Impact of routine open-mouth osseous temporomandibular joint tomography on diagnosis and therapeutic options.

OBJECTIVES: The aim of this study was to evaluate the impact of routine open mouth osseous temporomandibular joint (TMJ) tomography on diagnosis and treatment planning of TMJ conditions. Investigating the need for such images is important to justify the additional radiation exposure imparted by such procedures. STUDY DESIGN: The records of patients who underwent closed- and open-mouth osseous TMJ tomography (planar film tomography up to the beginning of 2006; cone beam computed tomography from 2006 onward) were reviewed. Three examiners formulated a diagnosis and treatment plan based on the history, clinical findings, and tomography interpretation reports of closed-mouth images. Then they reviewed the interpretations of the open-mouth images and recorded whether they would change their original diagnosis and/or treatment plan on the basis of the findings. Descriptive analysis of the results was performed. RESULTS: The impact of routine open-mouth imaging on diagnosis and treatment planning was variable among the examiners. Examiners 1, 2, and 3 had a change in diagnosis in 7%, 5%, and 3% of cases, respectively, and a change in treatment plan in 1%, 1%, and 8%, respectively. CONCLUSIONS: Routine open-mouth osseous TMJ tomography had a minimal impact on diagnosis and treatment planning of TMJ conditions, which varied according to the treating clinician.

Retention practices and factors affecting retainer choice among orthodontists in Saudi Arabia.

OBJECTIVES: To identify the retention protocols practiced by orthodontists in Saudi Arabia, and the factors affecting retainer choice.  METHODS: This cross-sectional study took place between February and March of 2015 at the College of Dentistry, University of Dammam, Dammam, Saudi Arabia. A previously tested electronic survey of 34 items was sent to all 1,200 orthodontic members of the Saudi Orthodontic Society. The questionnaire elicited data on the subjects' demographics, orthodontic treatment practices, retention, and post-retention protocols.   RESULTS: One hundred and sixty-seven (13.9%) responses were received during the study period. The results showed predominant use of Hawley in the maxillary arch (61.3%), and fixed lingual in the mandibular arch (58.5%). Approximately 90.3% recommended full-time maxillary removable retainer wear. Overall, orthodontists who performed fewer extractions tended to use fixed retainers, and those who performed more extractions used removable retainers (p=0.018). Interproximal enamel reduction was used by 28% of the respondents as an adjunct procedure to enhance retention. Approximately 64% practiced a post-retention phase of retainer wear. Participants who used removable retainers most commonly prescribed lifetime retention.  CONCLUSION: Hawley in the maxilla, and fixed lingual in the mandible were the most common retention protocols prescribed. Lifetime retention was the most common choice for participants who used removable retainers, especially when extractions were carried out.

Evaluation of the fit of preformed nickel titanium arch wires on normal occlusion dental arches.

AIM: To determine the fits of preformed nickel titanium (NiTi) archwires on dental arches with normal occlusion. METHODS: Forty sets of upper and lower plaster models were obtained from men and women with Class I occlusions. Preformed 0.016″ × 0.022″ NiTi archwires from Rocky Mountain Orthodontics (RMO), 3 M Unitek, Ormco, and Dentaurum were evaluated in terms of their fits on dental arches from male, female, and combined cases. Data were analyzed by using fourth- and sixth-order polynomial equations, analysis of variance (ANOVA), and the Duncan post hoc test. RESULTS: In the upper arches, the best fit and least error were obtained with RMO Ovoid and Ormco Orthos Large archwires for male cases, but with 3 M Orthoform LA archwires for female and combined cases. In the lower arches, the best fit and least error were obtained with Ormco Orthos Large for male cases, with 3 M Orthoform LA and RMO Normal for female cases, and with 3 M Orthoform LA, RMO Normal, Ormco Orthos Large, and Ormco Orthos Small for combined cases. When both dental arches were matched, Ormco Orthos Large was the best wire for male cases. 3 M Orthoform LA was the best wire for female and combined cases. CONCLUSIONS: Using an archwire form with the best fit to the dental arch should produce minimal changes in the dental arch form when NiTi wires are used and require less customization when stainless-steel wires are used.

Live demonstration versus procedural video: a comparison of two methods for teaching an orthodontic laboratory procedure.

