Does the gender of the subject affect perceived smile aesthetics when varying the dimensions of maxillary lateral incisors?

Analysis of recurrent esthetic dental proportion of natural maxillary anterior teeth: A systematic review

STATEMENT OF PROBLEM

The recurrent esthetic dental (RED) proportion has been a benchmark for the rehabilitation of the maxillary anterior teeth of North American patients. While it has been evaluated in other populations, the global application of RED proportions in the rehabilitation of maxillary anterior teeth is unclear.

PURPOSE

The purpose of this systematic review was to examine the existing evidence on dental proportion to evaluate the existence of RED proportions in the esthetic smile in different geographic regions.

MATERIAL AND METHODS

A systematic search was conducted by reviewing different databases. The focused question was "Does RED proportion exist in esthetically pleasing smiles in different populations around the world?" The search included articles with a combination of MeSH keywords based on dental proportion from January 2000 to July 2020. The titles and abstracts were identified by using a search protocol. Full text of the articles was independently evaluated. The systematic review was modified to summarize the relevant data. The general characteristics, outcomes, and quality of studies were reviewed and analyzed systematically.

RESULTS

Seventeen studies were selected from the reviewed articles. Three studies were conducted in Europe, 10 in South Asia, and 4 in Western Asia. Eleven studies found that the mean perceived ratio of anterior teeth was not constant when progressing distally. Five studies reported that the ratio was constant in a small percentage of their populations, and 1 suggested that the ratio was constant if it remains between 60% and 80%. The central-to-LI and Ca-to-LI proportion values were not constant. Overall, the Ca-to-LI proportion values were higher than the central-to-LI proportions.

CONCLUSIONS

RED proportions were not found in the successive widths of maxillary anterior teeth among the reviewed data from different geographic regions. RED proportions are not the only standard for restoring esthetic smiles worldwide, and anterior tooth proportions differ among populations based on their race and ethnicity.

Esthetic Perception of Different Clinical Situations of Maxillary Lateral Incisor Agenesis According to Populations with Dental and Non-Dental Backgrounds: A Systematic Review and Meta-Analysis

Treatment of unilateral or bilateral maxillary lateral incisor agenesis is challenging, time-consuming, expensive, and requires careful treatment planning, predictability, and esthetics. This review aimed to identify differences in esthetic perception among orthodontists, general dentists, differentiated dentists, and laypersons, which may interfere with treatment options. EBSCO, PubMed, ScienceDirect, Cochrane Library databases, and Google Scholar were searched using keyword pairing and a Boolean expression, "(congenitally missing OR agenesis OR hypodontia) AND (maxillary lateral incisors) AND (esthetic perception OR smile) AND (laypersons OR dental professional OR general dentist OR orthodontists)." Reviews and case studies were excluded. A total of 13 studies were selected for qualitative analysis (adapted ROBINS-I) and 11 were selected for meta-analysis (p < 0.05) after being sub-grouped into "Opening vs. Closure" and "No remodeling vs. Dental remodeling vs. Dental and gingival remodeling" groups. A meta-analysis evaluated the magnitude of the difference between groups based on differences in means and effect sizes (α = 0.05; 95% CI; Z-value 1.96), revealing that the esthetic perception of maxillary lateral incisor agenesis treatment remains controversial even among professionals. Gingival remodeling was not valued compared to isolated dental remodeling. Studies lack rigorously comparable methodologies. Discussion with the patient is pertinent in doubtful situations, as the best treatment option remains unclear, and overtreatment should be avoided.

Assessment of Golden Proportion among Natural Maxillary Anterior Teeth of Global Population: A Systematic Review

The purpose of this systematic review was to analyze studies, identify the existence of golden proportion between the perceived widths of the maxillary anterior teeth among the different geographical populations, and evaluate the range of dental proportion that exists regionally. An electronic search was conducted using PubMed, Medline, EMBASE, Scopus, Science Direct, Web of Science, and the Cochrane Library. The focused question was, “Does golden proportion exist in natural, aesthetically pleasing smiles among different populations around the world?” The search conducted included studies from January 2000 to September 2020, identifying articles in English with the specific combination of MeSH and other related terms. The title search yielded eight hundred and ninety-eight articles, and seventy-five articles were selected for full-text analysis. However, only fifty-two full-text articles were included in the systematic review. The mean predicted dental ratios were either larger or smaller than the successive widths of maxillary natural anterior teeth. Golden proportions were not found consistently among anterior teeth in different populations observed in the systematic review. The golden proportion is still a useful tool for the reconstruction of lost or damaged anterior tooth widths; however, it is not the only standard for restoring esthetic smiles worldwide, and anterior tooth proportions differ among populations based on their geographic, ethnic, and racial background. Moreover, consideration should also be given to an individual’s dentofacial variations in restoring anterior teeth.

