不同离体时间和保存液对犬离体牙牙周膜细胞活力影响的实验研究

目的:探讨完全脱位牙不同离体时间和保存液对牙周膜细胞活力的影响。方法:麻醉拔除犬牙35个,首先将20个牙随机分为5组,分别为室温干燥放置0、30、60、120、240 min组,另15个牙室温干燥放置30 min后,随机分为3组,分别放入牛奶、HBSS液,100 g/L蜂胶液中浸泡2 h。各组处理完成后,采用全牙消化法获得牙周膜细胞,并通过4 g/L台盼蓝染色法检测各组牙周膜活细胞数和存活率。结果:室温干燥放置30、60、120、240 min后,牙周膜细胞存活率依次为33.6%、23.6%、18.5%、0.8%,而0 min的牙周膜细胞存活率可达95.5%。拔后30 min,经牛奶、HBSS液和100 g/L蜂胶液中保存2 h后,牙周膜细胞均有活力,其细胞存活率大小依次为100 g/L蜂胶液、HBSS液和牛奶,其中100 g/L蜂胶液与HBSS液相比无统计学差异(P>0.05),但与牛奶组相比,均有统计学差异(P<0.05)。结论:随着离体时间延长,完全脱位牙根面牙周膜细胞活力明显下降。100 g/L蜂胶液和HBSS液保存犬牙牙周膜细胞活力优于牛奶液。     

Study of the effectiveness of propolis extract as a storage medium for avulsed teeth

Abstract – The purpose of the present study was to evaluate the efficacy of propolis extract in maintaining the viability of human periodontal ligament (PDL) cells, and to radiographically analyze tooth replantation and the adjacent periodontium in dogs after storage in this extract. Human PDL cells were incubated with the experimental media propolis, milk, saliva, Hank’s balanced salt solution (HBSS), and Dulbecco’s modified Eagles medium (DMEM, positive controls), and distilled water (negative control). Cell viability was determined 0, 1, 3, 6, 12, and 24 h later by colorimetric MTT assay. Thirty incisors from dogs were divided into two storage time blocks (1 and 3 h) and were maintained in the experimental media. HBSS served as a positive control, and dry teeth (on gauze) as a negative control. The replanted teeth were radiographed once per month for 6 months. The radiographic images were standardized by the shortening/lengthening factor, and were both qualitatively and quantitatively analyzed. The in vitro results showed that the efficacy of propolis in maintaining functional viability of PDL cells was similar to that of milk. Propolis and milk were significantly better than controls from the 6‐h time period. The in vivo results showed that teeth maintained in propolis medium exhibited replacement resorption with significant reduction in tooth length, similar to teeth maintained in saliva and dried teeth. This resorption was less intense with the 3‐h storage time than the 1‐h storage time. Conditions close to normal were found in teeth maintained in milk, similar to the HBSS control. Therefore, although propolis was effective in maintaining the viability of human PDL cells, resorption of the tooth replantation in dogs occurred under these experimental conditions.     

Assessment of post-traumatic PDL cells viability by a novel collagenase assay

Abstract – Both length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis for replanted teeth. Numerous studies have examined various media in an attempt to determine the ideal material for storage of the avulsed tooth. The purpose of this study was to compare the number of viable periodontium ligament (PDL) cells in different storage media using a collagenase assay. Thirty-three freshly extracted human teeth were divided into four experimental and two control groups. The positive and negative controls corresponded to 0 min and an 8-h dry time, respectively. The experimental teeth were stored dry for 30 min and then immersed in one of four media (Hank's balanced salt solution (HBSS), milk, saline, water) for 45 min. The teeth were then treated with dispase grade II and collagenase for 30 min. The number of viable and nonviable PDL cells was counted with a hemocytometer and analyzed. An anova demonstrated no statistically significant differences in the viability of PDL cells among saline, HBSS and milk. Within the parameters of this study, it appears that milk or saline is an equally viable alternative to HBSS for storage of avulsed teeth.     

