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Biomedical subjects

J C Meiers

Publications and source records attributed to J C Meiers.

At least 37 records · Page 2Linked to original sources
PubMed1995

Dentin surface treatments and glass ionomer microleakage.

PURPOSE: To investigate the effect of various dentin treatments on the microleakage of Class V restorations restored with a resin-modified glass ionomer restorative cement. MATERIALS AND METHODS: Forty extracted noncarious molar teeth received Class V preparations with the occlusal margin in enamel and the gingival margin in dentin. Preparations were restored with Fuji II LC glass ionomer restorative material. Five dentin treatments were tested prior to restoration (n = 16): Group 1: without dentin pretreatment; Group 2: with GC Dentin Conditioner (10% polyacrylic acid solution); Group 3: with ProBond Dentin Primer; Group 4: with GC Dentin Conditioner and ProBond Dentin Primer; Group 5: with ProBond Dentin Primer followed by application of ProBond adhesive. Samples were thermocycled, stained with 0.5% basic fuchsin, and sectioned to evaluate microleakage. Data was analyzed using Kruskal-Wallis and Wilcoxon Signed-Rank Tests at a significance level of P < 0.05. SEM analysis was performed on selected samples to examine the dentin/glass ionomer interface. RESULTS: There was no statistically significant difference between any of the dentin pretreatments with regard to enamel or dentin microleakage. SEM analysis indicated excellent adaptation between glass ionomer and dentin for all treatment groups.

Acid Etching, Dental↗
PubMed1995

Microleakage of dentin-amalgam bonding agents.

PURPOSE: To evaluate in vitro the microleakage of various dentin bond/resin liner systems when used with both a spherical and an admixture alloy. MATERIALS AND METHODS: Class V cavity preparations were prepared on 60 noncarious extracted human molar teeth with one margin in enamel and another in dentin and restored with either Dispersalloy or Tytin alloy. Treatment groups utilizing either no liner, Copalite varnish, Amalgambond Plus/HPA, Tenure with Panavia EX Dental Adhesive, Syntac with Dual Cem, and All-Bond 2 with Liner F were tested. Samples were thermocycled, stained, and sectioned to evaluate microleakage. RESULTS: A significant reduction in microleakage at the enamel and dentin margins was found in all dentin bond system/resin liner groups when compared to unlined and Copalite-lined alloys. There were no significant differences in total microleakage scores between the alloy types. Statistically significant differences in microleakage were detected between some systems. The Tenure with Panavia EX treatment group exhibited a significantly lower total microleakage when used with Tytin. The Syntac/Dual Cem treatment groups exhibited a significantly higher total microleakage when used with Dispersalloy.

Analysis of Variance↗
PubMed1984

The effect of an antibacterial solution on the microflora of human incipient fissure caries.

A technique for collecting various levels of plaque from incipient occlusal fissure caries was used to evaluate the antibacterial properties of a solution containing I2-KI, CuSO4, and ethanol. In comparison with control fissures (n = 6), the treated fissures (n = 9) showed a 98% difference in recoverable bacteria, with the killing of S. mutans, Actinomyces, and lactobacilli appearing to reflect the level of agent penetration.

Actinomyces↗
PubMed1984

Fissure removal and needle scraping for evaluation of the bacteria in occlusal fissures of human teeth.

The bacterial counts obtained with a needle-scrape method for collecting plaque samples from human occlusal fissures with incipient caries were compared with the microflora remaining in the fissures as determined with a fissure removal method. Scraping of six fissures with a sterile needle recovered only 18.2% of the total recovered fissure flora. The needle-scrape method failed to detect specific cariogenic bacteria which were present in four of the fissures. Treatment of nine fissures with an antibacterial solution demonstrated that the needle method failed to detect viable bacteria in eight of the fissures which were subsequently shown to contain bacteria by fissure removal. The commonly used needle-scraping method does not appear adequate for studies on the effect of antimicrobial agents on fissure plaque.

Adolescent↗
PubMed1982

A microbiological analysis of human early carious and non-carious fissures.

The fissure sampling technique consisted of removing the fissure using a bur in a high-speed handpiece with water spray and then suctioning the fissural contents and the water spray into a sterile sampling container. Sixty-eight teeth were sampled. Total bacterial counts, total streptococcal counts, and counts of Streptococcus mutans, Streptococcus sanguis, Streptococcus faecalis, Actinomyces viscosus, and lactobacilli were performed on the fissural samples. There was a four-fold increase in the total number of microorganisms recovered from carious (N = 48) compared to non-carious (N = 20) fissures. S. mutans was the only microorganism common to all carious fissures.

