. The science and practice of dental surgery. is made early enough;\arney E. Barnes (21) also considersseparation possible, but the excel-lent radiographs that he has pub-lished seem to show separation ofthe pre-maxillary suture chiefly orentirely. Pullen (134) gives a goodsummary of different methods ofseparation adopted and the resultsproduced; and Wright (173) de-scribes an interestmg appliance formeasuring the internal width ofthe nose between the walls of themaxillary sinus. Anchorage.—So far, the effects ofthe application of force to a toothand various means of applying ithave been consi
. The science and practice of dental surgery. is made early enough;\arney E. Barnes (21) also considersseparation possible, but the excel-lent radiographs that he has pub-lished seem to show separation ofthe pre-maxillary suture chiefly orentirely. Pullen (134) gives a goodsummary of different methods ofseparation adopted and the resultsproduced; and Wright (173) de-scribes an interestmg appliance formeasuring the internal width ofthe nose between the walls of themaxillary sinus. Anchorage.—So far, the effects ofthe application of force to a toothand various means of applying ithave been considered ; but accordingto Newtons third law, To everyaction there is an equal and con-trary reaction ; and the variousappliances used for movmg teethare all designed with reference towhat is miscalled anchorage . Asimple example of reaction is found m theinclined plane previously referred to. The forceof occlusion is met by an equal reaction fromthe inclined plane having vertical and horizontalcomponents, but the physiological conditions are. Fig. 252.—Period between A and B, three weeks. (F. M. Willis : Dental Cosmos.) such that the effect of the force is spent entirelyon the occluding teeth, the inclined plane ofmetal or vulcanite being immovable ; the verticalcomponent drives the teeth into their socketsand the horizontal component forces them back-wards. There is no such thing as anchorage inthe proper sense of the w-ord. In the anchoring 155 of a iship, a movable thing (the ship) is madestationary by being attached to a fixed thing(the sea bottom or the anchor embeddedin it). On the other hand, a tooth, com-paratively a fixture, is to be moved by a
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectdentistry, bookyear19
