Individual, familial and country-level factors associated with oral hygiene practices in children: an international survey

BACKGROUND

Maintaining good oral hygiene is key to preventing dental caries and periodontal disease. Children and adolescents with good oral hygiene behaviours are likely to grow into adults with the same behaviours. This study assessed the frequency of using various oral hygiene methods among children and adolescents from different countries and individual, familial and country-level factors associated with the use of these methods.

METHODS

A multi-country online survey collected data from caregivers of children in 2020-21 about children's use of oral hygiene methods including toothbrush, fluoridated toothpaste, mouthwash, dental floss and miswak using self-administered, close-ended questions. Adjusted multilevel logistic regression models were used to assess the relationship between each of the five oral hygiene methods (dependent variables) and the independent factors: sex, age, and history of dental visits (individual factors), mother's education and area of residence (familial factors) as well as country income and region (country-level factors).

RESULTS

A total of 4766 parents/caregivers were included from 20 countries (77.4% Eastern Mediterranean-region and 41.6% lower middle income countries). The most frequent oral hygiene methods were using toothbrush and toothpaste (90% and 60.3%). The use of oral hygiene methods differed by age, sex and history of dental visits as well as mother's education and area of residence (P < 0.05). In addition, children from low income countries had significantly lower odds of using mouthwashes and dental floss than those from high income countries (AOR = 0.55, 95% CI 0.31, 0.98 and AOR = 0.34, 95% CI 0.12, 0.97) whereas children from the European region had higher odds of using mouthwash (AOR = 2.82, 95% CI 1.27, 6.26) and those from the region of the Americas had higher odds of using dental floss (AOR = 3.84, 95% CI 1.28, 11.52) than those from the Eastern Mediterranean region.

CONCLUSIONS

The use of various oral hygiene methods is associated with individual, familial and country-level factors. Oral health promotion programs should be developed taking into account these influences.

Evaluation of "Golden Proportion" in Saudi individuals with natural smiles

Background

The Golden Proportion (GP) has been considered by many as the most harmonious recurrent tooth-to-tooth ratio and has long been proposed as an aesthetic guideline for restoring/replacing maxillary anterior teeth. Researchers investigated GP in various populations.

Purpose

The aim of the current study was to investigate the occurrence and prevalence of the GP between the perceived widths of maxillary anterior teeth in a Saudi population with natural smiles.

Materials and Methods

A total of 360 Saudi dental students (180 males and 180 females) with natural smiles and who met the inclusion criteria were included in the study. Frontal photographs were captured for all participants while maximally smiling using a digital camera with standardized settings. Photo-editing software was used to measure the perceived mesiodistal width of each anterior maxillary tooth in all digital images. Paired and student t-tests were performed to detect side and/or gender differences respectively. Calculated ratios of the perceived mesiodistal widths of the teeth were compared with their respective GP values using a one sample t-test. Statistical significance was set at 5%.

Results

For both genders, there were significant differences (P < 0.001) between the calculated ratios and the golden ratios. No side differences in the GP were detected. Males had wider teeth than females however significant differences between genders was detected for the centrals (P < 0.001) only.

Conclusions

Width ratios of the maxillary anterior teeth did not follow the GP for the examined Saudi population. Males had wider anterior teeth with the centrals exhibiting a significant gender-based difference. There was no side-dependent variation for both genders.

Effect of total occlusal convergence on fit and fracture resistance of zirconia-reinforced lithium silicate crowns

Introduction

Computer-aided design (CAD) and computer-aided manufacturing (CAM) monolithic crowns are gaining momentum. Limited evidence exists about the effect of tooth preparation total occlusal convergence (TOC) on marginal and internal gap distances in addition to load to fracture values.

Aim

The aim of this study was to evaluate, by microcomputed tomography (µCT), the influence of 12° and 20° TOC on marginal and internal adaptation of zirconia-reinforced lithium silicate (ZLS) crowns. Moreover, values of load to fracture with and without initial cyclic loading (CL) were compared.

Material and methods

Forty ZLS crowns were fabricated on dies with TOC of 12° and 20°, 20 crowns for each group. µCT was used to compare marginal and internal adaptation. Each specimen was measured at 140 points distributed on all tooth preparation surfaces for 2D gap distance assessment. 3D gap volume was also evaluated. Crowns were then cemented and divided into two subgroups; the first was stored in distilled water (no cyclic loading [NCL] subgroup), the second was subjected to CL (CL subgroup).

Results

Factorial repeated measures ANOVA followed by Bonferroni post hoc in addition to independent and dependent t-tests were used for statistical analysis. Marginal gap, absolute marginal discrepancy, and occlusal gap measurements showed significant differences between the measurement sites. Static load to fracture values showed significant differences between TOC groups for both NCL (P=0.011) and CL (P=0.025) subgroups.

Conclusion

An increase of TOC from 12° to 20° did not affect marginal and internal adaptation but resulted in higher values of load to fracture of ZLS crowns. CL simulating 1 year of service did not result in fatigue failure.

Surface roughness and internal porosity of partial removable dental prosthesis frameworks fabricated from conventional wax and light-polymerized patterns: a comparative study

STATEMENT OF PROBLEM

Surface roughness and internal porosity are 2 potential risk factors that threaten the biocompatibility and long-term mechanical stability of cast partial removable dental prostheses frameworks.

PURPOSE

The purpose of this study was to investigate the influence of the material, of conventional wax patterns, and the recently introduced light-polymerized patterns on the initial surface roughness and internal porosity of the cobalt-chromium castings of partial removable dental prostheses.

MATERIAL AND METHODS

Twenty-eight identical partial removable dental prosthesis frameworks were fabricated on a cast of a maxillary Kennedy Class III modification 1 partially edentulous patient. Fourteen frameworks were fabricated from each pattern material. The initial surface roughness, Ra (μm), of the resultant castings was measured with a profilometer. Radiographs of the castings were made on dental occlusal films with a dental x-ray unit with the following exposure conditions: tube voltage 70 kV; exposure time 1.0 seconds; tube current 7 mA; and source-film distance 35 cm. The number and size of porosities in the 3 main components (clasp units, major connectors, denture base meshwork) were assessed. Statistical analysis was conducted with the independent sample t test for surface roughness and the Mann Whitney test for internal porosity (α=.05).

RESULTS

The statistical analysis of mean surface roughness and internal porosity revealed no significant difference between the 2 groups.

CONCLUSIONS

The surface roughness and internal porosity of frameworks fabricated from conventional wax and Liwa patterns were comparable, with no significant differences between the 2 pattern materials.

Setting up of teeth in the neutral zone and its effect on speech

Rational goals for denture construction are basically directed at the restoration of esthetics and masticatory function and the healthy preservation of the remaining natural tissues. Little concern has been given to the perfection and optimization of the phonetic quality of denture users. However, insertion of prosthodontic restorations may lead to speech defects. Most such defects are mild but, nevertheless, can be a source of concern to the patient. For the dental practitioner, there are few guidelines for designing a prosthetic restoration with maximum phonetic success. One of these guidelines involves the setting up of teeth within the neutral zone. The aim of this study was to evaluate, subjectively and objectively, the effect on speech of setting up teeth in the neutral zone. Three groups were examined: group I (control) included 10 completely dentulous subjects, group II included 10 completely edentulous patients with conventional dentures, and group III included the same 10 edentulous patients with neutral zone dentures. Subjective assessment included patient satisfaction. Objective assessment included duration taken for recitation of Al-Fateha and acoustic analysis. Subjectively, patients were more satisfied with their neutral zone dentures. Objectively, speech produced with the neutral zone dentures was closer to normal than speech with conventional dentures.