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At least 1,513 records · Page 84Linked to original sources
PubMed1989

[Electromyographic study on masticatory function of the telescope denture wearers in the Kennedy Class II mandible].

Masticatory function of 10 telescope denture wearers in the Kennedy class II mandible patients was evaluated with electromyography. Electromyographic activity during mastication with kamaboko and peeled raw carrot was recorded from bilateral masseter and the anterior part of temporal muscles at each interval: Before treatment, immediately after denture insertion and 2, 4, 6, 8 weeks after respectively. Mean of duration, interval and cycle of EMG activities, coefficient of variation and average variation were calculated. The results were as follows: 1. Means of duration and cycle times decreased immediately to 2 weeks after denture insertion. 2. EMG activities during raw carrot chewing became regular immediately to 2 weeks after denture insertion, and within 4 weeks in kamaboko chewing. These results suggest that telescope dentures would be adapted to stomatognathic system within short period after denture insertion.

Denture, Overlay↗
PubMed1989

[Analysis of the denture dynamics in R.P.D.'s. 1. Methods for analyzing the denture dynamics of free-end-saddle].

Excess denture movement during function may cause to jeopardize the resorption of the residual ridges and the mechanical trauma on the abutments in the partially dentate mouth. A removable partial denture (R.P.D.'s) should be so constructed that the artificial teeth on the denture base will be stabilized in their spatial position by way of the compensatory support due to the remaining abutments and the residual ridges. In this pilot study, the ordinary denture movement, that is the denture dynamics in function of the free end saddle R.P.D.'s was measured in the test denture assembly. The denture dynamics was assessed in two ways: The displacement sensors revealed the vertical and the horizontal movement of the denture base during function. They were based on the field magnetic effect and with good lineality. Tiny accerelometer was attached to the denture base to detect the accerelation during function. Ordinary mastication was not interefered by both methods. The Author has already reported the palpation test for diagnosing the denture dynamics of the free end saddles in clinics. This method was discussed objectively against the accerelometry on fifty patients. Two methods have revealed the good coincidence with each other to detect the dynamics of the free end saddles.

Alveolar Bone Loss↗
PubMed1989

[Prosthodontic treatment for a partial mandibulectomy patient. A mandibular non-reconstructed case].

One of the most consistently frustrating areas of maxillofacial rehabilitation is the treatment of patients who have had radical cancer surgery of the tongue, floor of the mouth, and mandible. The patient described in this report, was a 66-year-old man who had squamous cell carcinoma of the right jaw. The right body of the mandible distal to the right cuspid was resected, and this part of the mandible was not reconstructed. For this mandibulectomy patient, we have treated with the removable partial denture using 30 degree teeth and TS telescope crown as retainer, registrating maxillomandibular relation with Gothic arch tracer and MKG. In addition, masticatory function in this patient was evaluated on tooth contact, tapping pattern, masticatory efficiency and rhythm of mastication. Consequently, 4 to 8 weeks later, tapping pattern and centric occlusion was stabilized, and masticatory function was improved. We will continue to observe this case in long term.

Aged↗
PubMed2006

[Strategy of prosthodontics in an aged society with fewer children].

In this article, intrinsic problems lying in Prosthodontics research and educational field were pointed out and Prosthodontics as it ought to be as a nature science was discussed. Prospect of prosthetic dentistry/Prosthodontics as a clinical science was categorized the following four and discussed: 1) systematizing of conventional Prosthodontics, such as crown, bridge, partial and complete denture, 2) contribution to oral rehabilitation of mastication, swallowing, and speech for elderly and inpatient elderly, 3) innovation of prosthetic dentistry using more comfortable and aesthetic prosthesis, such as Implant and Adhesive Dentistry, and 4) translational research. Finally, essential prerequisites to achieve bright future of Prosthodontics were proposed.

Aged↗
PubMed2006

[Future research needs and strategies for orofacial pain and oral motor disorders].

