Extraction Of Upper First Premolars Research Articles

Evaluation of anchorage loss after en masse retraction in orthodontic patients with maxillary protrusion using friction vs frictionless mechanics: randomized clinical trial

ABSTRACT Objectives To evaluate anchorage loss after en masse retraction in bimaxillary dentoalveolar protrusion patients using friction vs frictionless mechanics. Materials and Methods Thirty patients with bimaxillary dentoalveolar protrusion needing extraction of upper first premolars and en masse retraction with maximum anchorage were included in this two-arm, parallel, single-center, single-blinded randomized clinical trial with a 1:1 allocation ratio using fully sealed opaque envelopes. Friction group retraction utilized elastomeric power chain between miniscrews and hooks crimped mesial to upper canines on 17 × 25 stainless steel archwire. Frictionless group used customized T-loop springs loading upper first molars indirectly anchored to miniscrews. Activation was every 4 weeks until full retraction. The primary outcome assessed was anchorage loss evaluated at cusp tip and root apex of the first molar. First molar rotation, incisor tip and torque, and root resorption of anterior teeth were evaluated on digital models and cone beam computed tomography taken before and after space closure. Results Anchorage loss at crown of first molar was significantly more in frictionless group by 2.1 mm (95% CI = −0.4 to 3.5), (P = .014), while there was no significant difference in anchorage loss at root apex between groups. Significant mesial in molar rotation of 6.672° (95% CI = 12.2–21.2), (P = 0.02) was greater in the frictionless group. Both groups showed comparable tip, torque, and root resorption values. No severe harms were reported. There was mild gingival overgrowth and inflammation in the frictionless group due to T-loop irritation. Conclusions Extra anchorage considerations are needed during en masse retraction when frictionless mechanics is implemented as higher anchorage loss and molar rotation were detected. No difference in tip, torque, and root resorption was observed.

Effectiveness of low frequency vibration on the rate of canine retraction: a randomized controlled clinical trial

To investigate the effectiveness of AcceleDent Aura vibrating device on the rate of canine retraction. Thirty-two patients requiring extraction of upper first premolars and canine retraction were randomly allocated with a 1:1 ratio into either no-appliance group or the AcceleDent Aura appliance group. Canine retraction was done applying 150gm of retraction force using NiTi coil springs on 16 × 22 stainless steel archwires. The duration of the study was 4 months. Models were collected and digitized directly after extraction of upper first premolars and at monthly intervals during canine retraction for recording the monthly as well as the total distance moved by the canine. Digitized models were superimposed on the initial model and data were statistically analyzed. Anchorage loss, rotation, tipping, torque and root condition were evaluated using cone beam computed tomography imaging. Pain was evaluated by visual analog scale. No patients were dropped-out during this study. There was no statistically significant difference between both groups regarding the total distance travelled by the canine (P = 0.436), as well as the rate of canine retraction per month (P = 0.17). Root condition was the same for the two groups. Regarding the pain level, there was no statistically significant difference between the two groups at day 0 (P = 0.721), after 24 h (P = 0.882), after 72 h (P = 0.378) and after 7 days (P = 0.964). AcceleDent Aura was not able to accelerate orthodontic tooth movement. Pain level couldn’t be reduced by vibrational force with an AcceleDent device during orthodontic treatment. Root condition was not affected by the vibrational forces.

“Managing Class II Div I Malocclusion with Clear Path Aligners Utilizing an Extraction-Based Treatment Approach: A Case Report”

This case report is based on the clear aligner treatment of an adult patient presented with class II div I malocclusion. The case was treated with the extraction of upper first premolars and interproximal reduction in the lower arch. Total 35 sets of upper aligners and 25 sets of lower aligners were delivered with the wear time of 22 hours per day for 10 days. The entire treatment course spanned a period of 14 months. Thus, the case study underscores the reliability of orthodontic treatment with clear aligners for addressing class II malocclusion. The discreet nature of these aligners not only enhances periodontal health but also increases patient acceptance. As a result, they are more likely to embrace and adhere to the treatment, fostering better overall outcomes.

