Lay preferences for dentogingival esthetic parameters: A systematic review

Effect of sintering on the translucency of CAD-CAM lithium disilicate restorations: A comparative in vitro study

PURPOSE

The available independent data on the translucency of novel pre and fully sintered chairside computer-aided design and computer-aided manufacturing (CAD-CAM) lithium disilicate are limited. This comparative in vitro study evaluated the translucency degree of pre and fully sintered chairside CAD-CAM lithium disilicate crowns after optional, required, and additional firing processes.

MATERIALS AND METHODS

One hundred and five maxillary left central incisor crowns manufactured by three different CAD-CAM lithium disilicate brands shade A1 were assigned into seven groups as follows (n = 15): (1) Straumann n!ce without sintering; (2) Straumann n!ce with one additional sintering process; (3) Straumann n!ce with two additional sintering processes; (4) Amber Mill with one sintering process; (5) Amber Mill with two sintering processes; (6) IPS e.max CAD with one sintering process; and (7) IPS e.max CAD with two sintering processes. The translucency of all crowns was evaluated with a color imaging spectrophotometer. All statistical analyses were performed using statistical software. A standard level of significance was set at α < 0.05.

RESULTS

All the milled crowns presented different degrees of translucency, and additional sintering processes altered it. IPS e.max CAD with two (4.33 ± 0.26) and one (4.01 ± 0.15) sintering processes displayed the highest translucency, whereas Straumann n!ce with no sintering process provided the lowest value (2.82 ± 0.16).

CONCLUSIONS

The translucency of chairside lithium disilicate single-unit full-coverage restorations manufactured with subtractive technology was significantly influenced by the brand and the number of sintering processes. The traditional presintered IPS e.max CAD and the fully crystallized glass-ceramic Straumann n!ce considerably increased the translucency after one additional firing process, whereas Amber Mill decreased its translucency.

Printed Digital Wax-up Model as a Blueprint for Layered Pressed-ceramic Laminate Veneers: Technique Description and Case Report

This article presents a clinical technique for transferring Digital Smile Design (DSD) information and a digital wax-up to fabricate highly personalized ceramic laminate veneers. The hybrid workflow of digitally designed wax-up and conventional hand-crafted veneers is showcased in a female adult who sought to improve her smile due to maxillary anterior incisal wear. The ceramic veneers, layered by feldspathic porcelain, followed the contours and shade blueprint planned with the digital wax-up. The DSD improved the harmony of the facial-and-smile relationship, and the ceramic restorations fulfilled the patient's esthetic and functional demands. Guides based on the printed model with the digitally designed wax-up can provide a reference for pressed lithium disilicate veneers layered with feldspathic porcelain.

Comparison of maxillary anterior mathematical proportions among 3 dental arch forms

STATEMENT OF PROBLEM

Race and sex differences in the mathematical proportions of maxillary anterior teeth have been evaluated. However, studies exploring the relationship between the mathematical proportion of maxillary anterior teeth and maxillary dental arch form are lacking.

PURPOSE

The purpose of this clinical study was to determine if a correlation exists between the mathematical proportions of maxillary anterior teeth and 3 dental arch forms.

MATERIAL AND METHODS

Three hundred young participants were recruited according to predefined criteria, and images and maxillary casts were obtained. The perceived width and length of the maxillary anterior teeth were measured on the images by using a software program, and mathematical proportions, including width ratios and width-to-length ratios, were calculated for each. The casts were used to categorize each specimen into tapered, ovoid, or square groups by using a specific classification method, and the width ratios and width-to-height ratios of the 3 dental arch forms were compared. Statistical analysis was performed by using analysis of variance (ANOVA) or the Kruskal-Wallis H test to compare the mathematical proportions of maxillary anterior teeth among the 3 dental arch forms (α=.05). The intraclass correlation coefficient (ICC) was used to test the reliability of the investigators.

RESULTS

Except for the width-to-length ratios of the central incisor, mathematical proportions were affected by the dental arch form. The perceived width ratios of the maxillary lateral incisor-to-central incisor gradually increased from the tapered arch to the ovoid arch and from the ovoid arch to the square arch, with mean ±standard deviation values of 0.71 ±0.04, 0.73 ±0.05, and 0.79 ±0.06, respectively. For the maxillary perceived width ratios of canine-to-lateral incisor, the ovoid arch had the maximum perceived width ratios (0.86 ±0.10), followed by the tapered (0.82 ±0.10) and square arches (0.77 ±0.11). The width-to-length ratios of the central incisor were not affected by the arch form (P=.075), and the width-to-length ratios of the lateral incisor increased as the arch form became flat, with respective values of 0.70 ±0.10, 0.74 ±0.10, and 0.76 ±0.10. For the width-to-length ratios of the canine, the ovoid arch had the maximum perceived width ratios (0.58 ±0.10), followed by the tapered (0.53 ±0.10) and square arches (0.52 ±0.10).

CONCLUSIONS

The mathematical proportions varied among the 3 dental arch forms, and the dental arch form should be considered during the prosthodontic design of maxillary anterior teeth.

The relationship of tooth crown dimensions between first molar and central incisor in maxilla

The purpose of this study was to investigate a correlation between the cusp dimensions of the first molar and mesiodistal crown diameters of the central incisors in the maxilla. The study materials were composed of dental casts from 29 modern Japanese female subjects with a mean age of 20 years and 8 months. The mesiodistal crown diameters of the maxillary central incisors were measured. The mesiodistal and bucco-lingual crown diameters and the cusp diameters of the maxillary first molars, such as the paracone, metacone, protocone, and hypocone, were also measured. The crown areas and indices of the first molars were calculated. The Spearman's single rank correlation coefficients between the mean values for the crown dimensions of the first molars and the mesiodistal crown diameters of the central incisors were calculated. The hypocone cusp diameter and the hypocone index were the largest compared to those of the paracone, protocone, and metacone cusps. The bucco-lingual diameter and hypocone cusp diameter of the first molars positively correlated with the mesiodistal crown diameters of the central incisors on the same sides. There were positive correlations between the hypocone index of the first molars and the mesiodistal crown diameters of the central incisors. Based on the results, if a large hypocone is observed in eruption of the maxillary first molars, it will be predictable that of the mesiodistal crown diameter of the maxillary central incisor large.

Revised FDI criteria for evaluating direct and indirect dental restorations-recommendations for its clinical use, interpretation, and reporting

OBJECTIVES

The FDI criteria for the evaluation of direct and indirect dental restorations were first published in 2007 and updated in 2010. Meanwhile, their scientific use increased steadily, but several questions from users justified some clarification and improvement of the living document.

MATERIALS AND METHODS

An expert panel (N = 10) initiated the revision and consensus process that included a kick-off workshop and multiple online meetings by using the Delphi method. During and after each round of discussion, all opinions were collected, and the aggregated summary was presented to the experts aiming to adjust the wording of the criteria as precisely as possible. Finally, the expert panel agreed on the revision.

