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81.
Background: To our knowledge, prospective studies (matched for sex, smoking, and diabetes) that investigated the influence of compliance in the progression of periodontitis and tooth loss in periodontal maintenance therapy (PMT) programs were not previously reported. Methods: A total of 58 regular complier (RC) and 58 erratic complier (EC) individuals were recruited from a prospective cohort with 238 patients under PMT and matched by sex, diabetes, and smoking habits. A full‐mouth periodontal examination that included bleeding on probing (BOP), probing depths (PDs), clinical attachment levels, and number of teeth were determined at all PMT visits during a 3‐year interval. The influence of variables of interest was tested through multivariate logistic regression. Results: The progression of periodontitis and tooth loss was significantly lower among RC compared to EC patients. A higher progression of periodontitis was observed among EC patients who smoked. The final logistic model for the progression of periodontitis in the RC group included smoking (odds ratio [OR]: 4.2) and >30% of sites with BOP (OR: 2.8), and the final logistic model for the progression of periodontitis in the EC group included smoking (OR: 7.3), >30% of sites with BOP (OR: 3.2), PDs of 4 to 6 mm in 10% of sites (OR: 3.5), diabetes (OR: 1.9), and number of lost teeth (OR: 3.1). Conclusions: RC patients presented a lower progression of periodontitis and tooth loss compared to EC patients. This result highlighted the influence of the pattern of compliance in maintaining a good periodontal status. Moreover, important risk variables such as smoking and diabetes influenced the periodontal status and should be considered when determining the risk profile and interval time for PMT visits.  相似文献   
82.
The purpose of the present investigation was to compare the presence of Epstein-Barr virus type 1 (EBV-1) and of Human Cytomegalovirus (HCMV) in crevicular fluid samples from deep and shallow periodontal pocket sites of Brazilian patients with aggressive periodontitis. A total of 30 systemically healthy patients with aggressive periodontitis participated in the study. Paper points were inserted into 2 gingivitis sites (<3 mm) and into 2 periodontitis sites (>5 mm) in each patient. PCR assay was used to identify genomic copies of HCMV and EBV-1. Twenty-three patients (77%) were positive for EBV-1, while only 2 patients (6%) were positive for HCMV. The McNemar test revealed a positive association between EBV-1 and periodontal lesions (p=0.043). Thirty-four (57%) out of 60 periodontitis sites were positive for EBV-1, whereas 18 (30%) gingivitis sites were positive (p=0.01). Only two sites (6.7%) were positive for HCMV. No positive association was found between HCMV and periodontitis or gingivitis (p=0.479). The elevated occurrence of EBV-1 DNA in periodontal pockets of patients with aggressive periodontitis supports a possible periodontopathic role of this virus.  相似文献   
83.

Objectives:

The antiplaque and antigingivitis effect of Lippia Sidoides (LS) was evaluated in this in vivo investigation.

Material and Methods:

Twenty-three subjects participated in a cross-over, double-blind clinical study, using 21-day partial-mouth experimental model of gingivitis. A toothshield was constructed for each volunteer, avoiding the brushing of the 4 experimental posterior teeth in the lower left quadrant. The subjects were randomly assigned initially to use either the placebo gel (control group) or the test gel, containing 10% LS (test group).

Results:

The clinical results showed statistically significant differences for plaque index (PLI) (p<0.01) between days 0 and 21 in both groups, however only the control group showed statistically significant difference (p<0.01) for the bleeding (IB) and gingival (GI) index within the experimental period of 21 days. On day 21, the test group presented significantly better results than the control group with regard to the GI (p<0.05).

Conclusions:

The test gel containing 10% LS was effective in the control of gingivitis.  相似文献   
84.
AIM: The aim of this article is to present a case of Paracoccidioidomycosis with involvement of the oral cavity but without pulmonary manifestations. BACKGROUND: Paracoccidioidomycosis is a fungal infection caused by Paracoccidioides brasiliensis. It is an endemic disease representing a serious health problem for Latin American countries, especially Brazil. This infection primarily affects the lungs of adult men and is acquired through inhalation or accidental inoculation of the fungus. It can spread to other organs and tissues, mainly the oral cavity. Administration of antifungal medication always resolves the disease. REPORT: A 58-year-old black male presented with three painless, ulcerated, mulberry-like granulomatous lesions located in the floor of the mouth, on the superior alveolar ridge, and on the hard palate, which had evolved over a period of two years. Facial asymmetry was observed due to edema in the lower lip and lymphadenopathy. He had smoked for more than six years but showed no evidence of lung alterations, productive cough, or fever. Panoramic radiography showed no signs of a bone lesion in the jaws. Both a radiograph and a CT scan of the thorax showed no areas of nodular infiltration. Fibrobronchoscopic examination of the entire respiratory tract was normal. Biopsies of the oral lesions were performed, and tissue sections exhibited oral mucosa coated with non-keratinized stratified squamous epithelium with acanthosis and focal areas of exocytosis. The underlying connective tissue showed an intense lymphocytic and polymorphonuclear infiltrate in addition to multinuclear giant cells and coagulation necrosis. A special stain used for fungus (the Grocott-Gomori method) was positive. Pulmonary biopsy exhibited aerial spaces containing macrophages, dark granular hemossiderin, and absence of fungus. This was considered normal. In agreement with the recommendation of pneumologists 400 mg/day of ketoconazole was prescribed for the patient. After two months of treatment, even though the oral lesions had resolved completely, the therapy was maintained for six months more. One year after following treatment the patient was in good health and free of any signs of a recurrent infection. SUMMARY: Based on clinical, radiographic, and histologic findings the differential diagnosis included paracoccidioidomycosis and squamous cell carcinoma. Following clinical and biopsy examinations of the oral lesions and the lungs a final diagnosis of paracoccidioidomycosis was made. This is a prime example of oral manifestations of a systemic disease in which the dentist is the initial health care professional to evaluate the patient due to the location of the lesions.  相似文献   
85.
Coloring in drinks decreases the color stability of composite restorations, reducing their longevity. The purpose of this in vitro study was to evaluate the effect of immersion media on color stability of seven different composite resins (Solidex - Shofu, Resilab-Wilcos, Signum - Heraeus, Epricord - Tokuyama, Adoro - Ivoclar Vivadent, Admira - Voco and Sinfony - 3MESPE). Seven resin-based composite specimens were prepared using a cylindrical teflon mold 2 mm thick and 10 mm in diameter Fifteen specimens of each resin were light-cured according to manufacturers' instructions and randomized into 3 groups (n= 5) according to immersion media: coffee, cola beverage and water A digital spectrophotometer Easy Shade (VITA) was used to evaluate the color changes at baseline and 7 days after immersion in each solution. Specimens were stored in the different staining media for 24 h/day during one week. The color differences were analyzed by two-way ANOVA and Tukey 's test (p< 0.05). Color change was observed after one week of immersion and there were statistical differences in staining, composite and interaction factors. The least staining was observed in Admira (deltaE= 3.934+/-0.814) and Resilab (deltaE= 3.993+/-0.735), followed by Adoro (deltaE= 4.044+/-1.001), Epri-cord (deltaE= 4.049+/-1.234), Signum (deltaE= 4.260+/-1.785), Solidex (deltaE=5,122+/-0.534) and Sinfony (deltaE=5.126+/-0.838). All of the composites tested except Adoro were susceptible to staining by substances present in coffee and cola, when stored in beverage for seven days. The lowest deltaE means were obtained with Admira.  相似文献   
86.
Ameloblastic fibroma is a relatively rare benign odontogenic tumor in which both the epithelial and ectomesenchymal components are neoplastic. An 8-year-old Caucasian boy was referred to the dentist for evaluation of failed eruption of the maxillary left first molar. The panoramic radiograph showed a well-circumscribed unilocular radiolucency involving an unerupted maxillary left first permanent molar. The lesion was enucleated and the material was sent for histopathologic examination. Microscopically, it was composed by cords and islands of odontogenic epithelium in a myxoid cell-rich stroma that closely resemble the dental papilla with histopathological diagnosis of ameloblastic fibroma. After 24 months of follow-up no recurrence was observed and the maxillary left first molar erupted spontaneously through the buccal mucosa and was aligned with a fixed orthodontic appliance. This case emphasized the importance of careful differential diagnosis of intraosseous oral lesions and reported a rarity of the lesion and its atypical location.  相似文献   
87.
