Pathological tooth migration-spontaneous correction of diastema after surgical periodontal therapy: a case report.

A common consequence of moderate to extreme periodontitis is pathologic migration. This denotes tooth movement when the periodontal disease interjects the equilibrium among the elements that preserve physiological tooth position. The balancing factors can migrate the teeth in any direction. The etiology of pathological migration tends to be multifactorial, thus achieving early diagnosis is imperative, which will ultimately lead to the prompt removal of the etiological factors while avoiding severe bone destruction. In this case maxillary central incisors had diastema due to pathological migration with mobility grade I in maxillary left central incisor. Many cases of moderate to severe pathological migration need a suitable, interdisciplinary approach. Nevertheless, since it is possible to detect mild cases of Pathological tooth migration (PTM) at an early stage, spontaneous correction of migrated teeth can be accomplished by periodontal therapy alone. Regardless of the treatment selected, maintenance of stable results should be considered as an aim of treatment.

Diastema: precisando terminologia anatomica / Diastema: specifying terminologia anatomica

RESUMEN: Diastema es un término latino de origen griego incorporado a Terminologia Anatomica bajo el código A05.1.03.078. Odontológicamente, es un espacio interdentario ubicado entre dientes adyacentes del arco dental, siendo su presencia considerada normal en el periodo de dentición mixta. Fueron consultados diccionarios de los idiomas español, griego y latín, de términos médicos y etimológicos, en búsqueda de las apariciones iniciales del término diastema y sus posteriores usos en la historia. La búsqueda reportó que Diastema ha sido utilizado para indicar una distancia o intervalo, referido a lugares, tiempos e incluso entre tonos musicales. En el área de las ciencias médicas, es un término que ha señalado la separación entre los dedos o el espacio virtual creado por la insuflación de los pulmones, siendo su mayor acercamiento a la morfología en el área veterinaria para designar el espacio que separa los dientes anteriores de posteriores, especialmente en roedores y rumiantes. Para ser consistentes con los lineamentos actuales de la Federative International Programme for Anatomical Terminology y los acuerdos terminológicos de los Simposios Ibero-Latinoamericanos de Terminologia Anatomica, Histologica y Embryologica, sugerimos el reemplazo del término Diastema por Spatium interdentale, como un avance en la precisión y descripción de la estructura incorporada a Terminologia Anatomica.

SUMMARY: Diastema is a latin term of greek origin incorporated into Terminologia Anatomica under the code A05.1.03.078. Odontologically, it is an interdental space located between teeth adjacent to the dental arch, its presence being normal in the period of mixed dentition. Dictionaries of the Spanish, Greek and Latin languages, of medical and etymological terms were consulted, in search of the initial occurrences of the term Diastema and its subsequent uses in history. The search reported that Diastema has been used to indicate a distance or interval, referring to places, times and even between musical tones. In the area of medical sciences, it is a term that has indicated the separation between the fingers or the virtual space created by insufflation of the lungs, being its closest approach to morphology in the veterinary area to designate the space that separates the incisors and molars tooth, especially in rodents and ruminants. To be consistent with the current guidelines of the International Federative Program of Anatomical Terminology and the terminological agreements of the Ibero-Latin American Symposia of Anatomical, Histological and Embryological Terminology, we suggest the replacement of the Diastema period with Spatium interdentale, as an advance in accuracy and description of the structure incorporated into Terminologia Anatomica.

Occlusal traits, orthodontic treatment need and treatment complexity among untreated 17-21-year-olds in Estonia.