Outcome differences after orthodontic camouflage treatment in hypo- and hyperdivergent patients – A retrospective cephalometric investigation

ObjectivesTo compare differences in outcome in skeletal and dental parameters in hypo- and hyperdivergent Class II patients after extraction of upper first premolars and comprehensive orthodontic treatment.Materials and methods37 Class-II-patients with dental camouflage treatment were divided into a hypo- (n = 18) or a hyperdivergent (n = 19) group depending on the mandibular plane angle (hypo: < 34° or hyper: ≥ 34°). Lateral cephalograms were available before (T1) and after (T2) treatment and were analyzed with customized measurements. Data from a growth survey served as a control and were used to calculate the actual treatment effect. Data were analyzed by one-sample Student’s t-tests and independent Student’s t-tests. Statistical significance was set at p < 0.05.ResultsThe measurements showed similar changes in both groups. The effects were mainly dentoalveolar. Hypodivergent patients showed an almost equal increase in anterior and posterior facial height, while hyperdivergent patients only showed an increase in anterior facial height.ConclusionsIn hyperdivergent patients, the anterior facial height increases despite camouflage treatment. This indicates a tendency towards bite opening and backward rotation of the mandible. Hypodivergent patients do not experience deepening of the bite.Clinical relevanceIn hyperdivergent patients with upper first premolars extraction the anterior facial height increased differently than in hypodivergent patients. This should be considered if a bite opening is a possible contraindication to treatment.

A Novel Method to Accelerate Orthodontic Tooth Movement Using Low-Intensity Direct Electrical Current in Patients Requiring en-Masse Retraction of the Upper Anterior Teeth: A Preliminary Clinical Report.

Shortening the duration of orthodontic treatment by speeding up the rate of tooth movement has become an essential goal for both orthodontists and patients. This preliminary report aimed to investigate the safety and effectiveness of a new intraoral removable electrical device in accelerating the en-masse retraction of the upper anterior teeth using low-intensity direct electrical current. This prospective preliminary interventional clinical study was conducted at the Department of Orthodontics, Faculty of Dentistry, Damascus University, Syria, between March 2019 and February 2020. The sample consisted of six patients (four females and two males; mean age: 19.55 ± 0.89 years) whose initial diagnosis was class II division I malocclusion, and their treatment plansuggested the extraction of upper first premolars followed by en-masse retraction. The electrical stimulation was applied on the maxillary anterior region during the en-masse retraction phase using a specially fabricated removable device that was designed by two coauthors of this manuscript (RIS, MYH). Patients were asked to wear their own electrical devices inside their mouths for five hours daily. The primary outcomes were the en-masse retraction rate and duration. The secondary outcomes were safety and patient acceptance. The average total retraction rate during the treatment period was 0.97±0.06 mm/month. The total amount of retraction achieved during follow-up was 5.65 ± 0.85 mm, which was about 91.86% of the space resulting from the extraction of the upper first premolars. The mean treatment duration to complete the en-masse retraction was 5.66±0.81 months. No side effects of the electrical stimulation were found during the follow-up. Low-intensity direct electrical current could be an effective method to accelerate orthodontic movement. The electrical accelerating device used in this study effectively increased the en-masse retraction rate of the upper anterior teeth without any side effects and with high patient acceptance.

