Donovan T E, Chee W W
Department of Biomaterials Science, School of Dentistry, University of Southern California, Los Angeles.
Dent Clin North Am. 1993 Jul;37(3):433-43.
The practitioner today has a number of alternative restorative modalities from which to chose when faced with the necessity of restoring posterior teeth. The primary options with extensively broken down posterior teeth are cast gold and bonded ceramic inlays, onlays, and partial veneer restorations. The dentist and informed patient should make the choice of which modality is appropriate based on a number of criteria. Certainly, based on the criteria of basic physical properties, potential for marginal integrity and stability of that integrity, cast gold is the material of choice. In terms of conservation of tooth structure and systemic biocompatibility, both restoration types are excellent. With regard to effects on long-term pulpal health, much remains unknown with many of the materials used with bonded restorations at the present time. Conservative cast gold restorations have proved to be very successful in this regard over the long term. The potential for tooth strengthening with bonded restorations is certainly an exciting, but as yet, unproven, clinical reality. Thus, until those clinical data are available, the most predictable means of restoration of extensively broken down posterior teeth is with partial-coverage cast gold, protecting cusps at risk as required (Fig. 9). As mentioned previously, cast gold inlays are also a very conservative and predictable restoration (Fig. 10). Both cast gold and bonded ceramic restorations are technically demanding, but the details required to produce excellent gold castings are well defined, and can be learned readily. Much remains to be learned regarding the materials and the techniques used to fabricate bonded ceramic restorations. Priority issues would seem to be reaching a consensus regarding the details of tooth preparation and the development of improved luting resins with improved wear resistance. Simplified techniques to improve the quality of the fit of these types of restoration also are of paramount importance. The requirement for an esthetic, or, more properly, use of a tooth-colored restoration in a posterior tooth, should be evaluated carefully for each individual restoration. Often it is possible to restore a tooth with cast gold with minimal or no display of metal. The patient will then receive the long-term benefit of cast gold and not compromise on esthetics. It is our obligation as diagnosticians to educate our patients so that they are in a position to choose, when indicated, this most cost effective of restorative options.
如今，从业者在面对后牙修复的必要性时，有多种可供选择的修复方式。对于严重破损的后牙，主要的选择是铸造金修复体以及粘结陶瓷嵌体、高嵌体和部分贴面修复体。牙医和了解情况的患者应根据多项标准来选择合适的修复方式。当然，基于基本物理性能、边缘完整性的可能性以及该完整性的稳定性等标准，铸造金是首选材料。在保存牙体组织和全身生物相容性方面，这两种修复类型都很出色。就对牙髓长期健康的影响而言，目前许多用于粘结修复的材料仍有很多未知之处。长期来看，保守的铸造金修复体在这方面已被证明非常成功。粘结修复体增强牙齿的潜力固然令人兴奋，但目前仍是未经证实的临床现实。因此，在获得这些临床数据之前，修复严重破损后牙最可预测的方法是采用部分覆盖的铸造金修复体，并根据需要保护有风险的牙尖（图9）。如前所述，铸造金嵌体也是一种非常保守且可预测的修复方式（图10）。铸造金修复体和粘结陶瓷修复体在技术上都要求很高，但制作出色的金铸件所需的细节已明确界定，且很容易掌握。关于用于制作粘结陶瓷修复体的材料和技术，仍有很多需要学习的地方。首要问题似乎是就牙体预备细节达成共识，并开发出耐磨性更好的粘结树脂。提高这类修复体贴合度质量的简化技术也至关重要。对于每一个具体的修复病例，都应仔细评估在后牙使用美观修复体（或者更确切地说，使用与牙齿颜色相近的修复体）的需求。通常，用铸造金修复牙齿时，可以将金属暴露降至最低或完全不暴露。这样患者既能获得铸造金修复体的长期益处，又不会在美观上有所妥协。作为诊断医生，如果有必要，我们有责任告知患者，以便他们能够选择这种最具成本效益的修复方案。