A quantitative analysis of Propolis: a promising new storage media following avulsion

Abstract –  Both length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis of replanted teeth. Numerous studies have examined various media in an attempt to determine the ideal material for storage of the avulsed tooth. The purpose of this study was to use a Collagenase–Dispase assay to investigate the potential of a new storage media, Propolis, in maintaining viable periodontal ligament (PDL) cells on simulated avulsed teeth. Seventy freshly extracted human teeth were divided into five experimental groups and two control groups. The positive and negative controls corresponded to 0-min and an 8-h dry time, respectively. The experimental teeth were stored dry for 30 min and then immersed in one of the five media (Hank's balanced salt solution (HBSS), milk, saline, Propolis 50%, and Propolis 100% for 45 min). The teeth were then treated with dispase grade II and collagenase for 30 min. The number of viable PDL cells were counted with a hemocytometer and analyzed. Statistical analysis demonstrated that both Propolis groups kept significantly more PDL cells viable compared to either milk, saline, or HBSS. Within the parameters of this study, it appears that Propolis may be a better alternative to HBSS, milk, or saline in terms of maintaining PDL cell viability after avulsion and storage.     

Viability of fibroblasts in a novel probiotic storage media

Abstract – A number of storage media have been investigated as to their ability to maintain the viability of the periodontal ligament (PDL) cells and thus to permit longer extra‐alveolar periods prior to replantation of avulsed teeth. The aim of the present in vitro study was to evaluate the number of viable PDL cells of avulsed teeth treated by Hank’s Balanced Salt Solutions (HBSS), saline, a novel probiotic solution and milk. Thirty‐six freshly extracted single‐rooted human teeth with closed apices were divided into one of the four experimental groups and two control groups (N = 6 each). The positive and negative controls corresponded to 0 min and an 8‐h dry time respectively. Following extraction, the coronal 3 mm of PDL tissue was scraped with a #15 scalpel to remove cells that might have been damaged. The experimental teeth were dried for 30 min followed by a 45 min immersion in one of the four experimental media. Each experimental tooth, after drying and soaking, was incubated for 30 min with a 2.5 ml solution of 0.2 mg ml^?1 of collagenase CLS II and a 2.4 mg ml^?1 solution of dispase grade II in phosphate buffer saline (PBS). The cells were then labelled with 0.4% Trypan blue for determination of viability. The teeth stored in positive control demonstrated the highest number of viable PDL cells followed in rank order by HBSS, saline, Lactobacillus reuteri solution and milk. There was no significant difference in the number of viable PDL cells between HBSS, milk, L. reuteri solution and saline. Within the parameters of this study, it appears that probiotic may be able to maintain PDL cell viability as HBSS, milk, or saline.     

Effect of soaking in Hank's balanced salt solution or milk on PDL cell viability of dry stored human teeth

Abstract— This study was designed to evaluate the effect of soaking in either Hank's balanced salt solution (HBSS) or milk on peri⁻odontal ligament (PDL) cell viability in avulsed teeth. Dry storage times of 30, 60, and 90 min were evaluated. PDL cell viability was determined after removal of the cells from the root surfaces of extracted teeth using a modification of the procedure described by Nakashima (Arch Oral Biol 1991;36:655–63). After trypsinization and subsequent treatment in collagenase, the cells were stained with trypan blue, and viable and non-viable cells were counted using a hemocytometer and converted to percentages for statistical comparison. The results of this study demonstrated no significant difference in the number of viable cells with or without soaking in HBSS or milk at any of the dry storage times. In addition, there was no significant difference in PDL cell viability between the 30-and the 60-min dry periods. Although the soaking procedure had no obvious negative consequence, no simcant improvement in PDL cell viability by the addition of this step was demonstrated under the conditions of this study.     

Pedialyte Promotes Periodontal Ligament Cell Survival and Motility

IntroductionThe search still continues to find the best storage media for avulsed teeth. Unfortunately, some of the recommended storage solutions are not commonly found in households or do not preserve the periodontal ligament (PDL) cells long-term. The purpose of the present study was to determine whether Pedialyte is a viable alternative storage solution for avulsed teeth by assessing its ability to preserve human PDL cell viability.MethodsHuman PDL cells were exposed to 6 different storage solutions (minimal essential medium [MEMα], Hank's balanced salt solution [HBSS], non-fat milk, coconut water, Pedialyte, or tap water) for 2, 6, 24, or 48 hours at 4°C or 25°C. Cell viability was quantified immediately or 1 week after exposure. The effects of these storage solutions on PDL cell motility and bacterial proliferation were also examined. The results were statistically analyzed by analysis of variance.ResultsPedialyte at 4°C and 25°C showed significantly (P < .001) higher cell survival compared with water after all time intervals. No significant difference was noted between control (MEMα), HBSS, coconut water, and Pedialyte at 4°C after 2 hours. Cells stored in Pedialyte for 24 hours at 25°C and assayed 1 week later showed significantly higher cell survivability compared with milk. Pedialyte supported significantly less bacterial growth compared with non-fat milk and coconut water. No difference in cell motility was observed for cells stored for 24 hours in Pedialyte, MEMα, HBSS, milk, or coconut water.ConclusionsPedialyte is a viable alternative as a storage solution for avulsed teeth.     

