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31.
Background: Surgery utilizing an enamel matrix protein derivative (EMD) or guided tissue regeneration (GTR) has been shown to promote periodontal regeneration.
Aim: To evaluate the 10-year results following treatment with EMD, GTR, EMD+GTR, and open flap debridement (OFD).
Material and Methods: Thirty-eight patients out of an initial group of 56 participants were treated with one of the four modalities. Results were evaluated before surgery, at 1 year, and at 10 years. Primary outcome variable was CAL change.
Results: Treatment with EMD yielded a mean CAL gain of 3.4±1.0 mm ( p <0.001) and 2.9±1.4 mm ( p <0.001) at 1 and 10 years, respectively. GTR resulted in a mean CAL gain of 3.2±1.4 ( p <0.001) at 1 year and 2.8±1.2 mm ( p <0.001) at 10 years. Mean CAL gain in the EMD+GTR group was of 3.3±1.1 mm ( p <0.001) and 2.9±1.2 mm ( p <0.001) at 1 and 10 years, respectively. Treatment with OFD demonstrated a mean CAL gain of 2.0±1.2 mm ( p <0.01) at 1 year and 1.8±1.1 mm ( p <0.01) at 10 years. Compared with OFD, the three regenerative treatments resulted in statistically significant ( p <0.05) higher CAL gain, at both 1 and 10 years. The CAL change between 1 and 10 years did not present statistically significant differences in any of the four groups.
Conclusion: The present results indicate that the clinical outcomes obtained with all four approaches can be maintained over a period of 10 years.  相似文献   
32.
King D 《British dental journal》2006,200(9):505; author reply 506-505; author reply 507
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35.
This investigation was conducted to determine whether primary herpetic gingivostomatitis may be responsible for those signs and symptoms commonly attributed to teething in infants. Twenty infants presenting with a parental diagnosis which indicated teething difficulty were included in this study (Group A). Twenty infants who were in no distress served as controls (Group B). Oral swab samples were obtained from each infant and then processed to ascertain the presence of herpes simplex virus (HSV). Each infant's temperature and oral status also were recorded. Nine subjects in Group A (45%) were positive for HSV. Of these nine, seven had elevated temperatures (less than 100 degrees F) and all had signs of oral infection of varying severity. Of the 11 subjects in Group A who were negative for HSV, five had elevated temperatures, but none showed evidence of oral infection. Subjects in Group B were all negative for HSV, elevated temperature, and signs of oral infection. Results of this study suggest that oral HSV infection should be included in the differential diagnosis of infants presenting with a parental diagnosis of teething difficulty.  相似文献   
36.

Objective

This study examined the effect of temperature on water sorption and solubility characteristics of four commercial dental adhesives. The null hypothesis tested was that temperature has no effect on the water sorption and solubility characteristics of these adhesives.

Methods

The tested materials were: three-step etch-and-rinse (All-Bond 2, AB), two-step etch-and-rinse (One-Step, OS), two-step self-etch (Clearfil SE Bond, SE) and one-step self-etch (Clearfil S3 Bond, S3) adhesives. Seven resin disks (6 mm in diameter × 1 mm in thickness) were prepared from each tested material and were stored in deionized water at 23 °C, 37 °C and 55 °C. Water sorption and solubility of the resin disks were measured before and after water immersion and desiccation following two consecutive sorption and desorption cycles. The water sorption and solubility values obtained were analyzed using two-way ANOVA and Tukey's multiple comparison tests. The relationships between maximum water sorption, solubility and kinetics of water diffusion with temperature were evaluated by means of Pearson correlation statistic.

Results

OS exhibited the highest water sorption and solubility values in the second sorption–desorption cycle at 55 °C (p < 0.001). This is followed by S3, SE and AB with no significant difference between SE and AB. Significant positive correlations were observed between maximum water sorption (r = 0.307, p < 0.01), solubility (r = 0.244, p < 0.05), water sorption (r = 0.651, p < 0.001) and desorption (r = 0.733, p < 0.001) diffusion coefficients (obtained using Fick's law of diffusion) with temperature in the second cycle.

