Short-term and long-term effects of chewing training on occlusal perception of thickness.

The aim of this study was to investigate the short-term and long-term effects of functional stimuli, induced by intense chewing and by prolonged systematic chewing training, on the response of occlusal perception of thickness. The material comprised 25 young adults divided into an experimental group (17) and a control group (8). The occlusal perception of thickness was tested by successively placing different thicknesses of aluminum foil between five pairs of occluding teeth, i.

Characteristics of mandibular masticatory movement in young and elderly dentate subjects.

Dimensions and velocity of mandibular movement are important variables in the evaluation of masticatory and speech patterns. However, little information is available concerning elderly dentates and their oral motor function and behavior. Double recordings of a chewing period, from start to swallowing, were performed in 14 elderly (mean age, 80 years) and 30 young (mean age, 26 years) dentate subjects chewing crispbread.

Sequential 5-fluorouracil and leucovorin in patients with advanced symptomatic gastrointestinal cancer.

50 patients with advanced symptomatic gastrointestinal cancer were treated with sequential 5-fluorouracil (5-FU)/leucovorin. Patients received an intravenous bolus injection of 5-FU (500 or 600 mg/m2) and leucovorin 30-40 min later, either 50 mg (41 patients) or 200 mg (9 patients). Treatment was given in repeated courses either once weekly or on 2 consecutive days every other week until progression.

Background factors in craniomandibular disorders with special reference to general joint hypermobility, parafunction, and trauma.

Seventy-four female patients referred to a CMD clinic were randomly selected for an examination of general joint mobility according to Beighton. Thirty of the patients (41%) were classified as hypermobile. Eighty-three percent of the patients with generally lax joints had TMJ involvement in comparison to 41% of the patients with no joint laxity.

Prevalence of signs and symptoms of dysfunction in the masticatory system: an epidemiologic study in an adult Swedish population.

The prevalence of signs and symptoms of dysfunction in the masticatory system was studied by questionnaire and clinically in a randomly selected age- and sex-stratified sample of Swedish adults as a part of an epidemiologic survey on oral health. The prevalence of dental wear was also registered. There were 920 subjects examined, representing a participation rate of 95%.

Prevalence of signs and symptoms of craniomandibular disorders in tinnitus patients.

One hundred two tinnitus patients were examined to determine the prevalence of signs and symptoms of CMD. The examination comprised determination of the anamnestic and clinical dysfunction indices according to Helkimo; assessment of the dentition, occlusal factors, and signs of parafunctions; and accomplishment of a tension test. Patients also answered a questionnaire concerning the presence and frequency of CMD symptoms and headaches, as well as influence on tinnitus by mandibular movements, by pressure applied to the TMJ, or by dental therapy.

Cinefluoroscopic study of long-term changes of bolus position and chewing cycle duration after fixed prosthetic treatment.

Some chewing parameters were studied in 12 patients with a complete maxillary denture and a 12-unit fixed mandibular denture anchored to the two canines. Registration by means of fluoroscopy were made before, 1 month after, and in four patients 13 yr after treatment. The mean velocity of the mandible during chewing increased after the prosthetic treatment and remained stable for meat during the observation period.

Effect of chewing training on masticatory efficiency.

A special, hard chewing gum was used to study the effects of chewing training on masticatory efficiency. An experimental group of 17 individuals used this chewing gum 1 h daily for 28 days, while a control group of 8 individuals performed no chewing-gum training. The percentage of masticatory efficiency was measured with a special sieve system, and the time for 10 chewing cycles was taken from EMG recordings.

Effect of chewing training on mandibular postural position.

The inter-occlusal rest space (free-way space) was studied before and after short and long periods of chewing of a hard resin in 15 healthy subjects. During a month of daily training for one hour of chewing no significant changes in the interocclusal rest space were seen. After 30 min of intense chewing the mean interocclusal distance increased to about twice its original size.

Recording of masticatory mandibular movements and velocity by an optoelectronic method.

In an assessment of the reproducibility of three-dimensional masticatory movements by an optoelectronic method, the tests conducted on the same individuals at different times produced results that were almost identical. However, some significant differences were found in the mandibular movement parameters when the subjects chewed different foods. This was mainly reflected in a longer opening time and higher values for the traversed 3D distance during mastication of chewing gum compared to peanuts.

Dietary pattern, energy and nutrient intake in patients with oro-facial discomfort complaints.

In ninety-six patients with oro-facial and general complaints, which the patients assumed were caused by galvanic currents and/or metallic restorations, the recording and analysis of dietary pattern, energy and nutrient intake were performed. The records, in household measures, of the intake of food and beverages during 7 consecutive days according to a written instruction were collected. Sixty-eight out of the ninety-six records were sufficiently complete for calculation of nutrient intake.