Objective: To analyze data on occlusal traits, orthodontic treatment need and treatment complexity in orthodontically untreated 17-21-year-old Estonians.Materials and methods: Clinical records and plaster casts of 390 untreated young adults (219 females and 171 males, mean age 18.5 years, range 17-21 years) were analyzed. Assessed occlusal traits included first molar and canine sagittal relationship, overjet, overbite, crowding, midline diastema, crossbite and scissor bite. The Index of Complexity, Outcome and Need (ICON) was used to assess orthodontic treatment need and complexity. Participants' opinions regarding their teeth were determined with a questionnaire.Results: The most prevalent occlusal traits were Class I sagittal relationship in canines (76%) and molars (70%), crowding (51%), overbite ≥3.5 mm (48%), the end-to-end sagittal relationship in canines (48%) and overjet ≥3.5 mm (47%). Antero-posterior asymmetry was common both in canines (39%) and molars (37%). According to ICON, 36% of participants had orthodontic treatment need.Conclusions: Desire for orthodontic treatment was associated with crowding and increased overjet, and with no gender difference, participants' main expectation of treatment was an improvement in dentofacial aesthetics. Treatment needs determined with ICON was moderate and in line with the participants' desire for orthodontic treatment.

Maxillary labial frenum morphology and midline diastema among 3 to 12-year-old schoolgoing children in Sri Ganganagar city: A cross-sectional study.

INTRODUCTION: Dentofacial aesthetics plays an important role in social interaction and psychological well-being because it affects how people perceive themselves and how they are perceived by society. The maxillary labial frenum is a fold of tissue, usually triangular in shape, extending from the maxillary midline area of the gingiva into the vestibule and mid portion of the upper lip. Maxillary anterior spacing or diastema is a common aesthetic complaint of patients and is frequently seen in children especially in the mixed dentition stage. AIMS AND OBJECTIVES: 1. To estimate the prevalence of different morphologic types of maxillary labial frenum among children of age 3 - 12 years. 2. To find out the relationship between the level of insertion of the frenum and age of the child.3. To evaluate the correlation between frenum morphology, insertion and midline diastema in children. MATERIALS AND METHODOLOGY: The direct visual method under natural light was used and the upper lip was lifted with the index finger and thumb of both hands which allowed for the observation and classification of the labial frenum morphology according to Sewerin's typology and its attachment according to Placek et al. The midline diastema was determined by measuring the distance between the midpoints of the mesial surfaces of both central incisors with the help of divider and ruler. The values were recorded in the prepared schedule. SUMMARY AND CONCLUSIONS: The presence of an abnormal frenum can be a cause in persistent midline diastemas. Tooth movement usually is deferred until eruption of the permanent canines but can begin early in certain cases with very large diastemas.

Influence of tooth position on wind instrumentalists' performance and embouchure comfort : A systematic review.

PURPOSE: To systematically search the scientific literature concerning the influence of tooth position on wind instrumentalists' performance and embouchure comfort. METHODS: The PubMed, Cochrane, and Embase databases were searched up to November 2017. The main orthodontic journals were searched for papers older than the inception date of PubMed. Grey literature was sought via Google Scholar. Eligible studies were critically appraised and analysed. RESULTS: The searches retrieved 54 papers. Only two met the inclusion criteria. Searching the orthodontic journals and Google Scholar resulted in two additional eligible studies. All four studies had a cross-sectional design. The sample sizes ranged from 20-100 participants, varying from children to professional musicians. Because of a large heterogeneity in outcome variables, no meta-analysis could be performed. Descriptive analysis shows that there are indications that tooth irregularities have a negative influence on embouchure comfort and performance of a wind instrument player. A large overjet may impede the embouchure of brass musicians and may have a negative influence on trumpet player performance. A wide jaw form seems more beneficial to trumpet player performance than a small jaw form. Furthermore, players of all types of wind instruments can experience embouchure difficulties from extreme spacing or an open bite. CONCLUSION: Tooth position can influence musical performance and embouchure comfort of wind instrumentalists. A Class I relationship without malocclusion seems appropriate for every type of wind instrument. The more extreme the malocclusion, the greater the interference with wind instrumentalists' performance and embouchure comfort. Evidence however is limited.

Width of dental arches in patients with maxillary midline diastema.