Musculoskeletal disorders in orofacial region are known to induce mastication disability and decrease the patients' quality of life levels. Additionally, the prevalence of those disorders tends to increase in elderly. However, since the existing therapies are not fully effective and medical expenses for those disorders are expanding, a prompt solution is necessary especially in aging societies like Japan. In addition, investigations for those disorders are important, because the research findings would be useful for the investigation of similar disease in other organs. Therefore, it is possible to consider that they can directly associate with general health and the universality of prosthodontics. In order to solve the above problems, two different research strategies are desirable. First, to improve the current curative effect, the effectiveness of existing diagnostic system and treatment modalities should be evaluated using high quality clinical studies. Second, as the research strategies on a long-term basis, investigations, which target the pathology and the contributing factors in a biological point of view are essential. This article will discuss about the research strategy to elucidate the pathology and the factors, which play important roles in the disease mechanisms, based on the previous and ongoing physiological research findings. Furthermore, I would like to review the useful newly developed technologies for the research strategy and new research fields, to enhance the value of prosthodontics and discuss about our future research direction.

Facial Pain↗
PubMed2006

[Objective evaluation of masticatory function in temporomandibular disorders patients].

PURPOSE: The purpose of this experiment was to objectively evaluate the masticatory function in TMD (Temporomandivular disorders) patients. METHODS: The quantitative indicators of muscular activity, stability of movement, and masticatory efficiency during mastication were compared among the following three groups; 10 healthy subjects, 10 patients with arthrogenous TMD, and 10 patients with myogenous TMD. For muscular activity, the integral value of the masseter muscular activity was calculated. For stability of movement, a comprehensive indicator was established after principal component analysis using the data of the seven indicators of stability of path and rhythm. For masticatory efficiency, the amount of glucose extraction after gummy-jelly chewing was measured by a blood glucose testing device. RESULTS: The cumulative value of masseter muscular activity and the amount of glucose extraction after gummy-jelly chewing were larger in the healthy subject group than in the groups with arthrogenous or myogenous TMD, and these differences between the healthy subject group and the other two groups were statistically significant. On the other hand, the value of the comprehensive indicator was significantly smaller in the healthy subject group than in the groups with arthrogenous or myogenous TMD. CONCLUSION: It was suggested that the masticatory function in TMD patients is much inferior to that in healthy subjects.

Adult↗
PubMed2006

[Case report of prosthetic treatment for defected jaw with enucleation of the right maxillary sinus tumor].

PATIENT: The patient is a 71-year-old woman who had undergone a gingivectomy due to a gingival carcinoma of right maxillary sinus and a denture was made for the defected jaw. DISCUSSION: During three years and six months, |3 serves as the guidance tooth had suffered from various symptoms, from the detachment of the neighboring tooth to the use of an OP anchor followed by a partial fracture of the cuspid root. However, |3 has not been removed in accordance to the patient's request. In addition, a relining provided indirectly to the denture, it is still maintained and used for mastication, pronunciation and swallowing functions without difficulty. CONCLUSION: This is a case that a denture was made for the defected jaw. However, it is important ot take measures in the future, as the remaining tooth is not expected to be preserved for long.

Deglutition↗
PubMed2000

Histological study of masseter muscle in a mouse muscular dystrophy model (mdx mouse).

Histological changes in the masseter muscle were observed over time in mdx mice, a muscular dystrophy model. It was found that marked necrosis occurs about the time of weaning at around 4 weeks of age; then the tissue actively regenerates at 8 weeks and stabilizes as regenerated muscle with centronuclei at 15 weeks old. This study examined the centronucleus in regenerated muscle. The process from necrosis to regeneration in muscle fibers occurs a little later in the masseter muscle than in other limbic muscles. Regenerated muscles observed around 15 weeks after birth showed a moth-eaten appearance. Transmission Electron Microscope (TEM) observation of transverse sections of muscle fibers revealed that myofibrils surrounded lost regions in the area showing a moth-eaten appearance. Thus, some defensive mechanism may affect the ability of muscle fibers to maintain a function close to normal in mdx mice even though the muscle fibers develop muscular dystrophy. The function of the masseter muscle drastically changes from sucking to mastication behavior at around 4 weeks, and this was considered to influence the morphological changes in the muscle tissue. The moth-eaten appearance seen at 15 weeks may represent an appropriate myofibril reconstruction preventing invasion of the lost regions.

Aging↗
PubMed1989

[The effect of food consistency on conditioned avoidance response in mice and rats].

