A clinical investigation of the efficacy of a tooth-whitening gel.

The objective of this randomized, controlled, examiner-blind, parallel-group clinical study was to determine whether a tooth-whitening gel (Colgate Simply White Night Clear Whitening Gel) can significantly lighten teeth when used once daily at night, as compared with a commercially available dentifrice. Following a baseline tooth shade evaluation using the VITA Shade Guide, qualifying adult male and female subjects from the Buffalo, New York area were randomized into 2 treatment groups, which were balanced for baseline VITA Shade Guide scores, gender, and age. The treatment groups were: (1) a commercially available dentifrice only; and (2) a tooth-whitening gel in addition to a commercially available dentifrice.

An investigation into the effect of three months' clinical wear on toothbrush efficacy: results from two independent studies.

Objective: Limited evidence has suggested that a worn toothbrush may be significantly less effective than a new brush with respect to plaque removal. Two independent studies, one with a manual toothbrush and one with a powered toothbrush, were undertaken to compared the ability of these toothbrushes as new and after three months' use to remove plaque.

Methodology: Subjects from a general population were given either an Oral-B CrossAction manual toothbrush (Study 1) or a Braun Oral-B Battery (D4) toothbrush (Study 2).

A single-use and 3-month clinical investigation of the comparative efficacy of a battery-operated power toothbrush and a manual toothbrush.

Purpose: To compare the safety and efficacy of a manual toothbrush and a battery-operated power toothbrush in two separate studies, one utilizing a single-use design and the other a 3-month parallel-group design.

Materials And Methods: The toothbrushes compared in the two studies were the Oral-B CrossAction manual toothbrush and the Colgate Actibrush battery-operated power toothbrush. The single-use study, which used a single-blind, cross-over design, involved 71 healthy subjects, who were instructed to abstain from oral hygiene for 23-25 hours prior to brushing with each of the two toothbrushes.

Efficacy of baking soda-containing chewing gum in removing natural tooth stain.

A 14-week, double-blind, randomized clinical trial was conducted with 126 healthy volunteers to compare the efficacy of twice-daily use of 3 baking soda-containing chewing gums in removing natural tooth stain when used in conjunction with a program of regular oral hygiene. All 3 chewing gums significantly reduced extrinsic stain (P < .0001) and improved the whitened appearance of teeth (P < .

Clinical study to compare extrinsic stain formation in subjects using three dentifrice formulations.

The purpose of this study was to compare the degree of extrinsic dental stain formed with the use of three dentifrices: (1) a new dentifrice formulation containing 5.0% potassium nitrate and 0.454% stannous fluoride in a silica base (Colgate Sensitive Maximum Strength Toothpaste, Colgate-Palmolive Co.

Comparative investigation of the desensitizing efficacy of a new dentifrice: a 14-day clinical study.

The effect on dentinal hypersensitivity from the use of a new formulation dentifrice containing 5.0% potassium nitrate and 0.454% stannous fluoride in a silica base (Colgate Sensitive Maximum Strength Toothpaste, Colgate-Palmolive Co.

Anticalculus effect of two zinc citrate/essential oil-containing dentifrices.

Purpose: To assess the feasibility of incorporating zinc citrate, a known anticalculus ingredient, into a dentifrice formulation containing a fixed combination of essential oils, a known antiplaque/antigingivitis agent.

Materials And Methods: This randomized, parallel, double-blind study evaluated the potential of two essential oil dentifrice formulations containing different levels of zinc citrate (1.0% and 2.

A comparative 3-month clinical investigation of the safety and efficacy of a battery-operated and a rechargeable oscillating-rotating power toothbrush.

Purpose: To compare the safety and efficacy of two oscillating-rotating power toothbrushes, the rechargeable Braun Oral-B D8 and the battery-powered Colgate Actibrush.

Materials And Methods: This was a randomized, examiner-blind, parallel-group study, carried out over 3 months of product use, involving a total of 113 healthy subjects with a plaque score of > or = 1.5 and a gingivitis score of > or = 1.

A clinical comparison of two calculus-inhibiting dentifrices.

