Comparative evaluation and influence of new Optibond eXTRa self-etch Universal adhesive and conventional Transbond XT on shear bond strength of orthodontic brackets-An in vitro study.

INTRODUCTION: The demand by dental practitioners for adhesives led to the innovation of newer self-etched universal adhesive systems. The objectives were to evaluate the shear bond strength (SBS) of metal brackets bonded with Optibond eXTRa Universal self-etch adhesive and Transbond XT primer and also to assess the adhesive remnant index (ARI). MATERIALS AND METHODS: A total of 100 extracted human premolar tooth samples were divided into 2 groups (n = 50) according to the adhesive system employed: Transbond XT (3M Unitek) and Optibond eXTRa Universal (KaVo Kerr). In group A, Transbond XT primer was applied, and in group B, Optibond eXTRa was applied, and metal brackets (American Orthodontics) were bonded with the Transbond XT adhesive, followed by photopolymerization with LEDition. The samples were preserved in artificial saliva for 30 days. SBS was tested using a universal testing machine (DAK Series7200, India). The ARI was assessed at 10× magnification under a stereomicroscope (Meiji Techno, Japan). The SBS scores were subjected to independent sample t-test and ARI scores to Pearson's Chi-square test. RESULTS: The mean SBS and standard deviation of Transbond XT is 12.11 ± 2.6 MPa and that of Optibond eXTRa Universal is 11.36 ± 2.8 MPa, revealing a statistically nonsignificant difference. Transbond XT displayed higher ARI scores and was statistically significant (P = 0.001). CONCLUSION: The Optibond eXTRa Universal adhesive appears to be preferable for orthodontic bonding as it exhibited clinically acceptable SBS and performed better in terms of the ARI.

Management of an Unusual Ectopic Eruption of Maxillary Canine.

Transposition of teeth is a rare condition, with a prevalence of 0.3-0.4% in general population. They are more commonly observed in females, and may occur unilaterally/bilaterally with greater frequency of left side occurrence in unilateral transposition cases. A 17-year-old female patient reported with the chief complaint of unaesthetic smile. On clinical examination the patient was diagnosed with Angle's class I malocclusion with an ectopically erupted maxillary left canine labial to the left central incisor with retained deciduous canine. The treatment plan decided was to extract the retained deciduous canine, level and align the ectopic canine using an R-loop. The treatment for the patient was finished in 14 months and was retained using a fixed lingual retainer in the upper and lower arches.

Treatment of Skeletal Class II Malocclusion with Forsus Fatigue Resistance Appliance and Its Re-activation by Using Custom-made Crimp.

Growing skeletal class II malocclusions with mandibular deficiency have been treated for more than a century with different types of functional appliances. Removable or fixed functional appliances are available to advance the mandible. Fixed functional appliances have the advantage of not requiring patient compliance. They can also be used concurrently with brackets. This article presents the case reports of successfully treated mild skeletal class II in late stages of puberty by using a Forsus fatigue resistance appliance along with custom made crimp.

Efficacy of New Adhesion Promoters on Compromised Hypocalcified Enamel.

INTRODUCTION: The amount of technological progress occurred in the last few years has brought an add up to the benefits of bonding in Orthodontics. Research-based findings have constantly led to the development of new materials that are aimed to simplify the clinical procedures like bonding of brackets to compromised enamel surfaces. Hence, the present study is aimed to assess the bond strength of orthodontic brackets on fluorosed enamel using adhesion promoters. AIM: To evaluate the shear bond strength (SBS) of orthodontic brackets bonded on fluorosed enamel using conventional Transbond XT and new adhesion promoters such as Enhance LC and All Bond 3. MATERIALS AND METHODS: The study involved 90 non carious, extracted teeth with mild to moderate fluorosis randomly divided into 3 Groups. In Group - I (control group) the teeth were bonded with conventional Transbond XT and cured with LED light. In Group - II Enhance LC was applied to fluorosed enamel before bonding and in Group - III All Bond 3 was used. Shear bond strength was tested by using Universal testing Instron machine. ANOVA and Post-Hoc Tukey's tests were used to compare shear bond strength. Adhesive remnant on the tooth was assessed and scored using adhesive remnant index (ARI). RESULTS: Results showed a reduced SBS values (9.43MPa ±3.03) with conventional Transbond XT on fluorosed enamel. Among the adhesion boosters used Enhance LC illustrated lesser SBS values (12.03 MPa ± 4.42) compared with All Bond 3 (14.38MPa ±4.92). ARI showed bond failure at bracket resin interface in group I & group II and at enamel resin interface in group III although statistically insignificant. CONCLUSION: It was concluded that using adhesion boosters on fluorosed enamel showed higher bond strength compared to the control group. Among the two adhesion promoters used All Bond 3 expressed highest bond strength compared to Enhance LC although statistically insignificant.

