Search

Enlarged adenoids are often associated with oral breathing. The latter can impact the dental arches. The purpose of this study was to determine the relationships between dental arch measurements and the size of adenoids.A cross-sectional study was carried out on 86 children. The dimensions of the adenoids were determined from nine radiographic evaluation methods and the dental arch measurements made on the casts. The association between the grade of adenoids and the dental arch measurements was sought by Spearman correlation. That between the quantitative variables assessing adenoids and dental arch measurements was sought by Pearson correlation. The strength of these associations was analyzed using Cohen's values in 1988. The significance was set at p = 0.05.Palatal depth was significantly and positively correlated with adenoid grade according to the method of Holmberg and Linder-Aronson (rho = 0.55, p = 0.005) and with the adenoid measurements according to the methods of Kemaloglu, Fujioka, Johannesson, De Menezes and Maran with r respectively equal to 0.65, 0.59, 0.63, 0.47, 0.74; and p respectively equal to 0.001, 0.002, 0.001, 0.019, and0.001. It was also significantly but negatively correlated with the adenoids measurements according to Hibbert's method (r = -0.52, p = 0.008). Overbite was significantly and negatively correlated with adenoid dimension using the De Menezes method (r = -0.541, p = 0.006).The strength of the associations shows that using respectively Maran and De Menezes methods can allow to better highlight the association between the dimensions of the adenoids and the palatal depth and the overbite.

Replacing impression by intraoral camera is a paradigm shift. However no in vivo independent studies have compared the accuracy of analog impressions with three systems of digital impression. Are digital recordings precise enough for our orthodontic practices?Five impressions of the maxillary and mandibular arch of the same subject were conducted in vinylpolysiloxane, cast in plaster type IV then scanned by a laboratory scanner (VPS group). A model (maxilla and mandible) is the reference. Five scans of the maxillary and mandibular arch of the plaster model reference (group EXO) and the subject in intra-oral (INTRA group) were performed successively by the Lythos™ cameras (Ormco) version 1, iTeroThe images of the INTRA group have a lack of accuracy of 18 microns (p = 3.88 10Carried out under ideal conditions, the accuracy of the cameras is certainly less than conventional impressions VPS but is clinically sufficient. The reduction of acquisition time may affect the accuracy, smooth out errors and get the arches contracted.

Tooth-arch discrepancy is a disproportion between dental volume and bone base. Extraction therapy can be a solution in case of excessive tooth volume and insufficient basal bone length. Techniques including bone distraction popularized by Ilizarov in the fifties allow the increase of the basal arch length in the maxilla as well as in the mandible.We will describe the procedure of this dental arch length augmentation since the reflection about the therapeutic plan until the sufficient arch length is obtained and describe the indications of this orthodontic and surgical treatment in case of dental crowding, buccal and labial inclination and functional problems.Distraction is an interesting technique to be considered for the management of macrodontia that allows to get enough basal bone lenght to reach the therapeutic goal.

A possible relation between an upper airway space decrease and the development of obstructive sleep apnea syndrom explains the importance to know the effect of the modification of dental arch length on the upper airway during orthodontic treatment.The aim of this article is to expose recent knowledge about upper airway development and dental arch length decrease factors, to determine the influence of this decrease on upper airway development.A review was done to determine the upper airway normal development, to define dental arch to specify if an ideal position of dental arch on apical base exists. All of the length dental arch decrease factors during orthodontic treatment (dental extraction, dental agenesis and dental malpositions) and their upper airway resounding were searched.Some authors found a diminution of upper airway space after premolars extractions while others didn't found this diminution after extractions premolars when incisor retraction is finished. A decrease of transversal maxillary diameter and nasal cavity may be due to absence of permanent teeth.The effect of dental arch length decrease during orthodontic treatment in the upper airway development was not scientifically proved. However we had to be vigilant and adapt our orthodontic treatment case by case to avoid an upper airway modification.

A transverse dimension deficiency is most often the result of functional disorders. Poor tongue posture at rest and during function as well as digit-sucking give rise to deficiencies which are initially alveolar but which, with time, frequently end up becoming skeletal. The combination of functional rehabilitation and transverse dimension treatment is the best way to avoid many relapses. We need to monitor this anomaly closely, from diagnosis to retention. Otherwise, failure awaits us.

