Transforming growth factor-beta 1 (TGF-beta 1) expression in normal healthy pulps and in those with irreversible pulpitis

AIM: To evaluate the Transforming Growth Factor-beta 1 (TGF-beta 1) expression in normal healthy pulps and in those with irreversible pulpitis. METHODOLOGY: Twenty-three normal, healthy pulps were removed from mandibular third molars, and 20 pulps were retrieved from teeth with irreversible pulpitis. TGF-beta 1 was evaluated in the odontoblastic and subodontoblastic layers, in the stromal cells (fibroblasts), and in the blood vessels. TGF-beta 1 expression was determined by evaluating 500 cells in the odontoblastic and subodontoblastic layers and 500 fibroblasts in the stroma for each specimen, and counting the number of positive cells. The number of the positive vessels was evaluated in 10 high power fields (HPF). In almost all cases, the cellular positivity was cytoplasmatic. Statistical analysis was performed using Mann-Whitney U- and Student's t-tests. RESULTS: A higher expression of TGF-beta 1 was found in the odontoblastic-subodontoblastic layer of the irreversible pulpitis specimens; this difference was statistically significant (P = 0.0002). No statistically significant difference was observed between the two groups in TGF-beta 1 expression in the stromal cells (P = 0.54) or in the vascular component (P = 0.94). CONCLUSIONS: The higher and statistically significant expression of TGF-beta 1 found in the odontoblastic-subodontoblastic layer of irreversible pulpitis specimens may indicate a role for TGF-beta 1 in the dentinal repair processes after pulp inflammation.     

Patterns of antifungal prescribing in general dental practice

OBJECTIVE: To examine the current practice of antifungal prescribing by GDPs in the United Kingdom.Design A postal questionnaire circulated to a random selection of 400 dentists. OUTCOME MEASURES: The questionnaires were analysed and the responses expressed as absolute and relative frequencies. RESULTS: Responses to the questionnaire were received from 297 (74.3%) GDPs. Nystatin was the most popular choice of antifungal agent that GDPs would use, followed by miconazole, amphotericin B and fluconazole. The likelihood of use of miconazole was positively linked to recent date of graduation. Lack of knowledge regarding contraindications and problems with azole antibiotics was found in a significant minority of practitioners (36%). CONCLUSIONS: The present study indicates that azole antifungal agents (especially miconazole) are becoming more widely used by GDPs, but that knowledge regarding potential problems with their use is sub-optimal. Nystatin remains the most popular choice of antifungal agent.     

Prevalence, phenotype and genotype of oral enterococci

This study investigated the prevalence, phenotype and genotype of oral enterococci. Enterococci were detected in oral rinse samples from 11% of 100 patients receiving endodontic treatment and 1% of 100 dental students with no history of endodontic treatment ( P  = 0.0027). All enterococcal isolates were identified as Enterococcus faecalis . Viable counts ranged from 1 × 10 to 6 × 10³ colony forming units per mL of oral rinse sample. Potential virulence traits expressed by oral E. faecalis strains included production of hemolysin ( n  = 4) and gelatinase ( n  = 4), and response to pheromones in E. faecalis culture filtrate ( n  = 1). Six strains produced bacteriocin. All strains were susceptible to ampicillin, benzylpenicillin, gentamicin and vancomycin. There was no evidence of metal-ion resistance. One isolate produced hemolysin, gelatinase and bacteriocin, was resistant to several antibiotics, and responded to the pheromone cPD1. Pulsed-field gel electrophoresis and plasmid analysis showed that oral E. faecalis exhibited widespread genetic polymorphism, with plasmids detected in seven strains.     

Versorgung von Jochbeinfrakturen über einen transkonjunktivalen Zugang mit lateraler Kanthotomie unter Schonung des lateralen Lidbandes

Introduction

This study reports on a modified approach to treat zygomatic fracture. For the surgical approach, a transconjunctival incision and, instead of a lateral canthotomy, a superficial incision of the skin and subcutaneous tissue was used, preserving the lateral ligament. The results are compared with those of previous techniques, especially the subciliary incision.

Patients

In a prospective study, 30 patients (9 females and 21 males, mean age 32.1 years) with zygomatic fractures were operated using this approach. Mean follow-up time was 6 months after removal of the plates. Fractures were caused by trauma due to fighting, bicycle falls, or sport accidents. Follow-up radiographs were used to evaluate the position of the zygoma after reduction and rigid fixation.

Results

Reduction and rigid fixation of the fractures were possible to perform in all cases. The access to the orbital floor and the exposure of the inferior and lateral rim were satisfactory and an additional latero-orbital cut was not necessary. The disadvantage of the complete incision of the lateral ligament with the necessity of intraoperative refixation and possible ectropium of the eyelid could be avoided. Injuries or infections of the cornea or the bulbus did not occur. Postoperative complications such as scar formation resulting in entropium or ectropium were not seen.

Conclusion

These results show that the transconjunctival approach with lateral superficial incision preserving the lateral ligament for treatment of zygomatic fractures is satisfactory in all cases of rigid fixation of both inferior and lateral rims. Because of its esthetic and functional advantages this approach has become standard in our department.     