Ortho-Surgical Management of An Adult Patient with Gummy Smile

Aim: This case report represents the clinical management of a Skeletal Class II adult patient with gummy smile treated by Orthognathic surgery. Background: Vertical maxillary excess (VME) is the most common skeletal deformity in Skeletal Class II which is treated by Anterior Maxillary Osteotomy (AMO) and Gummy Smile is the characteristic feature of VME in which the anterior part of maxilla is superiorly repositioned. Case Description: A 19-year-old patient reported our clinic with the complaint of forwardly placed upper front teeth. On extra oral examination, she had convex profile with posterior divergence and interlabial gap of 10mm and everted upper lip. The patient had a gummy smile of 8mm. Intra orally, she had Class II canine relationship on both sides with missing irt 16, 36, 46. Cephalometric values showed Class II skeletal base with protrusive upper and lower incisors and acute nasolabial angle. Initially orthodontic treatment was done and extraction of upper first premolars was planned during surgery. AMO was done with superior impaction of 4mm and posteriorly by 6mm. After 4 weeks of post surgery, the settling of occlusion using intermaxillary elastics was done. At the end of the treatment, the patient had Class I canine relationship on both sides with Skeletal Class I and overjet and overbite was 2mm. The patient gummy smile was reduced to 4mm which was accepted by the patient. Fixed retention was given in both the arches. The total treatment time was around 30 months. Conclusion: The proper diagnosis and appropriate treatment planning is the main key to achieve stable results in Orthodontics. An interdisciplinary approach with the orthodontist and surgeon will lead to achieve stable, functional and esthetic results.

Comparative treatment outcomes after bilateral extractions of maxillary second molars or first premolars in patients with class II malocclusion: a retrospective study

BackgroundThis retrospective cohort study aimed to compare treatment results between bilateral extraction of upper second molars (M2) and first premolars (P1) in terms of treatment timing, cephalometry, upper third molar alignment and relapse in the long-term.MethodsFifty-three consecutively treated Caucasian patients with a brachyfacial pattern, skeletal class I and dental class II requiring extraction in the maxilla due to crowding were retrospectively divided into group I (M2 extracted; N = 31) and II (P1 extracted; N = 22). Fixed appliances were inserted after extraction and after distalisation of the first molars in group I. Post-treatment lateral cephalograms were digitally analysed and compared between groups. Six to seven years later relapse and success of upper third molar alignment were clinically evaluated as well as orthodontic treatment duration, pre-treatment age and gender recorded.ResultsAfter debonding patients with second molar extraction showed significantly smaller values for the Wits-appraisal, but higher values for index and facial axis. Extracting first premolars caused significantly more retroinclination/−position of anterior teeth and an increased profile concavity, more relapse and less successful alignment of upper third molars. Orthodontic treatment duration, pre-treatment age and gender were not significantly different between groups.ConclusionsBilateral extraction of upper first premolars or second molars may solve dental crowding in skeletal class I dental class II patients with a brachyfacial growth pattern. Upper second molar extraction seems to affect maxillary third molar alignment, long-term stability and dental and soft-tissue cephalometric parameters positively, but no intervention proved to be clearly superior.

Effect of Submucosal Injection of Platelet-rich Plasma on the Rate of Canine Retraction – A Split-mouth Randomized Clinical Study

Abstract Introduction: The use of platelet-rich plasma (PRP) has gained popularity in orthodontics in the past decade. PRP is an autologous concentration of platelets rich in growth factors and is hypothesized to play a role in orthodontic tooth movement (OTM) due to its bone remodeling capacity. Objective: The aim of this study was to determine the effect of PRP on the rate of tooth movement in humans. Materials and Methods: Fourteen patients requiring bilateral extraction of upper first premolars were included in the study. PRP (×4) was prepared and injected in the alveolar mucosa, distal to canine on experimental sides. Canine retraction was initiated on the same day of PRP injection using NiTi closed coil springs on both sides. The amount of canine retraction was measured and compared between both sides at the 4th, 8th, 12th, and 16th weeks by measuring the distance between lateral incisor and canine on the cast. Results: Results showed mean displacement of 1.355 mm, 1.232 mm, 1.191 mm, and 1.085 mm on experimental side and 1.265 mm, 1.126 mm, 1.031 mm, and 0.879 mm on control side at the 4th, 8th, 12th, and 16th weeks, respectively. Although increased OTM (13.85% or 1.1 times faster) was observed on experimental side at all time intervals compared to the control group, the result was not statistically significant. Conclusion: 4× concentration of PRP does not accelerate OTM significantly.