BACKGROUND: The aims of the study were as follows: (1) to examine the width of the dental arches of patients with maxillary midline diastema and compare it with control group; (2) to investigate the impact of the width of upper dental arch on the width of diastema. MATERIALS AND METHODS: Diagnostic orthodontic plaster models of 102 patients with permanent dentition were studied. Patients were divided into two groups: study group with diastema and control group without diastema. Patients with severe malocclusion, craniofacial diseases, hypodontia and microdontia and pa-tients with periodontal disease were excluded. The transpalatal width of palate, premolar and molar arch widths in Pont's points of upper and lower jaw were measured using digital calliper. The results were statistically analysed. RESULTS: Analysis showed a significant correlation between presence of diastema and premolar and molar width of the dental arches for both upper and lower jaw. Studied widths were larger in patients with diastema compared to the group without diastema. Analysis of the transpalatal width showed statistically significant differences between the study group and the control group. Analysis of widths of diastema and transpalatal widths showed that there was not statistically sig-nificant correlation. CONCLUSIONS: Patients with diastema had increased in size in both the premolar and molar width of the dental arches. Increase the width affect to both upper and lower dental arch. Patients with diastema also were characterised by often occurrence of normal or increased of the transpalatal width but the width of the diastema did not correlate with the width of the palate. (Folia Morphol 2018; 77, 2: 340-344).

Wooly hair nevus.

Woolly hair nevus is a rare condition characterized by a structural anomaly of the hair, restricted to certain areas of the scalp. The hair becomes coiled and slightly hypopigmented. The term woolly hair refers to changes that affect all the scalp and has a hereditary character. We present a case of woolly hair nevus, that developed at the age of 2 years, associated with dental diastema and verrucous epidermal nevus.

Morphological variations of median maxillary labial frenum: A clinical study.

BACKGROUND: Median maxillary labial frenum (MMLF) appears as a fold of mucous membrane extending from the lining of the mucous membrane of the lips towards the crest of the alveolar ridge on the labial surface. MMLF can demonstrate certain variations in their shape, size and position, both among individuals and within the same individual at different ages. Many clinicians, not being aware of the normal variations of median maxillary labial frenum misinterpret them as pathological entities. OBJECTIVES: The objectives of the study were to determine the prevalence of morphologic variations of MMLF, to classify the morphological variations of MMLF on the basis of their location on the frenum and to compare the morphological variations of MMLF among different age groups and genders. MATERIALS AND METHODS: The study was conducted on 700 males and 700 females of age 5 to 74 yrs, chosen randomly. They were equally divided on the basis of age into 7 groups, each group having equal gender distribution. The morphological variations of MMLF were classified according to Sewerin's classification and the attachments on the freni were further sub-classified. RESULTS: The commonest type of frenum was found to be the simple type, whereas bifid frenum was not found at all. Statistically significant difference was found in proportion of types of frenum among the different age groups and also in proportion of types of frenum among the different sites of presence of frenal attachments. No statistically significant difference was found in proportion of types of frenum in male and female subjects. CONCLUSION: This study shows that MMLF presents with an array of morphological variations. These morphological variations may sometimes pose a complicating factor in maintaining oral hygiene, speech, mastication, esthetics, denture construction, etc. Hence, appropriate recognition of frenal variations and subsequent modification of treatment procedures are essential for a successful outcome of therapy.

