The effect of implant diameter, restoration design, and occlusal table variations on screw loosening of posterior single-tooth implant restorations.

The purpose of this study was to (1) determine in vitro the effect of narrowing the buccolingual width of the occlusal table on the untightening torque required to loosen gold prosthetic screws after subjecting implants and implant-supported restorations to occlusal loads, and (2) to compare the incidence of screw loosening and values of untightening torque of the screws among crowns supported by 1 wide-diameter as opposed to 2 standard implants after loading in vitro. The restorations were divided into 4 groups (group 1, a narrow crown supported by one 5-mm wide-diameter implant; group 2, a narrow crown supported by 2 standard 3.75-mm-diameter implants; group 3, a wide crown supported by one 5-mm wide-diameter implant; and group 4, a wide crown supported by 2 standard 3.75-mm-diameter implants). A custom-designed chewing machine was used to simulate the grinding phase of the masticatory cycle and lateral excursions. The crowns were subjected to a 6-kg load for 16660 cycles over 5.5 hours and were loaded at the outer and inner inclines and cusp tips with an untightening loading pattern. The untightening torque was measured for the gold screws in the different groups before and after loading at 4 different locations for 8 cycles on the simulated chewing machine. A 1-way analysis of variance indicated a significant difference (P < .001) among the test groups. Pairwise multiple comparison tests (Scheffe) were carried out on mean "change scores." Group 3 was significantly different from the other groups, which were not significantly different from each other. Restoring missing molars with 1 wide-diameter implant had a greater incidence of screw loosening as compared with 2 implants. Narrowing the occlusal table of the restoration is critical when using 1 implant to support a missing molar. The untightening torque of gold screws was not affected by changing the width of the occlusal table of crowns supported by 2 implants.

Congenital macroglossal angiodysplasia ("Lymphangioendotheliomatosis").

A case of congenital lingual angiodysplasia with macroglossia in a 5-year-old girl is presented. A diffusely enlarged tongue was present at birth and continued to grow as the child aged. It was accompanied by impaired speech, difficulty in eating and breathing, and sleep apnea, necessitating surgical intervention. The fundamental lesion represents a complex vascular malformation of the lymphangioma-hemangioma type, involving extensively the deep musculature of the tongue. Multifocal and multicentric cavernous lymphangioma-like and hemangioma-like areas merge with benign angioendotheliomatous-like foci in a background of variable muscle degeneration and marked fibrosis. Neither a borderline nor an overtly malignant vasoformative neoplasm was present. Because of its distinctively widespread, multicentric intramuscular distribution, this lesion may be construed as a diffuse variant of lingual lymphangioma-hemangioma malformation, closely resembling a previously described case of macroglossal lymphangioendotheliomatosis.

Depressed taste and smell in geriatric patients.

BACKGROUND: Geriatric patients have a number of dental care problems that younger patients do not encounter. The oral changes associated with aging can have a significant effect on the efficacy of dental treatment. TYPES OF STUDIES REVIEWED: The authors reviewed studies dealing with the causes of depressed sense of taste and smell; the causes included aging, disease, medications and dental problems. Based on their findings, the authors described the location and anatomy of taste buds and receptor cells for smell and explored appetite, saliva, food seasonings, nutrition and dietary recommendations. They also discussed the relationship of smoking and tongue cleaning to taste sensations. RESULTS: The authors found that considerable differences exist between elderly people and young people in regards to sensory perception and pleasantness of food flavors. Salt and bitter taste acuity declines with age, but sweet and sour perceptivity does not. Olfactory acuity also declines with age. The authors found that most of the studies reviewed suggested that the sense of smell is more impaired by aging compared with the sense of taste. Smoking diminishes the taste of food and makes flavorful foods taste flat, while tongue brushing can increase taste sensation for geriatric patients. CLINICAL IMPLICATIONS: Food can become tasteless and unappetizing for geriatric patients as the result of declining taste and smell perception. Geriatric patients should be encouraged to add seasonings to their food instead of relying on excessive consumption of salt and sugar to give their food flavor. Adequate nutrition, tongue cleaning and smoking cessation are recommended for geriatric dental patients.

Dental implants and the geriatric patient.

Dental care of the aging patient presents a number of problems not encountered in younger patients. Most of these problems result from tissue changes that occur during aging. Dental implants and implant-retained and/or implant-supported prostheses are viable treatment options for older patients. The majority of elderly patients in their younger retirement years are relatively healthy and not limited in activity. The clinician must be aware of the physical, metabolic, and endocrine changes associated with aging and how these changes may affect implant treatment. The elderly deserve the best care the dental profession can offer.