RESULTS

Some categories were redefined, ambiguities were cleared, and the descriptions of all scores were harmonized to cross-link different clinical situations with possible management strategies: reviewing/monitoring (score 1-4), refurbishment/reseal (score 3), repair (score 4), and replacement (score 5). Functional properties (domain F: fracture of material and retention, marginal adaptation, proximal contact, form and contour, occlusion and wear) were now placed at the beginning followed by biological (domain B: caries at restoration margin, hard tissue defects, postoperative hypersensitivity) and aesthetic characteristics (domain A: surface luster and texture, marginal staining, color match).

CONCLUSION

The most frequently used eleven categories of the FDI criteria set were revised for better understanding and handling.

CLINICAL RELEVANCE

The improved description and structuring of the criteria may help to standardize the evaluation of direct and indirect restorations and may enhance their acceptance by researchers, teachers, and dental practitioners.

Soft Tissue Grafting Procedures before Restorations in the Esthetic Zone: A Minimally Invasive Interdisciplinary Case Report

An esthetically pleasing smile is a valuable aspect of physical appearance and plays a significant role in social interaction. Achieving the perfect balance between extraoral and intraoral tissues is essential for a harmonious and attractive smile. However, certain intraoral deficiencies, such as non-carious cervical lesions and gingival recession, can severely compromise the overall aesthetics, particularly in the anterior zone. Addressing such conditions requires careful planning and meticulous execution of both surgical and restorative procedures. This interdisciplinary clinical report presents a complex case of a patient with esthetic complaints related to asymmetric anterior gingival architecture and severely discolored and eroded maxillary anterior teeth. The patient was treated using a combination of minimally invasive ceramic veneers and plastic mucogingival surgery, resulting in a successful outcome. The report emphasizes the potential of this approach in achieving optimal esthetic results in challenging cases, highlighting the importance of an interdisciplinary team approach in achieving a harmonious balance between dental and soft tissue aesthetics.

Minimally Invasive Laminate Veneer Therapy for Maxillary Central Incisors

Minimally invasive dentistry is a considered process that requires the clinician to be prepared with the ideal sequence and the tools needed. This report describes a well-planned ultraconservative approach using only two ceramic laminate veneers for the maxillary central incisors to significantly improve the patient's overall smile. A 30-year-old female presented with the chief complaints of having diastemas between the central and lateral incisors as well as incisal wear. Diagnostic wax-up and mock-up were performed, and the patient approved the minimally invasive treatment with veneers only for central incisors. A reduction guide aided the conservative tooth preparations, and hand-crafted feldspathic veneers were bonded under total isolation with a rubber dam. The two final conservative veneers significantly improved the smile and fulfilled the patient's expectations. Following proper planning and sequencing, predictable outcomes were obtained and fulfilled the patient's esthetic demands. Minimally invasive restorative dentistry with only two single veneers can impact the entire smile frame. Overtreatment in the esthetic zone is unnecessary to meet a patient's esthetic expectations.

Effect of smile esthetics on the quality of life in a Han Chinese population

OBJECTIVE

This study aimed to explore the influence of smile esthetics on the quality of life in a Han Chinese population.

METHODS

A total of 110 Han Chinese volunteers (52 males and 58 females, mean age 26.7 years) were recruited, and frontal images of their smiles were collected. A photoediting program was used to evaluate the following components of smile esthetics: the buccal corridor ratios, the angle between the interpupillary and commissural lines, the number of visible teeth, and width-to-length ratios of the maxillary central incisors. Oral health-related quality of life (OHRQoL) in these volunteers was evaluated using the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and Oral Health Impact Profile-14 (OHIP-14). Statistical analyses were performed by using Pearson's correlations and multiple linear regression (α = 0.05).

RESULTS

Compared to males, females scored higher on psychological impact (p = 0.017). Moreover, the number of visible teeth had a significant effect on social impact, psychological impact and esthetic concern (all p < 0.05). However, the buccal corridor ratios, the angle between the interpupillary and commissural lines, and the width-to-length ratios of the maxillary central incisor did not correlate with the OHRQoL (all p > 0.05).

CONCLUSIONS

The number of visible teeth significantly influenced the quality of life in a Han Chinese population. Smile esthetics had a significantly greater psychological impact on females than males.

CLINICAL SIGNIFICANCE

This study highlights the effects of smile esthetics on the quality of life in a Han Chinese population. Female patients may raise more esthetic concerns in clinical practice.

Diagnostic Mock-Up as a Surgical Reduction Guide for Crown Lengthening: Technique Description and Case Report

Background and Objectives: The report describes a technique using a diagnostic mock-up as a crown-lengthening surgical guide to improve the gingival architecture. Materials and Methods: The patient's primary concern was improving her smile due to her "gummy smile" and short clinical crowns. After clinical evaluation, surgical crown lengthening accompanied by maxillary central full-coverage single-unit prostheses and lateral incisor veneers was recommended. The diagnostic mock-up was placed in the patient's maxillary anterior region and used as a soft tissue reduction guide for the gingivectomy. Once the planned gingival architecture was achieved, a flap was reflected to proceed with ostectomy in order to obtain an appropriate alveolar bone crest level using the overlay. After six months, all-ceramic crowns and porcelain veneers were provided as permanent restorations. Results: A diagnostic mock-up fabricated with a putty guide directly from the diagnostic wax-up can be an adequate surgical guide for crown-lengthening procedures. The diagnostic wax-up was used to fabricate the diagnostic mock-up. These results suggested that it can be used as a crown-lengthening surgical guide to modify the gingival architecture. Several advantages of the overlay used in the aesthetic complex case include: (1) providing a preview of potential restorative outcomes, (2) allowing for the appropriate positioning of gingival margins and the desired alveolar bone crest level for the crown-lengthening procedure, and (3) serving as a provisional restoration after surgery. Conclusions: The use of a diagnostic mock-up, which was based on a diagnostic wax-up, as the surgical guide resulted in successful crown lengthening and provisional restorations. Thus, a diagnostic overlay can be a viable option as a surgical guide for crown lengthening.

Fully Digital versus Conventional Workflows for Fabricating Posterior Three-Unit Implant-Supported Reconstructions: A Prospective Crossover Clinical Trial

This study assessed the clinical variables influencing the success of three-unit implant-supported fixed dental prostheses (ISFDPs) fabricated using either fully digital or conventional workflows. The clinical trial evaluated 10 patients requiring three-unit ISFDPs in the posterior mandible. Maxillomandibular relation records, and digital and conventional impressions were obtained from each patient using an intraoral scanner (IoS) and polyvinylsiloxane (PVS), and the frameworks were fabricated using zirconia and cobalt-chromium, respectively. A 2 µm accuracy scanner scanned the conventional master casts and standard reference models. The stereolithography (STL) files of the digital and conventional impressions were superimposed on the standard model file, and the accuracy was calculated with the best-fit algorithm. The framework adaptation and passivity were assessed using the one-screw and screw resistance tests. The time required for occlusal adjustment of both types of reconstructions, including the duration of the whole treatment, was recorded. The aesthetic appearance of ISFDPs was rated by each patient and clinician using a self-administered visual analogue scale questionnaire and the FDI World Dental Federation aesthetic parameters, respectively. The sample size was based on the power calculation, and alpha was set at 0.05 for the statistical analyses. The impression accuracy, framework adaptation and passivity, and reconstructions aesthetics did not significantly differ between the digital and conventional approaches. The total fabrication time was significantly shorter using the digital workflow. Within the limitations of this clinical study, the fully digital workflow can be used for the fabrication of ISFDPs with a clinical outcome comparable to that of the conventional workflow.

