Analysis of data showed a high expression of CEA, EMA and Ki-67 in AdCC compared to PLGA. Although, CEA [P<0.001] expression was limited to luminal cells .In contrast, MSA [P=0.034] expression in nonluminal cells, and Ki-67 [P<0.001] occurred in both luminal and nonluminal cells. Also there was highly expression of vimentin and S-100 in PLGA with no significancy for EMA and Tp53. The result of this study suggests that ICH can be a helpful tool. The immunostaining of AdCC and PLGA with CEA, Vimentin and Ki-67 were of greater significant, S-100 and MSA were less significant and the others [EMA and P53] could not offer an adjunctive aid in differential diagnosis between the two tumors

[Evaluation of the effect of progesterone on prevention of preterm delivery and its complications]

Preterm delivery is a major cause of prenatal mortality and morbidity in the world and results in increased obstetric and pediatric care costs. The purpose of this study was to evaluate the effects of prophylactic vaginal progesterone in decreasing the rate of preterm delivery and its complications in high risk women. This study included 150 asymptomatic women with high risk singleton pregnancies. The subjects were assigned randomly into two similar groups. One group received 100 mg of prophylactic vaginal progesterone therapy [n=75] daily between the 24th and 34th week of gestation and the other group received no treatment [n=75]. The two groups were similar regarding maternal age and preterm delivery risk factors. Uterine contractions were monitored by external tocodynamometer for 60 minutes and in case of true contractions, routine tocolytic drugs were started for the subjects. In some patients, in spite of receiving tocolytic drugs, delivery progressed and the related data were collected. Data were introduced into SPSS software and analyzed by means of chi square, exact Fischer, ManWitney U, and t tests. The results were reported with a confidence level of 95%. The mean gestational age at the time of delivery was higher in the interventional group [38.62 +/- 2.08 week vs. 35.88 +/- 3.5 week] [P=0.001]. Preterm delivery before the 37th week of gestation occurred in 11.6% and 31.9% of the subjects in the progesterone and control groups respectively [P=0.004] and preterm deliveries before the 34th week occurred in 22.2% and 2.9% of the women in the control and progesterone groups respectively [p=0.001]. Moreover respiratory distress syndrome, low birth weight, birth weight, need for oxygen, infant apgar,need for mechanical ventilator, and hospitalization in NICU were significantly different between the two groups [P<0.01]. Prophylactic vaginal progesterone reduced the frequency of uterine contractions which led to decreased rate of preterm delivery in women with high risk factors for preterm delivery

[Ten-year-evaluation of odontogenic cysts and tumors related to the impacted teeth]

Odontogenic cysts and tumors are associated with some lesions that impacted teeth are one of them. Impacted teeth are those cease to erupt before emergence. Varying incidences have been reported in different literature about this condition. The aim of this retrospective study was to achieve the sexual, location and age related distribution of odontogenic cysts and tumors and frequency of each one in relationship with an impacted tooth in order to prompt of clinician knowledge and easy selection of treatment plan. In this retrospective study, we used registration books and paraffinized blocks and slides of pathology archives of Mashhad dental school which had belonged to the patients involving with impacted teeth pathology, were evaluated from 1996-2006.Over all of these lesions were 304 cases in this period and relation between impaction of tooth and type of lesion was done by exact test. This study included 160 lesions consisting of 140 cysts [87.5%] and 20 tumors [12.5%]. Dentigerous cyst was the most common cyst [58.7%], and Odontoma was demonstrated to be the most common tumor [5%]. These lesions affected males [59.8%] more than females [41.2%] and they occurred with a pick in the second decade. The left-sided posterior mandible was more commonly involved by far. The findings of this study for Dentigerous cyst and Odontogenic keratocyst were similar to the findings of the other studies; nevertheless, Mandible and males predilection of Calcifying odontogenic cyst, one decade later involvement of Odontoma [3[rd] decade], one decade sooner involvement of Ameloblastoma [3[rd] decade], male predilection of Adenomatoid odontogenic tumor were not identical to the other studies, findings. However, more studies are recommended to achieve this purpose

[Plasma Cell Gingivitis [Case report]]