Actinomyces↗
PubMedDate not supplied

Microleakage of Compoglass-F and Dyract-AP compomers in Class V preparations after salivary contamination.

PURPOSE: The purpose of this study was to investigate the effect of salivary contamination on the microleakage within Class V preparations of teeth restored with either Compoglass-F/Syntac SC and Dyract-AP/Prime and Bond 2.1. METHODS: Class V cavity preparations with occlusal margins in enamel and gingival margins in cementum were prepared on the buccal and lingual surfaces of extracted human permanent molar teeth. Preparations were distributed randomly into 4 treatment groups (N = 16) consisting of the two compomers and their respective bonding agents with and without salivary contamination. After treatment, the samples were stored in tap water for 24 hours, thermocycled, stained with dye, sectioned, and scored for microleakage. RESULTS: Salivary contamination had no significant effect on enamel microleakage but significantly increased both linear and penetrating microleakage versus non-contaminated for both compomer/dentin bonding systems. CONCLUSION: These data indicate salivary contamination adversely effects gingival but not enamel microleakage when Class V restorations are restored with either Compoglass F/Syntac SC or Dyract-AP/Prime and Bond 2.1.

Analysis of Variance↗
PubMedDate not supplied

Rx for caries prevention: time line for home care. A software aid for communication of patient instructions for management of dental caries.

Treatment of a caries active patient requires the clinician to be knowledgeable in the restorative and risk management issues with which these patients often present. Modifications of risk factors that promote dental caries play an important part in the long-term restorative success in these patients. Patient compliance to recommendations addressing modifiable caries risk factors for maintenance of oral health is important to long-term caries risk management. Effective dentist-patient or hygienist-patient communication is a first step to encouraging a proactive role by the patient. Others have reported verbal communication accompanied by written communication to result in better compliance compared to verbal communication, alone (Tagliacozzo & Ima, 1970; MacDonald, MacDonald & Phoenix, 1977; Baker & others, 1991; Harvey & Plumridge, 1991; Vukmir & others, 1993; Makoul, Arntson & Schofield, 1995). Further evidence shows that medical patients who misunderstand their treatment plans and associated instructions usually exhibit poor compliance to following directions (Cargil, 1992; Counsell, Geddis & Smith, 1993; Vukmir & others, 1993; Makoul & others, 1995; Mayeaux & others, 1996). Computer-generated (printed) instructions were shown to significantly increase compliance to emergency room instructions when compared to verbal or verbal + hand-written instructions (Vukmir & others, 1993). Written instructions for use in management of dental caries have not been widely addressed in the literature (Fuller & Harding, 1991; Benn & others, 1997). This report presents a novel computer-generated, graphic approach to written communication that recognizes the patient's need to be reminded that home care consists of daily cyclic events. The objective of this approach is to promote communication with and comprehension by a wider population range than what might be affected by text-only instructions. The software for this method is pre-loaded with recommendations that can be modified by the dentist or hygienist and can be easily adapted as part of a comprehensive disease management program used in the office.

Communication↗
PubMedDate not supplied

Direct measurement of dimensional accuracy with three denture-processing techniques.

The Michigan Computer-Graphics Coordinate Measurement System (MCGCMS) was used to determine the dimensional accuracy of dentures processed by three different techniques: conventional heat compression, microwave, and visible-light activation. Standardized dentures were fabricated from casts made in an RTV silicone mold. All casts were duplicated with hydrocolloid and 42 dentures were made (ie, 14 dentures for each technique). The MCGCMS measured 22 points on two frontal planes to compare master casts to dentures. The results showed no significant difference in overall dimensional accuracy. At specific sites, however, the visible-light-activated technique produced significantly more flange distortion than did either the conventional or microwave techniques.

Acrylic Resins↗
PubMedDate not supplied

Early erosion of glass-ionomer cement at crown margins.

This study investigated the early erosion of glass ionomer-cement that had been used to lute complete cast crowns. Restorations had margins ending on either enamel or cementum and had various sizes of marginal openings. These restorations were compared to those using a standard zinc phosphate cement. Results showed that leaving the band of excess cement, expressed during the seating of the crown, undisturbed for 10 minutes prevented significant erosion in a wet field. A resin coat was not necessary to provide further protection after removal of the band. Zinc phosphate cement also showed significant early erosion when exposed to moisture.