The purpose of this study was to examine the effects of chewing a hard and soft diet on acquisition of conditioned avoidance response in mice and rats. 76 C57BL mice and 38 Wistar rats were divided into 2 groups respectively 20 days after birth. One group was fed a solid diet and another was fed a powder diet containing the same components as the solid one (Nihon Crea Company, CE-2). Using the avoidance conditioning system of Gunma University, conditioned avoidance experiments started at the age of 8 weeks and the rate of avoidance (number of avoidance/number of trials) was measured. The mean percentage of avoidance rates in the solid diet group were significantly higher than those of powder diet group at level of 1% in mice and 5% in rats. These results suggest that mastication of a hard diet in younger animal may facilitate their brain function more than that of a soft diet.

Animals↗
PubMed1990

The fine structure of the fibrous zone of articular cartilage in the rat mandibular condyle.

The ultrastructure of the articular fibrous zone of the rat mandibular condyle was observed at 3 and 6 weeks of age in order to investigate the histological changes that occur during the establishment of mastication after suckling. We divided the articular fibrous zone into two layers (F1 layer and F2 layer). The F1 layer was composed of fibroblast-like cells, macrophage-like cells, and the matrix which consisted of granular or fibrillar material, loosely arranged small bundles of collagen fibrils with uniform thickness of 30-50 nm, and independent microfibrils. The F1 layer was continuous with the synovial membrane without any distinct boundary in its peripheral area. Mitotic figures could infrequently be observed in the fibroblast-like cells. The cells in the F2 layer closely resembled fibroblasts. The matrix in the F2 layer mostly consisted of densely arranged bundles of collagen fibrils which are not of uniform diameter ranging 40-100 nm. Elastic fibers occurred among the collagen fibrils. The F1 layer which was observed clearly at 3 weeks almost disappeared at 6 weeks of age. It is confirmed that the F1 layer resembling the synovial membrane exists over the condyle up to the weaning period about 3 weeks of age but it degenerates before 6 weeks of age when the masticatory function is established.

Animals↗
PubMed2002

Satisfaction of orthognathic surgical patients in a Malaysian population.

Thirty-one patients treated at the Faculty of Dentistry, University of Malaya, were assessed for their satisfaction following orthognathic surgery. The female to male ratio was 22:9 with an age range of 17 to 36. Almost all patients (97%) listed appearance as one of their rationales for surgery. More males (78%) than females (59%) wanted functional improvement, while more females (91%) than males (33%) hoped for improvement in self-confidence. All patients reported esthetic improvement while 68% each reported improvement in mastication and self-confidence. Slightly more than half (52%) chose esthetic improvement as the single most important factor resulting in satisfaction. Almost ninety percent of male patients claimed satisfaction with functional improvement, while 68% of those who found satisfaction in improved self-confidence were females. Eighty-seven percent rated their post-surgical changes as being well accepted by their family. The impact of these findings on the success of the surgery and the need to reinforce verbal communication with printed pamphlets are emphasized.

Adolescent↗
PubMed1988

Site and extent of neutral detergent fiber digestion, efficiency of ruminal digesta flux and fecal output as related to variations in voluntary intake and chewing behavior in heifers.

Six heifers (1/4 Brahman x 1/4 Jersey x 1/2 Angus, 290 kg avg wt) with ruminal, duodenal and ileal cannulas were given ad libitum access to a corn silage-based diet with or without 100 mg monensin.hd-1.d-1 in a two-period crossover design. There was no significant effect of monensin on voluntary intake (VI), flow of NDF to the abomasum, fecal output or the efficiency of transfer of NDF to the duodenum (unitary fluxes of NDF through the reticulo-omasal orifice, number.g NDF.(kg BW.75)-1). Monensin increased extent of NDF digestion (NDFD) in the dorsal (P = .07) and ventral (P = .09) ruminal sac. As a fraction of the total tract NDFD, NDFD increased progressively in dorsal rumen (.214), ventral rumen (.548) and duodenal (.818) sites. The VI among individual heifers was negatively related to unitary fluxes of NDF through the reticulo-omasal orifice (P = .001) and to the extent of digestion of potentially digestible NDF (PDNDFD) in the ventral rumen (P = .006) and duodenum (P = .032), but not in the dorsal rumen (P = .720) or in the total tract (P = .785). Fecal output of NDF was negatively related to unitary times of eating (P = .027), ruminating (P = .001), masticating (P = .001) and unitary number of rumination boli (P = .001). These relationships all were influenced (P = .001) by individual heifer.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

Ultrastructure of vascular capillary of lingual filiform papillae in the mole (Mogella wogura wogura).