Smile Design: Mechanical Considerations

Smile designing refers to the cosmetic and esthetic dental reconstruction that is visible during smiling. The use of modern digital tools requires adequate knowledge about the tooth shape and shade principles. Mechanical, biological, and psychological factors should be understood and tailor an individualized treatment accordingly to achieve pleasing esthetic outcomes. Dental therapy is becoming more appearance-driven, and thus, both patients and dental clinicians mainly emphasize on cosmetic dental and facial aspects of treatments.

Various Aspects Involved in the Study of Tooth Bleaching Procedure: A Questionnaire–Based Study

A beautiful smile is an important feature when it comes to a pleasant appearance of the face, and one of the most common situations that drive patients to book a dental appointment is tooth discoloration. Tooth bleaching is the treatment of choice for extrinsic tooth discoloration, as it is a cheap, fast, and minimally invasive procedure. This study aimed to provide comparative information on the perceptions of both patients and dentists regarding different whitening methods and on the factors involved in people’s willingness to recommend and use a bleaching procedure. In addition to this, this study evaluated the degree of satisfaction in relation to the bleaching methods and materials used; it also evaluated the following: negative side effects, economic characteristics and the patients’ perceptions of the aesthetic appearance of their dental arches, especially tooth color. The subjects that participated in the present study were selected based on their background and were then divided into two categories. The first group consisted of 120 patients who had received tooth-bleaching treatments in dental clinics during the study and the second group consisted of 127 dentists. A conventional sampling method was used. The study aimed to define a relationship between multiple aspects of the tooth-bleaching procedure, including the patients’ desires and their general knowledge of this procedure. Tooth color and the way it changes is a very important factor that motivates patients to come to the dentist for whitening procedures. Patients showed the highest levels of satisfaction with the results of in-office bleaching procedures. In the group consisting of dentists, satisfaction levels were higher for the procedure of home bleaching supervised by a dentist. Factors influencing the choice of bleaching materials are appreciated differently by dentists and patients. Furthermore, the rate of patients using OTC (over the counter) products was found to be high. Further research is needed to find more effective and safer alternatives to home tooth-bleaching procedures.

A Cross-Sectional Online Survey on Knowledge, Awareness, and Perceptions of Hollywood Smile Among the Saudi Arabia Population

Background:

Hollywood smile has gained popularity in recent times to improve aesthetics among the general population. Since patients’ perceptions of dental aesthetics play a vital role in planning and evaluating cosmetic dental treatment, it is essential to understand their knowledge, awareness, and factors that influence their perceptions of dental aesthetics.

Objectives:

The objective of this study was to assess the knowledge, awareness, and perceptions of Hollywood smile among the general population in Saudi Arabia.

Methods:

A close-ended questionnaire consisting of demographic information and 20 questions related to Hollywood smile was circulated through social media in Saudi Arabia. Statistical analyses of the data obtained were performed using Statistical Package for Social Sciences software (SPSS version 17, USA). Frequencies, percentages, and mean and standard deviation were calculated using descriptive statistics. Pearson chi-squared test was employed to test the association between the demographic variables, such as age, gender, and education levels, with the questionnaire items.

Results:

A total of 4104 participants responded to the study questionnaire. The responses to the questionnaire revealed that nearly half of the participants were not satisfied with their dental appearance (48.6%). The majority of the participants had heard or known about Hollywood smile (98%). About 42% of study participants were aware of the complications involved in the procedure. The results revealed that the younger generation (18 to 30 years) had more awareness and felt more need for dental aesthetics (p=0.001). The proportion of male participants who underwent Hollywood smile correction were more than females (p=0.001). Graduates showed more awareness regarding smile, dental aesthetics, and Hollywood smile than the other categories (p=0.001).

Conclusion:

This study has shown that the younger generation, female participants, and graduates had more awareness regarding smile, dental aesthetics, and Hollywood smile.

The perception of smile attractiveness to altered vertical position of maxillary anteriors by various groups

There is a gap in research about the differences in smile attractiveness. The problem the study addresses is how the vertical canine and incisor position affect smile attractiveness. The aim of this study was to assess the perception of the smile attractiveness between Saudi laypersons, orthodontists, non-orthodontist, and various dental students levels, and to determine how the canine and incisor vertical positions affect the attractiveness of smile. The study is a cross-sectional survey and was conducted at King Abdulaziz University, Jeddah, Saudi Arabia. Six groups of subjects participated in the study: Orthodontic residents (n = 31), prosthodontic, restorative, periodontics specialties residents specialties residents (n = 30), interns (n = 31), fifth year students (n = 41), 6th year students (n = 39), and laypeople (n = 39). Participants were asked to rate the attractiveness of a smile of a female subject photographed using a Minolta DiMage 7i digital camera. The image had been manipulated to produce 2 sets of images; 1 to modify the incisors and 1 to change the canines. The subjects were asked to choose the most and least attractive picture. For the best incisor positions, only the laypeople and prosthodontics liked the original picture, the rest liked +0.5 mm which accentuate the smile curve and make it follow the lower lip line. For the worst incisor position, all groups did not prefer the minus 1.5 reversed smile. For the best canine vertical position, all groups preferred the original position where canine was at the level of the incisal plane. For the worst canine position, they all disliked the minus 1.5 reversed smile. Results confirmed past findings that orthodontists are in general more critical about smile attractiveness than laypersons, but just like other dental specialists. The findings can be used in the esthetic dentistry field, but further research on the study population based on other dental design parameters remain necessary.

I See Faces! A Review on Face Perception and Attractiveness with a Prosthodontic Peek at Cognitive Psychology

A human face contains a wealth of information about an individual, with which an observer can instinctively make a judgment on the attractiveness of the face. However, despite the profuse literature on facial and smile attractiveness, their origins, determinants, and perceptions remain controversial. The axiom in face processing research is that a face is perceived as an amalgamation of its features, and is referred to as "whole" or "holistic" perception. It is pertinent to the clinician involved in the provision of esthetic restorations to understand this holistic process of face recognition and perception of smile attractiveness. This review paper addresses face recognition and perception of attractiveness by reviewing the holistic perception of faces, including the multidimensional face-space model, and also reviews the smile and facial attractiveness according to the average, multiple motive, and secondary sex characteristics theories.

