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21.
ObjectivesTo compare the effect of various degrees of decalcification after orthodontic treatment (white spot lesions) on orthodontists'', general dentists'', and laypersons'' ratings of smile esthetics.Materials and MethodsEight photographs representing incrementally altered tooth decalcification lesions of maxillary anterior teeth ranging from mild to severe were shown randomly to the study participants. Photographs were rated by a matched sample of orthodontists (N = 42), general dentists (N = 52), and laypeople (N = 58). A visual analogue scale (VAS) was used to assess perceptions of smile esthetics.ResultsThe three groups of raters could distinguish between different decalcification levels. Raters gave more negative scores as the decalcification level increased.ConclusionsThe three groups of raters were able to distinguish between various degrees of decalcification lesions. General dentists were the most critical of all groups when rating decalcification lesions.  相似文献   
22.
Objectives:To provide an empirical test of the applicability of Locker''s conceptual model of oral health for malocclusion patients, and to suggest alternative models of the effect of malocclusion on well-being.Materials and Methods:Data from a survey of 323 adolescents attending for orthodontic treatment were analyzed to develop a new oral health model for malocclusion patients. Oral health–related quality of life (OHRQoL) was measured using the 14-item Oral Health Impact Profile; malocclusion was measured using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN). Using structural equation modeling, the relationship between conceptual domains in Locker''s model was explored and three models of their interrelationship tested for goodness of fit.Results:Fit indexes for Locker''s model indicated that it did not fit the data well. Therefore, a modified model was developed to incorporate additional paths between other levels to better fit the data. The best fit was provided by a model in which the direct effects of malocclusion on pain, discomfort, and handicapping—and the direct effect of pain on disability—were removed. A direct effect of functional limitation on disability was allowed. The modified Oral Health Impact Profile model proved to be a good fit to the data (root mean square error of approximation  =  0.069).Conclusion:The pathways identified in Locker''s (1988) conceptual model of oral health may not be appropriate for describing the relationships between OHRQoL constructs in individuals with malocclusion. An alternative model is proposed.  相似文献   
23.
Objective:To correlate the objective cephalometric measurements with subjective facial esthetics in patients with bimaxillary protrusion.Materials and Methods:The sample consisted of 60 Asian-Chinese patients with bimaxillary protrusion who met the inclusion criteria. The facial esthetics of posttreatment profile and the change of profile on standardized lateral photographs were rated by a panel of 10 orthodontists and a panel of 10 lay persons with bimaxillary protrusion. All of the pretreatment and posttreatment cephalograms were digitized and traced. Twenty-five cephalometric measurements were constructed and analyzed. Correlations between the subjective facial esthetic scores and each cephalometric measurement were evaluated.Results:The cephalometric measurements correlated with the facial esthetic scores of posttreatment profile given by the orthodontist and the lay persons were basically the same. For the evaluation of posttreatment profile in bimaxillary protrusion patients, the upper and lower lip to E-line, upper and lower incisor tip to AP plane, Pg-NB distance, mentolabial angle, and sulcus depth correlated significantly with the esthetic score. For the evaluation of profile change during orthodontic treatment, retraction of upper incisor relative to AP plane or the perpendicular line through sella (line Y), change of upper incisor inclination, change of mentolabial sulcus depth, and retraction of lips relative to E-line were correlated positively with the esthetic value.Conclusions:Cephalometric measurements of lip position, incisor position, and chin morphology were key parameters correlated to facial esthetics.  相似文献   
24.

Purpose:

The purpose was to examine the existence of divine proportions among the Indian faces in Moradabad population.

Materials and Methods:

Totally, 100 patients (50 males; 50 females) aged 25-45 years were selected for the study. All facial photographs were analyzed based on the method of Ricketts assessing the divine proportions in vertical and transverse facial planes. Six horizontal and seven vertical ratios were determined, which were then compared with the phi ratio.

Results:

The horizontal ratio results showed that three male and female ratios were not significantly different from each other (P > 0.05), and interchilion/nose width ratio was highly significant (P < 0.001). The horizontal mean ratios for females as well as males were highly significant from the phi ratio (P < 0.001) except for interchilion/interdacryon ratio, which was significant (P < 0.05) for females and not significant (P > 0.05) for males. The vertical ratio results showed that there was a highly significant difference (P < 0.001) for forehead height/stomion-soft menton ratio and no significant difference for two ratios between the mean ratios of males and females. All the vertical mean ratios for both the groups were highly significant (P < 0.001), except for the intereye-soft menton/intereye-stomion ratio, which was significant (P < 0.05) for female group and not significant (P > 0.05) for the male group.