Detailed observation of the structure of filiform papillae (FP) and microvasculature of those papillae in Japanese Azuma mole were described. In the anterior and medial regions, FP was cylinder in shape with two processes. In the posterior region, it had a long, sharp conical shape. The microvascular casts showed two types of hairpin-shaped capillary loops on three regions of the tongue. In the anterior and medial regions, the end of the capillary loops were shaped like a spoon. In contrast, in the posterior region, it was knot-like end of capillary loop. Since the shape of capillary loop was more complex in the anterior and medial regions than that in the posterior region, it was speculated that the spoon-like end of capillary loops of the FP in the anterior and medial regions supply nutrients to the filiform papillary cells and may be related to the movement of the tongue during mastication in Japanese Azuma mole.

Animals↗
PubMed1999

Radiological demonstration of gastroesophageal reflux. Diagnostic value of barium and bread studies compared with 24-hour pH monitoring.

PURPOSE: To correlate gastroesophageal reflux (GER), demonstrated by a radiological method using food, with the reflux events, as determined by 24-h pH monitoring. MATERIAL AND METHODS: One hundred and seventeen patients with a median age of 47 years (86 male and 31 female) were examined. In the supine left position, the patient consumed 360 ml of barium contrast. Fluoroscopy was performed with the patient in the supine right oblique position during mastication and swallowing a piece of rye bread with liver pate and barium. The test was positive if barium was observed > or =5 cm proximal to the gastroesophageal junction. An antimony pH-probe was placed 5 cm above the lower esophageal sphincter, previously determined by manometry. The position was controlled by radiography after positioning and before removal. The total time of esophageal pH<4 exceeding 5.0% was considered pathological. RESULTS: The radiological method had a specificity of 100% and a sensitivity of 52% compared to 24-h pH monitoring. CONCLUSION: The high specificity of this radiological method justify direct therapeutic consequence of a positive test. However, a negative test still renders the problem unsolved.

Adolescent↗
PubMed1978

Treatment of anginose infectious mononucleosis with metronidazole.

16 patients with the anginose type of infectious mononucleosis were treated with metronidazole, and another 3 patients were given clindamycin. Most of the patients had been given penicillin or erythromycin before admittance to hospital. Treatment with metronidazole had a favourable effect on the course of the disease; the body temperature was normalized, signs of tonsillitis disappeared and cervical lymph nodes decreased in size within 3 days in 10 patients and in the remaining 6 within 4 or 5 days. Difficulty in mastication and swallowing was usually relieved within 1 to 2 days of treatment. The period before normalization was significantly shorter than in 10 controls. Two of the 3 patients who were given clindamycin developed exanthems, but otherwise a similar favourable effect as in the metronidazole-treated patients was observed.

Adolescent↗
PubMed2002

Processing and chop length effects in brown-midrib corn silage on intake, digestion, and milk production by dairy cows.

In this experiment, we evaluated the influence of increasing chop length and mechanical processing of whole-plant brown-midrib corn silage on intake, digestion, and milk production by dairy cows. Corn silage treatments were harvested at three-quarter milk line stage of maturity at 13- and 19-mm theoretical chop length without processing, or at 19- and 32-mm theoretical chop length with processing at a 2-mm roll clearance. Twenty-four multiparous Holstein cows that averaged 102 +/- 17 d in milk at trial initiation were randomly assigned to treatments in a replicated 4 x 4 Latin square design with 28-d periods. Preplanned orthogonal contrasts were used to evaluate effects of processing (19 processed vs. 19 mm unprocessed) and chop length (13 vs. 19 mm unprocessed and 19 vs. 32 mm processed). Treatments were fed in total mixed rations containing 60% forage (67% corn silage and 33% alfalfa silage) and 40% shelled corn and soybean meal-based concentrate (dry matter basis). Milk yield was unaffected by treatment. Dry matter intake was unaffected by corn silage processing, but increasing corn silage chop length reduced dry matter intake in unprocessed (26.6 vs. 25.5 kg/d) and processed (25.9 vs. 25.1 kg/d) chop length contrasts. Processing reduced milk fat content (3.36 vs. 3.11%) and yield (1.43 vs. 1.35 kg/d), increased total-tract starch digestion (92.9 vs. 97.4%), and decreased total-tract neutral detergent fiber digestion (51.0 vs. 41.8%). Total chewing time (min/d) was unaffected by treatment. Masticate mean particle length was unaffected by chop length in unprocessed and processed corn silage treatments. In this study with brown-midrib corn silage fed to dairy cows producing 43 kg/d of milk, there were no benefits from crop processing or increasing chop length on lactation performance.