Prosthetic teeth size and placement must be in perfect harmony with the bucco-facial structures for a successful and esthetic removable prosthesis. This study aimed to determine among young Senegalese black people facial index estimating maxillary central incisor width and distance between canine points starting from bizygomatic width.621 black Senegalese participated to this transversal study. Measurements were made using anthropometric slide caliper and electronic slide caliper. The comparative analysis was carried out by the test t of Student. The correlative analysis used the chi-square test. The risk of error was fixed at 5%.Positive correlations were found between variables. Distance between canine points was significantly (p = 0.000) correlated to bizygomatic width and central incisor width. Using bizygomatic width, the average dividing factors to estimate central incisor width and distance between canine points were respectively 15.13 and 3.75.Distance between canine points and central incisor width can be given starting from bizygomatic width, as guide of selecting maxillary anterior prosthetic teeth width.

Despite the importance of taking the primary dental impression, this act remains unfortunately neglected by most practitioners. Think to succeed a total removable prosthesis from a failed primary dental impression is a challenge for the practitioner and seems utopia. For this, you wish through our work give the importance to the choice of the mass-produced impression tray that is paramount for the success of the primary dental impression. This study examines a sample of 160 plaster primary models (80 maxillary and 80 mandibular) from primary dental impression carried out with mass-produced impression trays whether or not modified for new total edentulous patients having consulted at the University Dental centre in Casablanca for a prosthetic rehabilitation by total prosthesis. Thirty-six women and 44 men have been selected. The study showed that men have maxillary and mandibular arches longer and wider than those of women, and that the average value for several parameters measured is close to the measurements of the maxilla trays U3 and mandibular L3; Where the need for acquisition of large size dental impression tray, in accordance with the dimensions of our population in order to meet our expectations, namely: to respect the integrity of the support surfaces, to meet the mechanical qualities of the prosthesis, to restore the aesthetics and function by minimizing the grievances of the toothless total subject.

The role of obstructive tonsils in dental arches abnormalities is widely discussed in the literature but remains controversial. Data on the probable relationship between obstructive tonsils and the presence of these orthodontic abnormalities are subjective. The objective of this study is to quantify the relationship between the obstructive character of the tonsils and the dental arches measurements.A cross-sectional study was performed in children aged between 6 to 12 years divided into 2 groups (A and B) according to the obstructive character of the tonsils. Dental intra- and inter-arches measurements are recorded on each child. Data is analyzed using SPSS 20.0 for Windows. A t Student and chi square tests are respectively used to compare quantitative and qualitative variables according to the obstructive character of the tonsils. The level of significance is fixed at p = 0.05.The upper dental arch depth is significantly more important in subjects with obstructive tonsils (group B). Dental arches widths are significantly more important in subjects without obstructive tonsils (group A). Group B subjects are significantly more likely to have class II malocclusions, open bite and posterior cross bite with mandibular lateral deviation than group A subjects.Early evaluation of children with obstructive tonsils can prevent dental intra- and inter-arches abnormalities caused by upper airway obstruction. Thus late and more aggressive treatments which are not always as efficient as when they were performed during childhood will be avoided.

Sagittal soft-tissue analyses made from photographic records (sagittal photogrammetric analysis of the soft tissues) allow orthodontists to quantify the sagittal dimension and situation of the facial soft tissues. These tissues maintain close anatomical relationships with the underlying dental arches. However, little importance has been given to the description and the comparison of the sagittal soft tissue morphology according to dental arches parameters. The purpose of this study was to determine the correlation between the sagittal photogrammetric soft tissue profile and the dental arches measurements.A cross-sectional study was performed in a group of students. Standardized facial-profile photographs were taken with each student in natural head position, and relaxed lip posture. Photogrammetric parameters were measured on paper sheet using a graduated ruler. Dental arches measurements were also performed directly into the mouth with an electronic caliper. The strength of the association between sagittal photogrammetric soft tissue measurements and dental arches parameters was investigated by a Pearson's correlation. Results were regarded as significant at p=0.05.The lips protrusion parameters were significantly and positively correlated with the dental arch lengths. The overjet was significantly and positively correlated with Ls/Sn-Sm. The overbite was significantly and negatively correlated with the sagittal labial parameters Ls/N-Ort, Li/N-Ort, Ls-E, Li E, Ls-S, Li S, Ls/Sn-Sm and Li/Sn-Sm.The correlations found in this study show the importance of taking into account the soft tissue in the diagnosis and orthodontic treatment of patients.