Analysis of the effect magnitude of different parameters on smile attractiveness

OBJECTIVE

To evaluate the effect magnitude of different parameters on smile attractiveness.

MATERIALS AND METHODS

A reference and 13 images were produced by manipulating 13 parameters. Image rating was performed with a 4-point Likert scale from least attractive (1) to most attractive (4). Image raters included laypeople, dental students, dentists, and dental specialists. Friedman and Wilcoxon image were used for estimate of effect size. Parameters were classified into small (0.10- < 0.30), medium (0.30- < 0.5), or large (≥0.50).

RESULTS

A total of 1040 people participated with good consistency (α = 0.861), and moderate reliability (0.64-0.7). The reference image had the highest rank (laypeople:11.79, dental background: 12.55). For effect size; gingival margin level (-0.11, -0.01), teeth width proportion (-0.09, -0.10), inverted smile arch (-0.09, -0.21), commissure line cant (-0.15, -0.17) and low smile (-0.24, -0.23) had small effect size; occlusal plane cant (-0.36, -0.49), midline cant (-0.36, -0.48), and midline shift (-0.37, -0.49) had medium effect size; diastema (-0.55, -0.54) and color (-0.56, -0.56) had large effect size for the laypeople and dental groups. High smile (-0.42, -0.51), incisor edge symmetry (-0.46, -0.54) had medium effect size in laypeople group and large effect size in the dental group. Width to length tooth proportion (-0.26, -0.39) had small effect size in the laypeople group and medium effect size in the dental group.

CONCLUSIONS

Smile parameters had different effect magnitude on smile attractiveness and were classified into small, medium, or large parameters. Neither laypeople nor professionals have a collective judgment on what constitutes a beautiful smile.

CLINICAL SIGNIFICANCE

This study investigated the effect magnitudes of 13 smile parameters and presented a small, medium, and large smile parameters classification. It should provide the clinician with an insight into the expected effect each parameter has on the smile.

Canadian Dental Patients with a Single-Unit Implant-Supported Restoration in the Aesthetic Region of the Mouth: Qualitative and Quantitative Patient-Reported Outcome Measures (PROMs)

This article contains quantitative and qualitative patient-reported outcome measures (PROMs) collected from nine dental patients, with a single-implant in the maxillary anterior region of the mouth, recruited after obtaining consent documents. The quantitative data were obtained from participants’ demographics, frontal extraoral digital photographs, intraoral scans (IOS) of the maxillary arch, and self-administered questionnaires (where patients judged the overall, appearance, function, and comfort of their single-implant-supported crowns). Objective single-implant aesthetic index mean scores (Pink Esthetic Score/White Esthetic Score [PES/WES]) were obtained after two experienced calibrated clinicians analyzed the photographs and the three-dimensional models generated from the IOS. The self-administered questionnaires used a visual analogue scale (VAS) to obtain the patients’ subjective perceptions. The qualitative data were obtained from in-depth, semi-structured one-to-one interviews. The transcriptions from audio-recorded interview data were managed and coded, with the aid of a Computer-Assisted Qualitative Data Analysis Software (CAQDAS). These data were stored in a public repository that can be easily downloaded from a Mendeley data repository (DOI: 10.17632/sv8t6tkvjv.1).

Influencing Factors on Aesthetics: Highly Controlled Study Based on Eye Movement and the Forensic Aspects in Computer-Based Assessment of Visual Appeal in Upper Front Teeth

First impressions are formed by the external appearance and, in this respect, essentially by an examination of the face. In the literature, the teeth, especially the maxillary front, are among an eye-catching and sensitive area that plays a significant role in the overall evaluation of appearance. In this study, the first eye fixation of 60 subjects with different levels of dental training (layperson, trained layperson, dental student, and dentist) is recorded using an eye-tracking system, and their subsequent evaluation of the images is recorded. Ten unedited original photographs of different maxillary anterior teeth and ten subsequently edited photographs will be used to evaluate forensic aspects such as the effect of symmetry and color on the overall evaluation. The results will be used to determine which areas of the maxillary anterior are demonstrably viewed and whether knowledge of dental esthetics influences evaluation and viewing.

Understanding the Lived Experience of North American Dental Patients With a Single-Tooth Implant in the Upper Front Region of the Mouth: Protocol for a Qualitative Study

BACKGROUND

Assessment of the subjective experiences of individuals with maxillary anterior (ie, the upper front region of the mouth) single-tooth implants is limited mainly to quantitative measurements of satisfaction with appearance. Interestingly, there is unexplained variability in the relationship between satisfaction and appearance.

OBJECTIVE

This qualitative study protocol aims to explore and better understand the satisfaction with appearance and function in a Canadian population with maxillary anterior single-tooth implants treated at a postgraduate university clinic. Thus, we aim to obtain diversity among participants relating to the identification of esthetically pleasing and displeasing cases from a clinician perspective.

METHODS

A qualitative research design using interpretative phenomenology analysis (IPA) will provide an adaptable inductive research approach. The participants will be recruited, and consent documents, photographs, digital intraoral scans, and self-administered questionnaire responses will be obtained from them. The transcribed verbatim data from audio-recorded, in-depth, semistructured, one-to-one interviews of the participants will be managed, coded, and analyzed thematically with computer-assisted qualitative data analysis software. The IPA will consider the COnsolidated criteria for REporting Qualitative (COREQ) guidelines when applicable.

RESULTS

For the qualitative interview, we plan to include at least eight patients to conduct up to 1.5 hours of open-ended interviews with each participant aided by an interview guide. Ethical approval was granted by the University of British Columbia Behavioral Research Ethics Board (H19-00107) in May 2019. Two American dental foundations funded this study.

CONCLUSIONS

The analysis in this study will elucidate the aspects (including their value) that influence participant satisfaction at different dental implant treatment stages. This will be the first qualitative study on this group of the population to explore and obtain a better understanding of their satisfaction with appearance and function, as well as any other patient-reported outcome measures that could be identified.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/25767.

Comparative analysis of smile aesthetics between top celebrity smile and a Southern European population

STATEMENT OF PROBLEM

The analysis of different parameters involved in the esthetic perception of the smile is important for the correct planning of cosmetic dental treatments.

PURPOSE

The purpose of this study was to analyze the differences in the main parameters of smile esthetics among celebrities identified as having the best esthetic smiles and a young Southern European population.

MATERIAL AND METHODS

The study consisted of a control group of 144 dental students from the University of Seville (69.4% women; 30.6% men) with a mean ±standard deviation age of 23.19 ±0.5 years and photographs of 58 celebrities identified as having the best esthetic smiles (74.1% women; 25.9% men) with a mean ±standard deviation age of 42.09 ±2.25 years. Photographs of the celebrities were obtained from the Internet, and standardized photographs were made of the control group. The variables measured were smile line, smile arc, incisal edges and lower lip relationship, smile width, dental midline deviation and tilting, buccal corridor widths, and angulation discrepancy between interpupillary line and commissural line and between interpupillary line and occlusal plane. The data obtained were processed in a statistical software program for a descriptive statistical analysis and for inferential analysis parametric statistical tests by applying the Wilcoxon, chi-square, Student t, and kappa index tests (α=.05).