BACKGROUND: To measure the effectiveness of procedural video compared to live demonstration in transferring skills for fabricating orthodontic Adam's Clasp. MATERIALS AND METHODS: Forty-nine fourth-year undergraduate male dental students were randomly assigned to two groups. The students in group A (n = 26) attended a live demonstration performed by one faculty, while students in group B (n = 23) watched a procedural video. Both the procedural video and live demonstration described identical steps involved in fabricating the Adam's Clasp. Students in both groups were asked to fabricate an Adam's Clasp in addition to completing a questionnaire, to measure their perceptions and satisfaction with the two teaching methods and lab exercise. Blind assessment was performed by one faculty for both groups. RESULTS: The mean students' scores in the fabrication of the Adam's clasp were 6.69 and 6.78 for the live demonstration (group A) and the procedural video (group B), respectively. No significant difference was detected between the two groups (P = 0.864). Statistically significant difference was found in the mean response between the two groups for statement 6 on the questionnaire, "The steps in the teaching method were presented in a clear fashion and were easy to understand". A higher mean response for group B was found compared to group A (P = 0.049). No significant differences were found between the two groups for the other statements (P > 0.05). CONCLUSION: Procedural video is equally as effective as a live demonstration. Both methods should be considered in teaching undergraduate orthodontic courses in order to improve the learning experience and to match different learning preferences of students.

Characteristics of Down syndrome subjects in a Saudi sample.

OBJECTIVE: To compare the cephalometric characteristics of Down syndrome (DS) subjects with those of normal subjects. MATERIALS AND METHODS: Cephalometric radiographs of 60 Saudi DS subjects and 60 controls with specific inclusion criteria were used. Descriptive statistics were used to describe the quantitative and categorical variables, and the Student's t-test for two independent samples was used to compare the mean values of quantitative variables. RESULTS: SBa and SN were higher in controls than in DS subjects, whereas the NSBa was significantly higher in DS subjects than in controls. SNA, Co-A, ANB, and A-Na perp of controls were higher than the DS subjects. However, SN-MP, PP-MP, ANS-Me/N-Me, Y-axis, and Ar-Go-Me of the DS subjects were higher than those of the controls. In addition, U1-NA, U1-NA mm, L1-NB, and L1-NB mm of the DS subjects were also higher than the controls with a more acute U1-L1 angle in DS. NLA was larger in controls than in DS, whereas LL-E and UL-E of the DS subjects were higher than the controls. CONCLUSIONS: Differences between DS subjects and controls can be found when examining cephalometric radiographs. Anterior and posterior cranial base lengths are shorter with a backward inclination of the posterior cranial base in DS subjects. DS subjects present with a retrognathic maxilla and shorter effective length, with an increased LFH and a hyperdivergent mandible. Bimaxillary dental protrusion can also be expected in DS subjects with prominent lips and a reduced nasolabial angle.

Cephalometric craniofacial features in Saudi parents and their offspring.

OBJECTIVE: To estimate the correlation and heritability values of craniofacial variables between parents and their offspring. MATERIALS AND METHODS: The sample comprised 24 Saudi families; each family consisted of father, mother, son, and daughter. Lateral cephalometric radiographs were taken for each family member. Twenty-eight angular, linear, and proportional cephalometric variables were measured. Interfamilial correlations and heritability (h(2)) values were estimated among father-son, father-daughter, mother-son, and mother-daughter pairings. RESULTS: The most similar angular measurements between parents and offspring were related to mandibular variables, which were as follows: MP-SN degrees , MP-FH degrees , SNB degrees , and SNPog degrees ; facial height dimensions and mandibular body length were among the highest similar linear variables. Lower facial height percentage had greater resemblance to parents with regard to proportional measurements. Both the correlation coefficients and the heritable values of these characteristics were stronger in the father-offspring than the mother-offspring pairings. The daughters' cephalometric craniofacial characteristics were more affected by the parents than were those of the sons. CONCLUSIONS: The overall correlation and h(2) mean values for the three types of measurements showed stronger values in the father-offspring than the mother-offspring groups, with the father-daughter pairings more significant than the father-son groups.

Sella turcica morphology and dimensions in cleft subjects.

OBJECTIVES: Evaluate sella turcica morphology, calculate its size in cleft subjects, and compare it with noncleft subjects. MATERIALS: Lateral cephalometric radiographs of 95 cleft and 190 noncleft individuals. Radiographs were divided into two groups by age: 11 to 14 years of age, 15 years and above. MAIN OUTCOME MEASURES: The morphology of the sella turcica was categorized into six shapes; whereas, the size of the sella turcica was measured in terms of length, depth, and diameter in millimeters. RESULTS: The sella turcica was abnormal in shape in the majority of cleft subjects when compared with noncleft subjects (p= .0000), more so in subjects with unilateral cleft lip and palate and bilateral cleft lip and palate (p= .0000, p= .020, respectively). Depth of sella turcica was smaller in unilateral cleft lip and palate subjects (p= .037). A smaller sella turcica size (length, depth, diameter) was evident in cleft subjects as compared with noncleft subjects (p= .037, p= .004, p= .000, respectively). Age correlated positively with an increase in sella turcica size in both noncleft and cleft subjects (p= .000, p= .009, p= .000). CONCLUSIONS: A majority of cleft subjects displayed an abnormal appearance of sella turcica when compared with noncleft subjects. A smaller depth of sella turcica was associated with unilateral cleft lip and palate. The sella turcica was smaller in size in cleft subjects than in noncleft subjects. Sella turcica size increased with age in subjects with and without clefts.