Stature Estimate by the Upper Arch: Carrea´s Method Modified / Estimación de la Estatura por Medio del Arco Superior: Método de Carrea Modificado

The Carrea's index is an alternative to estimate the human stature. However, in cases when the jaw is affected, this technique becomes impracticable. Expanding the use of the Carrea's index, by extending it to the upper elements, would increase the chances of the method, especially in cases when only the skull is available for analysis. The aim of the study was to test a new denominator for Carrea's index, so that it could be used for the upper arch, aiming at a new feature to estimate human stature. Plaster models of the arch and the string of the upper arch of 107 dentistry students, aged between 18 and 30 years, previously submitted to anthropometric analysis, were measured with a digital caliper. The data found were inserted in software developed to find a denominator that would result in a higher number of correct answers to real statures, evaluating the left and the right hemiarch, and their average. For the right hemiarch, the denominator with more accuracy for the real stature was the interval from 2.573 to 2.583, with 58.9 %. For the left hemiarch, the best values were from 2.553 to 2.554 with 63.6 %. The average of hemiarchs had as ideal denominator values between 2.579 and 2.581, with 60.7 %. We found no significant statistical difference between denominators. It was possible to obtain a new denominator to apply Carrea's index for the upper arch. The new method had satisfactory accuracy rate and should be tested in other populations to verify its applicability.

El índice de Carrea constituye una alternativa para la estimación de la estatura humana. Sin embargo, esta técnica se torna inviable cuando la mandíbula se encuentra comprometida. Su aplicación a partir de elementos dentales superiores, resultaría de utilidad en los casos en que sólo se dispusiese del cráneo para examinar. El objetivo del estudio fue proponer un nuevo denominador para que el índice de Carrea pueda ser utilizado para el arco superior, en la búsqueda de otro recurso para estimar la estatura humana. El arco y la cuerda fueron medidos, con un calibre digital, sobre los respectivos modelos de yeso superiores de 107 estudiantes de Odontología, que tenían entre 18 y 30 años de edad y habían sido sometidos a análisis antropométricos previos. Los datos obtenidos fueron analizados matemáticamente mediante un programa desarrollado para encontrar un denominador, que proporcionase un mayor número de aciertos para las estaturas reales, evaluando el hemiarco derecho, izquierdo y la media de los hemiarcos. Para el hemiarco derecho, el denominador más apropiado para la estatura real correspondió al intervalo 2,573-2,583, con 58,9 % de acierto. Para el hemiarco izquierdo, los mejores valores quedaron comprendidos entre 2,553 y 2,554, con 63,6 % de acierto. La media de los hemiarcos determinó guarismos ideales, oscilantes entre 2,579 y 2,581, con 60,7 % de acierto. No hubo diferencia estadísticamente significativa entre los denominadores hallados. Se obtuvo un nuevo denominador, que permitió el empleo del índice de Carrea para el arco superior, con una tasa de acierto satisfactoria. No obstante, este método debe ser probado y validado para otras poblaciones, verificando su aplicabilidad.

Wooly hair nevus

Abstract Woolly hair nevus is a rare condition characterized by a structural anomaly of the hair, restricted to certain areas of the scalp. The hair becomes coiled and slightly hypopigmented. The term woolly hair refers to changes that affect all the scalp and has a hereditary character. We present a case of woolly hair nevus, that developed at the age of 2 years, associated with dental diastema and verrucous epidermal nevus.

The Smile Esthetic Index (SEI): A method to measure the esthetics of the smile. An intra-rater and inter-rater agreement study.

PURPOSE: To propose a method to measure the esthetics of the smile and to report its validation by means of an intra-rater and inter-rater agreement analysis. MATERIALS AND METHODS: Ten variables were chosen as determinants for the esthetics of a smile: smile line and facial midline, tooth alignment, tooth deformity, tooth dischromy, gingival dischromy, gingival recession, gingival excess, gingival scars and diastema/missing papillae. One examiner consecutively selected seventy smile pictures, which were in the frontal view. Ten examiners, with different levels of clinical experience and specialties, applied the proposed assessment method twice on the selected pictures, independently and blindly. Intraclass correlation coefficient (ICC) and Fleiss' kappa) statistics were performed to analyse the intra-rater and inter-rater agreement. RESULTS: Considering the cumulative assessment of the Smile Esthetic Index (SEI), the ICC value for the inter-rater agreement of the 10 examiners was 0.62 (95% CI: 0.51 to 0.72), representing a substantial agreement. Intra-rater agreement ranged from 0.86 to 0.99. Inter-rater agreement (Fleiss' kappa statistics) calculated for each variable ranged from 0.17 to 0.75. CONCLUSION: The SEI was a reproducible method, to assess the esthetic component of the smile, useful for the diagnostic phase and for setting appropriate treatment plans.