RESULTS

Statistically significant differences (P<.01) were found between the groups in terms of smile width, smile arc, midline deviation and tilting, and angulation discrepancy between the interpupillary line and the commissural line. Smile arc was the only variable found to be different (P<.01) in relation to sex.

CONCLUSIONS

Characteristics of the most esthetic smiles were no deviation or tilting of the maxillary midline, showing a greater number of teeth in the smile, displaying incisal edges parallel to the lower lip (particularly in women), and displaying occlusal and commissural planes parallel to the interpupillary line.

Quantitating the art and science of esthetic clinical success

BACKGROUND

Beginning with the biobehavioral bases of esthetic experiences, this article presents a quantitative analytic review of the motives and methods of providers and consumers of orthodontic treatment.

METHOD

A primary focus is determining the anthropometric bases of self and others' perceived preference and satisfaction with changes in facial appearance. These quantitative analyses have been based on determining the frequency and magnitude of reliability and validity measures of diagnosis, treatment, and satisfaction outcome. Socioeconomic considerations are also quantitated regarding the discrepancy between objective need for treatment as determined for example by the Index of Orthodontic Treatment Need and the subjective demand for treatment.

RESULTS

The major contribution of this article is the quantitation of the components of esthetic experience from sensation of perception using psycho physical methods, such as Perceptometrics, for determining the morphological basis of perceived facial attractiveness adjusted for ethnocultural differences updated by 3-dimensional and artificial intelligence technology. Recent quantitation of smile components has also added to the measures of esthetically successful treatment. Further contribution of orthodontists to mental and physical health is demonstrated by the differences between perceived personality attributes in profile and full-frontal views of symmetric and asymmetric faces. Such information can facilitate the clinician's ability to determine the ideational representation of the patients' perceived pre- and post-treatment outcome.

CONCLUSION

The quantitative analysis of the motives and methods involved in the orthodontic treatment process has been combined with the neurophysiological correlates of producing and observing/evaluation of the esthetic experiences of both patients and orthodontists/dentists.

Aesthetic Parameters and Patient-Perspective Assessment Tools for Maxillary Anterior Single Implants

Background

This review aimed to concisely describe the current aesthetic objective indices for a single-implant maxillary anterior crown. The secondary aim was to propose introducing a unified, standardized questionnaire for adequately collecting patient-reported outcome measures (PROMs) in implant dentistry.

Materials and Methods

A literature review was conducted using both EMBASE/Ovid and MEDLINE/PubMed databases by combining keywords and Emtree/Mesh terms related to “Esthetics,” “Self-Assessment or Surveys and Questionnaires,” and “Single-Tooth Dental Implants.”

Results

The most meaningful aesthetic objective indices for single implants in the literature are the Pink Esthetic Score (PES), the Papilla Presence Index (PPI), Peri‐Implant and Crown Index (PICI), PES/White Esthetic Score (PES/WES), the Implant Crown Aesthetic Index (ICAI), and a modified version of the ICAI (mod-ICAI) index. Clearly, PES/WES is still the most widely accepted tool. It is encouraging to observe that there is an increasing tendency in recent years to report PROMs more frequently in the implant dentistry literature. We proposed the implementation of a unified, standardized questionnaire using a self-administered visual analogue scale (VAS) scoring system, which evaluates overall satisfaction, comfort, tooth appearance, gingival appearance, function, and hygiene complexity. This tool should be validated in the oral implantology research context for its regular implementation or further development.

Conclusions

Conducting qualitative studies among dental implant patients who received few implants or single-tooth implant reconstructions in the aesthetic zone may help dental researchers understand better how to efficiently develop and validate a quantitative instrument. This standard tool would reduce heterogeneity bias by providing comparable data between studies.

Self-perception and self-representation preference between 2-dimensional and 3-dimensional facial reconstructions among dentists, dental students, and laypersons

STATEMENT OF PROBLEM

Computer-aided design (CAD) software can merge the intraoral digital scan with patient photographs or 3-dimensional (3D) facial reconstructions for treatment planning purposes. However, whether an individual perceives a 3D facial reconstruction as a better self-representation compared with a 2-dimensional (2D) photograph is unclear.

PURPOSE

The purpose of this observational study was to compare self-perception ratings and self-representation preference of the 2D and 3D facial reconstructions among laypersons, dental students, and dentists.

MATERIAL AND METHODS

Three populations participated in the study: laypersons, dental students, and dentists (n=20, N=60). Facial and intraoral features were digitized by using facial and intraoral scanners, and a complete-face smile photograph was obtained. Two simulations were performed for each participant: 2D (2D group) and 3D (3D group) reconstructions. In the 2D group, a maxillary digital veneer waxing from the left to the right second premolars was produced without altering the shape, position, or length of the involved teeth. A software program (Dental Systems; 3Shape A/S) was used to merge the maxillary digital waxing with the full-face smile photograph. One image was obtained for each participant. In the 3D group, a dental software program (Matera 2.4; Exocad GmbH) was used to merge the intraoral and facial scans. Subsequently, 1 video of a 180-degree rotation of each 3D superimposition was obtained. Participants evaluated both superimpositions on a scale from 1 (least esthetically pleasing) to 6 (most esthetically pleasing). Finally, participants were asked which superimposition they preferred for a potential treatment outcome representation.

RESULTS

All the ratings were esthetically pleasing (median group rating 5 or 6). When analyzed solely for differences across occupation groups, ratings for the 2D representation varied significantly across populations (Kruskal-Wallis chi-squared=13.241, df=2, P=.001), but the ratings for the 3D representation did not exhibit statistically significant differences (Kruskal-Wallis chi-squared=4.3756, df=2, P=.112). Ordinal logistic regression revealed no significant main effects but a significant effect of the population×image-type interaction on the esthetic rating. All participants felt well-represented in both the 2D and 3D representations. Also, 40% of dentists, 55% of dental students, and 50% of laypersons preferred the 3D reconstructions. Sex and occupation in general had no effect on the ratings. However, students tended to give higher ratings to the 3D representations of themselves.

CONCLUSIONS

There is no evidence based on the current study that 2D and 3D representations were perceived differently, but representation preferences may depend on a person's occupation. When individuals rated 3D visualization higher than 2D visualization, they strongly preferred the 3D visualization for representing the treatment outcome.

Composite resin CAD-CAM restorations for a midline diastema closure: A clinical report

A diastema between the maxillary central incisors affects an esthetic smile and has been treated in various ways. Precise diagnosis is essential to guide the choice of the most appropriate treatment. This clinical report describes closing a maxillary midline diastema with a computer-aided design and computer-aided manufacturing (CAD-CAM) composite resin.