Animal Feed↗
PubMed2005

Fatty acid profiles associated with microbial colonization of freshly ingested grass and rumen biohydrogenation.

Two in situ studies were conducted to examine the use of odd-chain fatty acid profiles to study microbial colonization of freshly ingested herbage in the rumen as well as fatty acid biohydrogenation. In the first study, fresh perennial ryegrass was subjected to a range of sample preparation methods before incubation in the rumen for 2 or 7 h. In the second study, fresh perennial ryegrass was chopped into 1-cm lengths and incubated in polyester bags in the rumen for 2, 8, and 24 h. After removal of bags from the rumen, 4 different washing methods, ranging from manual squeezing to machine washing, were applied. Fatty acids were extracted from washed residues and determined, as methyl esters, by gas chromatography. The main odd-chain fatty acids (with the exception of anteiso C(15:0)) were not found in fresh grass and were useful markers of the effects of incubation time, sample preparation method, and washing method on microbial colonization/contamination. The concentration of these and other odd-chain fatty acids increased with incubation time in both studies. The results indicate rapid and continued microbial colonization of freshly ingested forages, although patterns of odd-chain fatty acids did not reveal any further information about the types of bacteria-colonizing herbage. Principal component, biplot analysis provided a useful overall description of the processes of microbial colonization and degradation of plant fatty acids on fresh herbage incubated in the rumen. Bolus formation during mastication and ingestion results in extensive damage to herbage; none of the techniques (cutting, crushing, and drying/grinding) investigated in this work was able to replicate the effects of bolus formation in the animal. The study provided further evidence of loss of unfermented feed particles through polyester bag pores, especially when feeds are dried and ground. Biohydrogenation of the polyunsaturated fatty acids of fresh herbage was used principally by solid-associated bacteria to enable them to take up high levels of trans-11 C(18:1) and C(18:0) fatty acids. Although trans-11 C(18:1) was strongly associated with bacterial markers (odd- and branched-chain fatty acids), its precursor (cis-9, trans-11 C(18:2)) was not associated with bacterial variation, suggesting that its production in the rumen under these conditions was mainly extracellular.

Analysis of Variance↗
PubMed1992

Impact of stage of maturity and method of preservation of alfalfa on digestion in lactating dairy cows.

Four multiparous Holstein cows in midlactation were fed 60:40 forage:grain (dry basis) diets containing first-cutting alfalfa harvested at the early bud or early flower stage of maturity. Each of the two maturities was preserved as silage and hay. A 4 x 4 Latin square design experiment (28-d periods) was conducted to measure the impact of alfalfa maturity and method of preservation on milk production and composition, intake, digestion, digesta passage, and particle size of digesta. Milk production and composition were not affected by treatment. Increases in fiber intake resulted from increased maturity and preservation as hay, but this did not appear to limit DMI or milk production. Both increased maturity and preservation as hay resulted in the following effects in cows: more time spent ruminating, greater total chewing time, greater wet and dry rumen fill, and a greater volume of rumen contents. Rumen retention time of La applied to forage was 6 h less, and 0-h disappearance of DM from dacron bags was greater for silage than hay. In situ DM disappearance rates averaged 15%/h for silage and 9.5%/h for hay. Lag time was related inversely to 0-h disappearance. Masticates and mixed rumen samples from cows fed hay showed a greater percentage of DM as particles greater than or equal to 9.5 mm in length. Gross feed efficiency was greater for cows fed alfalfa silage than for those fed alfalfa hay, probably because of more rapid digestion and passage. The potential for rumen fill to limit intake in high producing cows appears to be greater for alfalfa preserved as hay than that preserved as silage.

Animal Feed↗