Complete Dentures

A digital-based curation of articles from the Journal of Prosthetic Dentistry

Diagnosis & Treatment Planning

The “neutral zone” concept focuses on designing a denture within a space that synergistically functions with the surrounding oral anatomy and structures such that outward forces imparted by the tongue are neutralized by inward forces from the cheeks and lips. The article describes how a “neutral zone” denture achieves stability by its cameosurface design’s balance with horizontally-directed forces and how that principle requires the reversal of the order in the denture fabrication technique that focuses on developing external contours rather than the intaglio and occlusion-related surfaces.

Impression Techniques

This article describes the qualities of polysulfide rubber impression material with regard to dimensional stability over time from mixing, polymerization, post-impression storage, and stone cast pouring. Considerations for how to use polysulfide effectively for impression making are reviewed - including custom tray design parameters, application of tray adhesive, mixing of material, how to border mold and make wash impressions for complete and partial removable dentures.

The “lingual impression position” impression technique is described to accurately record the anterior region of the resorbed mandibular residual ridge. A custom tray handle on the impression tray is used to guide the tongue during the impression making process. The border molding of the anterior lingual region by the genioglossus muscle and sublingual glands, becomes the lingual guiding ramp for the tongue so that it is positioned to stabilize the denture.

CAD-CAM

Traditional denture impression techniques require some amount of pressure application at the time of impression making that can yield an inaccurate record of moveable tissues. This dental technique article describes how to integrate intraoral scanning to record an edentulous ridge with hard tissue resorption and highly mobile unsupported soft tissue with minimal distortion.

Denture Design Theory

Posterior Palatal Seal

Denture Fabrication Techniques

Esthetics

Conventional (Analog)

Analog-Digital Hybrid

CAD-CAM

The retention of CAD-CAM denture bases that were produced by subtractive milling of pre-polymerized PMMA versus heat-polymerized bases are compared in this article. All impressions were made using analog techniques with conventional impression materials. The impression was first scanned for CAD-CAM denture base fabrication and then poured in stone for conventional denture processing. A force transmission device measured the retention of the different bases while exerting vertical dislodging forces through a pulley system at timed intervals.

A full digital workflow for making complete dentures can maximize the ease and time efficiency of treatment, however intraoral scanning lacks the functional border molding that provides peripheral sealing required for retention – a key factor in denture utility. This article’s study patients completed an intraoral scan and conventionally border molded impression of the maxilla. The physical impressions were poured and their casts were digitized. The intraoral scan and the scanned cast were used to fabricate a set of milled and printed dentures bases. The resulting denture bases from both workflows were scanned and their intaglio forms were digitally compared to the original digital intraoral and cast scans. Retention was clinically assessed at the post dam and tuberosity regions with a dynamometer that measured the force of dislodgement.

Reline & Rebase

Clinical Application

Occlusion

Complications & Complex Cases

A full digital workflow for making complete dentures can maximize the ease and time efficiency of treatment, however intraoral scanning lacks the functional border molding that provides peripheral sealing required for retention – a key factor in denture utility. This article’s study patients completed an intraoral scan and conventionally border molded impression of the maxilla. The physical impressions were poured and their casts were digitized. The intraoral scan and the scanned cast were used to fabricate a set of milled and printed dentures bases. The resulting denture bases from both workflows were scanned and their intaglio forms were digitally compared to the original digital intraoral and cast scans. Retention was clinically assessed at the post dam and tuberosity regions with a dynamometer that measured the force of dislodgement.

This article elaborates on a common challenge with patients who may benefit from denture therapy – gagging. The gag reflex in its severe form can be a significant barrier to seeking and receiving dental care. Anatomical, physiological, and psychological aspects in gagging are reviewed. Management strategies like desensitization, training, and sedation are discussed for clinical application in patients with gagging.

Head and neck cancers may require radiotherapy to the oral cavity. This classic article reviews how short and long-term radiation therapy sequelae to the oral mucosa, saliva, and other anatomic structures of the mouth affect the diagnosis and planning, treatment, and maintenance of complete dentures.

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