Esthetic and functional rehabilitation of peg-shaped maxillary lateral incisors: Practical recommendations

Peg-shaped maxillary lateral incisors cause many functional and esthetic major consequences in affected patients. Their esthetic and functional rehabilitations are often multidisciplinary, involving different clinical procedures like periodontal, orthodontic, or prosthodontic procedures. No exhaustive protocol has been established to improve their comprehensive management by general dentists or specialists. The aim of this article is to elaborate a simplified clinical protocol of complete management of peg-shaped maxillary lateral incisors by a multidisciplinary team (general practitioners, orthodontists, and prosthodontists). A clinical case of two peg-shaped maxillary lateral incisors completely rehabilitated with multidisciplinary approaches including orthodontic treatment and restoration by veneers and direct composite resin, according to the established protocol. Extraoral, intraoral, and smile clinical analysis are crucial to ensure optimal rehabilitation. Treatment results previsualization via wax-up and/or mock-up play a key role in the communication between practitioner and patient to help the latter make decision. These options also facilitate the achievement of a multidisciplinary approach by accurately estimating the number of dental movements and the type of restorations that are most suitable to the presenting clinical situation.

Analysis of the esthetic preferences of Spanish laypersons and dentists regarding the different width proportions of the maxillary anterior teeth

STATEMENT OF PROBLEM

Multiple esthetic width proportions have been described for maxillary anterior teeth. However, the esthetic characteristics of each have not been compared simultaneously to determine which proportion is preferred by dentists and laypersons.

PURPOSE

The purpose of this study was to evaluate the preferences of dentists and laypersons with respect to internationally recognized dental esthetic proportions. It also sought to determine whether a relationship existed among dentists' preferences as per their specialty and among laypersons as per their academic field.

MATERIAL AND METHODS

Two smile images, one male and one female, were digitally modified to meet the golden proportion and the recurring esthetic dental (70%) and golden percentage. The 2 resulting sets of images (original images and digitally altered ones) were presented to dentists and laypersons through a Web-based survey site. The Pearson chi-squared and Fisher tests were used to assess the differences in the esthetic preferences among the groups (α=.05).

RESULTS

A total of 363 answers were obtained from dentists and 750 from laypersons. Both groups considered recurring esthetic dental to be the most esthetic proportion and golden proportion to be the least esthetic proportion. The dentists' preferences as per their specialty followed the same trend, whereas the laypersons' preferences were more scattered according to their academic field. The recurring esthetic dental proportion was preferred in images of both sexes, golden proportion smiles were the least preferred for female smiles, and golden percentage was the least preferred for male smiles.

CONCLUSIONS

The results obtained indicated that the preferred esthetic proportion both for dentists and laypersons was the recurring esthetic dental 70%, with the dentists' specialty or laypersons branch of knowledge not affecting choice.

Evaluation of golden percentage in natural maxillary anterior teeth width: A systematic review

STATEMENT OF PROBLEM

The color and form of teeth are 2 of the 3 main determinants of success in an esthetic restoration; the third is dental proportion. A recent systematic review of the literature devoted to the evaluation of dental proportion is lacking.

PURPOSE

The purpose of this systematic review was to investigate the quality and outcome of studies into maxillary anterior tooth proportion and to determine whether dental proportion ratios based on different geographic regions are appropriate.

MATERIAL AND METHODS

An electronic search was conducted using PubMed, MEDLINE, Google Scholar, Embase, Scopus, Cochrane Library, Web of Science, and Science Direct databases. English-language articles reporting with the specific combination of medical subject heading (MeSH) key words were analyzed by 2 investigators. The titles, full text, and abstracts were scanned by investigators independently to identify articles that fulfilled the inclusion criteria. The general characteristics, outcomes, and quality of each study were reviewed and analyzed systematically.

RESULTS

The search plan resulted in a total of 73 articles until September 2020; of which, 16 articles fulfilling the inclusion criteria were selected. The geographic distribution of the selected article revealed 12 articles from Asia, 2 from Continental Europe, and 2 from the United Kingdom. Golden percentage values of 25%, 15%, and 10% for central, lateral incisor, and canine teeth were not found. The mean predicted dental percentage was either larger or smaller than the successive widths of maxillary natural anterior teeth.

CONCLUSIONS

The golden percentage could not be used to formulate a smile design. Rather, the dental ratios should be set on a racial and ethnic basis for a population.