Gifu Shika Gakkai zasshi = The Journal of Gifu Dental Society最新文献

Achievement of best balance and facial harmony is the main goal of orthodontic treatment, and it is especially important to retract the lip in case of maxillary protrusion. A 11-year and 7-months-old girl was first seen with chief complaints of maxillary protrusion. We extracted 4/4 4/4, treated the patients with the Vari-Simplex-Discipline for 43 months, and evaluated changes in facial profiles. We found, that excessive lip protrusion was eliminated and good interdigitation obtained. In addition to, angle ANB and overjet were corrected to ideal conditions.

The major constituent free fatty acid in rat parotid and submandibular glands was palmitic acid (about 40% of the total), followed by saturated and unsaturated fatty acids with 18 carbon atoms and arachidonic acid. The composition was changed by chronic administration of isoproterenol, with an increase of linoleic acid and a decrease of arachidonic acid coinciding with changes in the acyl composition of phospholipids. With respect to the metabolism of unsaturated fatty acids, delta 6-desaturation activity converting linoleic acid to gamma-linolenic acid was detected using [14C]linoleoyl-CoA in the submandibular gland. These results suggest that changes in the acyl composition of phospholipids induced by chronic administration of isoproterenol are in part due to changes in free fatty acid composition and that delta 6-desaturation activity may be involved in the regulation of unsaturated fatty acid composition.

Carrageenin paw edema of rats was inhibited in a dose-dependent manner by subcutaneous administration of polyamines. The latter had to be administered at least 2 hr before carrageenin challenge to achieve such inhibition. Moreover, inhibition was blocked by the simultaneous injection of actinomycin D. Polyamines also inhibited local bluing reactions to histamine in rats and similarly had to be administered 3 hr previously to achieve inhibition. Polyamines were shown to be glucocorticoid-type anti-inflammatory drugs, and may be glucocorticoids mediators of the synthesis of the postulated vascular permeability inhibitory protein that do not inhibit phospholipase A2 activity. Neutrophil chemotaxis was inhibited by polyamines in a concentration-dependent manner. In contrast to the experience with carrageenin paw edema, simultaneous addition to actinomycin D did not block the inhibitory action of polyamines on neutrophil chemotaxis. These results suggest that polyamines possess at least 2 different anti-inflammatory mechanisms. The first is mediated by the synthesis of an anti-inflammatory protein, and the second consist of direct action on leukocytes.

The effects of unilateral facial nerve denervation on the facial growth were studied by physiological and by histochemical examinations, using four- week- old Wistar rats. Two hundred twenty rats were divided into three groups: a control group, a group of subjects which resection of the left facial nerve, and a sham operation group. The rats were killed 1, 5, 10, 30, 60, 90, 120 days later. The superficial and deep masseter muscle fibers on both sides were classified into type I and type IIA or IIB on the basis of myosin ATPase activity and the diameter of these fibers was measured. The masseter muscles were stained with H&E and NADH-TR. Electromyogram recordings were analyzed during the rest position, stretch reflex, voluntary action and eating of solid foods in half of all groups. (1) The face of rats after denervation deviated to the right side, and the maxillo-facial skeleton was affected from the 30th day. (2) In the denervation groups the right side showed higher action potentials than the left side. (3) In the deep masseter muscles near muscle spindle in the denervated groups, the percentage of type I fibers on the right side increased on the 90th day, and that of type IIA fibers decreased on the 30th day. (4) The diameter of the deep masseter muscle fibers, of type I, IIA and IIB increased on the right side. These results prove that facial nerve denervation led to a functional disorder and a transformation of growing direction.

Hydroxyapatite (HAp) and alpha-Tricalcium phosphate (alpha-TCP) are generally known as materials biocompatible to human tissue. In this study, the adaptation of HAp and alpha-TCP as a pulpotomy agent was studied histopathologically. In this study, HAp granules with a sintering temperature of 1,200 degrees C and sieved through a 37 micron sieve, and APATITE LINER TYPE I (Sankin CO.) as alpha-TCP were used. Calcium hydroxide served as a control. The physical properties of these experimental materials were evaluated and the reaction of pulp tissue to the materials was examined histolongically in dogs. alpha-TCP mixed with saline solution showed more homogeneous and higher viscosity than HAp mixed with saline solution. When alpha-TCP was applied on the site of exposure of a pulp following pulpotomy, the mechanically harmed pulp tissue was healed earlier than when HAp was applied. A hard tissue was formed earliest when calcium hydroxide was used, and then in the order of alpha-TCP and HAp. When HAp was applied, osteodentin was formed and when alpha-TCP was applied, dentin was formed on the site of exposure of a pulp following pulpotomy. When HAp or alpha-TCP was applied, the calcification in the initial stage was not observed. The calcification in initial stage was observed when calcium hydroxide was applied. These results suggest that alpha-TCP is useful as a pulpotomy agent.