Comparison of coconut water, propolis, HBSS, and milk on PDL cell survival

Coconut water is biologically pure and sterile, with a rich presence of amino acids, proteins, vitamins, and minerals. The purpose of this study was to use a collagenase-dispase assay to investigate the potential of a new storage medium, coconut water, in comparison with propolis, Hank's balanced salt solution (HBSS), and milk in maintaining viable periodontal ligament (PDL) cells on simulated avulsed teeth. Seventy freshly extracted human teeth were divided into 4 experimental groups and 2 control groups. The positive and negative controls corresponded to 0-minute and 8-hour dry times, respectively. The experimental teeth were stored dry for 30 minutes and then immersed in 1 of the 4 media (coconut water, propolis, HBSS, and milk). The teeth were then treated with dispase grade II and collagenase for 30 minutes. The number of viable PDL cells was counted with a hemocytometer and analyzed. Statistical analysis showed that coconut water kept significantly more PDL cells viable compared with propolis, HBSS, or milk. Coconut water can be used as a superior transport medium for avulsed teeth.     

Comparison of soymilk, powdered milk, Hank's balanced salt solution and tap water on periodontal ligament cell survival

The purpose of this study was to evaluate the ability of soymilk, powdered milk, and Hank's balanced salt solution (HBSS) to maintain human periodontal ligament (PDL) cell viability in vitro. PDL cells were obtained from extracted healthy third molars and cultured in Dulbecco's modified Eagles medium (DMEM). The cultures were exposed for 1, 2, 4, and 8 h to experimental solutions (tap water served as negative control and DMEM as positive control) at 37°C. The viable cells were then counted using the trypan blue exclusion technique. Data were analyzed by using one-way anova, post hoc Scheffe and two-way anova test. Statistical analysis showed that HBSS, powdered baby formula, and soymilk maintain cell viability equally well in different periods of times. Tap water cannot keep cells viable as well as other solutions. Soymilk and powdered baby formula can be recommended as suitable storage media for avulsed teeth for up to 8 h.     

The use of green tea extract as a storage medium for the avulsed tooth

Introduction

Green tea extract (GTE) has been reported to have remarkable anti-inflammatory, antioxidant, and anticarcinogenic effects and to prolong allograft survivals. The purpose of the present study is to investigate in vitro the efficacy of GTE as a storage medium for avulsed teeth. We estimated the possibility for storage medium by maintaining the viability of human periodontal ligament (PDL) cells.

Methods

Human PDL cells were cultured and stored in the following media: (1) Hank’s balanced salt solution (HBSS), (2) tap water, (3) milk, (4) GTE, and (5) commercial green tea. After 1, 3, 6, 12, and 24 hours, cells in different media were examined under the optical microscope, and their viabilities were analyzed by using a nucleocounter and 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethonyphenol)-2-(4-sulfophenyl)-2H-tetrazolium assay. The data were statistically analyzed by analysis of variance tests with post analysis using the Duncan method (P < .05).

Results

The result indicates that there was no difference in cell viability between GTE and HBSS media, whereas GTE showed higher cell viability than other media (P < .05).

Conclusions

Our study shows that the efficacy of GTE in maintaining the viability of human PDL cells is similar to that of HBSS and higher than that of milk. Therefore, we conclude that GTE could be a suitable, alternative storage medium for avulsed teeth.     

Effect of chlorophyllin on normothermic storage of human periodontal ligament cells

The purpose of the present study was to evaluate whether chlorophyllin could serve as an effective constituent of a storage medium to enhance the human periodontal ligament (PDL) cell viability.Freshly isolated PDL cells from premolars extracted from healthy people were stored at 37 degrees C for 6 h in various solutions: F-medium and Hank's balanced salt solution (HBSS), supplemented with chlorophyllin. From MTT viability assays, the highest cell viability was found in the PDL cells stored in HBSS supplemented with 500 nM chlorophyllin, and the chlorophyllin-treated cells showed a dose-dependent response to concentration. Additionally, the results from flow cytometry showed that 77 to 80% of the PDL cells were in the G0/G1 phases of the cell cycle, which suggested that most were in a stable stage.These result showed that HBSS, supplemented with chlorophyllin, may be a useful solution for preserving the viability of PDL cells.     