Expanding the concept of orthodontic camouflage for a skeletal Class II camouflage case through the use of skeletal anchorage system

This study aimed to report the treatment steps in a 26-year male patient, presented with a class II div 1 incisor relationship on a class II skeletal base with increased vertical proportions. The case was complicated by missing lower second premolars and retained lower second deciduous molars. Severe crowding was evident in the lower arch with mild crowding in the upper arch. The overbite and the overjet were increased. Scissor bite was evident in the left buccal segment. Treatment involved extraction of upper first premolars and lower second deciduous molars, utilizing moderate anchorage using a preadjusted edgewise fixed appliance (0.022’’ X 0.028”) with Roth prescription. Treatment duration was 20 months in total. The envelope of discrepancy specifies strict rules when camouflaging class II cases. The ability to retract incisors and the use of class II mechanics are within limited range to avoid damage to the periodontium. The current case report showed that the ability of the clinician to retract incisors using TADs could be carried out with high rate of success and safety.

Skeletal, Dental and Soft Tissue Cephalometric Changes after Orthodontic Treatment of Dental Class II Malocclusion with Maxillary First Molar or First Premolar Extractions.

The aim of the present retrospective study was evaluating skeletal, dental and soft tissue changes of two groups of Class II patients orthodontically treated with extractions of upper first premolars (U4 group) and upper first molars (U6 group). In total, 21 patient records (9M and 12F; mean age 12.5 ± 1.2 years) were selected for the U4 group, and 38 patient records (17M and 21F; mean age 13.2 ± 1.3 years) were recruited for the U6 group. Twenty cephalometric variables were analysed on standardised lateral cephalograms at baseline (T0) and at the end of orthodontic treatment (T1). Means and standard deviations (SDs) were calculated for both groups and increments were calculated. After revealing the normal distribution of data with the Shapiro–Wilk test, Student’s t-test was used to compare variables at T0 between groups. A paired t-test was used to analyse changes between time points within each group, and Student’s t-test to compare differences between groups at T1. Both groups showed a significant increase in the distance among upper second molars and the vertical pterygoid line (PTV-maxillary second molar centroid U6 group: 6.66 ± 5.00 mm; U4 group: 3.66 ± 2.20 mm). Moreover, the distance of upper incisors to the palatal plane significantly increased (PP-maxillary incisor tip U6 group: 1.09 ± 1.52 mm; U4 group: 0.20 ± 2.00 mm; p = 0.061). Significant changes were found for overjet (U6 group: −4.86 ± 1.62 mm; U4 group: −3.27 ± 1.90 mm; p = 0.001). The distance between upper lip and esthetic plane showed a significantly reduction in both groups (ULip-E Plane U6 group: −2.98 ± 1.65 mm; U4 group: −1.93 ± 1.57 mm). No statistically significant changes were found in sagittal or vertical skeletal values. The significantly larger reduction of upper lip protrusion and overjet in the U6 group compared to the U4 group suggests preferring molar extraction treatment for severe Class II with protrusive soft tissues’ profile and increased overjet. Since no differences on vertical values were found, an increased SN^GoGn angle should not be considered a discriminating factor for choosing molar extraction treatment.

Comparing patient-centered outcomes and efficiency of space closure between nickel-titanium closed-coil springs and elastomeric power chains during orthodontic treatment.

