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81.
Electrotherapy and hyperbaric oxygen therapy have been added to physical therapy to treat patients with postsurgery and radiation sequelae. Problems of reduced oral opening and range of head movement, soft tissue necrosis, osteoradionecrosis, and delayed wound healing were addressed in 37 patients over a 3-year period. Of this group, 16 irradiated maxillary resection patients were specifically followed up to determine the effectiveness of the new modalities on improving reduced oral opening. Although healing and the quality of the soft tissues showed marked improvement there was no significant improvement in oral opening.  相似文献   
82.
Toothbrushing force in relation to plaque removal   总被引:1,自引:0,他引:1  
Abstract This was a 2-part study. The purpose of the 1st part was to examine the relationship between brushing force and plaque removal efficacy comparing a regular manual toothbrush (M) with an electric toothbrush the Braun Oral-B Plak Control* (B). The study consisted of a single oral prophylaxis followed by 5 experiments which differed solely in respect to toothbrushing force. At baseline (after 24-h plaque accumulation), the amount of dental plaque was evaluated and subsequently, the subject's mouth was brushed by a dental hygienist. Brushing was carried out in a random split-mouth order. Either the 1st and 3rd quadrants or the 2nd and 4th quadrants were brushed with 1 toothbrush and the 2 remaining quadrants with the other. The available time for the brushing procedure was 2 min. After brushing, the amount of remaining dental plaque was assessed. The force used in experiment 1 through 5 was 100, 150, 200, 250, 300 g, respectively. The results show that when brushing force is increased, more plaque is removed with either of the two brushes. Except for the high brushing force (300 g), the electric toothbrush removed more plaque than the manual brush. The purpose of the 2nd part was to evaluate the habitual brushing force which individuals use with various toothbrushes. Besides a manual toothbrush (M), 3 electric toothbrushes were examined, the Rotadent® (R). Interplak® (I) and Braun® (B). 20 subjects were selected on the basis of being ‘good brushers” (plaque score at screening <25%). At baseline, each subject randomly received 1 of the 4 brushes. They were allowed a training period of 3 weeks at the end of which they were asked to abstain from brushing for at least 24 h. The plaque (Turesky modification of the Quigley & Hein) was scored, after which the subjects brushed their teeth (2 min) with the assigned toothbrush equipped with a strain gauge. A computer set–up measured (100 Hz) and calculated the mean brushing force. After brushing, the amount of remaining plaque was assessed. The design of the study was a 4-way cross-over. The results show that with a manual brush, considerably more force is used than with the electric brushes (R=96. 1 = 119. B= 146, M=273). No significant relation between brushing force and plaque removal was demonstrated for any of the brushes.  相似文献   
83.
The adsorption of nitrate ions on gold and platinum electrodes in acid solution has been studied in acidic solution using in situ FURS. It is found that nitrate is adsorbed probably with a two-fold coordination on gold electrodes as suggested by the adsórbate potential-dependent spectral feature centered between 1440 and 1460 cm?1. In addition, partial reduction of the nitrate ions at more negative potentials (ca. 0.05 V) generates nitrite ions in solution. These ions are co-adsorbed with nitrate ions in the double layer region of potentials. The nitrite ions seem to be adsorbed O-down with a one-fold or two-fold coordination. Platinum electrodes are found to be much more active catalytically to nitrate reduction than gold electrodes. The reduction of nitrate ions at potentials below 0.8 V generates an adsorbed product presenting a potential-dependent band at 1540 to 1580 cm?1 which has been identified as adsorbed NO.  相似文献   
84.
Although a wide range of bacterial species has been isolated from infected dental root canals it remains necessary to determine whether any particular group of such bacteria is associated with specific endodontic symptoms and clinical signs. In this study 30 root canals were examined microbiologically; of these, 14 were associated with pain, 20 with tenderness to percussion, 23 presented with wet root canals, seven with swelling, five with purulent exudate and four with a sinus. Clinical and microbiological correlation was observed particularly with regard to pain where anaerobes were isolated from 93% of painful canals and only from 53% of painfree canals. The former yielded means of 2.5 anaerobic species and 1.6 facultative species per canal, compared with 1.5 and 2.4 in painfree canals. Prevotella spp. were isolated from 64.2% of painful canals and 12.5% of painless canals (P<0.01) similarly, peptostreptococci were isolated from 71.4% of painful and 31.3% of painless canals (P<0.05). It was concluded that a significant association exists between pain and the presence of Prevotella and Peptostreptococcus spp. in dental root canals.  相似文献   
85.