Conclusion:

Although, the golden proportion is a prominent and recurring theme in esthetics, it should not be embraced as the only method by which human beauty is measured to the exclusion of others factors.  相似文献   
25.
??Objective    To evaluate the aesthetic outcome of early single-tooth implant in the anterior maxilla. Methods      Thirty patients with single-tooth lost were treated with early implant surgery. The outcome was assessed after the final restoration was completed 2 days??3 months??12 months and 24 months later. The bone resorption??pink esthetic score??PES????modification sulcus bleeding index??MBI????probing depth??PD??and patient satisfaction were observed to evaluate the aesthetic effect and survival rate. Results    The implant survival rate was 100%. Bone resorption were??0.61 ± 0.16??mm. Significant improvement of PES was found between baseline and 2-year assessment. The MBI score was??0.98 ± 0.68??mm on average. The PD score was??2.16 ± 0.27??mm on average. The score between MBI and PD showed no significant difference at every testing time. The extreme satisfaction was 86.6%. Conclusion    Single-tooth lost in esthetic zone may-be performed early implant which can acquire a satisfactory aesthetic  effect.  相似文献   
26.
This case shows an excellent esthetic treatment outcome using implant‐retained crowns replacing maxillary laterals and canines in hypodontia patient with unusual incidence of spontaneous diastema closure after the placement of implants. To our knowledge, this is the first case report showing maxillary midline diastema closure after implant placement.  相似文献   
27.
Hypohydrotic ectodermal dysplasia is a hereditary disorder, which affects ectodermal derivatives. It manifests several abnormalities of the teeth, and is commonly inherited through female carriers. This case report presents a patient with compromised esthetics and function. A multidisciplinary approach was planned involving an oral pathologist, endodontist, orthodontist and a prosthodontist.  相似文献   
28.
目的:评价120例中国成年人相邻上前牙的宽度比和上前牙临床冠的宽长比,为口腔美学诊疗提供依据。方法:分别在华北、东南、西南地区三家口腔医院的义齿加工中心按照纳入和排除标准收集上颌石膏模型,拍摄标准数码照片,以ImageJ软件测量相邻上前牙的宽度比和上前牙临床冠的宽长比,评价相邻上前牙的宽度比与黄金分割比例和Preston比例有无差异,上前牙临床冠的宽长比与理想值0.80有无差异,分析不同性别、左右两侧和不同地域中国成年人的上前牙美学比例有无差异。结果:侧切牙与中切牙的宽度比为0.724±0.047,尖牙与侧切牙的宽度比为0.814±0.092;中切牙、侧切牙和尖牙的临床冠宽长比分别为0.848±0.072、0.834±0.094、0.883±0.098;上述比例与既往理想值的差异均有统计学意义(P<0.001)。不同性别、左右两侧和不同地域进行比较,侧切牙与中切牙的宽度比:右侧比左侧大(分别为0.730±0.044和0.718±0.050)、华北地区比西南地区小(分别为0.711±0.051和0.731±0.044);中切牙的临床冠宽长比:女性比男性大(分别为0.855±0.074和0.835±0.068)、右侧比左侧大(分别为0.855±0.073和0.842±0.072);侧切牙的临床冠宽长比:女性比男性大(分别为0.843±0.097和0.817±0.084);上述差异均有统计学意义(P<0.05)。结论:中国成年人上前牙美学比例具有自身特点,应用时需考虑性别和地域差异。  相似文献   
29.
目的:探讨正畸患者对不同程度上颌牙列中线轴向倾斜的审美评价。方法:采用上颌牙列中线不同程度轴向倾斜的图片模型,制作电子问卷软件,对203位符合条件的正畸患者(男79人,女124人)分理想值、觉察值和容忍值3个层次进行问卷调查。结果:受试对象对女性图片上颌牙列中线轴向向左、右倾斜的平均觉察值分别是4.7°、4.9°,容忍值是9.7°、9.5°;男性图片则为4.1°、5.1°和9.0°、9.7°。其中除了男性图片左、右侧的觉察值之间有统计学差异之外(P<0.05),其余评价值左、右侧之间无统计学差异(P>0.05)。觉察值的中位数和四分位数间距均为4.0°,2.0°;容忍值则均为10.0°,6.0°。女性和男性图片平均理想值分别为0.1°和0.4°,且与总体均数μ=0间无统计学差异(P>0.05)。女性受试者对男性图片牙列中线右侧轴向倾斜的觉察值要明显低于男性受试者。结论:该审美评价的3个层次是合理的,其研究结果对口腔科医生具有临床指导意义。  相似文献   
30.
Purpose: Successful replacement of posterior teeth using contemporary prosthodontic techniques in esthetically demanding cases relies upon visual replication of the natural posterior dentition and surrounding gingival architecture. There is currently little in the way of guidance for creating ideal or acceptable gingival relationships for posterior teeth. Materials and Methods: A cross‐sectional study was conducted comparing perceptions of four groups of individuals to six digitally manipulated images with various posterior teeth gingival margin position configurations. A total of 120 volunteers aged 12 years to 80 years, comprising 30 patients diagnosed with hypodontia, 30 patients diagnosed with periodontal disease, 30 patients without either condition, and 30 qualified dentists were recruited from the Eastman Dental Institute & Hospital, London. A ranked order of preference for each set was obtained, and this was repeated after a minimum time interval of 10 minutes. Results: Posterior gingival margin configurations from 0 mm to 2 mm (measured at the first premolar) were deemed most esthetic by the majority of the patient groups; dentists had a strong preference for the 1 mm configuration. Dentists appeared to be more perceptive to the alterations in gingival positions. Conclusions: Posterior gingival margin configurations where the first premolar margins were 1 mm lower than the canine margins were deemed the most esthetically pleasing; however, it is likely that a range of acceptability of 1 mm deviations from this ideal exists.  相似文献   
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