Determination of approximate size of maxillary anterior denture teeth when mandibular anterior teeth are present. Part III: Relationship of maxillary to mandibular central incisor widths

A Digital Way for Fabricating a Resin-Bonded Fixed Partial Denture Combined with Periodontal Splint in the Mandibular Anterior Region

Teeth loosening are caused by insufficient supporting tissue, inflammation of periodontal tissue, or occlusal trauma, which is one of the main clinical symptoms of periodontitis. A digital technique for fabricating resin-bonded splinting fixed partial dentures (S-FPDs) is presented. It restores the missing mandible anterior teeth and splints the adjacent periodontally mobile teeth of the patient at the same time. The S-FPDs is designed and fabricated by computer-aided design and computer-aided manufacturing (CAD/CAM) technology with flexible PMMA material. The workflow is straightforward, convenient, and accurate. Meanwhile, the restoration can meet the esthetic requirements and help with the stability of adjacent loosening natural teeth spontaneously. It could be considered a medium-term provisional restorative treatment option, but further controlled investigations still be needed.

Comparison Between Human Maxillary Anterior Teeth and Commercial Acrylic Teeth: A Sex-Stratified Analysis

Objective:

The aim of this study was 1.To compare the total width of human anterior teeth from different races (White, black, and Asian) to the total width of commercially available anterior teeth molds and, 2. To compare the width and length of human central incisors (#9) from different races (White, black, and Asian) with those of commercially available central incisors (#9).

Materials and Methods:

The study consisted of 360 participants, with 60 females and 60 males in each of 3 racial groups: White, Black, and Asian. Metric measurements of natural teeth were obtained from dental casts, and those of acrylic teeth were obtained from company catalogs.

Statistical Analysis:

Data normality was determined by Kolmogorov-Smirnov and Shapiro-Wilk tests. The Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner post hoc tests were used to compare measurements across the racial groups and commercial acrylic teeth. P value of ≤ 0.05 was set as statistically significant.

Results:

The results showed significant intra- and intergroup differences between males and females and across the 3 racial groups, especially among the Black group. Significant differences were also detected between artificial and natural teeth dimensions.

Conclusion:

Although similarities exist, generally, the dimensions of commercially available artificial teeth are different than that of natural teeth in the studied populations. Overall, in both males and females, the median length of natural tooth #9 is always smaller when compared to commercially available teeth. In contrast, in both males and females, the median width of natural tooth #9 is always larger when compared to commercially available teeth, except for female Asian population. Overall, significant racial differences exist in the length, width, and total width of natural teeth compared to commercially available teeth in the Black population. However, both the white and asian population showed less significant differences when comparing the length, width, and total width of natural teeth to commercially available teeth.

Comparative measurement of mesiodistal width of six anterior maxillary and mandibular teeth in rajasthan population

The purpose of the study was to determine the mesiodistal width of six anterior teeth for better esthetics and good tooth arrangement in a cross section of Rajasthan population. The mesiodistal dimension of central, lateral incisor and canine on right and left sides was measured in 250 males and 250 females, these readings were used to determine the mean, minimum and maximum maxillary/mandibular teeth 'anterior ratio', difference in mesiodistal width, combined mean mesiodistal width, the number and percent of similar teeth of maxilla and mandible. It was observed from the present study that there is variation in mesiodistal width in right and left sides signifying that the anterior teeth are not mirror images of one another. Male subjects have greater mesiodistal width than female subjects and right side dominates in most of the readings indicating that mesiodistal width is greater on right side than on left side. Percentage variability and sexual dimorphism are also important findings of this study. This study can prove helpful in replacement of artificial teeth of prosthesis in this cross section of population.

Dimensional changes of extended-pour alginate impression materials

INTRODUCTION

Recently, manufacturers have marketed alginate impression materials, claiming dimensional stability for up to 100 hours to allow shipping to a dental laboratory for digital model fabrication. The purpose of this study was to evaluate the dimensional changes of these newer materials after storage at different temperatures and times.