The purpose of this study was to determine the amount and direction of nasal growth, before or during orthodontic treatment. However, the growth of the nose as a separate entity in relation to classification of cranio-facial type has not been investigated by the lateral roentgenographic cephalogram until recently. In this study, I used 2782 traces of lateral roentgenographic cephalograms to study the growth of the Japanese nose. The traces were derived from a cross-sectional study of 1,233 growth of the Japanese nose. The traces were derived from a cross-sectional study of 1,233 males and 1,549 females over 5 years and 6 months old who had not undergone the orthodontic treatment yet. Various nasal parameters were measured to study the growth of 6 linear, 2 angular nasal parameters and 1 sectional area of the external nose. The early growth in females and late growth in males were the presence of an adolescent growth spurt and the height of the maxillary prognathic type on the nasal bone and the nasal tip were longer than that of the maxillary retrognathic type. Therefore, in orthodontic treatment, the growth of the cranio-facial type should be taken into consideration before the use of orthognathic force or orthognathic surgery.

The fluoride concentrations of ammonium fluoride solution (NH4F,pH 4.4), which has the same effect on enamel powder as conventional APF solution, were studied. Human enamel powder (200 mesh passed) was treated with solutions of NH4F (1,000 ppmF-, 3,000 ppmF-, 5,000 ppmF-, 7,000 ppmF-, 9,000 ppmF-, pH 4.4) and APF (9,000 ppmF-, pH 3.4) for 5 min. at 37 degrees C. Some of the specimen was washed with 1MKOH solution for 48 hours. Fluoride uptake by enamel powder was analyzed by means of chemical analysis and reaction products identified using X-ray diffractometry. The fluoride uptake of 5,000 ppmF- of NH4F-treated enamel was the same as that of APF-treated enamel. X-ray diffractometry showed that CaF2 was formed in the experimental groups. CaF2 with high crystallinity was formed in the NH4F-treated enamel, and the peak height of X-ray diffraction pattern of CaF2 in 3,000 ppmF- of NH4F-treated enamel was the same as that of APF-treated enamel. In conclusion, the ammonium fluoride solution of 3,000-5,000 ppmF- had a similar effect on enamel powder as conventional APF solution.

The statistics for prosthetic restorations used for missing teeth at the Prosthetic Department of Asahi University Hospital from April 1986 to March 1987 were compared with those obtained for an earlier period (April 1983 to March 1984). Fixed bridges and removable partial dentures constituted the majority of the prosthetic restorations for posterior teeth. Fixed bridges were twice more frequently used for anterior teeth during this period than during the previous period. For a single missing tooth, fixed bridges amounted to 90% and removable partial dentures to 10%, as they did in the previous period. For two or more missing teeth, the use of fixed bridges was some what increased compared to the previous period. As in the previous report, the use of so-called one-tooth denture was most frequent for missing lower first molar. For bridges, the average number of missing teeth and that of abutment teeth were 1.3 and 2.4 respectively. Bridges for one missing tooth with two abutment teeth were most frequently used. For removable partial dentures, the average number of missing teeth and that of abutment teeth were 6.1 and 2.8 respectively. Removable partial dentures for two missing teeth with two abutment teeth were most frequently used. Full cast crowns were most frequently used for bridge retainers, followed by facing crowns. Facing crowns were used more than twice as frequently during this period as they were during the previous period.(ABSTRACT TRUNCATED AT 250 WORDS)

Pure titanium produced by a commercial pure titanium casting system was studied for use as a cast plate for clinical application. The mechanical properties, elemental analysis, castability, adaptability of pure titanium and adhesion to denture base resin were investigated. The interfacial zone of the pure titanium castings was composed of a layered structure obtained by reaction with phosphate bonded Al2O3/SiO2 investment material. Vicher's hardness at 100 microns thick from the surface was higher than that in the inner part by oxidation. Cast pure titanium showed tensile strength, elongation and hardness close to those of the type III or IV dental gold alloy. The castability of pure titanium was lower than that of Co-Cr alloy and pure titanium castings also had large casting defects. Adaptability between pure titanium cast plate and the working model was satisfactory when reversible hydrocolloid impression material was used with heating-bath treatment in the refractory model. The tensile and compressive shear bonding strength of pure titanium to heat-curing or self-curing resin were similar to that of the Co-Cr alloy, and surface treatment using a solution containing 2-vol% 3-methacryloxypropyltrimethoxysilane produced a higher bonding strength than non-treatment, MKV treatment and 4-META treatment. These findings suggest that pure titanium castings produced by this system have suitable mechanical properties, adaptability and adhesion to denture base resin, and is available for cast plate in clinical application.