Single versus splinted short implants at sinus augmented sites: A systematic review and meta-analysis

OBJECTIVE

This review primarily evaluated the success, survival and failure rates of implants shorter than 10 mm restored with single-unit or splinted fixed dental prostheses in maxillary sinus augmented sites.

MATERIAL AND METHODS

Two reviewers independently performed the systematic search of electronic databases, including MEDLINE, EMBASE and CENTRAL, up to September 2019 with no language restriction. A supplemental hand search consisted of screening 13 journals. The inclusion criteria were: primary studies reporting implant, prosthetic and patient-reported outcome measures (PROMs) of extra-short and short implants placed in conjunction with sinus floor elevation in partially dentate patients, restored with single- and splinted-crowns for direct comparison, with a minimal 1-year follow-up. Weighted arithmetic mean (WAM) of the implant survival was performed according to the type of prosthesis. This was confirmed by using Review Manager software to perform meta-analysis.

RESULTS

Two observational studies reporting on 106 tapered, press-fit, sintered porous-surfaced implants with a length ranging from 5 mm to 9 mm were included in this systematic review. Of these, 20 and 86 implants were restored with single and splinted prostheses, respectively. The risk ratio (RR) was 1.16 (95% CI: .31-4.30, p = .58, I² = 0%) for individually restored implants failure when compared to splinted implants, indicating that short dental implants restored with single crowns could have a 16% higher possibility of failure if compared to implants with splinted crowns. The heterogeneity value was not statistically significative (p = .58). No statistical difference in the implant survival rate of the two types of analysed prostheses was observed after WAM (p= .923). The level of evidence for the included studies ranged from low (4) to fair (2B).

CONCLUSION

Similar clinical outcomes up to a 9-year follow-up were observed in single and splinted porous-surfaced implants shorter than 10 mm located in sites with sinus lift. However, the conclusion shall be interpreted with caution due to the level of evidence and limited number of included studies included in this systematic review.

An analysis of the aesthetic proportions of anterior maxillary teeth in a UK population

Introduction Many aesthetic proportions have been proposed for use in dentistry: Golden Proportion, Preston's Proportion, Recurrent Esthetic Dental (RED) Proportion and Golden Percentage. Although there have been studies to consider these proportions in other countries, there have been no studies in the UK to evaluate their prevalence and value.Methods The maxillary anterior teeth of 509 students from University of Birmingham's School of Dentistry were photographed in a standardised manner and the aesthetic proportions statistically analysed using an unpaired one-sample t-test.Results Golden Proportion existed in a very limited number of the sample. RED did not exist in the sample. The sample's average ratio was similar to Preston's Proportion; however, there was too wide a distribution for the proportion to be of relevant use. The vast majority of the sample conformed to modified Golden Percentage values; 22.5% for central incisors, 15% for lateral incisors and 12.5% for canines.Conclusion Golden Proportion, Preston's Proportion and RED Proportion have limited value in aesthetic dentistry as they do not accurately or broadly represent natural, aesthetic smiles. However, slightly modified Golden Percentage values are vastly more representative and are recommended as a more relevant geometric component to smile design principles in the UK.

Effects of gingival margin asymmetries on the smile esthetic perception of dental professionals and lay people

OBJECTIVE

To determine the effects of different gingival margin asymmetries of anterior tooth on the smile esthetic perceptions of dentists, prosthodontists, periodontists and lay people.

MATERIALS AND METHODS

A frontal close-up smile photo of a woman was used in this study. Image was digitally altered in order to create gingival margin asymmetries in left maxillary central, lateral incisors, and canines. Four stages of alterations were made in 0.5 mm increments. The final images were randomly assessed by 240 evaluators: 60 dentists, 60 prosthodontists, 60 periodontists, and 60 lay people. Questionnaire was carried out by a single researcher and each rater was asked to evaluate the attractiveness of the smile images by using the visual analog scale. Collected data were analyzed by using one-way ANOVA test with post hoc Scheffé test.

RESULTS

Smiles with 0.5 mm gingival margin asymmetries were found to be more esthetic, while 2 mm gingival asymmetries were less esthetic (P ˂ .001). Lay people's esthetic scores were higher than other groups in all degrees of asymmetries (P ˂ .001). Esthetic scores of canine teeth were higher than, lateral, and central teeth (P ˂ .001).

CONCLUSIONS

As the amount of asymmetries increased, esthetic scores decreased in all groups. Gingival margin asymmetries were less perceptible laterally.

CLINICAL SIGNIFICANCE

This study may help dental professionals to understand which gingival asymmetries are found by patients as esthetic or unesthetic and guides them in their dental treatment, especially in the aesthetic zone.

Tooth Shade Preferences among the General Public

PURPOSE

To identify laypersons' most preferred tooth shade as a function of observer and patient factors, namely patients' skin shade and observers' socio-demographics.

MATERIALS AND METHODS

Two online surveys using computer-designed perioral images with different shades of the skin and teeth were distributed to participants in Montreal (Canada) and San Francisco (USA). The first survey (n = 120) was designed to assess public preferences of tooth shade value, hue and chroma as a function of the skin color of the perioral image (model), and the demographic characteristics of the observer. The first survey included 6 sets of 9 identical perioral images. A different skin shade (from very dark to very light) was used for each set of images, and each set of images presented teeth with different tooth shades which included three different levels of value (2M1, 3M1, 4M1), hue (3L1.5, 3M1, 3R1.5), and chroma (3M1, 3M2, 3M3) of the Vita 3D Master shade guide. Participants were asked to choose their preferred image for each category (value, hue, chroma) within each set of skin shades. A second survey was performed to pinpoint the tooth shade that is preferred the most by the general public. In this survey, images with four tooth shades (1M1, 2M1, 3M1, 4M1) and 6 skin shades were distributed (n = 70). Ordinal logistic regression was used to identify significant predictors of preferred tooth shades.

RESULTS

Most of the participants preferred teeth with the highest value (54%), a neutral hue (59%) and the lowest chroma (89%). About 75% of the participants preferred 1M1 the lightest tooth shade over other shades regardless of their demographics or skin color of the model. Among the observer-related variable, age was the most significant predictor of people preferred tooth shade (p = 0.019).

CONCLUSION

This study showed that there are common preferences in terms of tooth shade value, hue and chroma among participants regardless of demographic variables and facial skin shades. This data could guide dentists for tooth shade selection in the clinical practice.

Layperson and Dental Professional Perception When Evaluating Their Own Virtually 2D or 3D Simulated Esthetic Discrepancies

PURPOSE

To analyze the perceptions of laypersons, dental students, and dentists regarding disparities of the maxillary dental midline and the occlusal plane (OP) when analyzing their own 2D or 3D clinical simulation.

MATERIAL AND METHODS

20 participants per group volunteered (N = 60). Intraoral and facial scans, and a photograph were obtained from each participant. Two simulation groups were created: 2D and 3D groups, which were subdivided into two subgroups. In the first subgroup, the OP was modified by 1-degree increments without changing the maxillary midline. In the second subgroup, the OP was modified by the same increments, but the maxillary midline was altered to match the OP inclination. Participants were asked to rate the simulations on a 1-to-6 scale and a question survey. Ordinal logistic regression (OR) was used to analyze the ratings.