In vitro viability, mitogenicity and clonogenic capacity of periodontal ligament cells after storage in six different media

The choice of storage medium for preserving traumatically avulsed teeth is important for the success of future replantation. The objectives of this study were to evaluate the effectiveness of six different media: culture medium, alpha minimal essential medium (alpha-MEM), milk, Hank's balanced salt solution (HBSS), ViaSpan and conditioned medium (CM) to preserve cultured periodontal ligament fibroblasts (PDLF). Periodontal ligament fibroblasts were obtained from explants of human healthy extracted teeth. Plates with confluent PDLF were soaked in the various media for 2, 8 and 24 h at 4 degrees C. A control group was incubated with culture medium at 37 degrees C. After incubation, cell viability was determined by trypan blue exclusion test. Viable cells were then analyzed for mitogenic (with thymidine) and clonogenic capacity (by culturing one cell/well). Storage of PDLF up to 24 h decreased their vitality by only 2%-14%. Vitality of the PDLF after 2, 8 and 24 h was highest when stored in milk or HBSS (91%-97%) and lowest when stored in ViaSpan or CM (82%-93%). PDLF stored for 2-8 h in various media had a mitogenic capacity comparable to the control. However, increasing the storage period to 24 h decreased the mitogenicity of the cells by 3%-39%. The highest mitogenicity was found in PDLF stored in milk or HBSS and the lowest in CM or ViaSpan. The clonogenic capacity of the cells dropped by 38%-71% after 24 h and was the best indicator of the deteriorating effect of long storage. Milk and HBSS were the most effective in preserving the clonogenic capacity. Nevertheless, reduction in the viability, mitogenicity or clonogenic capacity was statistically significant in nearly all the tested media only after 24 h of incubation. In conclusion, HBSS and milk were the most effective media for preserving the viability, mitogenicity and clonogenic capacity after storage for up to 24 h at 4 degrees C.     

Storage media enhance osteoclastogenic potential of human periodontal ligament cells via RANKL‐independent signaling

Abstract – Background: Hank’s balanced salt solution (HBSS) and milk have gained wide acceptance as storage media for avulsed tooth. However, the effect of the media and storage time on the periodontal ligament (PDL) cells involvement in the development of root resorption is still unclear. The purpose of this study was to evaluate whether precultured PDL cells in HBSS, milk, or modified Eagle’s medium alpha (α‐MEM) would affect osteoclastogenesis. Materials and methods: PDL cells were precultured in HBSS, milk, or α‐MEM for 1 h or 6 h before being co‐cultured with RAW 264.7 cells for an additional 3 days for mRNA analysis and 11 days for osteoclastogenesis assay. Results: Cyclooxygenase‐2 (COX‐2) mRNA was detected immediately in PDL cells precultured in the three storage media. The expression was up‐regulated markedly in all co‐cultures when compared with RAW cells alone. As a result of the co‐culture, interleukin‐1β (IL‐1β) expression was detectable in both PDL and RAW cells. TRAP+ multinucleated, osteoclast‐like cells developed in all co‐cultures; the number of TRAP+ cells was highest (P < 0.05) in the co‐cultures that PDL cells precultured in milk for 6 h. The mRNA level of receptor activator of nuclear factor‐kappa B ligand (RANKL) was not detected in PDL cells. Osteoprotegerin (OPG) mRNA expression reduced with increased preculture time, but the difference was not significant (P > 0.05). Conclusions: PDL cells kept in the three storage media led to TRAP+ multinucleated, osteoclast‐like cells formation via RANKL‐independent signaling. The ability to induce osteoclastogenesis may be considered as one of the factors to evaluate the ability of storage medium to maintain PDL viability after tooth avulsion.     

In vitro viability, mitogenicity and clonogenic capacity of periodontal ligament cells after storage in six different media