Acidic proline-rich phosphoproteins and phosphopeptides are abundant components of parotid and submandibular salivary secretions in man and in the subhuman primate, Macaca fascicularis. The major acidic proline-rich proteins and the proline-rich phosphopeptide, statherin, of man and macaques have been shown to be potent inhibitors of calcium phosphate precipitation and are thought to function in the oral environment by maintaining saliva supersaturated with respect to calcium phosphate salts. Little is known about the biosynthesis of these proline-rich phosphoproteins and peptides, and the aim of the present work was to determine the structural relationship between statherin precursors and native human and macaque statherin. RNA was isolated from human submandibular gland, and poly(A+) mRNA was selected by affinity chromatography on oligo(dT) cellulose and translated in a reticulocyte lysate. Electrophoretic analysis of the translation products revealed that this mRNA directed the synthesis of a large number of polypeptides with Mrs ranging from 5000 to 70,000. Immunoprecipitates, prepared with an antiserum directed against human statherin, contained a single component with a Mr of 7800, approximately 2000 daltons larger than native statherin. Radiosequencing of the in vitro precursor of statherin in immunoprecipitates demonstrated the presence of a 19-residue signal peptide. These results suggest that statherin is derived from a unique structural gene, and does not result from proteolytic processing of a large polyprotein precursor.  相似文献   
86.
87.
A method for the preservation of the olfactory nerve filaments in cases of hypertelorism correction is described. The cribriform plate is completely resected and the nerve filaments gathered in the midline after medial rotation of the orbits. In contrast to Converse's (1970) procedure of paramedian osteotomies the method allows full correction of all degrees of hypertelorism, even in the most extreme cases, without olfactory nerve impairment.  相似文献   
88.
Xerostomia: evaluation of a symptom with increasing significance   总被引:12,自引:0,他引:12  
Xerostomia is the subjective sensation of oral dryness. Although it is most commonly associated with salivary gland dysfunction, it may also occur with normal gland activity. Xerostomia may be an early symptom of several morbid systemic conditions with important implications for the medical and dental management of patients. Oral dryness also has negative effects on an individual's emotional well-being and quality of life. The complaint of xerostomia necessitates a complete evaluation of a patient's general health, salivary gland function, and oral motor and sensory abilities. The salivary gland assessment includes symptom review, analysis of glandular secretions, scintiscanning, and minor labial gland biopsy. No single component is sufficient to adequately diagnose the presence, extent, or cause of salivary dysfunction. Treatment of a dry mouth, to date, is mainly palliative in nature, with the intent of preserving oral structures and functions. Better therapies are essential in the management of xerostomia, whatever the cause. The importance of xerostomia as a symptom is increasingly recognized in medicine and dentistry. The dentist is commonly the first health professional to hear this complaint and may be critical in directing a full and appropriate evaluation.  相似文献   
89.
An interesting case of a trauma-induced tender mass of the buccal mucosa in a 45-year-old man was presented. Following surgery, the patient was relieved from pain. Microscopically, the mature adipose tissue is unique in that it contained a single enlarged Pacinian corpuscle near the deep margin. This is the hitherto undescribed intraoral lesion of Pacinian neuroma in the herniated buccal fat pad.  相似文献   
90.
Maxillary distraction osteogenesis is indicated in severe angle class III malocclusions, and severe maxillary hypoplasia among some cleft patients and other craniofacial deformities. Twenty patients, aged 8-48 years (mean 17.8+/-10.5 SD) with maxillary and midfacial hypoplasia were treated. The follow-up period was 13-65 months (mean 35+/-16.3 SD). A trans-sinusal maxillary distractor was placed intraorally at each side of the maxilla. The distraction vector was predicted using specialist software, and was transferred to the patients using stereolithographic models and individual templates. A (high) Le Fort I type osteotomy was performed. The amount of activation varied from 8 to 17.5 mm (mean 13.1+/-2.9 SD). Soft and hard tissue formation resulted in complete healing across the distraction gaps. The distractors are almost completely submerged, and can be left in place as long as necessary to avoid relapse. Wit's appraisal was used to measure the stability of the long-term distraction results. Results up to 5 years after distraction showed considerable maxillary advancement with long-term stability. Ongoing growth of the facial skeleton must be considered when distraction osteogenesis is chosen in growing patients.  相似文献   
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