To compare patient-reported pain, discomfort, and difficulty in maintaining proper brushing between nickel-titanium closed-coil springs (CS) and elastomeric power chains (PC) when used for space closure. The secondary aims were to compare plaque control and efficiency of space closure between these two force delivery systems. A total of 48 patients who required extractions of upper first premolars and distal movement of upper canines had the CS randomly allocated to either the right or left side. Blinding was applied at data collection and analysis. Primary outcomes were pain intensity measured on visual analog scale, pain onset and duration, discomfort, and difficulty in maintaining proper brushing from the start of canine retraction at baseline and at 6 and 12 weeks thereafter. Secondary outcomes were plaque scores and the rate of space closure. No significant differences in mean pain scores, pain onset, and duration at different time intervals between CS and PC were observed. The CS side was significantly less comfortable than the PC (P < .0001) and more difficult to keep clean (P = .008). No significant differences in plaque scores were observed between CS and PC groups at any time interval. CS produced a faster rate of space closure than did PC (P = .008). CS were less tolerated than PC by patients but produced an average of 0.5 mm more movement than did the PC during the 12-week study period.

Intrusion Effects on Maxillary Anteriors using Mini Implant Anchorage and K-Sir Loop in Subjects with Deep Overbite- A Cohort Study

Introduction: Various options to treat deep bites nonsurgically involve extrusion of posterior teeth or intrusion of anterior teeth. Intrusion of anterior teeth is required in patients with excessive incisal display and to correct deep bite in adult patients when extrusion of posterior teeth is not desirable. Aim: To compare the rate of intrusion and dento-alveolar effects on maxillary anterior teeth by Kalra-Simultaneous Intrusion and Retraction loop (K-SIR loop) and Mini implant anchorage in subjects with deep overbite. Materials and Methods: This prospective cohort study included 12 patients with Class I or Class II Div 1 malocclusion having an overbite and overjet of &gt;4 mm treated with therapeutic extractions of upper first premolars. Group A included six subjects treated using orthodontic Mini implants, while Group B had six subjects treated with K-SIR loop. Lateral cephalograms were taken before intrusion and retraction (T1) and at the end of six months (T2) into intrusion and retraction. Independent t-test and paired t-test was done for intergroup and intragroup comparison respectively. Results: The rate of intrusion was 0.38 mm/month and 0.31 mm/month for Group A and Group B, respectively. The amount of intrusion was significantly more in Temporary Anchorage Devices (TAD) group (p-value &lt;0.01). Conclusion: In the TAD group, rate and amount of intrusion was significantly higher. There is no difference in vertical control between the two modalities statistically significant amount of molar extrusion was seen with the K-SIR loop group.

Comparison of frictional forces during the closure of extraction spaces in passive self-ligating brackets and conventionally ligated brackets using the finite element method.

BackgroundThis study compared the frictional force resulting from the bracket/archwire interface and the stress at the root/periodontal ligament/bone interface, between passive self-ligating brackets and conventionally ligated brackets, during the space closure stage.Material and MethodsA cone beam tomography was taken to a female patient that required extraction of upper first premolars and passive self-ligating system; three months after its activation, a cone beam tomography was taken again. The designs of the maxillary bone and the entire system were possible through tomography images and stereomicroscopic photographs. Validation of the Finite Element Method (FEM) was achieved comparing the amount of movement seen through tomography images and the FEM. Space closure was simulated for each system through the FEM and a comparison was made between the frictional force at the bracket/archwire interface, and the root/periodontal ligament/bone interface.ResultsThe most significant representation of frictional force at bracket/archwire interface and bone stress was found at the conventionally ligated system, while the passive self-ligating system accounted for the highest distribution of stress over the root.ConclusionsThe FEM is an accurate tool used to quantify frictional force and stress concentration during the orthodontic closure. The passive self-ligating system was seen less frictional during the closure state compared to conventional brackets. Key words:Friction, orthodontic bracket, finite element analysis.

Comparative evaluation of the efficiency of canine retraction using modified Marcotte and T-loop retraction springs - A split-mouth, randomized clinical trial.