RESULTS

Tilt of the OP had the strongest negative effect on the ratings which was further amplified by the dental midline inclination (OR = 0.122). Midline modification alone did not affect the ratings (OR = 0.744). 3D simulations had a stronger positive effect on the ratings compared to 2D simulations. For dental students, the positive rating effect of 3D simulations was similar to dentists. For laypersons, the positive rating effect of 3D simulations compared to the 2D simulations decreased relative to dentists. The survey revealed that 45% of the dentists, 80% of the students, and 50% of the laypersons preferred the 3D simulation.

CONCLUSIONS

The type of dimensional representation affected the esthetic perception of all participants. 3D simulations obtained higher esthetic ratings for the same esthetic discrepancy than 2D simulations. However, all participants' ratings decreased with increased tilt of the OP and were further decreased with the inclination of the dental midline.

Aesthetic aspects of adjacent maxillary single-crown implants-influence of zirconia and titanium as implant materials

The purpose of this retrospective survey was to assess the esthetic aspects of adjacent zirconia and titanium implants in the anterior maxillary area. A total of 40 patients and 109 adjacent implants (17 patients with 47 titanium implants and 23 patients with 62 zirconia implants) was included. The primary aim of this survey was to assess the papillary fill (Jemt score). Additionally, further esthetic aspects were assessed. Papillae were fully present (Jemt score 3) around 39.1% of adjacent zirconia implants and 17.4% of adjacent titanium implants (p<0.01). The papilla deficit was significantly higher 1.64 mm (SD 1.35) around titanium compared to zirconia implants 0.92 mm (SD 0.94, p<0.01). The evaluation of the soft tissue recessions revealed no differences between implant materials, whereas titanium implants presented more visible implant shadows (p<0.01). Zirconia implants had more implants with papillae that filled the entire proximal space compared to titanium implants. Furthermore, titanium implants had a greater frequency of visible implant shadowing than the zirconia implants. Esthetic rules such as the interdental contact area and golden percentage rules did not differ significantly between the titanium and zirconia implants.

Evaluation of the maxillary midline, curve of the upper lip, smile line and tooth shape: a prospective study of 140 Caucasian patients

Background

A number of reference patterns such as the interincisal line, curve of the upper lip, width of the smile or shape of the teeth have been studied in different populations. Determining the frequency of different smile aesthetic parameters in a European Caucasian population and exploring possible gender differences is important in order to obtain predictable treatment outcomes.

Methods

Photographs were obtained under resting and forced smiling conditions in 140 individuals (70 males and 70 females) with a mean age of 20.1 ± 4.3 years. Different variables were recorded, including the position of the maxillary interincisal midline in relation to the facial midline, the arc and width of the smile, and the shape of the teeth. The data were processed using the SPSS version 15.0 statistical package, with application of the chi-squared test and a confidence level of 95%. The statistical power was 80%, and the level of significance 5% (α = 0.05).

Results

A total of 94.3% of the sample presented a maxillary interincisal midline coinciding with the facial midline, and 80% had a consonant smile line. The curve of the upper lip was upwards in 47.1% of the cases, followed by a straight curve in 41.4%. Most of the subjects (84.3%) presented a medium smile line with tooth exposure to the second premolar (61.4%). There were no significant differences between males and females.

Conclusions

The integration of aesthetic criteria is needed in order to guarantee satisfactory and predictable dental treatment outcomes. There were no statistically significant differences between males and females. The maxillary interincisal midline coincided with the facial midline, with a consonant smile arc and a medium smile line, upward lip curve and oval tooth shape.

Esthetic dental perception comparisons between 2D- and 3D-simulated dental discrepancies

STATEMENT OF PROBLEM

Intraoral scanners (IOSs), facial scanners (FSs), and computer-aided design (CAD) software programs have become powerful tools for treatment planning. However, discrepancies in perception regarding 2-dimensional (2D) or 3-dimensional (3D) simulations by dentists, dental students, and laypeople have not been analyzed.

PURPOSE

The purpose of this observational study was to analyze the perceptions of laypersons, dental students, and dentists regarding disparities of the maxillary dental midline and the occlusal plane when analyzing the dental discrepancies on 2D- and 3D-clinical simulations.

MATERIAL AND METHODS

A female model was digitized by using an FS, IOS, and a full-face smile photograph. Dental discrepancies were simulated by using a 2D photograph (2D group) and 3D scan (3D group) of the model. In both simulation groups, 2 subgroups were produced. The occlusal plane of the first subgroup was modified in 1-degree increments without changing the dental midline or the position of the maxillary dental incisors. In the second subgroup, the occlusal plane was modified by using the same increments, but the maxillary central incisors and dental midline were altered to match the inclination of the occlusal plane. A total of 300 participants (N=300) were asked to rate the 2D images (N=12) and 3D videos (N=12) on a 1-to-6 scale and answer a questionnaire. Ordinal logistic regression was used to analyze the ratings.

RESULTS

The ratings decreased with the increased tilt of the occlusal plane, and the layperson group gave consistently higher ratings than the other 2 groups. For dentists, the odds of giving a higher versus lower rating decreased by almost a half for each degree of tilt. However, for students, that effect was diminished by a positive interaction term, and for laypersons, the effect was even less. Students gave similar ratings to dentists, but laypersons gave higher ratings. As the age of the participants increased, however, the ratings also increased. The use of 3D versus 2D images had a positive effect on the ratings, but the effect decreased for the student observers and decreased even further for laypersons. Furthermore, midline alteration led to higher ratings but also resulted in worsening of the odds ratio for the tilt. Seventy percent of the dentists, 57% of the dental students, and 52% of the laypersons preferred 2D simulations to 3D simulations.

CONCLUSIONS

Dentists, dental students, and laypersons decreased their ratings with increased inclination of the occlusal plane; however, laypersons still graded all the 2D and 3D images as esthetically pleasant, giving consistently higher ratings than the dentists and dental students. Overall, 3D simulations obtained higher ratings than 2D images, but the positive effect decreased for the student observers and decreased even further for laypersons.

Comparison of smile esthetics among celebrities, dentists, and dental students in a Han Chinese population

STATEMENT OF PROBLEM

Various components of smile esthetics have been evaluated. However, whether these components affect smile esthetics in Han Chinese celebrities, dentists, and dental students is unknown.

PURPOSE

The purpose of this study was to evaluate the smile esthetics of celebrities, dentists, and dental students in a Han Chinese population.

MATERIAL AND METHODS

Frontal images of smiles were obtained from the Internet for the celebrity group, while images of dentists and dental students were collected for the dentist and dental student groups. The buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, the number of teeth revealed, the width ratio relative to the golden proportion, and the width-to-length ratios of maxillary anterior teeth were calculated by using a photo-editing software program. Statistical analysis was performed by using 2-way ANOVA and the Tukey HSD test (α=.05).