Extensive fixed partial dentures on mandibular canine teeth: a 5-year recall study.

Twelve patients were followed for 5 years after treatment with a 12-unit cantilever fixed partial denture on the mandibular canines opposed by a complete maxillary denture. Two fixed dentures had to be removed, one because of an abutment tooth root-fracture and one because of rapid marginal bone loss in a terminal stage of leukemia. Caries and periodontal lesions were rare, but other complications, principally related to endodontics, occurred.

Biting forces in patients with craniomandibular disorders.

Treatment for 10 female patients having craniomandibular disorders of neuromuscular origin showed a reduction in dysfunctional symptoms and improvement in their condition. In response to treatment, a standardized recording method was used to measure alterations to bite force values. In about 60 percent of categories representing various positions in the dental arch from which maximal and submaximal biting forces were measured, there was significant variation between replicate registrations.

Measurement of absolute energy spectra from a clinical CT machine under working conditions using a Compton spectrometer.

Absolute measurements of photon energy spectra (keV-1 sr-1 mA-1 s-1) from a clinical CT machine have been performed under normal working conditions (140 mA tube current) using a Compton spectrometer. The inaccuracy of the measured spectra is estimated to be +/- 6%, determined by uncertainties in dead-time corrections and in the parameters of the geometrical set-up. Absorbed doses measured in thermoluminescent LiF dosimeters agree within this uncertainty with calculated ones derived from measured spectra (80 kVp, 120 kVp and 140 kVp) and tabulated mass energy absorption coefficients for LiF.

Compton spectroscopy in the diagnostic x-ray energy range. II. Effects of scattering material and energy resolution.

The overall performance of a Compton spectrometer and, in particular, its energy resolution are investigated both experimentally and theoretically for different scattering materials. Using low-Z (less than or equal to 8) scatterers of moderate sizes (scatterer diameter d less than or equal to 5 mm), there are negligible disturbances due to coherent and/or multiple scattering at 90 degrees scattering angle and photon energies above 20 keV. Two factors contribute to decreasing the energy resolution compared with that in direct measurements: (i) the velocity distribution of the electrons in the scatterer and (ii) the scattering geometry.

Compton spectroscopy in the diagnostic x-ray energy range. I. Spectrometer design.

The optimal design of a Compton spectrometer for measuring photon energy spectra from x-ray tubes in a clinical laboratory is analysed. The demands are: (i) coherent and multiple scattering distort the measurements and must be avoided; (ii) the measuring time should be as short as possible to avoid unnecessary wear on the x-ray tube; and (iii) the impairment in energy resolution due to the scattering geometry should be kept minimal. A scattering angle of 90 degrees is advocated.

Effect on liver tumor growth in rats of allopurinol and 5-fluorouracil in combination with hepatic artery ligation.

Rats with an experimental solitary liver tumor of a nitrosoguanidine-induced colonic adenocarcinoma were subjected to hepatic artery ligation (HAL) alone or in combination with 5-fluorouracil (5-FU) in three different doses, with or without the addition of allopurinol. The drugs were injected i.p.

[Effect of chewing training on the postural position of the mandible].

The aim of this project was to study possible effects of chewing gum training on the postural position of the mandible. The material consisted of 11 male and 14 female dental students which were divided in to an experimental and a control group. The subjects were thoroughly informed about the experiment and participated voluntarily.

Perception of jaw position during different conditions.

The perception of jaw position, measured as the ability to produce a predetermined mandibular posture repetitively, was recorded under different experimental conditions. A control group of asymptomatic subjects was tested before and after anesthesia of the TMJs and after fatigue of the masticatory muscles. Groups of patients with craniomandibular disorders of arthrogenic or myogenic origin were also tested.

Blood-flow and metabolic response in a contracting canine masticatory muscle.

The mechanical and metabolic characteristics of the canine masseter muscle of seven adult dogs, aged 3 years, weighing 45-55 kg, were evaluated by electrically provoked contractions. The masseter muscle was exposed by careful surgery and stimulated by two silver electrodes placed in the anterior and posterior aspects of the muscle. The bite force was measured with a force transducer.

Endoscopic surveillance of patients following a curative resection for colorectal cancer.

From 1974 to 1985, 161 patients were followed by at least one colonoscopy following a polypectomy for an adenomatous polyp. These patients had had a previous curative resection performed for colorectal carcinoma. The median follow-up time after surgery was 54 months.

Mandibular bone resorption in patients treated with tissue-integrated prostheses and in complete-denture wearers.

Mandibular bone resorption was studied in patients treated with tissue-integrated prostheses (TIP) and in complete-denture wearers by distance and area measurements on cephalometric radiographs. The area measurements were performed by means of a computer. Two TIP groups with short and long periods (mean = 2.