Significance

High temperatures increased water sorption of simplified adhesives. Such water sorption may contribute to the failure of resin–dentin bonds.  相似文献   
37.
BACKGROUND: The purpose of the present study was to compare the healing of deep intrabony defects following treatment with an enamel matrix protein derivative (EMD) combined with either a natural bone mineral (NBM) or beta-tricalcium phosphate (beta-TCP). METHODS: Twenty-four patients with advanced periodontal disease, each of whom displayed one intrabony defect, were randomly treated with a combination of either EMD + NBM or EMD + beta-TCP. Clinical evaluation was performed at baseline and 1 year following therapy. RESULTS: No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the sites treated with EMD + NBM showed a reduction in mean probing depth (PD) from 7.9 +/- 1.0 mm to 3.2 +/- 0.6 mm and a change in mean clinical attachment level (CAL) from 8.8 +/- 1.1 mm to 4.5 +/- 0.6 mm (P < 0.001). In the group treated with EMD + beta-TCP, the mean PD was reduced from 7.8 +/- 1.2 mm to 3.2 +/- 0.9 mm, and the mean CAL changed from 8.8 +/- 1.2 mm to 4.7 +/- 1.2 mm (P < 0.001). In both groups, all sites gained at least 3 mm of CAL. CAL gains of 4 or 5 mm were measured in the majority of the cases (75%), irrespective of treatment modality. No statistically significant differences in terms of PD reductions and CAL gains were observed between the two groups. CONCLUSION: Within the limits of the present study, both therapies resulted in significant PD reductions and CAL gains 1 year after surgery.  相似文献   
38.
The aim of this double-blind, controlled crossover study was to evaluate the influence of food preservatives on in situ dental biofilm growth. Twenty-four volunteers wore appliances with six specimens each of bovine enamel to build up intra-oral biofilms. During three test cycles, the subjects had to put one half of the appliance twice a day in one of the assigned active solutions (0.1% benzoate, BA; 0.1% sorbate, SA or 0.2% chlorhexidine, CHX) and the other into NaCl. After 5 days, the developed biofilms were stained with two fluorescent dyes to visualise vital (green) and dead bacteria (red). Biofilms were scanned by confocal laser scanning microscopy and biofilm thickness (BT) and bacterial vitality (BV%) were calculated. After a washout period of 7 days, a new test cycle was started. The use of SA, BA and CHX resulted in a significantly reduced BT and BV compared to NaCl (p < 0.001). Differences between SA and BA were not significant (p > 0.05) for both parameters, while CHX showed significantly lower values. Both preservatives showed antibacterial and plaque-inhibiting properties, but not to the extent of CHX. The biofilm model enabled the examination of undisturbed oral biofilm formation influenced by antibacterial components under clinical conditions.  相似文献   
39.
This paper reports the treatment of oral lymphangiomas with carbon dioxide CO? Laser. Lymphangiomas are rare congenital lymphatic malformations. These lesions are most frequently diagnosed during childhood, are most commonly located in the head and neck region, and are extremely rare in the oral cavity. Oral lymphangiomas are of complex treatment due to the difficulty in performing a complete excision. CO? laser is the most often used laser in the oral cavity due to its affinity with water and high absorption by the oral mucosa. Several benefits of the use of CO? laser have been reported for surgical oral procedures. The cases reported herein were biopsy-proven lymphangiomas of the oral cavity. The surgical procedures were carried out under local anesthesia and a focused CO? laser beam (λ10.600 nm, Φ ~2 mm, CW/RSP) was used. At the end of the surgery, the laser beam was used on a defocused mode to promote better hemostasis. Neither sutures nor dressings were used after surgery. No medication and only mouthwashes were prescribed to all patients on the postoperative period. There were no postsurgical complaints from the patients and no relapses of the conditions were observed after follow-up periods of 12 and 18 months. The use of CO? laser was practical, easy to carry out and effective on the treatment of oral lymphangiomas, with no lesion recurrence.  相似文献   
40.

Objectives

This study investigated the effect of incorporating chlorhexidine in a self-etching primer on the bond strength of an adhesive resin cement to dentine and on antibacterial activity.

Methods

Experimental self-etching primers were prepared by adding chlorhexidine (CHX) diacetate to ED primer 2.0 (Kuraray Medical Inc.) to obtain chlorhexidine concentrations of 1.0 wt% and 2.0 wt%. Human occlusal dentine surfaces were conditioned for 30 s using the experimental primers or pure ED primer. Composite blocks were luted using Panavia F 2.0 (Kuraray Medical Inc.). After storage in water for 24 h, the bonded teeth were sectioned into 0.9 mm × 0.9 mm beams and stressed to failure in tension to examine microtensile bond strength (μTBS). Fractured surfaces were examined with a field-emission scanning electron microscopy (FE-SEM). The morphology of dentine surfaces that were conditioned with each primer was also observed under FE-SEM. An agar diffusion test was performed to examine the antibacterial effect of each primer against Streptococcus mutans and Enterococcus faecalis.

Results

Addition of chlorhexidine to the primer had significant effects (p < 0.001) on μTBS and antibacterial effect. No significant difference in μTBS was found between the groups that contained 0% and 1% chlorhexidine in the primer (p = 0.095). Conversely, the group that contained 2% chlorhexidine showed significantly lower μTBS and pronounced cohesive failures within the thin layer of the primer.

Conclusions

Incorporation of chlorhexidine into ED primer 2.0 showed significant antibacterial activities. Conditioning with the 1% chlorhexidine-containing primer had no adverse effect on μTBS.  相似文献   
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