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G Z Wright

Publications and source records attributed to G Z Wright.

43 records · Page 3Linked to original sources
PubMedDate not supplied

Direct bonding applied to space maintenance.

Based on the conditions of this study, the following conclusions were reached: A success rate of 70 percent seems to justify further investigation into direct bonded space maintainers. A space maintainer directly bonded to the buccal surfaces seems to be efficient in maintaining single tooth spaces. Primary-to-primary appliances were more successful than the primary-to-permanent appliances, which suggests that incomplete first permanent molar eruption and a posterior location affect appliance durability.

Acid Etching, Dental↗
PubMedDate not supplied

Management of lower incisor crowding in the early mixed dentition.

This paper describes normal and problem development in lower incisor positioning and offers options for management of crowded cases. The following guidelines were recommended, (1) lower incisor crowding of 2 mm or less and with an intercanine width greater than 28mm will usually resolve spontaneously, (2) lower incisor crowding of 3-4 mm is best managed by discing of the primary dentition, (3) crowding assessment of 5-9 mm requires extraction of primary teeth with probable placement of a supportive lingual arch and, (4) crowding greater than 10 mm requires fixed appliance therapy and careful orthodontic management with attention to the severity of the malocclusion.

Cephalometry↗
PubMedDate not supplied

The effect of internal bevel on marginal leakage at the approximal surface of Class 2 composite restorations.

The aim of this study was to assess the effect of intentionally leaving undermined enamel (internal bevel) along the cervical margins of class 2 composites on marginal leakage. Conventional MO and DO cavity preparations were prepared in 25 extracted permanent premolars. In each tooth the cervical margin was a butt-joint for the control group and an internal bevel for the experimental group. A transparent celluloid matrix was adapted and the teeth were restored with scotchbond Multi-Purpose and increments of Z100. A U-shaped increment was attached to the buccal and lingual walls and cervical floor of the box, leaving a gap for a middle increment. A third increment filled the occlusal part of the cavity. Following thermocycling the teeth were immersed in basic fuchsin for 24 hours, and 0.5 mm-wide sections were cut in a mesiodistal direction. Dye penetration was scored: 0 = no penetration; 1 = dye along enamel tooth interface; 2 = dye along the gingival floor; 3 = dye along pulpal wall; 4 = dye penetration into dentinal tubules. The experimental group showed 17 teeth (68%) with no dye penetration, compared to eight (32%) in the control group. Severe dye penetration (score 4) was found in only four teeth (16%) of the experimental group and 12 (48%) of the controls. The difference between the groups was statistically significant (Wilcoxon matched-pairs signed-rank test; P < 0.01). This study showed that an internal bevel at the cervical margins of class 2 composite restorations reduces marginal leakage when compared to a conventional butt-joint cavity preparation.

Composite Resins↗
PubMedDate not supplied

Microleakage of sealants after conventional, bur, and air-abrasion preparation of pits and fissures.

PURPOSE: The aim of this study was to compare the microleakage of unfilled and filled sealants after conventional, bur, and air-abrasion tooth preparation. METHODS: Seventy-two extracted molars were randomly divided into three groups. In group 1, 24 teeth were prepared by pumicing and acid etching with 37% phosphoric acid. In group 2, 24 teeth were prepared with a 1/4-round bur in a low-speed handpiece and then acid etched. In group 3, 24 teeth were prepared by high-speed (160 PSI) microabrasion using 50 mu alpha alumina particles in a KCP 2000 machine. In each group, 12 teeth were sealed with a filled sealant and 12 teeth with an unfilled sealant. All the teeth were stored in artificial saliva for 7 days and thermocycled for 2000 cycles. Teeth were then sealed apically and coated with nail varnish 1 mm from the margins and stained in 1% methylene blue for 24 h. Each tooth was sectioned in three locations and ranked (0-3) for microleakage. RESULTS: There were 216 sections and 66% showed no leakage. CONCLUSIONS: Chi-square statistical analysis of the data led to the following conclusions: 1) superior results were obtained when the tooth surfaces were prepared by a bur, 2) conventionally and KCP 2000-prepared tooth surfaces yielded similar results, and 3) the unfilled sealant was superior to the filled sealant.

Acid Etching, Dental↗