Upper airways obstruction can result in the reduction of the transversal dimensions of the maxillary arch which affect the vertical and the sagittal dimensions. The PNIF measure is an objec- tive and cheap way to assess the upper airways permeability. The aim of this study was to determine the relationship between PNIF and dental arch sizes.Seventy eight patients (40 girls and 38 boys) age ranged 10-15 years were included in this cross sectional study. The PNIF was measured with a Youlten peak flow meter (Clement Clarke International, London, United Kingdom). The sagittal, vertical and transversal dimensions of the dental arches were evaluated on dental casts with a digital caliper (Mitutoyo Corporation, Tokyo, Japan). T test was used to assess differences in PNIF and dental arches variables between subjects grouped according to sex (male and female). The Pearson's correlation coefficient was used to analyze the relationship between the dental arches sizes and the PNIF. The significance was set at p0.05.PNIF rate was higher in girls than in boys but the difference was not significant. There were sexual dimorphism regarding the anterior and total lengths of the upper arch, the total length of the lower arch and the maxillary intermolar width which are significantly more important for boys (p respectively equal to 0.05; 0.03; 0.04 and 0.04). The PNIF was significantly and negatively correlated with the total length of the upper arch (r = -0.25). The others measurements did not show significant correlation with PNIF.Others parameters are needed to complement the peak nasal inspiratory flow rate for the respiratory disorders related dental arches sizes abnormalities diagnosis.

Summary In the context of this study, a clinical audit of cases treated by a single orthodontist was carried out to illustrate one practical application of the PAR index. Fifty pairs of dental casts taken from the patient group before and at the end of orthodontic treatment were evaluated by an orthodontist trained in the use of the PAR index. This evaluation shows that the average overall PAR score for the subjects included in the study fell from an initial value of 25.64 ± 11.73 points to 1.78 ± 2.79 points at the end of orthodontic treatment. The average reduction attributable to orthodontic treatment was 23.86 ± 0.95 points, for an average percentage reduction of 93.36 ± 9.02%. When cases were classified according to the degree of improvement suggested by the nomogram of the PAR index, 23 (46%) were in the “Improved” category after treatment, and 27 cases (54%) in the “Greatly improved” category. This adds up to a total of 100% in these two categories, with none in the “No better” or “Worse” categories. It should be recalled that a high standard of orthodontic treatment is considered to be reached when the average percentage reduction of the PAR score exceeds 70% and when the number of cases in the “Worse or no better” category is below 5%.

In a retrospective multicentre study, the success rate and efficiency of activator treatment were analysed. All patients from two University clinics (Giessen, Germany and Berne, Switzerland) that fulfilled the selection criteria (Class II division 1 malocclusion, activator treatment, no aplasia, no extraction of permanent teeth, no syndromes, no previous orthodontic treatment except transverse maxillary expansion, full available records) were included in the study. The subject material amounted to 222 patients with a mean age of 10.6 years. Patient records, lateral head films, and dental casts were evaluated. Treatment was classified as successful if the molar relationship improved by at least half to three-fourths cusp width depending on whether or not the leeway space was used during treatment. Group comparisons were carried out using Wilcoxon two-sample and Kruskal-Wallis tests. For discrete data, chi-square analysis was used and Fisher's exact test when the sample size was small. Stepwise logistic regression was also employed. The success rate was 64 per cent in Giessen and 66 per cent in Berne. The only factor that significantly (P < 0.001) influenced treatment success was the level of co-operation. In approximately 27 per cent of the patients at both centres, the post-treatment occlusion was an 'ideal' Class I. In an additional 38 per cent of the patients, marked improvements in occlusal relationships were found. In subjects with Class II division 1 malocclusions, in which orthodontic treatment is performed by means of activators, a marked improvement of the Class II dental arch relationships can be expected in approximately 65 per cent of subjects. Activator treatment is more efficient in the late than in the early mixed dentition.