Plasma cell gingivitis is gingivitis which includes these clinical features: red and loosely gingival enlargement, sometimes is granular that with easy bleeding and usually does not cause attachment loss. In the histologic feature of this lesion there are closed plasma cells in under connective tissue that have extended to the oral epithelium. Causal factors include: allergic factors such as chewing gums, toothpaste, autoimmune reaction, hormonal imbalance and hematologic infiltration. However sometimes there is no clear cause. The aim of this study was case report of plasma cell gingivitis and the way to treat this lesion. The case was a 14 year-old girl whose chief complain was gingival bleeding. In an intra oral examination there was diffused red gingival enlargement in the anterior and right sextants of the jaw. In an extra oral examination there was no significant finding. Hematologic laboratory test was normal. In a radiographic feature, marginal bone loss was not detected and in a histopatologic feature there were acanthotic epithelium with closely infiltration of inflammatory cell with dominant plasma cell in under lamina properia. Surgery was performed by flap method in order to eliminate gingival enlargement and then the patient fallowed during the maintenance phase. In this case there was not any recurrence of the disease during the 6 month fallow up and any special allergic cause related to this patient was not detected. However, this patient was in pubertal age, and there may be a corelation to hormonal imbalance and this is one suggested causal factors

[Efficacy of oral naltrexone in treatment of pruritus in patients with eczema]

Regarding to the role of opioid receptors in peripheral cutaneous sensations and central itch procession, this study was designed to determine the efficacy of oral Naltrexone in the treatment of pruritus in patients with eczema in comparison with placebo. Thirty eight patients with eczema complaining of pruritus were studied. Pruritus scores were evaluated. Patients were given the placebo [n=20] or Nalterxone 50 mg [n=18] for a two-week period. During the study, pruritus scores were distinguished by a visual analogue scale [VAS] system and recorded in patients questionnaires three times, at the start of study, after 1 week, and after 2 weeks In the both groups VAS score were decreased, although Naltrexon was more effective than placebo in decreasing the VAS scores, both in 1st week week [P < 0.005] and 2[nd] week [P< 0.001]. Adverse events [mainly nausea and sedation were observed in 3 patients [2 in Naltrexon group and 1 in placebo group] Naltrexone is more effective than placebo in treatment of pruritus in patient affected with eczema. Naltrexone might be considered as an adjuvant remedy in treatment of pruritus

[ clinical and histological evaluation of human pulpal response after power bleaching]

"Power Bleaching" which is a new an in-office whitening technique with a combination of a whitening agent [peroxide] and an auxiliary [plasma-Arch light], has been claimed to be an effective and fast method in tooth bleaching. What is more important in using this method is the maintenance of the pulp health after tooth whitening. The aim of this study was to evaluate the human pulpal response after bleaching with H2o2 38% and plasma-Arc light. Eighty seven sound first premolars from 27 patients were selected and divided into 3 groups of 29, based on the time intervals of histologic evaluation. In each group 9 teeth were considered as a control. Vitality tests were done before bleaching [base line] and in four intervals of 2, 7, 30 and 60 days, but histologic evaluation was performed in three intervals 2, 7 and 60 days. Immediately after extraction, apical one third of the roots were sectioned off and each specimen was placed in 10% buffered formalin solution for pulpal fixation. EDTA was used for decalcification and sections were prepared from each specimen and stained with H and E and subsequently assessed microscopically for the following criteria: Irregularities in the odontoblastic layer, the presence of inflammatory cell, vasodilatation and pulpal fibrosis. Data was analyzed using Friedman test and Wilcoxon test [alpha= 0.05]. There were significant differences between the 2 and 60 days groups and between 7 and 60 days groups with respect to inflammatory responses and vasodilatation [p<0.05]. Comparison of the control and experimental groups of the 2 and 7 days revealed statistically significant differences in inflammation and vasodilatation [p<0.05]. No patient had experienced sensitivity, after different bleaching periods. Bleaching of teeth with H2o2 38% and plasma-Arc light might cause slight to moderate pulp reactions after 2 and 7 days confined to the coronal pulp. However, the observed histological changes did not affect the overall health of the pulp tissue permanently

[Multiple endocrine Neoplasia type 2B [MEN2B] [A case report]]

