Journal of Dental Medicine

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Growth factors are biological mediators that have a key roll in proliferation, chemotaxy and differentiation by acting on specific receptors on the surface of cells and regulating events in wound healing.They can be considered hormones that are not released in to the blood stream but have one a local action. Some of these factors can regulate premature change in GO to Gl phase in cell devesion cycle and even may stimulate synthesis of DNA in suitable cells, Growth substances, primarily secreted by fibroblasts, endothelia! cells, macrophages and platelet, include platelet derived growth factor (PDGF), insulin like growth factor (IGF) transforming growth factor (TGF)a and (3 and bone morphogenetic proteins BMPs that approximately are the most important of them. (BMP)s could be used to control events during periodontal, craniofacial and implant wound healing through favoring bone formation According toLynch, combination of PGDF and IGF1 would be effective in promoting growth of all the components of the periodontium.The aim of this study was to characterize growth factor and review the literature to determine the mechanism of their function, classification and application in implant and periodontal treatment.

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The root trunk (RT) of molar teeth is important diagnostic parameter that has a key roll in diagnosis and treatment planning.The purpose of this study is presenting a normal index of RT in mandibular molar teeth in different buccal (B). distal (D), Lingual (Li) and mesial (M) entrances, and to compare them with each other.It is a case series study that 351 extracted molar teeth, after removal of soft tissue and debridement of calculus, evaluated with gauge (with accuracy 0.1 mm) According to our measurement:In maxilla: M-side: 3.88± 0.15 mm, B-side: 4.7± 1.7. D- side: 4.87± 0.13mm. So with P.value <0.05 M and D RT are longer than and M RT is shorter than D RT.In mandibule: B- side: 2.73± 0.11mm and L side: 4.03±- 0.13mm. So with P.value < 0.01 Li RT is longer than B RT.According to ochsenbine classification our studying teeth have medium to long RT. We prescribe for educating the crater therapy in periodontal surgery the emphasize must be focused on craters with medium and long RT.The shortness of RT in B-side of lower molars needed the most attention during osteoctomy in resective procedures. Because RT not depended to underlying factors such as age, social and economic situation,and for large amount of sample size in our study, the result could be extended in Tehran.

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Statement of Problem: The goal of bone regenerative therapy is to reconstruct the damaged tissues to initial condition, which seems so important in periodontoiogy and implantology. In such therapies, different biomaterials, with some advantages and disadvantages, may by use.
Purpose: The aim of this research was to evaluate the quality, bone trabecular density and thickness of newly forming bone as well as foreign body reaction against Biostite®, in comparison with the control group.
Material and Methods: In this experimental study the total number of 5 sheep was operated with general anesthesia. At first 10 standard defects were created in 5x5x5mm on the left and right edentulous mandibular ridge. Five defects were randomly treated by Biostite®, the remaining five were considered as controls. After six months, the sheep were sacrificed and the separated defect areas with intact margin
were placed in 10% formaline and prepared for histologic and histomorphometric study. To analyze the data, Mann-Whitney U test was used.
Results: The mean percentage of new bone formation in Biostite® group was statistically more than the control group (PO.05). Newly formed bone was vital in both groups which was a combination of lamellar and woven types, however, the thickness and density of new bone in biostite® group was more than the controls. Foreign body reaction was observed in Biostite® group.
Conclusion: It is suggested that Biostite® synthetic material can be useful in bone regenerative
therapies.

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Statement of Problem: One of the best ways for treatment of Aggressive Periodontitis (AP) is identification and elimination of etiologic factors specially two microorganisms Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) in patients harboring them.

Purpose: This study determines the prevalence of Aa and Pg and its correlation with age, sex and the number of family members as well as probing pocket depth (PPD) in active sites of AP patients, referred to department of periodontics, Faculty of Dentistry, Tehran University of Medical Sciences.

Materials and Methods: In this cross sectional, descriptive study, 54 sites (PPD> 5mm) in 15 patients were considered for culture. Marginal gingiva was dried and sampling performed by paperpoint (#30). The selective medium for Aa, was Trypticase Soy Agar-Bacitracin- Vancomycin (TSBV) and for Pg was Brucella agar.Results were analyzed using Fisher and Chi-Square statistical tests.

Results: Thirteen patients or 38 sites (70.4%) were identified as Aa positive and 3 patients or 10 sites (18.4%) were Pg positive. There was no significant relation between the presence of Aa and sex or age (P=0.086). Pg was more prevalent in men compared with women (P<0.0001) but with regard to age there was no statistical difference between men and women. Aa had a significant positive correlation with PPD (P=0.002), which was not true for Pg. In addition, the number of positive sites showed a significant negative correlation with the number of family members.