RESULTS

Eligible images were obtained for 81 celebrities, 83 dentists, and 78 dental students. The celebrities were found to have the highest buccal and posterior corridor ratios and reveal the least teeth in the smile among the 3 groups (all P<.001). The alignment discrepancy for celebrities was significantly less than that for dental students (P=.025). Moreover, the absolute difference of width ratios from the golden proportion was significantly different from 0 for all groups (all P<.001).

CONCLUSIONS

Significant differences were found in the smiles of Han Chinese celebrities, dentists, and dental students in regard to the buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, and the number of teeth revealed. Chinese celebrities tended to have a smile that displays to the second premolar, with a medium buccal corridor width.

Evolution of Aesthetic Dentistry

One of the main goals of dental treatment is to mimic teeth and design smiles in a most natural and aesthetic manner, based on the individual and specific needs of the patient. Possibilities to reach that goal have significantly improved over the last decade through new and specific treatment modalities, steadily enhanced and more aesthetic dental materials, and novel techniques and technologies. This article gives an overview of the evolution of aesthetic dentistry over the past 100 y from a historical point of view and highlights advances in the development of dental research and clinical interventions that have contributed the science and art of aesthetic dentistry. Among the most noteworthy advancements over the past decade are the establishment of universal aesthetic rules and guidelines based on the assessment of natural aesthetic parameters, anatomy, and physiognomy; the development of tooth whitening and advanced restorative as well as prosthetic materials and techniques, supported by the pioneering discovery of dental adhesion; the significant progress in orthodontics and periodontal as well as oral and maxillofacial surgery; and, most recently, the implementation of digital technologies in the 3-dimensional planning and realization of truly natural, individual, and aesthetic smiles. In the future, artificial intelligence and machine learning will likely lead to automation of aesthetic evaluation, smile design, and treatment-planning processes.

Clinical performance of zirconia implants: A meta-review

STATEMENT OF PROBLEM

The clinical effectiveness of zirconia implants as an alternative to titanium implants is still controversial.

PURPOSE

The purpose of this analysis was to identify and evaluate systematic reviews reporting on the clinical outcomes of zirconia implants for oral rehabilitation.

MATERIAL AND METHODS

An electronic search was undertaken on MEDLINE, Embase, and the Cochrane Oral Health Reviews databases up to December 24, 2018, without language restriction. Eligible reviews were screened and assessed. The eligibility criteria were systematic reviews or meta-analyses, implant survival rate, implant success, marginal bone loss, peri-implant soft tissue status, and biologic and functional complications of zirconia implants. Two review authors independently evaluated the quality assessment of the secondary studies by applying the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) tool.

RESULTS

Nine reviews fulfilled the inclusion criteria and were evaluated. Seven reviews were classified as moderate and 2 as high quality. The overall AMSTAR's quality of these reports was moderate. In the primary studies contained in these reviews, zirconia implant clinical outcomes were found to be similar or inferior to those for titanium implants. The few primary clinical studies contained in these reviews were not homogeneous among each other, presented poor methodology, and only offered promising short-term outcomes due to the lack of long-term follow-ups.

CONCLUSIONS

Based on this meta-review, in spite of short-term promising results of zirconia implants, evidence with long term is lacking.

Systematic review versus structured critical analysis

Objective: This analysis discusses common problems with systematic reviews (SRs) and presents a novel solution, the structured critical analysis (SCA) that can be incorporated into a SR or used as an alternative literature review design.Methods: A cross-sectional survey of current SRs related to interdisciplinary restorative dentistry was obtained by evaluating 100 current SRs for their self-reported methodological quality and its effect on scientific validity.Results: The preferred reporting items for systematic reviews and meta-analyses protocol (PRISMA) was used in 99/100 SRs, but only 8/100 reported a low risk of bias. High statistical heterogeneity precluding meta-analysis was found in 44/100 SRs. Only 94 paragraphs/100 SRs provided critical analysis.Discussion: Significant problems were found with current SRs that can compromise their reliability as the premier level of evidence for clinical science research. The reader must be aware of these deficiencies to correctly interpret the SR and cannot rely on the format alone.

The treatment dilemma of missing maxillary lateral incisors-Part II: Implant restoration

OBJECTIVE

This second of a two-part series reviews the single dental implant as the most current treatment alternative for replacement of a missing or lost maxillary lateral incisor. Assessments of dental maturity for implant placement, implant space requirements, surgical and restorative influence on soft tissue profiles, and implant success are reviewed.

OVERVIEW

Recent data indicates that implant success rates are high, and esthetics and soft tissue profiles appear to be stable for maxillary lateral incisor implants. Implant placement should be assessed by dental maturity of the specific patient as opposed to chronological age, and implant spacing should be developed and assessed by all team members.

CONCLUSIONS

Implant replacement of a missing lateral incisor is a predictable treatment mode if implant placement is deferred until dental maturity and then accurately placed in a well-developed site. Treatment involves more complicated planning and execution from team members than other alternatives, but innovations in techniques and materials render it a favorable alternative for lateral incisor replacement.

CLINICAL SIGNIFICANCE

Implant restoration of a missing or lost maxillary lateral incisor is surgically and restoratively more complex than space closure or a resin-bonded fixed dental prosthesis but demonstrates high success rates and high esthetic potential when team members follow strict treatment protocols.

Perception of occlusal plane that is nonparallel to interpupillary and commissural lines but with the maxillary dental midline ideally positioned

STATEMENT OF PROBLEM

How disparities in parallelism between the occlusal plane and the interpupillary (IP) or commissural facial front lines are perceived is unclear.

PURPOSE

The purpose of this observational study was to examine the perceptions of laypersons, dental students, and dentists regarding disparities of the anterior occlusal plane (AOP) and posterior occlusal plane (POP) with respect to the IP and commissural line (CL) with the maxillary dental midline ideally positioned.

MATERIAL AND METHODS

A model of a symmetric female face was digitally created with the IP and CL parallel and the facial midline coincident with the maxillary dental midline. Two groups of images were created, one with the POP modified in 1-degree increments, in which both the maxillary dental midline and the position of the maxillary central incisors were not manipulated, and the other with the POP modified in the same increments but with the position of both maxillary central incisors lengthened to follow the inclination of the occlusal plane. Participants (N=312) were asked to rate the images on a 1-to-6 scale. The Kruskal-Wallis medians test and ordinal logistic regression were used to analyze the ratings.

RESULTS

Group median ratings for different occupations gradually decreased with increased inclination of the occlusal plane. Significant differences were found for inclinations from 2 to 5 degrees. Significant odd ratios were found for age and sex.

CONCLUSIONS

Dental professionals detected smaller POP disparities. The dentist and dental student groups gave lower ratings in proportion to the amount of POP inclination. Laypersons gave lower ratings only after 3 degrees of POP inclination but still graded all the images as esthetically pleasant. Older people and men tended to give higher ratings to the same image.