Dougherty H L, Beazley W W
Am J Orthod. 1976 Nov;70(5):505-16. doi: 10.1016/0002-9416(76)90275-x.
A review of the literature, both scientific and commercial, did not demonstrate the separation of the inner and outer bows into a biodifferential interchangeable system. The prime design idea, to separate the inner and outer bows, increased versatility and yielded a multiple appliance with a greater range of use and safety. The joint couple systems could be adapted to fulfill the criteria cited in the literature during preliminary treatment (deciduous dentition), partial treatment, full-banded treatment, and retention. The biodifferential design was compatible with most mechanical orthodontic appliances and systems currently used. The three joint designs presented and the three inner bow lock devices fulfilled the parameters expected from the normal use of the present face-bow in necessary strength, stability, and use. Further, the use of a joint couple between the inner and outer bows expanded the versatility of the face-bow into a biodifferential system and allowed for an easily manageable and orderly change of forces, vectors, sizes, and shapes requiring little chair time and minimum instruction to the patient. The inner bow could be used as an intraoral appliance for bumpers, shields, and oral screens. These easily made, preformed, interlocking parts could be marked or color coded as to type and size and keyed, grooved, and designed to prevent inverted interlocking of parts. The inner bow could be tied in, as an aid in patient cooperation, or the inner and outer bows could be pinned or ligated together to prevent separation. One of the most important factors of the biodifferential system is protection of the patient from severe trauma to the eyes, face, and mouth due to misuse or accident, as has occurred in the one-piece face-bow. The biodifferential system fulfills the five criteria of the investigation: (1) a system of interchangeable, interlocking joint parts, (2) safety and dependability, (3) easy changes in force, vectors, and moments, (4) enhanced patient cooperation, and (5) oral hygiene.
对科学及商业文献的回顾未表明内弓和外弓能分离成生物差异可互换系统。将内弓和外弓分离的主要设计理念增加了通用性，并产生了一种用途范围更广且更安全的多功能矫治器。联合耦联系统可进行调整，以满足文献中在初步治疗（乳牙列期）、部分治疗、全带环治疗及保持阶段所提及的标准。生物差异设计与目前使用的大多数机械正畸矫治器和系统兼容。所展示的三种联合设计以及三种内弓锁定装置在必要的强度、稳定性和使用方面满足了当前面弓正常使用所期望的参数。此外，在内弓和外弓之间使用联合耦联将面弓的通用性扩展到了生物差异系统，并允许轻松管理和有序改变力、矢量、大小和形状，所需的诊疗时间很少，对患者的指导也最少。内弓可用作口内矫治器，用于制作缓冲器、防护板和口腔屏障。这些易于制作、预制且相互锁定的部件可按类型和尺寸进行标记或颜色编码，并设有键槽、开槽并进行设计，以防止部件反向互锁。内弓可系入以帮助患者配合，或者内弓和外弓可通过销钉或结扎固定在一起以防止分离。生物差异系统最重要的因素之一是保护患者免受因误用或意外导致的眼睛、面部和口腔严重创伤，一体式面弓就曾出现过此类情况。生物差异系统满足了研究的五项标准：（1）可互换、互锁的联合部件系统；（2）安全性和可靠性；（3）力、矢量和力矩的轻松改变；（4）增强患者配合度；（5）口腔卫生。
