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Biomedical subjects

M Houpt

Publications and source records attributed to M Houpt.

At least 19 recordsLinked to original sources
PubMed1995

Mercury release from dental amalgams: an in vitro study under controlled chewing and brushing in an artificial mouth.

The release of mercury vapor from class I amalgam restorations prepared in human molar teeth was studied during chewing simulations in an artificial mouth of a bi-axial servo-hydraulic mechanical test system. So that the total mercury released from the restoration over a fixed time could be determined, a closed chamber surrounded the envelope of chewing motion. In addition, the influence of sampling frequency on mercury release was corrected by the use of different sampling frequencies over a fixed time interval of mercury release measurement and extrapolation to zero sampling time. Thus, a combination of a closed environment and an extrapolation method to determine the mercury release under continuous sampling was used to determine the mercury released under normal breathing conditions. The measured mercury release rate data were used to calculate the potential daily mercury dose in a patient due to a single amalgam restoration, following the method previously outlined by Berglund. The mercury release from both a conventional and a high-copper amalgam was evaluated at different age intervals after the restoration was placed in the teeth. The results show that while the age of the amalgam and the amalgam type influence the extent of mercury release during the initial non-steady-state conditions, the steady-state value of mercury daily dose due to a single amalgam filling is 0.03 micrograms/day, which is well below the calculated threshold-limiting value (TLV) of 82.29 micrograms/day considered dangerous for occupational exposure in the United States.

Air Pollution, Indoor↗
PubMed1995

Hypohidrotic ectodermal dysplasia: characteristics and treatment.

Hypohidrotic ectodermal dysplasia is a rare congenital disease that affects several ectodermal structures. The disease is usually transmitted as an X-linked recessive trait in which the gene is carried by the female and manifested in the male. Manifestations of the disease differ in severity and may involve teeth, skin, hair, nails, and sweat and sebaceous glands. Most affected children require extensive dental treatment to restore their appearance and help the development of a positive self-image.

Adolescent↗
PubMed1995

The effect of age on the behavioral responses of mice following diazepam and midazolam sedation in combination with nitrous oxide.

This study examined the effects of age on the behavior of mice administered one of two benzodiazepines with and without nitrous oxide. Young (3 wk +/- 3 days) and adolescent (7 wk +/- 3 days) male DBA-2 mice were administered oral diazepam (2.0 or 3.5 mg/kg), midazolam (0.75 or 1.2 mg/kg), or a placebo in combination with 50% nitrous oxide/50% oxygen, or room air. The mouse staircase model was used, where the number of rears (NR) served as an index of anxiety, and the number of steps ascended (NSA) as an index of sedation. No significant differences in the responses between the ages were noted. Nitrous oxide seemed to increase the NR and NSA, whereas the benzodiazepines alone did not affect behavior. These DBA-2 mice may represent a strain that is less sensitive to the anxiolytic-sedative effects of the benzodiazepines than are other strains.

Age Factors↗
PubMed1994

The preventive resin (composite resin/sealant) restoration: nine-year results.

This study was performed to examine the 9-year success of the composite resin/sealant restoration, which uses "sealing for prevention" of fissure caries rather than "cavity extension for prevention." Three hundred thirty-two Class I restorations were placed in the occlusal surfaces of 240 permanent molar teeth in 114 children aged 6 to 14. Cavity preparations were made in occlusal surfaces, and caries was removed with no attempt to create any additional retention or remove undermined enamel. Exposed dentin was covered with Dycal and the cavity was restored with Radiopaque Adaptic, which was then covered with Delton fissure sealant. Incipient lesions confined to the enamel were restored only with Delton. After 9 years, 79 restorations in 28 subjects were examined for sealant retention, marginal staining, and the presence of dental caries. Forty-three restorations (54%) had completely retained sealants, 20 (25%) had sustained partial loss, and 16 (20%) of the restorations had lost all sealant. Dental caries occurred in 19 (25%) of the restorations that had sealant loss. An additional 16 teeth had proximal caries unrelated to the occlusal restoration. These findings demonstrated that the composite resin/sealant (preventive resin) restoration produced excellent long-term results.

Adolescent↗
PubMed1989

An epidemiologic study of the oral health status of high school students in New Jersey.

This study was performed in order to record the prevalence of tooth decay in high school students in New Jersey. During the Spring of 1986, 3,556 students, aged 13 to 18 years, in 8 public high schools in 7 communities, participated in the study. The subjects were examined by 3 trained examiners with mirror, explorer, air syringe and overhead auxiliary light. A lesion was recorded as dental caries if there was a perceptible break in the enamel surface. Questionable incipient areas were not recorded as carious lesions. Mean DMFT was found to be 4.17 +/- 3.7 and mean DMFS was 7.02 +/- 7.4. Hispanic subjects had more decay (DMFT 4.98, DMFS 9.03) than black subjects (DMFT 4.13, DMFS 6.94) and white subjects (DMFT 3.53, DMFS 5.43). Females had more decay (DMFT 4.51, DMFS 7.67) than males (DMFT 3.79, DMFS 6.33). Hispanic and black subjects also had more untreated decay (24 and 22 percent decayed of the DMFT) compared with only 11% untreated decay in white subjects. Socioeconomic level was inversely related to caries activity; however, geographic location of the school within the state (north versus south) was not a factor.

Adolescent↗
PubMed1989

Effects of chloral hydrate on nitrous oxide sedation of children.

This study was conducted to examine the effects of chloral hydrate on nitrous oxide sedation of young children for dental treatment. Nineteen children, ranging in age from 19 to 41 months (mean 30 months), participated in this double-blind study. The subjects were assigned randomly to receive either a placebo or chloral hydrate (50 mg/kg) for the first visit with the alternate regimen administered during the second appointment. In addition, all subjects received inhalation nitrous oxide/oxygen at a concentration of 50%, and were restrained in a Papoose board (Olympic Medical Group; Seattle, WA) with head restraint. Seventy-four per cent of sedations were classified as very good or excellent when chloral hydrate was administered with nitrous oxide compared with only 26% when the placebo was administered.

Anesthesia, Dental↗
PubMed1987

Autopolymerized versus light-polymerized fissure sealant.

This study found that 31 months after placement of a sealant, no significant difference was seen in the clinical performance and retention between the visible light-polymerized and autopolymerized materials. Practitioners can use either material without compromising efficacy.

Chemical Phenomena↗
PubMed1985

Occlusal composite restorations: 4-year results.

A study was performed to determine the success of a conservative cavity preparation using the principle of sealing for prevention rather than cavity extension for prevention. A total of 332 restorations were placed in 240 teeth of 110 subjects, aged 6 to 14, with a mean age of 8 years. After 4 years, 205 restorations were examined. Caries appeared in 13 teeth and sealant wear occurred in 14 restorations. Complete sealant loss was observed in eight restorations and partial loss in 38, leaving 156 restorations with complete retention of the sealant. These preliminary results show that conservative cavity preparation with sealing for prevention is a successful technique that conserves valuable tooth structure.

Adolescent↗