Orthodontic approach to treat complex hypodontia using miniscrews in a growing patient.

This article reports orthodontic treatment of a case of hypodontia of five premolars in an 11-year-old female patient with a positive tooth size-arch length discrepancy in both dental arches. The patient had a straight profile with balanced facial growth. Setup manufacture revealed the possibility of achieving ideal occlusion by mesializing permanent molars up to 15 mm, in addition to keeping a primary molar in the dental arch. With the aid of absolute anchorage, the proposed mechanics was performed and the occlusion predicted in the setup was achieved, while profile and facial growth pattern were maintained. The use of miniscrews for extensive orthodontic movements was successful. Furthermore, one primary molar was extensively mesialized. The indication of gingivoplasty to correct gingival smile proved effective. This is considered a useful technique for orthodontists.

Alternative treatment for open bite Class III malocclusion in a child with Williams-Beuren syndrome.

Williams-Beuren syndrome (WBS) is a rare genetic condition that affects approximately 1 in every 20,000 - 50,000 live births. WBS children have specific skeletal deformities, dental malformations and rare lingual muscle dysfunction. The need for orthodontic and orthognathic therapy has arisen and has been considered a real clinical challenge even for experienced professionals, once it requires a complex and individualized treatment plan. This study reports a case of orthopedic expansion of the maxilla, in which a modified facial mask was used for protraction of the maxillary complex associated with clockwise rotation of the maxilla. In addition, special considerations about treatment time and orthopedic outcomes are discussed.

Clinical and oral findings of a patient with Simpson-Golabi-Behmel syndrome.

BACKGROUND: The Simpson-Golabi-Behmel syndrome (SGBS) is an overgrowth condition characterised by macrosomia, mental deficiency, large head, prominent skull sutures, midface deficiency, hypertelorism, broad nose, wide mouth, macroglossia, malocclusion, highly arched palate, and musculoskeletal and limb abnormalities. The aim of this case report is to present clinical and oral findings of an 8-year-old boy who had been diagnosed with SGBS. CASE REPORT: This patient had supernumerary nipples on the right side, cubitus valgus webbed fingers, scoliosis, umbilical hernia, a coarse face, macrocephaly, hypertelorism, a short broad nose, a wide mouth, a straight facial profile and hearing loss. The patient also had macroglossia, diastemas, over-retained primary tooth, absent mandibular permanent central incisors, and highly arched palate. Lateral cephalometric analysis revealed a large anterior cranial base, a large maxilla and mandible, a large inferior face height, and skeletal Class III jaw relationship. FOLLOW-UP: After extraction of the over-retained primary central tooth, a partial prosthesis was fabricated in order to maintain function. The patient has been recalled regularly at 6-month intervals for 2 years. Over the following years the prosthesis was replaced due to facial growth. CONCLUSION: Long term follow-up is essential for the patient with SGBS. Preventive dental care, including oral hygiene instructions, diet counselling and the use of fluoride has been implemented.

Occlusal Characteristics of the Primary Dentition Revisited.

The occlusal characteristics of the primary dentition of 130 children 3 to 6 years old were examined. Variables were the terminal plane relationship, primary canine occlusion, spacing, overjet and overbite relationships. The flush terminal plane was the most common finding. A Class I relationship of the primary canine occurred in 85% of the subjects. Spaced dentitions occurred 81% of the time, while the presence of primate spaces occurred in at least one of the four quadrants. The overjet relationship varied from +1 mm to 4 mm in all subjects, and the majority of children were considered to have a normal overbite.

