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931.
The need for periodontal treatment in a group of dental school patients was estimated by means of the periodontal treatment need system (PTNS). The findings were related to information about the regularity of dental visits, awareness of own disease, and periodontal treatment experience. All the patients required motivation and oral hygiene instruction (treatment need, class A). All their quadrants needed scaling or adjustment of subgingival restorations (treatment need, class B). As many as 71% of the patients and about 49% of the quadrants needed periodontal surgery (treatment need, class C). The mean periodontal treatment time per patient was 279 min (4 h 39 min). The middle age group (30-59 years) required more treatment time than the oldest group (greater than or equal to 60 years). This was probably due to more missing teeth in the oldest age group. There were no significant differences in treatment need between males and females. The regular dental visitors had a greater periodontal treatment need than the individuals visiting their dentist less frequently. This finding emphasizes the responsibility of the general practitioner in diagnosing and treating periodontal disease.  相似文献   
932.
Cytotoxicity of amalgams, alloys, and their elements and phases   总被引:2,自引:1,他引:2  
The purpose of this study was to compare the relative cytotoxicity of amalgams, alloys, and their constituent elements and phases, by means of a rapid and sensitive in vitro cell culture test. Pure copper and zinc showed intensive cytotoxicity, significantly greater than that of pure silver and mercury. Pure tin was non-cytotoxic. The gamma-one phase (Ag2Hg3) revealed moderate cytotoxicity, which was significantly decreased by the addition of 1.5% and 5% Sn. However, the addition of 1.5% Zn to gamma 1 containing 1.5% Sn dramatically increased the cytotoxicity of gamma 1 to the same level as that of pure zinc. Whenever zinc was present in amalgams, higher cytotoxicity was revealed. High-copper amalgams showed the same cytotoxicity as a zinc-free low-copper amalgam. The addition of selenium did not reduce the cytotoxicity of amalgam. The cytotoxicity of amalgams was reduced after 24 h. The results of this study suggest that the major contributor to the cytotoxicity of alloy for amalgam is probably copper, while that for amalgam is zinc.  相似文献   
933.
Craniomandibular disorders are conditions encompassing various types of dysfunction of the stomatognathic system. To define the very nature of morbidity, both differential and pathological diagnosis are absolutely necessary. At present, each medical institution in this country has its own protocol for evaluating and treating craniomandibular disorders. This makes it difficult to exchange and compare data between institutions. In this paper, a protocol worked out by our department after a series of clinical tests and study is presented, and its merits and unresolved problems are discussed.  相似文献   
934.
The osteogenic potential of two composite graft systems using osteogenin   总被引:2,自引:0,他引:2  
The purpose of this study was to determine the quantity of new bone formation in critical sized calvaria defects in rats treated with two composite graft systems. The systems consisted of either a combination of the bone inductive protein (osteogenin) plus type I collagen (Os + C) or the combination of osteogenin with coralline hydroxyapatite (Os + HA). Additional treatments consisted of coralline hydroxyapatite (HA) or untreated control defects. After 28 days the calvaria were recovered and processed for quantitative radiography (radiomorphometry) and histomorphometry. Histomorphometric results were based on quantitation of regenerated trabecular bone. Results indicated that the Os + C combination produced substantially more bone than the Os + HA, HA, or control groups (P less than 0.05). Radiomorphometric assessment was based on the detection of radiopacity in the calvarial wounds. Due to the radiopaque property of HA, it was not possible to accurately quantitate the radiopacity of the regenerating bone from HA and host bone. Therefore, conclusions about the efficacy of the treatments must be derived from histomorphometric data. Results from histometric measurements of healing indicate that the Os + C combination has the greatest potential for regenerating calvarial bone defects. The potential for osteogenin in regenerating alveolar bone lost due to periodontal disease is suggested by these studies.  相似文献   
935.
936.
937.
Campylobacter rectus (formerly Wolinella recta ) in periodontitis lesions was studied relative to age and sex distribution, relationship to disease-active periodontitis, response to periodontal debridement and in vitro antimicrobial susceptibility. Subgingival C. rectus was collected with paper points, transported in VMGA III and plated onto nonselective enriched brucella blood agar and Hammond's selective medium for C. rectus , both incubated anaerobically. C. rectus was recovered from 80% of 1654 periodontitis patients. Although the organism showed similar age and sex occurrence, its proportional recovery in culture-positive adults was inversely related to increasing age ( r = 0.999, P <0.001). The organism was positively associated (summary odds ratio = 2.95) with disease activity in a 24-month longitudinal study of 93 adult periodontitis patients on maintenance therapy. C. rectus decreased from 8.2% to 0.7% following local periodontal debridement of 20 culture-positive adult periodontitis patients. The organism exhibited high in vitro susceptibility to therapeutic levels of tetracycline hydrochloride, metronidazole, penicillin G and ciprofloxacin. These findings further delineate the epidemiology and potential pathogenic role of C. rectus in human periodontitis.  相似文献   
938.
939.
An epidemiologic survey of facial fractures and concomitant injuries   总被引:9,自引:0,他引:9  
A 5-year review of facial fractures and concomitant injuries at a level 1 trauma center is presented. The anatomic location of the facial fractures, age and sex of the patients, cause of injury, and associated systems injuries are presented. The majority of facial fractures were found in males; the most prevalent age range was 16 to 30 years. Mandible fractures outranked zygomatic and maxillary fractures (6:2:1). Assaults and motor vehicle accidents were the most frequent causes of facial fractures, and lacerations followed by neurologic and orthopedic injury were the most frequently encountered concomitant injuries. Motor vehicle accidents were the most frequent cause of associated injury.  相似文献   
940.
In this study, a mouthrinse containing calcium lactate was tested for its effect on the accumulation of dental plaque and on the concentrations of calcium and phosphorus therein. Human volunteers rinsed four times per day with a calcium lactate (165 mmol/l) solution for 1 week. Plaque samples, collected 16 h after the last rinse, were analyzed chemically. Calcium lactate rinses had no effect on the plaque score, but resulted in approximately twofold increases of calcium and phosphorus in plaque. The incorporation of monofluorophosphate (5 mmol/l) into the rinsing solution failed to show any significant influence on calcium, phosphorus, and fluoride levels in plaque. Increased mineral deposition in the plaque may provide an explanation for the reduced caries development earlier observed in rats fed a diet containing calcium lactate.  相似文献   
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