The gold standard management of mandibular fractures is open reduction and osteosynthesis associated with intermaxillary fixation. The use of intermaxillary fixation screws for 20 years has considerably reduced the number of intermaxillary fixation with arch bars. The aim of our review was to identify current indications and contraindications of each technique.We present a short history and compare the two techniques with recently published assets, drawbacks, and complications.The indications of intermaxillary fixation screws are uni- or bifocal fractures without or with minimal displacement. Their use is contraindicated in any other type of fracture, which should still be treated with arch bar fixation.

To evaluate and compare the dentoskeletal effects associated with surgically assisted rapid maxillary expansion (SARME) performed with (+) and without (-) pterygomaxillary disjunction (PD), utilizing cone beam computed tomography (CBCT).A retrospective study of 9 patients (1 male, 8 females, mean age 18.9 years) undergoing SARME who were divided into two groups. In group (-PD) the surgical technique followed involved bilateral LeFort I type of osteotomy plus midline osteotomy. In group (+PD) same protocol was followed and pterygoid disjunction was performed additionally. Three-dimensional CBCT scans were obtained preoperatively and 3-6 month postretention. A Hyrax type acrylic bonded expander was used. MIMICS 14.0 (Materialise Europe, Belgium) software was used to evaluate transverse expansion at skeletal, dentoalveolar and dental level. Additionally dental inclinations, alveolar bending and the pattern of expansion sagittally were assessed. Wilcoxon's and Mann Whitney U tests were used for comparisons.All linear transverse measurements at dental and dentoalveolar level were found to have a statistically significant increase (P0.05) in both treatment groups. No statistically significant differences were found between the two groups as well as within groups on skeletal level (except of the anterior expansion of maxilla between piriform rims bilaterally). In -PD group significant buccal tipping of the 1(st) premolar was observed as well as increased buccal bending of the alveolar crest.This study confirms that SARME is an effective treatment of maxillary transverse deficiency. CBCT is an adequate tool to assess dentoskeletal treatment effects.

Performing Le Fort I impaction osteotomy can be compromised or impossible. The intranasal volume of the lower turbinates prevents an important maxillary impaction. In this case, horseshoe osteotomy is an alternative.The first step is to lower the inferior edge of the pyriform aperture and the anterior floor of the nasal fossae with a bur. The palatine alveolar wall is cut through resection of the maxillary sinus anterior and lateral walls. The maxillary dental arch may be impacted without freeing the vomer or cutting through lateral walls of the nasal fossa, after having dissected the palatine fibrous mucosa and disjoined the pterygomaxillary suture.This technique has mainly been used in pre-implantation surgery to lower the maxillary crest in edentulate patients, and to increase the crestal height after bone grafting without modifying the position of the hard palate. It is a good alternative to the usual Le Fort I osteotomy for important impactions when the alveolar bone height is sufficient.

Based on the principle of the sphere of MONSON, the Broadrick flag technique constitutes a relatively simple means to determine the plan of occlusion, by using a radius fixes of 104 mm. The theory of MONSON was debated a long time. Our work consists of a clinical study realized in the CCTD of Casablanca, on 31 completely toothed cases normocclusion. Its objective was triple: to calculate on the profile teleradiographies, the anatomical and geometrical rays used for the construction of SPEE curve, to see if there is concordance between these two rays and finally to compare them with the theoretical value of 104 mm. From the obtained results it would seem that: The 104 mm value, cannot be considered as a standard average to be used to determine the curve of occlusion, also the articulator such as it is designed currently cannot be used in all the patient's about is the values of their rays. In the absence of molars, the anatomical radius cannot be used in place of the geometrical radius to determine the curve of occlusion. The measured gap between the obtained curve and the plan of occlusion remains not insignificant, he can reach 3 mm for the anatomical radius and 3,5 mm for the geometrical radius. In the total edentate, the cephalometric determination of occlusion plane, by basing itself on the anatomical radius or the geometrical radius is not possible.