Rubber dam isolation--key to success in diastema closure technique with direct composite resin.

The use of direct composite resin for diastema closure has technique advantages, including that the restorative procedure can be carried out in one appointment at a reasonable cost and without the removal of sound tooth structure. The use of a rubber dam for closing diastemas with composite resin is of paramount importance as it prevents moisture contamination and ensures increased gingival retraction compared to other techniques. This provides better access to the cervical area of the tooth, facilitating proper placement of resin to recreate the natural anatomical contours and contact point. Thus, there is a more natural adaptation of the restoration to the gingival tissue, avoiding a space between the papilla and the restored tooth. To illustrate the advantages of this technique, two diastema closure cases are presented using direct composite resin with rubber dam isolation.

Transcultural perception of maxillary midline diastema.

PURPOSE: Perception of maxillary midline diastema as an esthetic trait varies in relation to culture, age group, and racial background. Although midline diastema is accepted in Africa, there are few reports on interethnic perception of midline diastema among Nigerians. METHODS: Participants aged 19 to 45 years were selected from six geographical zones of Nigeria; one state was randomly selected from each zone, and a local government area (LGA) selected from each state. A structured questionnaire including a set of color smile photographs with varying sizes of maxillary midline diastema (narrowest=2 mm; widest=6 mm) was administered. Information sought was age, gender, socioeconomic group, tribe, presence of a midline diastema, and grading of attractiveness of smile. This information was evaluated using a Likert scale. RESULTS: A total of 402 subjects aged 19 to 45 years and a mean age of 36.3 years (±0.714) took part in this study. The highest proportion of subjects with midline diastema was aged 21 to 30 years (33.9%), females (29.8%), from the Hausa ethnic group (35%), and from the class II socioeconomic group (31.9%). Among the ethnic groups, Hausa had the highest (65%) preference for midline diastema. Females (58.8%) and those in the class II socioeconomic group (68.1%) also had the highest preference for midline diastema. There was a strong relationship between incidence of and preference for midline diastema (P=0.000). All ethnic groups rated maxillary midline diastema as attractive, especially when the width was within 2 to 3 mm (P=0.02). CONCLUSION: All ethnic groups perceived maxillary midline diastema to be an esthetic attribute, provided the width was within 2 to 3 mm.

Discriminative ability of the generic and condition specific Oral Impact on Daily Performance (OIDP) among adolescents with and without hypodontia.

BACKGROUND: The aims of this study were to (1) investigate to what extent the generic and condition specific (CS) forms of the oral impact of daily performance (OIDP) inventory discriminate between a group of patients with hypodontia and a group of patients having malocclusion, (2) assess the association of the generic and CS OIDP with severity and localisation of hypodontia, whilst adjusting for patients' age and sex. METHODS: A total of 163 patients aged 10-17 years were included in a cross-sectional study. Two groups were investigated: 62 patients with non-syndromic hypodontia and 101 non-hypodontia patients. Both groups had a malocclusion of similar treatment need. All patients underwent a clinical and radiographic examination and completed a Norwegian version of the generic and the CS OIDP inventory. CS scores were established for impacts attributed to hypodontia. RESULTS: The mean number of missing teeth in the hypodontia group was 6.2. The prevalence of generic and CS oral impacts in the hypodontia group were 64% and 30%, and the corresponding rates in the non-hypodontia group were 62% and 10%. The generic OIDP did not discriminate between the two groups with respect to overall scores. The CS OIDP discriminated strongly between patients with and without hypodontia regarding problems with emotional status, showing teeth, social contact, speaking and carrying out work. Compared to the non-hypodontia group, patients with hypodontia, with severe hypodontia (≥ 6 missing teeth) and upper anterior hypodontia were respectively 3.4, 2.5 and 7.0 times more likely to report any oral impact attributed to small teeth, gaps between teeth and missing teeth. CONCLUSIONS: Hypodontia and malocclusion patients report a considerable burden of oral impacts. The CS-OIDP measure discriminated most effectively between patients with and without hypodontia and was related to severity and upper anterior localisation of hypodontia.