Biologic outcome of single-implant restorations as tooth replacements: a long-term follow-up study

Background: The replacement of a single tooth or several teeth by means of single‐implant restorations is an increasingly used method that needs long‐term validation. Purpose: The goal of this study was to evaluate the outcome of single‐implant restorations by means of fixed restorations and to define the prognosis through marginal bone level estimations. Materials and Methods: From November 1986 to June 1998, 270 Brånemark implants (215 in the upper jaw) were installed in 219 patients (106 males). Both anterior and posterior sites were involved. Of the 263 single restorations, 28 were placed in private dental offices. The patients were followed until June 1999. Results: Twelve implants failed before or at abutment connection or within 6 months afterward. Only four implants failed later. The cumulative success rates were 93% for the implants and 96.5% for the restorations over a period of 11 years. The marginal bone loss during the first 6 months after abutment connection reached 0.71 mm and then dropped to 0.036 mm annually over a period of 10 years. Conclusions: Single‐implant restorations (Brånemark System) are a reliable treatment with a good long‐term prognosis. Failures were concentrated during the healing period and early loading phase.     

Evaluations of the interface between amalgam and dentin with a single component dentin bonding system

The purpose of this scanning electron microscope study was to observe the dentin-amalgam interface after utilizing a standard restorative liner and a single-component dentin adhesive. Continuous interface gaps of over 15 mu were observed in specimens containing no lining and Copal varnish. Discontinuous 5 microns gaps were observed in specimens treated with PQ1. Additionally, specimens treated with PQ1 exhibited resin interpenetration into the dentin surfaces.     

The effect of Nd:YAG pulse duration on dentine crater depth

OBJECTIVES: The effect of alteration of laser parameters on laser-dentine interaction, in particular the effect of pulse duration, has not been well documented. The aim of this in vitro study was to determine the effect on dentine crater depth of Nd:YAG laser pulse duration, and total delivered energy, dentine site and the presence or absence of dye. METHODS: Ninety-six sound third molars were extracted and sectioned transversely to provide 192 upper and lower cut surfaces. The upper surfaces were painted with a layer of dye (IR5) suitable for absorption at 1064 nm. The specimens were divided into 16 sub-groups and exposed to two Nd:YAG lasers; one of pulse duration 7 ms and the second of pulse duration 35 ps. Both lasers operated in a non-contact mode (spot diameter 165 microm) with repetition rates of 10.5 and 10 Hz, respectively. Four total energies (2.28, 2.64, 3.6, 4.2 J) were delivered to eight dyed and eight undyed sub-groups. Eight outer and five inner sites were irradiated on each specimen. Dentine crater depth was measured five times using a Reflex Microscope and a three-dimensional centre of gravity derived. An upper and lower specimen were taken from each sub-group and viewed under a SEM. RESULTS: ANOVA and multiple regression analysis were applied and the following factors were found to have a statistically significant effect on crater depth (p<0.0001): total delivered energy, pulse duration and inner/outer location. CONCLUSIONS: Increasing energy and pulse duration produced deeper craters. Similarly inner dentine sites produced deeper crater depths. Only craters produced at the ms pulse duration were carbonised. It would appear that laser-dentine interaction has a non-thermal component at picosecond pulse duration.     

Influence of cigarette filters on the risk of developing oral leukoplakia in a Kenyan population

OBJECTIVE: To determine the influence of cigarette filters and the effect of smoking Kiraiku (home processed, hand rolled tobacco) on the risk of developing oral leukoplakia among cigarette smokers. DESIGN: Case control using population-based study groups in a Kenyan rural community. MATERIALS AND METHODS: 85 cases and 141 controls identified in a cross-section house-to-house screening of subjects aged 15 years and over and matched for sex, age (+/- 3 years) and cluster origin were compared for their use of filter and non-filter cigarettes as well as their history of smoking Kiraiku. RESULTS: The relative risk (RR) of oral leukoplakia was 9.1 (95% confidence intervals (CI) = 4.1-20.2) in smokers of filter cigarettes and 9.8 (95% CI = 2.3-47.0) in smokers of non-filter cigarettes. The RR in the latter compared to the former was 1.1 and was not statistically significant. Regarding the influence of smoking Kiraiku, the RR of this lesion was 29.3 in smokers of both Kiraiku and filter cigarettes and 17.3 in smokers of both Kiraiku and non-filter cigarettes. CONCLUSIONS: There was no statistically significant difference between the influence of filter and non-filter cigarettes on the risk of developing oral leukoplakia. The effect of Kiraiku on the risk of this lesion was stronger in filter than in non-filter cigarettes. However, the confounding effect of tobacco dose response parameters could not be ruled out.     

A systematic review of the effectiveness of antifungal drugs for the prevention and treatment of oropharyngeal candidiasis in HIV-positive patients

OBJECTIVE: A systematic review of randomized clinical trials published between 1966 and April 2000 was undertaken to determine the strength of evidence for the effectiveness of antifungal drugs (nystatin, clotrimazole, amphotericin B, fluconazole, ketoconazole, and itraconazole) to prevent and treat oral candidiasis in human immunodeficiency virus-positive patients. STUDY DESIGN: An automated database search identified 366 articles. Six met inclusion and exclusion criteria with respect to prophylaxis; 12 met criteria for treatment of oral candidiasis. RESULTS: The evidence for the prophylactic efficacy of fluconazole is good, although insufficient to draw conclusions about the other antifungals. Evidence for treatment effectiveness is insufficient for amphotericin B but good for nystatin, clotrimazole, fluconazole, ketoconazole, and itraconazole. CONCLUSION: Suggestions for strengthening the evidence base include the following: use of larger, more well-defined groups; control for immunologic status, viral load, history of oral candidiasis, past exposure to antifungals, baseline oral Candida carriage, drug interactions, and antiretroviral therapy; and consistent use of compliance monitors, fungal speciation, and susceptibility testing.