Granulocyte elastase in gingival crevicular fluid: improved monitoring of the site-specific response to treatment in patients with destructive periodontitis

Abstract In 13 patients with severe destructive periodontitis. the response to periodontal therapy was estimated by granulocyte elastase level in gingival crevicular fluid (GCF). 62 sites were classified according to changes of probing depths (PD) and quantitative bone height (BH%) before and after 5–year regular maintenance treatment: (i) 17 consistently healthy sites with no changes of PD and BH%; (ii) 6 initially healthy sites with deterioration in PD and BH%; (iii) 14 diseased sites with improvement in PD and BH%; (iv) 25 diseased sites with no improvement in PD and BH%. GCF was collected by an intracrevicular washing system. The released elastase in the supernatants (EA-S) and the cell-bound elastase in the pellets (EA-P) were determined with a low molecular weight substrate specific for granulocyte elastase. The ratio of EA-S and EA-P (S/P-ratio) was used as a relative measure of elastase released by the granulocytes present. The sites classified as diseased with no improvement or initially healthy but deteriorating, had significantly higher EA-S, EA-P and S/P-ratios than the consistently healthy sites or diseased but improving sites (p < 0.01). Both EA-S and S/P-ratio showed strongly positive correlations with the current levels of gingival inflammation and periodontal destruction (p < 0.001). The present study suggests that increased elastase level is associated with disease progression, and may be used to monitor the response to longitudinal maintenance therapy.     

正畸钢丝冠内固定治疗磨牙纵折的应用

目的:改进磨牙纵折保留治疗的固定方法.方法:对56颗磨牙纵折采用正畸钢丝冠内固定、牙体牙髓治疗加全冠修复的综合治疗,保留患牙.结果:56颗磨牙纵折成功49颗,失败7颗,有效率为87.5%.结论:在磨牙纵折的保留治疗中,正畸钢丝冠内固定是一种较佳的固定方法.     

The effect of porcine skin and autogenous epithelial grafts on the contraction of experimental oral wounds

Autogenous oral mucosa and skin grafts have been used clinically in vestibuloplasty to limit sulcus regression. However, these procedures require an additional surgical site and therefore increase morbidity. This study was designed to determine whether fresh porcine skin grafts would be as effective as skin or palatal mucosal grafts for controlling oral wound contraction. Standard sized experimental wounds were produced in dogs and, after grafting, were studied grossly and histologically for five to 60 days. All of the grafted sites showed less contraction than the control wounds, which were allowed to heal by secondary epithelialization. These findings suggest that porcine skin could serve as an effective biologic oral dressing following vestibuloplasty.     

正畸移动狗乳磨牙后其恒牙胚牙周组织 CSF-1及TGF-β1的表达及意义

目的：研究狗乳牙正畸移动后其恒牙胚才周组织中集落刺激因子(CSF-1)及转化生长因子-β1(TGF-β1)的表达．探讨乳牙移动后其恒牙胚改变的机制。方法：取狗下颌第二乳磨牙正畸移动后14d的组织标本，用免疫组织化学染色技术观察TGF-β1和CSF-1在恒牙胚牙囊、牙周才槽骨组织中的表达。结果：TGF-β1和CSF-1的染色在乳磨牙牙根的远中牙周膜和牙槽骨中以及恒牙胚的远中牙囊和牙槽骨中的表达明显减弱，在乳磨牙牙根的近中牙周膜和牙槽骨中以及恒牙胚的近中牙囊和牙槽骨中的表达明显增强。结论：狗乳牙正畸移动后其恒牙胚牙周组织也发生骨改建。     

小鼠牙胚发育过程中collagenⅠ/Ⅲ的表达分布

目的:探讨collagenⅠ、Ⅲ在Balb/c小鼠牙胚发育各期的时间和空间分布特点,及两者在牙齿发育矿化中的作用。方法:用免疫组化方法检测小鼠牙胚发育各期collagenⅠ、Ⅲ的表达、分布。结果:collagenⅢ:出生前E13d小鼠牙胚蕾状期:口腔上皮细胞阳性表达( );E14~17d帽状期:口腔上皮细胞、成釉器星网层细胞表达弱阳性;E18~19d和出生后P1d钟状期与分化期:口腔上皮细胞、成釉器星网层细胞、牙乳头细胞、牙囊细胞表达阳性( );出生后P2~10d牙冠发育成熟期:成釉细胞、釉基质、成牙本质细胞、前期牙本质、牙乳头细胞、牙囊细胞、牙髓组织等均表达阳性( );P10~30d牙根发育成熟期:除上述细胞成分外,上皮根鞘、根周及根尖牙槽骨、牙骨质和牙周膜表达强阳性( )。collagenⅠ:在蕾状期无表达;帽状期:口腔上皮细胞、成釉器星网层细胞表达阳性;钟状期与分化期:口腔上皮细胞、成釉器星网层细胞、牙乳头细胞、牙囊细胞表达阳性;牙冠和牙根发育期:其分布和表达类似于collagenⅢ。结论:鉴于collagenⅠ、Ⅲ的表达和分布,表明它们均参与了牙胚和牙体硬组织的发育形成,但似乎cllagenⅢ的作用比collagenⅠ更为广泛。     