The objective of this double-blind clinical study, conducted in harmony with the Volpe-Manhold design for studies of dental calculus, was to compare the effect on supragingival calculus formation of a dentifrice containing pyrophosphate, tripolyphosphate and a copolymer in a 0.243% sodium fluoride/silica base (Test Dentifrice), to that of a commercially available calculus-inhibiting dentifrice containing tetrapotassium pyrophosphate, disodium pyrophosphate and tetrasodium pyrophosphate in a 0.243% sodium fluoride/silica base (Positive Control Dentifrice).

Anticalculus efficacy of an antiseptic mouthrinse containing zinc chloride.

Background: The authors undertook a controlled clinical study to determine the efficacy of a tartar-control antiseptic mouthrinse in inhibiting the development of supragingival dental calculus.

Methods: After undergoing a dental prophylaxis, 334 subjects with a moderate rate of calculus formation were stratified and randomly assigned to one of three groups: positive control (using a tartar-control toothpaste and an antiseptic rinse), negative control (using a regular toothpaste and an antiseptic mouthrinse) or experimental (using a regular dentifrice and a tartar-control mouthrinse). Subjects brushed and rinsed twice daily, unsupervised, for four months.

Immunogenic and protective response in mice immunized with a purified, inactivated, Dengue-2 virus vaccine prototype made in fetal rhesus lung cells.

The feasibility of a purified, inactivated vaccine (PIV) against dengue type 2 (DEN-2) virus was explored. Dengue-2 virus strain 16681 was used for producing a monotypic PIV. Virus adapted to fetal rhesus lung (FRhL-2) cells was harvested from roller bottle culture supernatant fluids, concentrated, and purified on sucrose gradients.

The role of limbic structures in the modulation of ACTH responses following adrenalectomy.

The role of the HIPP, DF, and the lateral SPT as well as of the central AMG nucleus in ACTH hypersecretion following Adex, was studied in male rats. In animals with bilateral dorsal hippocampectomy, DF section, or SPT lesions there was a much greater increase in ACTH hypersecretion when compared to Adex alone. Implants of CS in the paraventricular nucleus of the hypothalamus prevented the rise in serum ACTH following Adex, and this effect was reversed by hippocampectomy.

Effects of HSV-1, a neurotropic virus, on the hypothalamic-pituitary-adrenocortical axis in rats.

It is well established that the hypothalamic-pituitary-adrenocortical (HPA) axis is activated during systemic viral diseases. In this study we examined the effects of a neurotropic virus, herpes simplex virus type 1 (HSV-1), on the HPA axis in male rats. Following corneal inoculation with HSV-1, the virus invaded the nervous system and replicated in the brainstem without clinical signs of disease.

Limbic pathways and hypothalamic neurotransmitters mediating adrenocortical responses to neural stimuli.

One of the major phenomena related to the stress response is the activation of the hypothalamo-pituitary-adrenocortical (HPA) axis. This axis consists of corticotropin releasing factor-41 in the paraventricular nucleus of the hypothalamus (PVN), which in response to a variety of stimuli is released into the portal circulation and stimulates pituitary ACTH secretion and subsequently adrenocortical discharge. The mechanisms involved in the activation are not uniform and the responses to various stimuli are mediated by different neural pathways.

Differential effect of amygdaloid lesions on CRF-41, ACTH and corticosterone responses following neural stimuli.

The effect of amygdaloid (AMG) lesions on changes in median eminence (ME) CRF-41 and serum ACTH and corticosterone (CS) levels following neural stimuli were investigated in rats. In intact animals photic or acoustic stimuli caused CRF-41 depletion from the ME and a rise in serum ACTH and CS levels. In rats with medial or central AMG nuclei lesions, these responses were blocked.

Clinical effect of a triclosan-containing dentifrice on plaque and gingivitis: a six-month study.

A total of 294 adult male and female subjects completed a 6-month, double-blind clinical trial designed to evaluate the effects of a dentifrice which contained 0.3% triclosan in conjunction with 2% of a methoxyethylene/maleic acid copolymer in a 0.243% sodium fluoride/silica base, relative to a control dentifrice, on supragingival plaque accumulation and gingivitis.

Differential recovery of adrenocortical responses to neural stimuli following administration of 5,7-dihydroxytryptamine into the hypothalamus.

In view of the role of serotonin in adrenocortical regulation, the effects of depletion of hypothalamic serotonin, using localized injections of the neurotoxin 5,7-dihydroxytryptamine into the hypothalamic paraventricular nucleus, on the rise in plasma corticosterone following afferent neural stimulation, were studied. The neurotoxin caused a significant reduction (p less than 0.001) in hypothalamic serotonin content of about 50% during the first month and about 30% up to two months later.