Conclusion: Based on the present study, the prevalence of Aa in deep pockets in patients with AP is higher than Pg.

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Background and Aim: Several biomaterials have been presented for regeneration of intraosseous defects and Bio-Oss is one of the most accepted materials in this field. Neo-Oss may be the first and only regenerative material made in Iran which few studies have been published about it. The aim of this study was the histologic evaluation of Neo-Oss in comparison with Bio-Oss in experimental rabbit calvarial defects. Materials and Methods: This was an interventional in vivo study. After elevating muccoperiosteal flap 18 standard defects (3×6mm) in frontal & parietal bone were made by round bur on the calvarium of 6 New Zealand rabbits. Defects were randomly assigned to one of the following treatments: 1-No graft (control), 2-Bio-Oss graft 3-Neo-Oss graft. After 4 weeks the animals were killed and histologic sections prepared. The studied variables consisted of inflammation, type of regenerated bone, thickness of bony trabeculation and foreign body reaction. Data were analyzed by Friedman test with p<0.05 as the limit of significance.

Results: The results showed that Bio-Oss was effective for bone regeneration. Inflammation (P= 0.026) and foreign body reaction (P= 0.002) in Neo-Oss was significantly more than Bio-Oss group. Thickness of terabecula in Neo-Oss group (66.7% thin) was significantly different from Bio-Oss (100% thick) and control group (50% thin 50% thick) (P= 0.006). In Neo-Oss group, granulation tissue containing giant cells was observed and the rate of resorption during 4 weeks was high.

Conclusion: Based on the results of this study, the healing capacity of Neo-Oss in comparison with Bio-Oss is not acceptable.

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Background and Aim: Several risk factors directly affect the development of periodontal diseases. Also some systemic diseases act indirectly as predisposing and aggrevating factors. Osteoporosis is one of these factors and one of its main causes is lack of physical activity in postmenopause period. The incidence of osteoporosis is increasing in our country. The goal of this study was to evaluate the periodontal condition of women with osteoporosis and osteopenia referred to bone densitometric division of Loghman hospital in 2003 and compare to control group.

Materials and Methods: In this case control study based on BMD (Bone Mineral Density) measurement of back and thigh using DEXA method, 60 patients referred to bone densitometric division of Loghman hospital, were randomly selected. Cases were divided into three groups, 20 with osteoporosis, 20 with osteopenia and 20 normal cases. Periodontal indices consisting of plaque index (PI), tooth loss (TL), gingival recession (GR), probing pocket depth (PPD) and papilla bleeding index (PBI) were evaluated by clinical and radiographic examination. Data were analyzed by Kruskall Wallis and Dunn tests with p<0.05 as the limit of significance.

Results: PBI, PI and TL were significantly higher in osteoporotic group than osteopenic and normal group. PPD was not different in the three groups. Due to the low prevalence of recession in our study, this parameter was not included in the statistical analysis.

Conclusion: It seems that osteoporosis does not increase the incidence of periodontal diseases because it affects bone quality rather than quantity. In osteoporosis calcium deficiency and increasing age lead to decreased physical activity and ultimately affect the patient's oral hygiene performance. Thus, periodontal manifestations are presented as gingival bleeding and gingivitis.

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Background and Aim: Soft tissue condition around dental implant is an essential part for long term healthy and esthetic outcome. The aim of this study was to compare soft tissue dimensions between implant supported single  tooth replacement and the contra-lateral natural tooth.

Materials and Methods: This retrospective study was performed on dentate patients treated with anterior single  tooth implant at least 1 year ago. Of twenty eight, fourteen patients had been treated with one stasge method and others with two stage method. Biologic width (BW), papilla index (PI), and mucosal thickness (MT) were evaluated around implants and contra-lateral teeth clinically and compared with each other. The Wilcoxon test, Mann-Whitney test, and Student pair t-test were used to assess the differences between one stasge and two stage implants, and implant and tooth groups.

Results: The mean BW around one stasge implants, two stage implants, and contra-lateral teeth were 1.42±0.48 mm, 1.67±0.48 mm, and 1.47±0.60 mm, respectively. The mean PI adjacent to one stasge implants, Two stage implants, and contra-lateral teeth were 2.50±0.52, 2.53±0.55, and 2.72±0.47, correspondingly. The mean MT around one stasge implants, two stage implants, and contra-lateral teeth were 3.10±0.48, 3.09±0.75, and 2.57±0.88, respectively. There was no statistically significant difference among one stasge implants, two stage implants, and contra-lateral teeth with regard to measured variables.