METHODS

Two extended-pour alginates (claiming 100 hours of accuracy) (Kromopan; Lascod, Florence, Italy; and Triphasix; Parkell, Edgewood, NY), 2 traditional alginates (Jeltrate; Dentsply-Caulk, York, Pa; and Kromatica; Matech, Sylmar, Calif), and 1 vinyl polysiloxane (VP Mix; Henry Schein, Melville, NY) were used to impress a scored aluminum die. The distance between the score lines was measured on the impressions at 10 minutes, 24 hours, and 100 hours after mix, and the percentages of dimensional change were calculated. Temperature effects were studied by storage at cold (-9°C), room (22°C), or hot (46°C) temperatures for 8 hours.

RESULTS

All alginates had statistically significant dimensional changes at 24 and 100 hours (0.69%-6.13%). VP Mix exhibited no statistically significant changes for any storage condition. The Kromopan (100 hour) and Kromatica (traditional) alginates were the most stable (0.85%-2.22% at 100 hours). Triphasix (100 hour) and Jeltrate (traditional) were the least stable (1.53%-4.73% at 100 hours). Cold-temperature storage resulted in the most dimensional changes (1.96%-4.73% at 100 hours). Room-temperature storage resulted in the least dimensional changes (0.97%-1.53% at 100 hours).

CONCLUSIONS

All alginate impression materials in the study had significant changes at 24 and 100 hours in all storage conditions tested.

Quantifying the selection of maxillary anterior teeth using intraoral and extraoral anatomical landmarks

BACKGROUND

One of the major hurdles in clinical prosthodontics has been the selection and replacement of maxillary anterior teeth in the absence of pre-extraction records. The aim of this study was to determine if a relationship exists between intraoral and extraoral facial measurements that could assist dental practitioners in selecting esthetically appropriate maxillary anterior teeth in the absence of pre-extraction records.

MATERIALS AND METHODS

A cross-sectional study design was used with a sample size of one hundred and twenty participants. A questionnaire was used to identify the selection criteria and a photograph was taken for facial measurements using digitally calibrated software. Ninety-eight participants met the selection criteria and were included in the study. Measurements of intraoral landmarks were taken from stone casts of maxillary impressions using calibrated digital calipers. Each measurement was completed by two assessors to obtain mean values. Data were statistically analyzed using SPSS version 17 software. Data were assessed by one way analysis of variance (ANOVA) followed by post hoc (p < 0.05) to find any difference between tested groups. Pearson coefficients were used to determine whether correlation exists between measurements.

RESULTS

The mean values for intraoral maxillary landmarks were: Central incisor width = 8.39 mm, circumferential canine tip to canine tip distance = 34.89 mm, arch width = 48.24 mm, left arch length = 45.24 mm, right arch length = 45.56 mm. The mean values for extraoral landmarks were: Intercanthal distance = 33.24 mm, interpupillary distance = 60.68 mm, interalar distance = 38.27 mm, intercommissure distance = 50.61 mm. Differences existed within subgroups for all intraoral and extraoral measures. A weak positive correlation existed between intraoral (r < 0.4) and extraoral measurements (r < 0.38) that remained consistent when examined by gender.

CONCLUSION

This study showed that the average length and width of the maxillary arch and interalar width were the anatomical landmarks that provided the strongest predictive relationship with anterior maxillary teeth (r = 0.38 - 0.4). Using these dimensions an average multiplying factor can be used to calculate maxillary incisor width or canine tip to canine tip distance. As the predictive strength is not strong, the authors recommend its use as a preliminary guide for determining the width of the maxillary anterior teeth during the initial selection of artificial teeth in the absence of pre-extraction records.

CLINICAL SIGNIFICANCE

The results of this study can be used to help dentists select the size of artificial maxillary anterior teeth in the absence of pre-extraction records.