The purpose of this work was to compare transverse dimensions of the maxillary and mandibular arches in the canine and molar region between three groups of patients: the first group had an occlusion in class II division 1, the second one a dental class II division 2 and the third one, a class I bite. Our sample is composed of 94 patients, with an average age of 20 +/- 3 years: 31 patients presented a class I occlusion, 33 a class III1 and 30 cases presented a dental class II2. For this study, we measured, on the maxillary and mandibular dental casts of each patient, the intercanine and intermolar canine (central inter fossa). Comparison of variables was conducted using the variance analysis ANOVA; the selected post-hoc test is the Bonferrroni test. On the basis of our study, we can get the following results: Maxillary intercanine distance is narrower in class II1 compared to class II2 of 2 mm "p0.05". Mandibular intercanine distance is narrower in class III1 compared to class II2 of 1, 3 mm "p0.05". Maxillary intermolar distance (inter fossa) is narrower in class II1 compared to class I of 2, 2 mm "p0.05".

In the mixed dentition, lower incisor crowding can exist. He may be transitory or increase with dental arch evolution because of reduction of arch length by loss of leeway space. Early diagnosis allows the instauration of interceptive therapy, to ovoid extractions. Preserve or loss leeway space will depend of orthodontic space management. The clinical case presented in this article shows the interest of early treatment of incisor crowding to preserve arch length and make the leeway space available to resolve the crowding.

Severe mandibular incisor crowding with bone insufficiency is usually treated by dental extractions and orthodontic management. Symphyseal distraction was proposed to avoid tooth extraction. This technique is still considered as invasive, complex and unsafe. We evaluated symphyseal distraction to clarify its indications, and to suggest a simplified surgical protocol.Six patients were treated by symphyseal distraction: three with a bone-anchored device and three with a dental anchored one. Pre and postoperative inter-canine measurements and occlusal stability were analyzed.Postoperative inter-canine measurements increased from 3.4 to 6.8mm (mean 5.2mm). All patients were in Angle class I occlusion without complications. Dental anchored device simplified the surgical procedure.Symphyseal distraction with dental anchored device is a simple, efficient and reliable to treat severe transverse mandibular deficiency. The orthodontist can manage the procedure by himself and controls the whole expansion process according to specific requirements.

It is apparent that tooth movement is enhanced by procedures that elevate the remodeling of alveolar bone, and of periodontal and gingival fibrous tissues. The periodontally accelerated osteogenic orthodontics (PAOO) also termed as Wilckodontics, involves full-thickness labial and lingual alveolar flaps accompanied with limited selective labial and lingual surgical scarring of cortical bone (corticotomy). Most of the authors suggest that the RAP is the major stimulus for alveolar bone remodeling, enabling the PAOO. However, we propose that detachment of the bulk of dentogingival and interdental fibers from coronal part of root surfaces by itself should suffice to stimulate alveolar bone resorption mainly on its PDL surfaces, leading to widening of the periodontal ligament space which largely attributes to accelerated osteogenic orthodontics. Moreover this limited fiberotomy also disrupts transiently the positional physical memory of dentition (PPMD), allowing accelerated tooth movement. During retention period, a new biological and physical connectivity is generated that could be termed as new positional memory of the dental arch.

The purpose of this study was to compare digitized models with their current gold-standard plaster models for tooth-size discrepancy and Bolton analysis. Fifteen pairs of plaster models were obtained from orthodontic patients with permanent dentition. These were digitized and evaluated using the Bibliocast Cecile3 v2.5 software. Two examiners measured three times the mesiodistal width of all the teeth and the arch length, and determined the tooth-size discrepancy and Boltons ratios. The plaster models were measured using a digital vernier caliper. Interclass correlation (ICC), mean differences and paired t-tests were used for comparisons and statistical analysis. The ICC of the digital models were 0.930 (0.852≤ICC

