US2243377A - Set of false teeth - Google Patents

Description

' May 27, 1941.

L. HALLER 2,243,377

SET OF FALSE TEETH Filed July 11, 1939 Patented May 27, 194i UN-i'iiifi star E S "series Application July 11, 1939, Serial No. 283,848 In Germany September 5, 1938 1 Claim.

In the known sets of false teeth it occasionally happens that the jaw plates shift both when the wearer is chewing also when he is speaking. This objection is particularly apparent when the anatomic structure of the mouth is unfavourable or the set of artificial teeth is not accurately fitted to the shape of the jaw. Then, the chewing surfaces of the teeth do not meet properly which detracts from the value of the set of artificial teeth in use. Furthermore, any natural teeth to which the set of artificial teeth is secured become less durable on this account owing to overstressing,

The present invention relates to a set of artificial teeth which overcomes the above mentioned objections.

Sets of artificial teeth are known whose masticating surfaces are serrated. The object of this measure is, to ensure that the teeth accurately interengage when chewing, but this object is not attained owing to the slight height of the sawlike raised portions. Moreover, the teeth have an extremely ugly appearance because all the teeth are shaped like a saw tooth.

This objection is overcome by the set of artificial teeth according to the invention. It is characterized in that two or more of the rear upper and lower molars limit the movements of the jaw, when chewing, by means of intermeshing protuberances and depressions and bring the jaws into the closed biting position. Thus, if a plate of the set of artificial teeth shifts its position when the mouth is being opened or when chewing, this plate is returned into its normal and correct position because the rear molars provided with protuberances and depressions come into engagement before the masticating surfaces of the other teeth meet, with the result that accurate articulation of the set of artificial teeth is attained. Moreover, as the set of artificial teeth is held in its correct position, a better chewing pressure is obtained, If the lower jaw, has natural front teeth besides the artificial molars, and if pressure is exerted on the upper front teeth, which is taken up by the artificial teeth extending along the rear side of the lower front teeth and transmitted to the last molar of the lower set of teeth, the pressure being taken up by the last molar of the upper set of teeth which engages over the last molar of the lower set of teeth.

The artificial and natural teeth in rthe lower jaw are held together by the upper set of teeth like a vault. This causes an increase in the chewing force and considerably saves the natural teeth. Another advantage is that the visible teeth have an absolutely normal shape correv sponding to that of the natural teeth.

Two embodiments of the invention are illustrated by way of example in the accompanying drawing, in which:

Fig. 1 shows in front elevation an upper and a {lower row of artificial teeth of a set of artificial teeth in flattened state,

Fig. 2 shows in side elevation an upper and a lower row of artificial teeth before the chewing surfaces meet,

Fig. 3 is a side elevation with the rows of artificial teeth in contact,

Fig. 4 is a side elevation of a modified form of construction.

The set of artificial teeth consists in known manner of the gum plates h and i in which the artificial teeth are fixed. According to the drawing the rear molar teeth a, b are provided with surfaces sloping upwards from the outer towards the inner side so that depressions y are formed between the two molars a and b. The lower molars c, d are inversely constructed with upwardly sloping surfaces from the outer side towards the inner side so that protuberances f are formed. When the mouth or the set of teeth is closed, the protuberances of the lower molars c, d engage in the depressions g of the upper molars a, b. The protuberances of the lower row of teeth are made of such a height that, as the set of teeth is being closed, they engage in the depressions g before the rows of teeth is, Z meet (Fig. 2). If one row of teeth should shift when the mouth is being opened or when chewing, this is returned into its normal or correct position relatively to the other with the result that accurate articulation of the chewing surfaces of the teeth is attained (Fig. 3)

The protuberance joints e may be each formed of three pairs of molars instead of two pairs of molars a, b and c, 0? (Fig. 4) The depressions g may also be formed in the lower molars c, d and the protuberances f by the upper molars a, b. The rows of teeth k, 1 arranged between the molars a, a and c, c are formed of teeth with ordinary chewing surfaces with the result speaking and chewing takes place in the normal manner. Furthermore, the set of artificial teeth is of good appearance.

The molars which are constructed as depressions and protuberances, may be made in a shape which is either similar or dissimilar to a tooth. The molars used to form the protuberances and depressions may also be made in one piece. The

molars a, b and c, d may be of porcelain, metal or any other suitable material,

The new arrangement is equally suitable for full sets of artificial teeth for toothless mouths and also for partialsets if there are natural teeth between the artificial teeth.

I claim: e

A set of artificial teeth comprising at least two rear upper molars and two complementary rear lower molars, each of said molars having a fiat smooth slanting occlusal face extending in a single plane from front to rear of said tooth, the slope of the occlusal faces of the two upper molars being slanting or oppositely directed mesiodistally to define a V-shaped configuration from the buccal aspect and the slope of the occlusal faces of the two lower molars being oppositely directed to define a complementary V-shaped configuration from the buccal aspect; the apices of the so defined Vs being at the interdental spaces of the pairs of molars in each case, whereby the interdental spaces of the two pairs of molars are brought into vertical alinement when the set of artificial teeth is brought into occluding relation.

LUDWIG HALLER.

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