Biomechanical considerations in mandibular incisor extraction cases.

Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases.

Soft tissue esthetic norms for mahabubnagar population of southern India.

AIMS: The Aim of the study was to establish Soft Tissue Cephalometric Norms for skeletal and dental relationships amongst the Mahabubnagar adult population. MATERIALS AND METHODS: Sixty subjects (30 Males & 30 Females) subjects from different part of Mahabubnagar in the age group 18-25 Years (Mean age 21.3 Years) were selected at random for the study and lateral cephalograms were taken. All the cephalograms were traced by two operators using conventional hand tracing. The parameters used in the study were taken from Arnett and Bergman soft tissue cephalometric analysis (STCA). Overall 46 measurements including 40 linear, 6 angular parameters were used. Mean and standard deviation values were calculated. The difference between males and females were evaluated using student t-test. RESULTS: The values obtained from the study showed significant difference in most of the parameters from that of Arnett et al., norms and between males and females within Mahabubnagar population. CONCLUSION: Males had thicker soft tissue structures, acute nasolabial angle, increased facial lengths and heights, increased midface deficiency, recessive lower face, more convex profile and less upright mandibular incisors than females within Mahabubnagar population.

Torque Loss in En-Masse Retraction of Maxillary Anterior Teeth Using Miniimplants with Force Vectors at Different Levels: 3D FEM Study.

OBJECTIVE: This FEM study was conducted to quantify the amount of torque loss in maxillary anterior teeth by applying force vectors from different levels to the anterior retraction hook at various heights and comparing with that of molar anchorage system. MATERIALS AND METHODS: Five 3D FEM models were constructed with force vectors at different levels: HOT-High Orthodontic Traction (13.5mm from archwire) to ARH1- Anterior Retraction Hook (5mm), HOT to ARH2 (8mm), LOT- Low Orthodontic Traction (8 mm) to ARH1, LOT to ARH2 and from conventional molar hook to ARH1. Mini-implants were placed buccally between the roots of second premolar and first molar. Torque loss was calculated by measuring the displacement of the teeth at crown tip and root apex in two planes i.e. sagittal and vertical using Y and Z axis respectively in all the five models. The results were statistically analyzed by using Kruskal Wallis ANOVA and Mann-Whitney U-test. RESULTS: HOT to ARH1 showed that the anterior teeth moved bodily (p =0.5127), followed by molar hook - ARH1(p=0.0495*) which showed mild uncontrolled tipping. Whereas the HOT- ARH2, LOT - ARH1,and LOT - ARH2 models exhibited uncontrolled tipping with maximum torque loss in LOT - ARH1 (p=0.0001*). CONCLUSION: It can be concluded that bodily movement with very minimal torque loss was observed in HOT-ARH1 model whereas the maximum torque loss was recorded in LOT-ARH2 model. Conventional molar anchorage group showed uncontrolled tipping with some amount of extrusion and anchor loss of posteriors.

Modification of uprighting spring for derotation of second molars.

One of the most efficient ways for the correction of rotated upper molars is derotation with a transpalatal arch, but this appliance is usually favourable when the need for correction is same on both sides of the dental arch. Derotation of unilateral upper second molar is a difficult task, especially when there is no accessible tooth/ any attachment is available distal to it for the application of couple forces. We have designed a modification of uprighting spring which is far more convenient than using the conventional method of TPA for derotation of unilateral upper second molar.

Early treatment of class III malocclusion with Petit facemask therapy.

Class III malocclusion with retrusive maxilla can be orthopedically corrected in the deciduous or mixed dentition, with reverse pull headgear in combination with or without rapid maxillary expansion. The advantage of expansion in these patients is to correct the posterior cross bite, and disarticulate the maxilla. This is a case report of successful treatment of developing skeletal class III malocclusion using Petit facemask without maxillary expansion. A 10-year-old girl presented with concave facial profile and decreased lower facial height. She had bilateral class III molar and canine relationships with reverse overjet of 3 mm and over bite of 6 mm. The treatment objective was to correct the skeletal class III to achieve a more harmonious facial profile. Patient was treated with Petit facemask, by applying a force directed at angle of 30 degrees to occlusal plane for a period of 4 months. The intra-oral appliance used was an acrylic cap splint without expansion. The post treatment results showed a significant improvement in facial profile with class I molar relationship and no change in treatment time when compared with patients treated by facemask therapy and maxillary expansion.