In the past orthodontists frequently used extra-oral force to slow down skeletal growth in their treatment of Class II malocclusions; more modern practice relies less on applying distal force to the maxilla than on stimulating forward growth of the mandible. Does this change in therapeutic design have any repercussions in facial esthetics? To evaluate the impact of treatment on the appearance of the profile, we conducted a study with 64 patients in the adolescent dentition stage with a Class II, division 1 malocclusions. None had teeth extracted or preliminary orthodontic treatment. We divided them into two sections; we treated the first group of 33 patients with the Distal Active Concept (DAC), which encourages forward movement and growth of the mandible, and we treated the second group of 31 patients with Extra-Oral Force (EOF) in combination with a full-banded appliance. Comparing the results with cephalometric profile analyses, we found that the soft tissue contour of the lower part of the face showed considerably more sagittal development in the children treated by DAC than those treated by EOF.

Minor facial asymmetries that can be detected in newborn infants indicate that facial growth for this child will also be asymmetric. When practitioners observe a displacement of the mandible in temporary dentition it probably indicates the presence of asymmetric masticatory function and they should look for an inter-temporal axial asymmetry by tracing cutaneous landmarks in the vicinity of the external ears. If they find the possible presence of asymmetric remodeling of glenoid fossas, they have to anticipate future temporo-mandibular disorders. By using a measurement grid (Orthogrille type) placed on the teeth of the upper plaster cast, they can assess sagittal and transverse status of the temporary teeth. If indicated, they can use acrylic plates fitted with sectional distalizing or expansion screws designed for full or partial arch correction. They can also modify the upper occlusal plane inclination by using acrylic bite blocks that keep all of the teeth from occluding and thus allow the displaced mandible to return to symmetrical movements during mastication and at the same time allow the temporal bones to remodel symmetrically. Finally, they can re-center the two dental arches and their midlines with a Frankel re-centering device that will also restore harmony to respiratory and vocalization functions. Thanks to this type of orthopedic treatment carried out for patients before they reach the age of six the asymmetric direction of their facial growth will become normal and the functioning of their temporo-mandibular joints will become optimal.

The aim of this comparative retrospective short- and long-term study was to evaluate the interceptive treatment in Class III malocclusion in daily orthodontic practice. The sample was composed of 69 children divided into two groups according to the interceptive treatment applied: 31 children in group F (facial mask) and 38 in group M (interceptive fixed appliance). A Pancherz cephalometric analysis was carried out on the lateral head films at the start of the study (t(0), after the active treatment (t(1) and 29 months after t(1) (t(2). The two groups were compared at the beginning of the study by t-test and chi-squared test: there were no difference between groups M and F except for facial divergence, which was greater in group M. Long-term comparison (interceptive and post-interceptive stage i.e. six years) showed that (i) overjet was corrected in each group: molar discrepancy was stable in both groups, (ii) alveolar discrepancy was stable and (iii) antero-posterior discrepancy was not improved in either group. At t(2) there were no differences, either qualitative or quantitative between groups M and F. In the end, more than 80% of the children did not need an orthognathic surgery.

Using the Treil 14 points cephalometric model orthodontists can prepare a complete cranio-facial anatomic assessment at three analytic levels: the framework or envelope, the basal bone and the alveolo-dental arcade. The assessment of border-line surgical antero-posterior dysmorphosis can elucidate interesting depictions of asymmetries, their relation to other malformities, and their genesis. Asymmetry arises from over-growth of one side of the face in all three dimensions of space even if, clinically, it often appears that one dimension is predominately affected. The ortho-morphic cases of Angle Class I present a little right excess or "natural" asymmetry. The Class III cases present a severe excess on the right side, while the Class II cases present an excess on the left side comparing with reference sample.

The aim of temporary retention is not to eliminate every causes of relapse and to ensure the stability of treatment, but to eliminate one cause of relapse: the periodontal reactions consecutive to the orthodontic displacement of teeth. The other causes of relapse must be eliminated by the treatment itself, and not by retention. To be effective the retention must be immediate, complete and prolonged. The most used temporary retainers are: the Hawley retainer, the vacuum-retainers and the bonded retainers. None of which is perfect. Only the permanent retention can ensure the stability whatever the cause of relapse. The risks of permanent retainers are not yet well known.