OBJECTIVE:The aim of this study was to compare the efficiency of canine retraction using modified Marcotte and T-loop retraction springs.MATERIALS AND METHODS:Twenty-four subjects with a treatment plan involving bilateral extractions of upper first premolars were included in the study. A split-mouth design was used to randomly allocate opposite quadrants to either modified Marcotte spring (MS) or T-loop spring (TLS) for canine retraction. Cephalometric radiographs and models were used to measure the rate of canine retraction (primary outcome) and compare the angular/rotational changes in the canines and anchorage loss in molars (secondary outcomes) following retraction. Subjective assessment of pain and discomfort was compared using visual analog scale (VAS). Paired and independent t-tests were used to evaluate changes.RESULTS:The mean amount and rate of retraction of the canine were found to be significantly higher for MS (3.56 ± 0.696 mm and 1.188 ± 0.232 mm, respectively) when compared with TLS (2.125 ± 0.472 mm and 0.71 ± 0.157 mm, respectively). Distopalatal rotation of the canine was also significantly lesser for MS (2.42°±1.868°) than TLS (5.65° ±2.84°, P < 0.001). However, the amount of anchorage loss and canine tipping were significantly higher for MS. Statistically significant higher values in the VAS score for TLS indicated greater discomfort.CONCLUSION:MS exhibited increased rate of retraction and rotation control when compared with TLS during sectional canine retraction. Patient comfort was better for MS as evidenced by the VAS scores. However, the amount of tipping and anchorage loss obtained with MS were significantly higher than TLS.

TADs assisted Camouflage Orthodontic Treatment of Class II Division 1 Malocclusion in a Non Growing Patient: A case report

Class II, Division I malocclusion has been described as the most frequent treatment problem in orthodontic practice. Aim &amp; objectives of the present case report was to evaluate the management of skeletal Class II division 1 malocclusion in non growing patient with extraction of upper first premolars. Clinical and cephalometric evaluation revealed skeletal Class II with Angles Class II division 1 malocclusion with mild mandibular anterior crowding and increased overjet, severe maxillary incisor proclination, mild mandibular crowding, exaggerated curve of spee, convex profile, incompetent lips, increased overjet and overbite. Maxillary first premolars were extracted followed by en-masse retraction of anteriors with the help of temporary anchorage devices (TADs) to avoid anchorage loss. Mandibular incisor was extracted to correct curve of spee. Following treatment marked improvement in patient’s smile, facial profile and lip competence were achieved and there was a remarkable increase in the patient’s confidence and quality of life.

Cephalometric evaluation of soft tissue changes after extraction of upper first premolars in class ΙΙ div 1 patients.

Introduction: Tooth extraction to provide sufficient space, or camouflage of underlying skeletal problems is quite common in orthodontics. The present study evaluated soft tissue changes after upper first premolars extraction in class ΙΙ div 1 patients. Material and Methods: 20 cases (15 females, 5 males), with a mean age of 17.8±2.9 years with class ΙΙ div1 malocclusion and normal vertical height, who needed upper first premolars extraction were selected. Pre- and post-treatment lateral cephalometric radiographs were digitized. Image analysis was conducted by View Box 3.1.1 software. Paired t-test was used for comparison of pre- and post-treatment results. Results: The relationship of upper and lower lip to E-line and B-line had significant reduction. Dental variables of U1-NA(mm), U1-NA(°), overjet and overbite showed statistically significant reduction. Interincisal angle had significant increase. There were no significant difference in lower incisor variables and skeletal variables like SN-GoGn and FMA. Conclusions: Extraction of upper first premolars in patients with class ΙΙ div 1 malocclusion resulted in normal position of lips as presented by Holdaway, Legan and Ricketts which play a role in aesthetic profile. However, the amount of lip retraction was different from patient to patient. Key words:Soft tissue, fixed orthodontic treatment, class ΙΙ div 1, upper first premolar extraction.

Retraction of the upper maxillary incisors with corticotomy-facilitated orthodontics and mini-implants

Abstract This report describes a case of 21-year-old female with severe maxillary protrusion, and class ІІ/1 dental relationship. The treatment plan was extraction of upper first premolars and retraction of the anterior teeth. Mini-implants were used to provide maximum anchorage to maintain the extraction space. To shorten the retraction time selective alveolar corticotomy was combined with orthodontic therapy. The treatment time was reduced without any adverse effects on the periodontium and the vitality of the teeth.