Abstract— The choice of storage medium for preserving traumatic-ally avulsed teeth is important for the success of future replantation. The objectives of this study were to evaluate the effectiveness of six different media: culture medium, α minimal essential medium (αMEM), milk, Hank's balanced salt solution (HBSS), ViaSpan and conditioned medium (CM) to preserve cultured periodontal ligament fibroblasts (PDLF). Periodontal ligament fibroblasts were obtained from explants of human healthy extracted teeth. Plates with confluent PDLF were soaked in the various media for 2, 8 and 24 h at 4°C. A control group was incubated with culture medium at 37°C. After incubation, cell viability was determined by trypan blue exclusion test. Viable cells were then analyzed for mitogenic (with thymidine) and clonogenic capacity (by culturing one cell/well). Storage of PDLF up to 24 h decreased their vitality by only 2%-14%. Vitality of the PDLF after 2, 8 and 24 h was highest when stored in milk or HBSS (91%-97%) and lowest when stored in ViaSpan or CM (82%-93%). PDLF stored for 2–8 h in various media had a mitogenic capacity comparable to the control. However, increasing the storage period to 24 h decreased the mitogenicity of the cells by 3%-39%. The highest mitogenicity was found in PDLF stored in milk or HBSS and the lowest in CM or ViaSpan. The clonogenic capacity of the cells dropped by 38%-71% after 24 h and was the best indicator of the deteriorating effect of long storage. Milk and HBSS were the most effective in preserving the clonogenic capacity. Nevertheless, reduction in the viability, mitogenicity or clonogenic capacity was statistically significant in nearly all the tested media only after 24 h of incubation. In conclusion, HBSS and milk were the most effective media for preserving the viability, mitogenicity and clonogenic capacity after storage for up to 24 h at 4°C.     

A Quantitative Analysis of a Probiotic Storage Media for Avulsed Teeth

Aim

The aim of the present in vitro study was to investigate the potential of a storage medium, probiotic yogurt (Bifidibacterium animalis DN 173010) in comparison with Hank''s balanced salt solution (HBSS), saline and milk in maintaining viable periodontal ligament (PDL) cells on simulated avulsed teeth.

Materials and methods

Thirty-six freshly extracted single-rooted human teeth with closed apices were divided into six experimental groups (N=6). The teeth were extracted as atraumatically as possible and washed in sterile saline solution to eliminate residual blood. Following extractions, the coronal 3 mm of PDL tissues were scraped with a #15 scalpel to remove cells that may have been damaged. The positive and negative controls corresponded to 0 minutes and an 8-hour dry time, respectively. After extraction, the positive control teeth were immediately treated with dispase and collagenase. The negative control teeth were bench-dried for 8 h, with no follow-up storage solution time, and then placed in the dispase and collagenase. The number of viable protective least significant difference PDL cells were counted under a light microscope with a hemocytometer at 20× magnification and analyzed. Statistical analysis of the data was accomplished using Nonparametric ANOVA complemented by Kruskal-Wallis Test and Dunn''s Multiple Comparisons Test.

Results

Positive control was found to be significantly better than the others, there were statistically significant differences between positive control and other test groups (p=0.000). The teeth stored in positive control demonstrated the highest number of viable PDL cells followed in order by probiotic yogurt, HBSS, saline and milk.

Conclusion

Bifidibacterium animalis DN 173010 seems to be an alternative for the temporary storage of avulsed teeth, due to high number of viable PDL cells. Probiotics may be suitable transport media for avulsed teeth, but further research is warranted using the commercially available products.Key words: dental trauma, probiotic, storage media     

Which is the most recommended medium for the storage and transport of avulsed teeth? A systematic review

Background/Aims

A wide variety of materials has been researched for their use as potential storage media for avulsed teeth, but it is essential to recognize the medium most recommended for improvement of the prognosis of avulsed teeth. The aim of this systematic review was to identify the most recommended medium to store and transport avulsed teeth based on the survival of periodontal ligament (PDL) cells as determined by in vitro studies.

Methods

Only laboratory‐based experimental studies on PDL cells found on adult permanent teeth were included. Data were collected using PubMed, CINAHL plus (EBSCO host), and the Cochrane Library, along with Google Scholar and a hand search. The key terms employed were permutations of [avulsed permanent teeth* OR dental avulsion* OR knocked out teeth*] AND [storage media* OR transport media* OR biological transport* OR PDL cell viability* OR PDL cell survival*]. A customized data extraction pro forma was used to extract the data and to evaluate the quality and risk of bias.

Results

The initial search yielded 978 articles, but only 67 were selected. Milk was the most recommended individual medium followed by Hank's balanced salt solution. Among natural products other than milk, propolis and coconut water were most frequently recommended. Recommendations were based on maintenance of PDL cell viability followed by ease of availability, low cost, and long shelf life.

Conclusions

Natural products are more effective in maintaining the PDL cell viability compared to synthetic products. Some storage media recommendations were also based upon practical aspects. Although natural products other than milk have more recommendations as a group, milk is the most recommended storage medium individually, based not only on PDL cell viability, but also practical considerations.     