Orthodontists often observe the clinical sign of supraclusion, or deep overbite, in their patients, a condition that is difficult to correct and that relapses frequently. In order to treat it with the most appropriate therapy, orthodontists should have a precise understanding of its etiology, which can be skeletal, neuromuscular, or dental and may often result from an intricate web of factors. In preparing their diagnoses, orthodontists should examine the possible mechanisms of its installation and evaluate them in an architectural cephalometric analysis of the oral prehensile complex.

Insufficient attention paid to dental arch forms during orthodontic treatment can give rise to relapses. The aim of this study was to calculate the mean dental arch form of the Senegalese subject and to suggest a characteristic polynomial function. Our sample comprised 57 Senegalese subjects aged between 13 and 33 years displaying an ideal occlusion. By superimposing all the arch curves of the different subjects in the series and by adopting intermolar distance as the standard unit, we were able to calculate the mean maxillary and mandibular arch forms and suggest a polynomial function of 6 degrees enabling production of almost perfect reproductions of these forms.

Nowadays, the demand for esthetic dental treatment is fundamental and is conditioned by gender, age and level of education. The color and appearance of teeth and crowding in the anterior segment feature among the main factors governing the choice of treatment. The aim of this article is to check six basic parameters needed to obtain an esthetic result.

Tooth-size assessment is a useful indicator of dental crowding which constitutes one of the main parameters in tooth-size arch-length discrepancy (TSALD). Systematic TSALD evaluation is imperative in all patients consulting for dentofacial orthopedic treatment. The present study aims to compare four measurement techniques for calibrating tooth size. It was performed on casts taken from 30 Moroccan patients consulting at the Dentofacial Orthopedics Department of the Rabat School of Dentistry. Four measurement methods were used to calculate the largest mesiodistal diameter of mandibular teeth mesial to the first molars. Statistical analysis showed that the methods using a digital caliper, the analog vernier caliper and the computerized technique are reliable, accurate, and interchangeable. In contrast, the analog caliper with no vernier is less accurate.

The main objectives of this study are to present a literature review of self-etching primer's (SEP's) and present the outcomes of a prospective clinical trial to assess the clinical bond failure rates of orthodontic brackets bonded using a self-etching primer (SEP), compared with brackets bonded using a conventional acid-etched technique with a control adhesive (Transbond). A secondary aim was to investigate whether characteristics of the operator, patient or tooth bonded had any influence on bracket failure.Single-centre randomized controlled clinical trial. Thirty-four patients were bonded, each being randomly assigned to either the test or control adhesive.Orthodontic Department Countess of Chester Hospital, Chester, UK.Orthodontic patients requiring fixed appliance treatment.Bond failure.Failure rates over the initial 6-month period were 2.0% (Transbond) and 1.7% (SEP) with no statistically significant difference between the two groups. Over the duration of the fixed appliance treatment, bond failure rates increased, but remained acceptable at 7.4% (TB) and 7.0% (SEP), respectively. When operator, patient and tooth characteristics were analysed, only the bracket location was found to be significant. Maxillary brackets were more likely to fail than mandibular brackets (relative risk 0.47%; 95% confidence interval 0.22, 1.03). The failure rate for brackets in our study was low when compared with previous studies.Both the acid-etched control and self-etching primer in combination with adhesive pre-coated brackets were successful for clinical bonding. Their combined failure rate was lower than that reported in similar trials. The literature on SEP's supports the findings of this study.

The author explains in this clinical note how the direct bonding method can be most efficiently utilized. He suggests that precision of placement and comfort for patients can be improved if the following two rules are respected: the attachments must be kept horizontal and the substrate must remain immobile.

Surgical management of transversal discrepancies is a special field of orthognathic surgery. Long-term stability is often challenging despite the various available surgical techniques. We present herein a little known surgical technique for discrepancy correction: mandibular constriction. The surgical technique is described and its indications are discussed.

