The effect of thyrocalcitonin and growth hormones on bone metabolism.

The use of the hormone, thyrocalcitonin, has been shown to change the bone metabolism so that resorption is decreased and calcium increased. The growth hormone seems to add to bone mass and indirectly prevents resorption. The combination of growth hormone and calcitonin seems to cause an unusual amount of resorption. This research has shown that metallic endosteal blade implants are not automatically successful even in short spans with additional support from two abutment teeth. It is true that the type of occlusion of the squirrel monkey is different from that of man, but the prosthetic devices that were placed in these animals can be validly compared to similar devices placed in man. While the hygiene cannot be practiced effectively by the animal, the psychogenic and emotional problems of man offset this disadvantage. Also, the diet of the monkey is not as traumatic to a prosthesis as is man's. Two of the most important criteria for implant success have not proved satisfactory: (1) no pocket depth beyond 3 mm. and (2) negative radiographic pathosis around the implant. While this study was not meant to be one of criticism or evaluation of metallic implants, it should be noted that thyrocalcitonin and the growth hormone, individually used, played an important part in retarding bone resorption around the blade. Autogenous bone grafts for residual alveolar ridge restoration often fail due to rapid osseous resorption and volume loss. The maintenance of osseous elements in the autogenous bone grafts when calcitonin had been administered was quite revealing. This might be the chemotherapeutic basis for the many conditions involving bone that dentists are called upon to treat.

Stabilized record bases for complete dentures.

A step-by-step technique has been described to construct stabilized record bases which allows the dentist to take advantage of undercuts through the use of a resilient denture liner material in the undercut regions. The resilient denture liner material protects the rugae and prevents damage to the casts in the undercut regions during repeated placing and removal from the cast. Shellac denture base material at the posterior limit of the record base permits an easy method of checking the posterior palatal seal. The incorporation of the posterior palatal seal in the record base allows for adequate retention during the recording of the maxillomandibular jaw relation records and try-in procedures. The record bases made by the sprinkle-on technique are preferred to those made using the dough method. The bases are rigid, stable, not easily broken or warped, and fit accurately.

Physiologic determinants of primary impressions for complete dentures.

A technique has been described whereby a physiologic registration of the attached and unattached tissues of the denture-bearing areas can be attained. A low-fusing impression wax in conjunction with modeling compound is used for this purpose.

Complete denture secondary impression technique to minimize distortion of ridge and border tissues.

A technique has been described with which a physiologic and anatomic registration of the attached and unattached tissue of the denture-bearing areas can be attained. Clear acrylic resin trays aid in eliminating excessive displacement at the secondary impression phase. Inadequacies of the mucostatic concept include: Failure to register the tissues, which are important for retention and stability Certain metal bases that are part of this procedure can be implemented by only a small number of technicians Increased cost There are two shortcomings of the tissue-loading technique for complete denture impressions. Resulting retention and stability lasts only for a short period of time. Unwanted ridge resorption and tissue changes occur.

A loading impression technique for semiprecision and precision removable partial dentures.

The rationale of designing a seimprecision or precision distal-extension removable partial denture and the justification of ridge loading in distal-extension ridge impression techniques have been presented. The effectiveness of existing impression techniques in securing firm seats for abutment castings, accurate border extension of the denture base, and loading of the ridge mucosa has been evaluated. A technique has been described that overcomes the limitations of existing impression techniques for semiprecision and precision distal-extension removable partial dentures.