Multiple endocrine neoplasia syndrome [Type 2B] is a condition associated with systemic malignancies and posses orofacial manifestations. The oral mamifestations help clinician to diagnose disease in early ages. In this article a case is reported with MEN2B syndrome which was diagnosed on the basis of orofacial findings. An eight years old boy was refered for routine dental cares to Mashhad Dental School. In clinical examinations, multiple papules [which defined as neuroma by histopathologic examination] was found on the lip comissures, tip of the tounge and margin of lower eyelids. He had long, narrow face, high arched palate and eversion of eyelids. On the basis of oral and ocular findings, the diagnosis of MEN2B syndrome was made and the patient was refered to a pediatric endocrinologist. Thyroid scan showed cold nodules in thyroid gland which was confirmed by histopathologic examination as medullary carcinoma after total thyroidectomy. Epinephrine and neurepinephrine metabolites were high in urine analysiy setting him in suspicion to develop pheochromocytoma in future. Now the patient is under specialist control. Early diagnosis of MEN2B syndrome is necessary for successful treatment. The dentist may be the first one who diagnoses this syndrome by it's orofacial signs. So Dentists should be aware of oral findings of this disease

[ comparative study on the clinical diagnosis and pathology report of patients undergone biopsy at department of oral medicine of Mashhad dental school from 2002 until 2004]

The purpose of this study was to evaluate the concordance between clinical diagnosis and pathology report of patients referring to department of oral medicine of Mashhad dental school. In this descriptive retrospective study, personal information and disease [or lesion] characteristics of 170 patients who had been referred to the department of oral medicine for biopsy during the past 2 years, were collected through questionnaires and were analyzed Chi-square and Fisher exat statistical tests. The diagrams were drawn with use of Microsoft office SPSS software. 81.2% of the clinical diagnosis were consistent with pathology reports. In 18.8%, the clinical diagnosis was not confirmed histopathologically. The greatest concordance was observed for lichen planus, inflammatory hyperplasia and leukoplakia whereas pemphigus, SCC and systemic lupus erythematosus revealed the lowest concordance. Although a great concordance was observed between clinical diagnosis and pathology report, the inconcordance was significant and establishing strategies for minimizing it, is necessitated

histopathologic study on pulp response to glass ionomer cements in human teeth

Despite the wide range of new dental materials, there is still a need for biomaterials demonstrating high biocompatibility, antimicrobial effects and ideal mechanical properties. The aim of this study was to histologically evaluate the pulpal response to a conventional glass ionomer, a resin modified glass ionomer and a calcium hydroxide in human teeth. Fifty five deep class V cavities were prepared in premolars of 31 patients and were divided into 3 groups based on application of the following liners: resin modified glass ionomer [Vivaglass Liner], conventional glass ionomer [Chembond Superior] and calcium hydroxide [Dycal]. After applying varnish, teeth were filled with amalgam. Each group was further divided into three subgroups according to time intervals of 7, 30 and 60 days. Teeth were then extracted and their crowns were fixed in formalin. Each sample was assessed microscopically for odontoblastic changes, inflammatory cell infiltration, reactionary dentin formation, remaining dentinal thickness and presence of microorganisms. Statistical analysis including Kruskal Wallis and Mann Whitney was carried out for comparison of mean ranks. [P=0.05]. In the Vivaglass Liner group, pulpal response was significantly higher on day 7 as compared to days 30 and 60 [P<0.05]. Reactionary dentin production was significantly lower after 7 days than after 60 days for all materials [P<0.05]. There was no statistically significant difference in pulpal responses among the three groups during the same time intervals [P>0.05]. There was no correlation between pulpal responses with micro-organisms and remaining dentin thickness [P>0.05]. According to the results of this study, light-cured glass ionomer as well as the other tested lining materials were determined to be biologically compatible with vital pulps in deep cavities of sound human teeth

comparison study of AgNORs staining in human oral normal mucosa verrucous carcinoma and squamous cell carcinoma

The value of Silver Staining of nucleolar organizer regions [AgNOR] counts as a diagnostic aid has been reported for several neoplastic entities. The aim of this study to determine the evaluation of the expression of AgNOR as a marker of proliferation in squamous cell carcinoma grade I, verrucous carcinoma and oral normal mucosa. Silver-Stain nucleolar organizer regions AgNORs were counted in sections from formalin fixed paraffin embedded blocks of 20 cases of well-differentiated squamous cell carcinoma, 20 cases of verrucous carcinoma and 10 cases of normal oral mucosa. Two methods of AgNORs counting were used. The mean number of AgNOR nucleus [M AgNORs] and determination cells containing 3 or more AgNORs/ nucleus [P AgNOR] as indicator of the proliferative activity of the cells. Statistical differences were found between normal oral mucosa, verrucous carcinoma WD squamous cell in AgNOR related parameters. AgNOR would be a quantitative, discriminative aid, easy to monitor in a pathology laboratory in detection incipient cellular alterations and contribute to the issue of early diagnosis and to the knowledge of tumoral growth