Adrenal responses and neurotransmitters in posterior hypothalamic deafferentation.

The effects of a small posterior hypothalamic deafferentation (PHD) on adrenocortical responses to peripheral neural stimuli were investigated in rats. PHD inhibited the rise in plasma corticosterone (CS) following photic and acoustic stimulation, but did not affect the adrenocortical response following sciatic nerve stimulation. PHD did not change the content of norepinephrine in the paraventricular nucleus of the hypothalamus, however, it reduced the serotonin content by about 30%.

The preoptic area and bed nucleus of the stria terminalis are involved in the effects of the amygdala on adrenocortical secretion.

In view of the role of the amygdala in the modulation of adrenocortical secretion we have studied the neural pathways which mediate this response. Changes in plasma corticosterone following medial amygdala stimulation, under pentobarbital anaesthesia, were studied in rats which chronically implanted electrodes in intact and lesioned animals. The rise in plasma corticosterone following amygdala stimulation was inhibited by bilateral lesions of the stria terminals, medial preoptic area, and bed nucleus of the stria terminalis, and to a greater extent by a combined lesion of the latter two structures.

Effect of interleukin-1 on adrenocortical activity in intact and hypothalamic deafferentated male rats.

The present study was designed to elucidate the site of action of interleukin 1 (IL-1) modulation of the hypothalamic-hypophyseal-adrenal (HHA) axis. An intraperitoneal injection of recombinant human IL-1 beta (160 U/rat) significantly elevated serum levels of ACTH and corticosterone (CS). In rats with complete mediobasal hypothalamic deafferentation, the HHA response to IL-1 was inhibited.

Hypothalamic norepinephrine mediates limbic effects on adrenocortical secretion.

The purpose of this study was to elucidate the role of norepinephrine (NE) in the mediation of adrenocortical responses following limbic stimuli. The effects of stimulation of the dorsal and ventral hippocampus and the midbrain reticular formation on the plasma corticosterone (CS) levels was studied in rats with vehicle or 6-hydroxydopamine (6-OHDA) injected bilaterally into the paraventricular nucleus of the hypothalamus (PVN). The injection of 6-OHDA caused a very significant reduction in the concentration of PVN NE and blocked the rise in plasma CS following the stimulation of the above three limbic structures.

Differential adrenocortical responses to neural stimuli following intracerebroventricular injection of nicotinic acetylcholine receptor antibodies in rats.

The aim of the present study was to investigate the involvement of central nervous system nicotinic receptors for acetylcholine in the adrenocortical responses to neural stimuli. Adult male rats received a daily intraventricular injection of partially purified nicotinic acetylcholine receptor antibodies (anti-AchR), obtained from a patient with myasthenia gravis, for 5 consecutive days. Control animals were treated similarly with immunoglobulins obtained from normal human serum.

Involvement of ventral noradrenergic bundle in corticosterone secretion following neural stimuli.

In view of the involvement of noradrenaline (NA) in the regulation of adrenocortical secretion, its role in the rise of plasma corticosterone following neural stimuli was evaluated in rats. The injection of the catecholamine neurotoxin 6-hydroxydopamine (6-OHDA) into the ventral noradrenergic bundle in the brain stem, which projects to the hypothalamus, caused an average depletion of NA of 72% and 78% in the mediobasal hypothalamus and the paraventricular nuclei respectively, when compared to the rats injected with vehicle. In the animals injected with 6-OHDA, the basal level of corticosterone in plasma and the response to stress induced with ether were not affected.

Hypothalamic afferent connections mediating adrenocortical responses that follow hippocampal stimulation.

This study identified some neural pathways which mediate the adrenocortical responses that follow hippocampal stimulation. The increase in plasma corticosterone following dorsal hippocampus stimulation, in rats with electrodes chronically implanted under pentobarbital anesthesia, was blocked by dorsal fornix and lateral septal lesions and by small posterior hypothalamic deafferentation. Fimbria transection, lateral septal lesions, and posterior hypothalamic deafferentation, but not midbrain reticular formation lesions, also blocked the adrenocortical responses to ventral hippocampus stimulation.