BackgroundThe objective of this study was to compare dentists’ perceptions of gloss values of composite specimens with increased levels and to identify the gloss value considered to be clinically acceptable.MethodsDisk-shaped composite specimens were finished and polished 3 ways: metallurgically using silicon carbide papers and alumina paste, manually using Enhance finisher and PoGo polisher (EP) (Dentsply Sirona), and manually using Sof-Lex (SLex) disks (3M). Specimens were produced with surface gloss ranging from 0 through 100 gloss units (GU) in increments of approximately 10 GU as measured with a glossmeter. A GU of 0 was nonglossy, and a GU of 100 was perfectly glossy. Ten dentists evaluated the specimens, ranking them in order from low to high gloss and in 4 groups: low (dull or rough), medium (moderate gloss, clinically unacceptable), high (glossy, clinically acceptable), and superior gloss. The authors performed Spearman correlation analysis (α = 0.05).ResultsFor each finish and polish method, there was an excellent correlation between the machine-measured (actual) gloss ranks and the clinician-evaluated gloss ranks (r2 ≥ 0.95). There was no difference in perception of surface gloss of the composite when metallurgically polished (with silicon carbide papers and alumina paste) or polished with EP to the same GU. There was a slight difference in gloss perception when comparing the 2 different commercial polishing systems.ConclusionsTen dentists consistently perceived gloss of 40 through 50 GU as clinically acceptable. However, the composite was considered clinically acceptable at a lower gloss (40 GU) when polished with SLex disks than when polished with EP or metallurgically (50 GU).Practical ImplicationsGloss values of 40 through 50 GU are considered to be clinically acceptable for resin composites.  相似文献   
88.
Impacted injuries of the head and neck are uncommon. Associated injuries can be present and can be a serious problem. We present an unusual clinical case and discuss the management of this complex injury. Head and neck injuries deserve special attention because of their enormous functional and esthetic significance. Contusion, abrasion, retained foreign bodies, laceration, and avulsion are some of the most frequent injuries. Impalement injuries are not so common. These lesions combine aspects of blunt and penetrating trauma and usually result from penetration by a large, rigid, blunt-tipped object that traverses a certain body area in a through-and-through fashion and often remains in situ at the time of presentation. There have been many case reports describing these injuries in the trunk and extremities; however, cases of head and neck impalement are still lacking in number. A case of an unusual cervical impalement is presented, together with a discussion of the management of this complex injury.  相似文献   
89.
OBJECTIVE: The purpose of this study was to demonstrate the sensitivity and specificity of multislice computerized tomography (CT) for diagnosis of maxillofacial fractures following specific protocols using an independent workstation. STUDY DESIGN: The study population consisted of 56 patients with maxillofacial fractures who were submitted to a multislice CT. The original data were transferred to an independent workstation using volumetric imaging software to generate axial images and simultaneous multiplanar (MPR) and 3-dimensional (3D-CT) volume rendering reconstructed images. The images were then processed and interpreted by 2 examiners using the following protocols independently of each other: axial, MPR/axial, 3D-CT images, and the association of axial/MPR/3D images. The clinical/surgical findings were considered the gold standard corroborating the diagnosis of the fractures and their anatomic localization. The statistical analysis was carried out using validity and chi-squared tests. RESULTS: The association of axial/MPR/3D images indicated a higher sensitivity (range 95.8%) and specificity (range 99%) than the other methods regarding the analysis of all regions. CONCLUSION: CT imaging demonstrated high specificity and sensitivity for maxillofacial fractures. The association of axial/MPR/3D-CT images added important information in relationship to other CT protocols.  相似文献   
90.
Collagen materials have been utilized in medicine and dentistry because of their proven biocompatibility and capability of promoting wound healing. The aim of the present experimental study was to perform a histomorphometric evaluation of the effect of bovine collagen granules on post-extraction alveolar wound healing in rats. Twenty male Wistar rats were submitted to bilateral extraction of the first lower molars under ketamine/xylazine anesthesia according to the technique previously described by Guglielmotti and Cabrini. Sterile Bovine collagen granules of approximately 80 +/- 10 microm (Membracel G, Lab. Celina, Buenos Aires) were hydrated with saline solution and placed into the right mesial socket (experimental side) with gentle pressure, completely filling the site. The contralateral sockets were considered as the control side. Sutures were not performed. After surgery neither special diet nor antibiotics were given. The rats were fed rat chow and water ad libitum. All the animals were killed on the 30th day following surgery by ether overdose. The jaws were dissected, radiographed, decalcified, and embedded in paraffin. Sections were obtained at the level of the first molar mesial socket in a buccolingual orientation and stained with hematoxylin-eosin. The trabecular area and volume density of trabecular bone were measured histomorphometrically. The trabecular area was greater in alveoli treated with collagen granules than in control alveoli (P<0.05). Values of volume density of trabecular bone were greater in experimental than in control sockets (P<0.05). This experimental study provides evidence for the use of bovine collagen granules as bone grafting material, as a therapeutic alternative to fill postextraction sockets.  相似文献   
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