The purpose of this study was to validate an experimental model of weakened synthetic mandible loaded in a device simulating masticatory forces by studying the reproducibility of the fracture threshold.Both sides of five synthetic mandibles were weakened by progressive synthetic bone resection. The synthetic mandibles were submitted, after each resection, to static chewing exercises in the simulator. The threshold fracture was recorded.The fracture threshold mean resection height was 19.33 mm with a percentage of error of 6.72%.The low percentage of error allowed us to validate this experimental model. A comparison with other experimental or finite element models confirmed our protocol and results. We plan to apply this protocol to fresh weakened mandibles.

Missing maxillary lateral incisors create a major esthetic problem due to their strategic position in the smile. The two treatment approaches commonly taken are creating adequate space to prosthetically replace the missing lateral incisors or closing the spaces and replacing the missing lateral incisors by the canines. This article will discuss indications, advantages, disadvantages and problems encountered in cases of space opening and space closure for missing laterals. The amount of space to be created, the preparation and the timing for implant placement, the bone volume, the implant size and prosthetic considerations will also be discussed. The methods for reshaping canines and building them up to simulate lateral incisors in orthodontic space closure, and positioning the canines and first premolars - so that they resemble to the teeth they are replacing - will be described.

The eight points cephalometric Treil model and the alveolodental parameters already allows an initial description of the maxillofacial framework and the teeth. Added six points allows taking into consideration an intermediate level: the maxillary and mandibular skeletal basis. So, the 14 points complete model allows a complete craniofacial anatomy description in three analysis levels: the framework or envelope, the osseous bases, the alveolodental arch. The correlation study between the 3D parameters at different levels defines the compensation notion. It allows understanding how skeletal disharmony may be distributed among the different levels. Only vertical direction compensations are analysed here.

A 3D cephalometric analysis method from scanner acquisition has been developed thanks to a long collaboration between Dr Treil and the Department of Orthodontics in Toulouse III University. It allows a perfect knowledge of maxillo-facial architecture using fourteen landmarks related to the neuromatricial axis of facial growth. These landmarks can be identified without ambiguity. The marking of each tooth relative to dental arches (gravity centre coordinates and torque and tipping of each tooth), and the location of arches relative to maxillo-facial frame are given by the analysis. Description and reconstruction of dental and maxillo-facial anatomy are possible with three levels: maxillo-facial frame, maxillar and mandibular bases and dentoalveolar level. The method not only gives more precise information than conventional cephalometrics in anteroposterior and vertical directions, but it allows transversal analysis and asymmetry measurement. Applications are numerous in research as well as in clinical medicine: analyses of cases border line surgery, surgical set-up, facial asymmetry, analysis of dentoalveolar compensations, definition of therapeutic aims, occlusal analysis and set-up, study of evolution in anthropology-primatology, study of growth etc. This method of description using a pattern of landmarks is perfectly adapted to the last developments of modern research techniques: morphometric geometry with Procustes superimpositions, EDMA, TPS, FEM.

Crowding and mal-positioning of teeth in the dental arch are problems frequently encountered with adult patients. These discrepancies are associated with a lack of development of basal bone, a shortcoming whose etiology is difficult to discern. Treating these problems with expansion assisted by surgery depends on osseous distraction, the separating of segments of bone to create new bone and the movement of whole groups of teeth and their periodontium, a technique that assures excellent stability. It is important to define precisely the indications for this technique as well as our therapeutic protocols, both in the maxilla and in the mandible. For an expander we use a single thread expansion screw welded to two molar bands. To be sure it works effectively; the surgeon first opens the maxillary suture to liberate the two portions of the maxilla. After a ten day wait, the expansion screw is opened daily for up to two weeks depending on how much expansion is required. When the desired point is attained, the expansion device is locked, and the patient returns for check-up visits every ten days. During this period the patient is outfitted with a false tooth to mask the large and unsightly diastema that has appeared between the central incisors. Three months after the original intervention the patient receives a full-banded strap-up. The orthodontist usually employs centripetal forces to level the teeth and to correct rotations in an effort to minimize the risk of periodontal complications. The results that we have obtained with this treatment have fulfilled our expectations with significant improvement in arch form, full respect for the periodontium, an improvement in facial balance, and the appearance of a generous and pleasing smile.