Laypersons' esthetic perception of various computer-generated diastemas: a pilot study.

STATEMENT OF PROBLEM: Managing excess anterior spacing is a common problem in dental practice. During orthodontic or restorative treatment planning, clinicians must decide how to distribute this space. However, few reports are available in the dental literature about the attractiveness and esthetic impact of anterior spaces other than midline diastemas. PURPOSE: The purpose of this study was to compare the esthetic perception of 4 different anterior diastemas, including simian diastemas (symmetrical diastemas between lateral incisor and canine), diastemas suggested by Frush and Fisher (asymmetrical diastemas between lateral incisor and canine and between central and lateral incisor), and by Lombardi (slight midline diastema and 2 larger diastemas between central and lateral incisors), and a midline diastema. MATERIAL AND METHODS: A picture of a young woman's smiling face was modified by using photoediting software to create the 4 previously mentioned diastemas. The resulting pictures were presented to laypersons questioned in French public places. The participants were asked to rank the pictures from most to least attractive, then to rate them with a mark from 1 to 10. RESULTS: One hundred and five participants completed the questionnaire. The median ranks and scores attributed to the pictures from most to least attractive were as follows: simian diastemas, 1 and 8; Frush and Fisher diastemas, 2 and 7; Lombardi diastemas, 3 and 5; and midline diastemas, 4 and 4, respectively. The hierarchy (simian diastemas>Frush and Fisher diastemas>Lombardi diastemas>midline diastemas) could be established statistically for the scores (P=.03, P<.001, and P<.001, respectively) but not for the ranks when adjusting on subjects' sex and age (P=.11, P=.03, and P=.06, respectively). CONCLUSIONS: The results showed an esthetic hierarchy of anterior diastemas. The negative perception of anterior diastemas seems to mainly be related to the presence and width of a midline diastema. These results can guide clinical decisions for patients with excess anterior spacing.

Analysis of anterior dentoalveolar and perioral aesthetic characteristics and their impact on the decision to undergo a Phase II orthodontic treatment.

OBJECTIVES: Researchers have conducted extensive studies regarding dentoalveolar factors that affect anterior dental aesthetics; however, there is no consensus regarding how these factors affect orthodontic treatment decisions. Only a few studies have included multiple factors simultaneously. Therefore, the objective was to investigate if there are identifiable dentofacial and perioral aesthetic factors that bias laypeople towards discontinuing treatment after a phase I treatment with this fixed class II corrector. METHODS: An analysis of photos and dental casts of 60 children (23 males, 37 females) having received phase I orthodontic treatment with the Xbow appliance was conducted. Variables considered were incisor height and width measurements, incisor proportions, incisor angulations, vertical lip thickness, gingival/incisal display, smile width per cent, diastema, midline deviation, smile arc, gender, and use of a 2×4. A principal component analysis and a logistic regression were used to determine which factors related to a patient's likelihood of receiving further orthodontic treatment. RESULTS: Only the angulation of the right maxillary incisors was significantly related to a patient's likelihood (odds ratio 1.886 (1.004-3.466); P = 0.049) to proceed to phase II orthodontic treatment following phase I orthodontic treatment with the Xbow appliance. The odds of proceeding to phase II treatment were 86.6% greater with a one standard deviation increase in the angulation of the right central and lateral incisors. Other factors demonstrated trends but were not statistically significant. LIMITATIONS: Sample in subgroups was small, excluded smiles that did not expose the upper incisor crowns significantly, smiles in real life are observed three-dimensionally, other factors outside the aesthetic measurements were not considered in the analysis. CONCLUSIONS: In this sample, the angulation of the maxillary right incisors was the most significant factor influencing the decision to undergo an orthodontic phase II.