Successful orthodontic treatment of Class II division 1 malocclusion in a non growing patient : A case report

Aim &amp; objectives of the present case report was to evaluate the management of skeletal Class II division 1 malocclusion in non growing patient with extraction of upper first premolars. Clinical and cephalometric evaluation revealed skeletal Class II division 1 malocclusion with severe maxillary incisor proclination, convex profile, average mandibular plane angle, incompetent lips, increased overjet and overbite. After extraction of upper 1st premolars, canine retraction was done which was followed by retraction of severely proclined upper anterior teeth by judicious control of third order bend in rectangular stainless steel arch wire with “V” loop . For anchorage management, intra oral anchorage with tip back &amp; toe in bends in stainless steel arch wire was satisfactory. Following treatment marked improvement in patient’s smile, facial profile and lip competence were achieved and there was a remarkable increase in the patient’s confidence and quality of life. DOI: http://dx.doi.org/10.3329/bjodfo.v2i2.16165 Ban J Orthod &amp; Dentofac Orthop, April 2012; Vol-2, No.2, 41-45

Concentrations of selected elements in permanent teeth and enamel among a group of adolescent girls in relation to severity of caries

Background: Human teeth considered to be an important etiological host factor in relation to dental caries through its morphology and composition. Elements may incorporate in tooth structure during pre and post-eruptive period changing the resistance for caries. The aims of this study were to determine the concentration of selected major (Calcium and phosphorus) and trace elements (Ferrous iron, nickel, chromium and aluminum) in permanent teeth and enamel among a group of adolescent girls in relation to severity of dental caries Material and Methods: The study group consisted of 25 girls with an age of 13-15 years old referred by Orthodontists for extractions of upper first premolars (two sides). Tooth and enamel samples were prepared for chemical analysis according to method described by Lappalainen and Knuttila (1979). Dental caries was diagnosed by both clinical and radiographical examinations following the criteria of D1-4MFS index described by Muhlemann (1976). All data were analyzed using SPSS version 19. Results: The concentration of major elements in teeth and enamel (measured in % of dry weight) showed that Ca ions were higher than P ions. On the other hand the concentration of trace elements in teeth and enamel samples (measured in ppm) showed that Al ions was the highest followed by Ferrous Fe then Ni ions, while Cr ions were the least in concentration. All elements showed statistically highly significant difference in concentration between teeth and enamel samples. Ca/P ratio was higher in enamel than tooth, but the difference was statistically not significant. Major elements (calcium and phosphorus) in tooth and enamel samples recorded negative correlations with DMFS. Trace elements except chromium ions recorded positive correlations with DMFS. They were not significant except for nickel ions in tooth and aluminum ions in enamel. Conclusions: The presence of these elements in both teeth and enamel samples indicated that these elements present in our environment; as foods, water, and air so they incorporate through out the tooth layers during the pre-eruptive period of tooth development, and incorporate the outer enamel surface during the demineralization and remineralization processes that occurs in the post-eruptive periods. Ca and p ions play an important role in mineralization of tooth and enamel. Cr ions may play a role in improving mineralization and crystallity of teeth, while Fe, Ni and Al may act as cariogenic elements.

Class II division 1 malocclusion treated with extraction of upper first premolars: Case report

This report describes the treatment of a 13.7-year-old girl with a severe maxillary protrusion. She indicated Class II molar and canine relationship and showed 7-mm overjet, 0-mm overbite, and slight lower midline deviation with an unstable mandibular position. Treatment was started using a splint to stabilize the position of the mandible, followed by extractions of maxillary first premolars and fixed appliances to reduce lip protrusion. Molars were finished in a Class II relationship with canine guidance, and ideal overjet and overbite relationships were established. Also the final result was esthetically well balanced. The treatment results were stable 6 years after debonding.