Cementation↗
PubMedDate not supplied

Microleakage of a dental amalgam alloy bonding agent.

Amalgambond (a 4-META derivative resin bond agent) was evaluated for its effectiveness in reducing microleakage compared to copal varnish and no lining agent in class 5 amalgam preparations restored with either an admix alloy (Dispersalloy) or a spherical alloy (Tytin). Teeth were thermocycled between 5 and 55 degrees C with two 4-META/amalgam groups additionally aged in 37 degrees C water for 30 days prior to thermocycling. Nonaged, 4-META/amalgam restorations showed significantly less microleakage (P < 0.05) at enamel and dentin margins compared to copal varnish or nonlined restorations. Within the 4-META groups, the 4-META/Dispersalloy restorations had significantly less microleakage than the 4-META/Tytin restorations at enamel margins. Microleakage in the aged 4-META/amalgam restorations was significantly greater at both the enamel and dentin margins than in the analogous nonaged groups. SEM evaluation of the 4-META lined restorations found internal cavity surfaces of the preparations to be sealed by the resin liner with separations and apparent microleakage occurring at the 4-META/amalgam interface.

Analysis of Variance↗
PubMedDate not supplied

Repair of an aged, contaminated indirect composite resin with a direct, visible-light-cured composite resin.

This study investigated the interfacial shear bond strength of a contaminated, aged, heat- and pressure-processed, indirect composite resin (Concept) repaired with a direct, visible-light-cured composite resin (Heliomolar). Concept samples were aged by thermocycling and contaminated in tobacco juice. The bonding surfaces were prepared by sanding with 500-grit sandpaper or air abrading with 50-micron aluminum oxide. Prepared Concept surfaces received one or more of the following intermediary resin treatments before the addition of Heliomolar: Heliobond, Special Bond 2, All-Bond system, All-Bond bonding agent, or no bonding agent, and they were immediately thermocycled. Air abrasion produced significantly higher bond strengths than sanding for all intermediary resin surface treatments. The All-Bond-treated Concept surfaces showed the highest interfacial bond strengths within the air abraded and sanded groups. Visual and SEM examination of fractured repair surfaces indicated adhesive failure within all treatment groups.

Acrylates↗
PubMedDate not supplied

Shear bond strength of resin composite to Dicor treated with 4-META.

The combination of Etch-Free Primer and C&B Metabond has been reported to produce high resin composite to feldspathic porcelain bond strengths without hydrofluoric acid etching. This study compared the shear bond strength of resin composite to a castable glass ceramic that was treated with either Etch-Free Primer and C&B Metabond or ammonium bifluoride (NH5F2) etch/silane under various surface treatment and thermal stress variables. Bond strengths after Etch-Free Primer/C&B Metabond treatment were significantly lower than those for NH5F2/silane treatment. Thermocycling was the most important variable in reducing Etch-Free Primer/C&B Metabond bond strengths.

Acrylic Resins↗
PubMedDate not supplied

Fracture resistance of premolars with MOD amalgam restorations lined with Amalgambond.

A comparison was made of the fracture resistance of premolar teeth with mesial-occlusal-distal (MOD) amalgam preparations lined with either a resin containing 4-META (Amalgambond) or copal varnish (Plastodent) and restored with a spherical alloy (Tytin). Restored teeth were aged for 7 or 67 days at 37 degrees C in 100% humidity and thermocycled between 5 and 55 degrees C for 3500 cycles. There was no significant difference in the mean fracture resistance between teeth lined with Amalgambond and teeth lined with Plastodent under any of the test conditions. SEM analysis of thermocycled specimens showed no evidence of maintained adhesion between the Amalgambond and amalgam.

Analysis of Variance↗
PubMedDate not supplied

Direct esthetic restoration of anterior root canal-treated teeth.

The esthetic restoration of anterior root canal-treated teeth with significant loss of tooth structure is a challenging clinical situation. For younger patients or for patients requiring interim treatment plans, restoring badly broken-down anterior teeth with composite resin provides an expedient and esthetic solution. Current visible-light-activated composite resin materials require an incremental build-up to ensure adequate depth of cure. With the use of custom-contoured, stabilized, thin crown forms and strategically placed vent holes, the clinician can efficiently provide cost-effective direct composite resin restorations that meet the patients' esthetic needs.

Composite Resins↗