Conclusion: Based on the results of this investigation, in standard condition, it seems that there is no noticeable difference in indicators of biologic width, papilla index, and mucosal thickness around one stasge implants, two stage implants, and contra-lateral teeth.

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Background and Aims: Nowadays reconstruction of alveolar defects has become one of dentists' problems especially in areas which are going to get dental implants. Inorganic bovine bone mineral (Bio-Oss) is one of the most popular graft materials that acts as a structure for migration of osteoblasts. If migration, proliferation, and differentiation of osteoblasts can be promoted by a material, it would be possible to reconstruct more amount of bone in a shorter period of time. Milk contains vital proteins that regulate bone growth. One of these important proteins is lactoferrin. The aim of this study was to examine the effect of added bovine lactoferrin to Bio-Oss on osteogenesis.
Materials and Methods: Two doses of 50 and 500 µg/ml of lactoferrin were prepared. Ten New Zealand white rabbits were selected for this study. Four 6-mm symmetrical detects were created in each rabbit's calvarium. Two of these sites were filled with Bio-Oss that was wetted with two doses of lactoferrin. Third detect was filled with Bio-Oss alone and the forth one was left empty as control group. After 4 weeks histologic and histomorphometric analysis was performed.
Result: There was no sign of obvious inflammation in any of four groups. Also there was no difference among four groups in terms of vitality, type of new bone, and foreign body reaction. However, amount of bone formation in control group was significantly lower compared with the other 3 groups. Although lactoferrin containing groups showed little increase in bone formation especially in higher concentration, there was not statistically significant difference among the three test groups. Amount of remaining biomaterial also was lower in lactoferrin containing groups compared with the Bio-Oss group but the differences were not significant.
Conclusion: Although there was no significant difference among the test groups, it seems that the added lactoferrin increases bone formation. Considering the limitations of this study, more studies are needed in different concentrations of lactoferrin and different healing periods. Furthermore, because of possible washout of the lactoferrin from the defects, it would be helpful to find and evaluate a proper carrier agent for lactoferrin to see its real effects.

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  Background and Aims: The increase in the number of complex implant cases has drawn the attention of researchers toward materials having bone regeneration promoting ability. Socket preservation and bone graft are recommended to minimize bone resorption. The aim of this study was to evaluate a kind of xenograft collagenic bone (osteo biol gen_oss) in socket regeneration.

  Materials and Methods: This randomized clinical trial was performed in 12 cases (6 in test and 6 in control groups) with two hopeless teeth. After tooth extraction, in test group, graft material was put in sockets but in the control group the socket was healed naturally. Three months later, during implant placement the specimens from both sites were sent to a pathologist for histologic and histomorphometric evaluations. Data were analyzed using Mc Nemar and Wilcoxan sigh rank test (α=0.05).

  Results: There were no significant differences between two groups in foreign body reaction, inflammation, bone vitality and percentage of bone gain. Average percentage of residual graft in test site was 6.73±1.43.

  Conclusion: Osteobiol gen_oss xenograft is an appropriate biocompatible osteoconductive material that promotes bone regeneration at 3 months following socket preservation in human extraction sockets.

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  Background and Aims : Free gingival graft is one of the most predictable procedures for gingival augmentation, but patient’s discomfort and pain during healing period of palatal donor site is a significant concern. The aim of this study was to evaluate the effect of 660nm low power laser on pain and healing in palatal donor sites.

  Materials and Methods: The present split mouth randomized controlled clinical trial was performed in 12 patients at the department of periodontics of Tehran University of Medical Sciences. Patients’ allocation was done by balanced block randomization (laser group and placebo group). In laser test group (wave length: 660 nm, power: 200mW, time of irradiation: 32s) was applied immediately post-surgery and in day 1, 2, 4 and 7 after that. In the control group, laser application was done with off power mode. Evaluation of epithelialization and healing was done with H₂O₂ and photograph. The number of palliative pills and bleeding was recorded. Wilcoxon test was used to analyze healing during the study. Patient’s pain during study was analyzed using repeated measure ANOVA. Mc Nemar test was used to analyze bleeding. Level of statistical significance was set at 0.05.

  Results: Laser group showed better epithelialization (P=0.02) and healing (P=0.01) in day 14 after surgery and showed better epithelialization in day 21(P=0.05). No statistically differences were observed between laser group and control group in terms of bleeding and medication (P=0.51), (P=1).

  Conclusion: According to the results of this study, the low power laser can promote palatal wound healing during the second and third week after free gingival graft procedures.