Feulgen microspectrophotometry of oral cancer and leukoplakia.

Feulgen microspectrophotometry was performed using the two wavelength method on 33 lesions and showed that five of ten carcinomas and 12 of 16 leukoplakias had diploid cell lines. This correlates well with similar findings in cervical cancer and dysplasia suggesting that changes in nuclear deoxyribonucleic acid content occur quite early in the evolution of cancer.

The effect of intrasulcular brushing on sulcular epithelial permeability.

The purpose of the present study was to determine the effect of intrasulcular toothbrushing on permeability of the sulcular epithelium. Twenty-four dental students were divided into two groups of 12 each. On day 0, subjects in Group I began having the buccal aspects of the maxillary right first and second molars brushed for 30 seconds daily for 49 days by an examiner using an intrasulcular technique while subjects in Group II had the same teeth brushed with an extrasulcular technique. On day 49, clinical evaluation of inflammation was performed and biopsies were taken to evaluate gingival inflammation, sulcular epithelial keratinization and permeability of the sulcular epithelium in vitro using a microperfusion technique. Results indicate that subjects in both groups had attained equally high levels of gingival health. The intrasulcular group demonstrated a significantly higher degree of sulcular epithelial keratinization. However, no relationship was found between the degree of sulcular epithelial keratinization and sulcular epithelial permeability. Thus, the benefits derived from intrasulcular brushing and increasing sulcular epithelial keratinization are questionable.

Influences of directed research and clinical observations on the development of a tartar control whitening dentifrice.

Early literature described the benefits of cleaning the mouth and teeth to prevent tartar accumulation and tooth loss. For more than a century, the need for meticulous tooth scaling and regular brushing to maintain oral health has been recorded. More recently, because of innovative research into the chemical and biological activity of saliva, dentifrices have been formulated which specifically interrupt the mineralization of plaque and food debris to stain and calculus. Proof of efficacy of these dentifrices are obtained with well-designed clinical tests which quantify stain and calculus by using reliable scoring systems.

A retrospective of normal oral healthcare procedures vs. power brush/jet lavage with a corroborative study.

The efficacy of power brushes and/or oral irrigating devices in comparison to manual brushing has been the subject of study and controversial results for some thirty years. Recently, a well-designed study has reported that carefully taught, consistently reinforced and monitored toothbrushing combined with necessary professional intervention is as effective as power brushing with and without oral lavage. Because the usual individual in the work-a-day world cannot or will not indulge regularly in these elaborate procedures, a simple, small sample test of comparative efficacy was done and submitted to a paired analysis. Results demonstrated that not only are these power devices as good as demonstrated by the reported studies, but also are superior for the type of patient most often encountered in daily practice--the person who does not or who cannot comply completely with instructions and who cannot constantly be monitored for compliance.

The effect of chronic parathyroid extract on tooth eruption and dental tissues in osteopetrotic mice.

The grey lethal mouse is an osteopetrotic mutant in which there is diffuse sclerosis of the entire skeleton and the teeth remain trapped in the jaws. The condition was treated with daily subcutaneous injections of PTE beginning at birth. PTE induced molar tooth eruption in some mutants and improved root formation (without eruption) in others. However, the zone of predentine in the crown of the tooth remained abnormally wide and dentinogenesis remained irregular. Resorption of alveolar bone was adequate to permit complete tooth eruption in some animals and increased root formation in others.