Mathematical analyses of dental arch curvature in normal occlusion.

OBJECTIVE: To present a comprehensive mathematical analysis of dental arch curvature in subjects with normal occlusion. MATERIALS AND METHODS: The materials studied were 40 sets of upper and lower plaster dental casts of subjects presenting with normal occlusion. The sample was equally divided into casts from male and female subjects with an age range from 18 to 25 years. Curve-fitting analyses was carried out and four main categories of functions were considered: the beta function, natural cubic splines, polynomial equations, and Hermite cubic splines. RESULTS: The polynomial function (fourth order) was found to be a reasonable analysis when the objective is to describe the general smooth curvature of the dental arch, while a Hermite cubic spline is more appropriate when it is desired to track arch irregularities, such as evaluating treatment changes. CONCLUSIONS: Due to its advantage in providing a more naturally smooth curve, the fourth-order polynomial function may be used as a guide to fabricate customized arch wires, or even an entire fixed orthodontic appliance system.

The shape and size of the sella turcica in skeletal Class I, Class II, and Class III Saudi subjects.

The purpose of this study was to describe the shape and measure the size of the sella turcica in Saudi subjects with different skeletal types. Lateral cephalometric radiographs of 180 individuals (90 males and 90 females) with an age range of 11-26 years were taken and distributed according to skeletal classification; 60 Class I, 60 Class II, and 60 Class III. The sella turcica on each radiograph was analysed and measured to determine the shape of the sella, in addition to the linear dimensions of length, depth, and diameter. A Student's t-test was used to calculate differences in linear dimensions, while a one-way analysis of variance was performed to study the relationship between skeletal type and sella size. The results show that the sella turcica presented with a normal morphology in the majority of subjects (67 per cent). No significant differences in linear dimensions between genders could be found. When age was evaluated, significant differences were found between the older (15 years or more) and the younger (11-14 years) age groups at the 0.01 and 0.001 levels for length, depth, and diameter. Sella size of the older age group was larger than in the younger age group. When skeletal type was compared with sella size, a significant difference was found in the diameter of sella between the Class II and Class III subjects (P < 0.01). Larger diameter values were present in the skeletal Class III subjects, while smaller diameter sizes were apparent in Class II subjects (multiple comparison tests). When gender, age, and skeletal type were all compared with the size of the sella (regression analyses), age was significantly related to a change of length (P < 0.01) and diameter (P < 0.001). Sella shape and dimensions reported in the current study can be used as reference standards for further investigations involving the sella turcica area in Saudi subjects.

The association between posture of the head and malocclusion in Saudi subjects.

The purpose of the present study was to examine whether a relationship exists between posture of the head and neck, and the presence of certain malocclusal problems. Dental models, in addition to lateral cephalometric radiographs, taken in the "natural head position" of 180 male and female subjects were obtained. The postural angles between the head and the cervical column, termed craniovertical, craniocervical, cervicohorizontal, and cervical curvature, were measured. The malocclusal traits studied were: molar relation, crowding, spaces, overbite, overjet, crossbites, and midline displacements. Results show that a relationship between crowding and head posture could only be found in subjects with upper arch crowding and cervical curvature (p<0.01). A significant difference in craniocervical and cervicohorizontal angles was observed in subjects with overbite, compared to subjects without overbite (p<0.01, p<0.001). The influence of gender on overbite and head posture was also found to be strongly correlated (p<0.05). With regard to molar relation, Class II malocclusion showed a stronger relation with craniovertical and cervicohorizontal angles than both other classes (p<0.05, p<0.01). A significant correlation was found between craniovertical angles NSL/VER and overjet, irrespective of gender or age (p<0.05). Crossbite was strongly correlated with all craniocervical angles (p<0.05). It can be concluded that certain malocclusal problems are more strongly associated with head posture than others, and that crowding does not seem to play a major role in this association in the present study.

Growth status of Saudi patients with cleft lip and palate.

OBJECTIVE: The purpose of this study was to determine if the type of cleft had any influence on the growth achievement of the affected patients. METHODS: The height, weight and head circumference of 63 cleft patients attending the Orthodontic clinic at the College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia between the year 2000-2001, were compared with each other according to the type of cleft present. In addition, a comparison was made between the height and weight of cleft subjects with that of the normal population. RESULTS: The most common type of cleft present was unilateral cleft of the lip and palate, followed by bilateral cleft of the lip and palate, and cleft lip. When the height, weight and head circumference of cleft patients was compared, no significant difference could be found between any groups. In addition, no significant difference could be found between height and weight of cleft patients versus that of the normal population. CONCLUSION: We can conclude from this study, that normal achievement of height, weight and head circumference is to be expected in children with cleft of the lip with or without cleft of the palate.