Viability of human periodontal ligament fibroblasts in tissue culture after exposure to different contact lens solutions

AIM: The viability of the periodontal ligament (PDL) cells is critical for successful healing of replanted avulsed teeth. Viability is primarily dependent on the duration of the extra-alveolar time and storage medium used to preserve teeth. Several storage media have been suggested but milk ranks highest. It would be desirable to evaluate other media as a suitable alternative for milk. The purpose of this study was to determine the viability of human PDL fibroblasts and their morphology after storage in different types of contact lens solutions. METHODS AND MATERIALS: PDL fibroblasts were cultured from a healthy extracted impacted human tooth and exposed to Bausch and Lomb (Renu), Ciba Vision (Titmus), and Alcon (Opti-free) contact lens solutions. Eagle's minimal essential medium served as control. The experiment was performed in plastic tissue culture clusters containing 24 wells. The PDL fibroblasts were grown in each well for three days. On the day of the experiment the culture medium was decanted, the cells were washed with phosphate buffered saline solution (PBS), and 1 ml of the tested solution was placed in each culture well. All tissue culture clusters were incubated at 37 degrees C in 5% CO2 and 95% air for one, four, and 24 hrs. At the end of the incubation period, the cells were fixed and prepared for scanning electron microscope (SEM) examination. RESULTS: The results indicated Renu and Opti-free solutions were superior to Titmus solution in terms of their capacity to maintain the viability and normal morphology of PDL fibroblasts. CONCLUSION: Contact lens solution is a good storage medium to maintain the viability of PDL fibroblasts for a short-term period.     

Survival of human periodontal ligament cells in media proposed for transport of avulsed teeth

Abstract –  Many solutions have been examined as possible storage media for avulsed teeth. In this report, human periodontal ligament (PDL) cells were exposed for 1 h to culture medium, milk, Hanks Balanced Salt Solution (HBSS), Soft Wear, Opti Free, and Solo Care contact lens solutions, Gatorade^®, and tap water, at room temperature and on ice. The number of viable cells was counted using the trypan blue exclusion technique, immediately after exposure (0 h) and at 24 and 48 h, to test the proliferative capacity of the cells after treatment. The results indicated that a significantly higher number of cells survived and proliferated when the exposures were performed at 0°C. Water had a detrimental effect on the cells, whereas culture medium and HBSS preserved significantly more viable cells than the other experimental solutions. Within the parameters of this study, it appears that HBSS is the optimal storage medium for avulsed teeth. Low-fat milk could serve as an alternative if ice is available. Contact lens solutions or Gatorade^® on ice could serve as short-term (1 h) storage media if the other solutions are not readily available.     

Effect of preservation media on proliferation and collagen biosynthesis of periodontal ligament fibroblasts

Abstract The viability of periodontal ligament (PDL) cells, which are responsible for the production of ligament proteins, is essential for clinical healing of replanted exarticulated teeth. Cultured human PDL fibroblast-like cells were used to study the effects of various transport media on cell proliferation, collagen synthesis and total protein synthesis. The PDL cells were obtained from intact premolars of a healthy young male patient by trypsinization and scraping the PDL tissue. Proliferation of the cells, the activity of prolyl 4-hydroxylase, total protein and collagen synthesis were studied after 60 min incubation in Dulbecco's Modified Eagle's Medium (DMEM), milk, saliva and tap water. Proliferation capacity was also investigated after prolonged incubation in milk. The results indicated that milk and saliva were superior to water in maintaining these cell functions, but as the saliva used in this study does not resemble that in the clinical situation, we recommend milk as a temporary storage medium for exarticulated teeth before replantation.     

不同处理条件对脱位牙牙周膜形态影响的扫描电镜观察

目的 观察不同方式处理的脱位牙牙周膜形态特点。方法 取临床拔除的牙根已发育完成的前磨牙,分别在空气中自然干燥放置1、2、4 h后,再以生理盐水或Hank′s平衡盐溶液(HBSS)浸泡处理0.5 h,制成扫描电镜标本,在扫描电镜下观察和比较牙颈部牙根表面牙周膜的形态特点。结果 脱位牙牙周膜表面形态随着干燥放置时间的增加其受损程度逐渐加重,经过保存液的处理,其牙周膜表面细胞和纤维的形态有了一定程度的恢复。HBSS处理组比生理盐水处理组牙周膜的形态恢复略好。结论 干燥放置的脱位牙在HBSS中浸泡,其牙周膜表面的细胞形态、胶原纤维的排列都优于生理盐水,这两种保存液都对干燥放置的脱位牙牙周膜的形态具有一定的恢复作用。?