Joseph J. Massad

The neutral zone revisited: From historical concepts to modern application

Providing complete denture therapy to patients with atrophic residual alveolar ridges is challenging. Because these patients suffer ongoing diminution of the denture foundation, modern approaches often involve dental implant therapy as a means of improving the denture foundation and supplementing the mechanics of prosthesis support, retention, and stability. Regardless of implant availability, physiologically optimal denture contours and physiologically appropriate denture tooth arrangement should be achieved to maximize prosthesis stability, comfort, and function for patients. This article presents historical perspectives on the arrangement of denture teeth in the facial-lingual dimension and the contouring of complete denture polished surfaces. Additionally, a modern clinical technique is presented for the physiologic registration of denture tooth positions and denture base contours. Information gained may then be incorporated into definitive prostheses in an effort to achieve successful complete denture therapy.

A metal-based denture with soft liner to accommodate the severely resorbed mandibular alveolar ridge

A technique is described for designing and making a mandibular denture, for patients with severely resorbed and compromised residual alveolar ridges. The denture base is stabilized by a mucostatic impression technique, myostatic denture base design, weight of a cast metal denture base, and noninterceptive occlusion with monoplane or Centrimatic posterior teeth. The hard metal denture base is made tissue-compatible by means of a soft denture liner attached to a specially relieved cast metal denture base. Over a 2-year period, this technique has successfully provided, in my practice, an alternative to residual alveolar ridge implants and other surgical interventions for 22 edentulous patients with severely resorbed and compromised mandibular residual alveolar ridges.

Subcrestal Implant Placement and Recontouring Soft Tissue Using the Erbium YAG Laser to Manage Restorative Space in Implant Overdentures: Recontouring Soft Tissue for Restorative Space

Subcrestal implant placement helps gain vertical restorative space at the location of the implants; however, this leads to the development of a tall mucosal cuff, necessitating the use of tall abutments. This article describes the technique of gaining restorative space by decreasing the height of the mucosal cuff with an Erbium YAG laser.

A Prosthesis Retention System for Full-Arch, Fixed, Implant-Supported Prosthesis: Retention System for Fixed Implant Prosthesis

Full-arch, fixed, implant-supported prostheses can be designed to be cement- or screw-retained. Both retention mechanisms have a few inherent disadvantages. A fixed attachment system has been introduced to circumvent the disadvantages of both screw and cement retention. This system eliminates the screw access holes and the use of cement. The number of intraoral procedures required is also reduced. The purpose of this article is to report a case using the Locator F-Tx Attachment System to facilitate fabrication of an esthetic, clinician-retrievable, full-arch implant-supported fixed dental prosthesis.