Effect of finish line variants on marginal accuracy and fracture strength of ceramic optimized polymer/fiber-reinforced composite crowns

STATEMENT OF PROBLEM: Ceramic optimized polymer (Ceromer)/fiber-reinforced composite (FRC) crowns have been promoted as alternatives to conventional crowns. However, little is known regarding the ideal tooth preparation for this type of crown. PURPOSE: This in vitro study evaluated the marginal adaptation and fracture strength of ceromer/FRC crowns with respect to the various types of finish lines. MATERIAL AND METHODS: Four metal dies with different finish lines (0.9-mm chamfer, 1.2-mm chamfer, 1.2-mm rounded shoulder, and 1.2-mm shoulder) were prepared. Forty (10 for each finish line) Targis/Vectris crowns were fabricated on duplicated base metal alloy dies. The restorations were stereoscopically evaluated at 56 points along the entire circumferential margin for measuring the margin adaptation before and after cementation with a resin luting agent. The specimens were then compressively loaded to failure using a universal testing machine. The marginal adaptation (microm) was analyzed with the Kruskal-Wallis test and post-hoc Dunnett test (alpha=.05). The fracture load (N) was analyzed with a 1-way analysis of the variance and the Scheffe adjustment (alpha=.05). The fractured surfaces of the crowns were examined with a scanning electron microscope to determine the mode of fracture. RESULTS: The marginal adaptation of crowns with a shoulder finish line was significantly better than crowns with a chamfer finish line before and after cementation (P<.001). The increased marginal gap after cementation was the lowest in the 1.2-mm rounded shoulder group. The fracture strength of the crowns with the 0.9-mm chamfer and crowns with 1.2-mm chamfer was significantly greater than those of the crowns with the 1.2-mm shoulder or rounded shoulder (P=.011, P=.049, respectively). The mean fracture load of all crowns, regardless of the finish line design, was 1646 N. The fractured surface of the crown revealed adhesive failure and 3 types of cohesive failure (fracture of the Targis and Vectris, Targis fracture with a crack in the Vectris layer, and crushing without fracture). CONCLUSION: The marginal gaps were greater for the chamfer finish line specimens than in the shoulder finish line specimens. However, the fracture strength of the chamfer finish line specimens was greater than that of the shoulder finish line specimens.     

Education of dentists in China

China is geographically located in the east of Asia and its population exceeds 1.3 billion. An understanding of dental education in China is thus of interest. However, as there is little published information on this topic, this paper provides information about China regarding its dental history, dental school system including curriculum and dental licensure. High school graduates take a nationwide entrance examination to apply for dental school, of which there are more than 50 in China. A five year dental education leads to the BDS degree. Dental school graduates must then pass the nationwide licensure examination to practise dentistry. Currently, there are not adequate numbers of dentists to provide the necessary oral health care for people living outside metropolitan areas.     

Zygomaticomandibularis muscle

The aim of this study was to elucidate the precise anatomy of the zygomaticomandibularis muscle through cadaveric dissection and magnetic resonance imaging (MRI). Five fresh human cadavers and 10 fixed cadavers were dissected. Nine preserved human cadavers were used for the MRI study. Four volunteers took MRIs of their head as well. Zygomaticomandibularis muscle was found in all the cadaveric specimens. It is a fan shaped muscle. The length of the muscle is 25.1 +/- 4.6 mm, and the width at the zygomatic arch is 16.6 +/- 4.2 mm. The thickness is approximately 4.8 +/- 1.9 mm. It originates from the deep layer of the deep temporal fascia approximately 1 cm above the zygomatic arch and is inserted into the superior border and outer surface of the mandible between the coronoid process and mandibular notch. The deepest layer of the masseter muscle covers the lateral surface of zygomaticomandibularis. We believe that this muscle functions as coordinator of the temporalis and masseter in mammals with strong masticatory power but is a degraded or rudimentary muscle in humans.     

The prevalence of scrotal tongue and geographic tongue in 70,359 Israeli schoolchildren

abstract The prevalence of scrotal and geographic tongue among 70,359 Israeli schoolchildren was examined according to age, sex and father's country of birth. Scrotal tongue was observed in 1.96 % of the population, but increased with age from 0.60 % at 7 years to 3.76 % at 12–18 years. Males had a significantly higher prevalence. There were significant differences in the prevalence among the different population groups examined, in that the Ashkenazi had a higher prevalence (2.17 %) than both the non-Ashkenazi (1.93 %) and the Israeli (1.70%). Prevalence of geographic tongue was 1.14% and was not associated with age. Males had a significantly higher prevalence. The differences between the population groups were significant. A highly significant association was found in the occurrence of scrotal and geographic tongue.