Canine Relationship Research Articles

Bolton’s Ratios for Indian Population, Can We Follow The Ideal Standards Blindly?

Introduction: Various studies have been conducted which show that interarch tooth size relation differ with population. The aim of this study was to find out Bolton ratio in Indian population. Methods: Measurement were taken from 50 study models of randomly selected males and females with class I molar and canine relationship with ideal overjet and overbite, who had not undergone any orthodontic or cosmetic dental treatment previously. Needle point dividers were used to measure the greatest mesio-distal diameter of all teeth. From the obtained data, the Kolmogrov-Smirnov test, standard error of mean, standard deviation, coefficient of variation, coefficient of correlation were measured and used to assign statistical significance. Results: Increased anterior ratio (79.2284) & decreased overall ratio (90.9464) in selected Indian population were found in relation to Bolton’s ideal ratio. Conclusions: - Differences between original Bolton ratio and obtained ratio for Indians were significant, specific standards for Indians might be needed.

Unilateral maxillary molar distalization using zygoma-gear appliance

The aim of the present case report was to present the treatment of a patient with Class II subdivision using the zygoma-gear appliance (ZGA) for unilateral maxillary molar distalization and fixed appliances for the further treatment needs. The ZGA consisted of a miniplate, an inner bow and a sentalloy closed coil spring. Three weeks after the miniplate was placed on zygomathic buttress, a distalization force of 350 g was unilaterally applied to the maxillary left first molar through the sentalloy closed coil spring. After a distalization period of 6 months, a super Class I relationship was achieved and the maxillary left first molar moved 5 mm distally without anterior movement of the anchor premolars. In addition, the maxillary left molar slightly tipped distally (2.4΀), the maxillary incisors slightly retruded (about −5΀) and the overjet decreased (−1.4 mm). Then, preadjusted fixed appliances (0.022 Χ 0.028-in, Roth system) were placed in both arches and the maxillary premolar and canine were distalized using the miniplate anchorage after the leveling and alignment procedure. Class I molar and canine relationships, acceptable overjet and overbite were established in a total treatment time of 18 months.

Skeletal Discrepancy Correction In Class II Div 1 Malocclusion Using Fixed Twin Blocks.

This case report describes the management of a male with a severe Class II skeletal discrepancy, Class II molar and canine relationship bilaterally, a large overjet and an impinging overbite . As the patient was in CVMI stage 4,it was planned to make use of remaining growth for correction of skeletal discrepancy and so the treatment was initiated with a fixed twin block. This promoted the growth of the mandible, restrained maxilla in anteroposterior direction which in combination with the fixed appliances for alignment and levelling of the dentition improved the convex soft tissue profile. Thus severe skeletal Class II discrepancy was successfully managed with the combination of functional correction along with comprehensive fixed mechanotherapy without any extraction resulting in acceptable soft tissue changes.

An alternative choice: Obtaining space for a canine with asymmetric fan type expansion appliance

A 12-year old female patient presented with her unesthetic appearance while smiling. The patient had a vestibule positioned upper-left canine, beside mesofacial face type, flat profile, Class II molar and canine relationships clinically. Dental crowding was 7.8 mm in the upper arch and 4.1 mm in the lower. Treatment plan included to obtain space for the upper-left canine using a modified fan type expansion appliance, followed by comprehensive fixed orthodontic treatment. The aim of this case report is to present a non-extraction treatment of a patient using asymmetric fan type expansion appliance.

Thirty-two-year follow-up study of Herbst therapy: A biometric dental cast analysis

The aim of this study was to analyze the very long-term effects of Herbst treatment on toothposition and occlusion. Fourteen patients from a sample of 22 with Class II Division 1 malocclusions consecutively treated with the banded Herbst appliance were reexamined 32 years after therapy. Dental casts were analyzed from before (T1) and after (T2) treatment, and at 6 years (T3) and 32 years (T4) after treatment. Minor changes in maxillary and mandibular dental arch perimeters and arch widths were seen during treatment (T1-T2) and posttreatment (T2-T4). Mandibular incisor irregularity remained, on average, unchanged from T1 to T2 but increased continuously during the 32-year follow-up period (T2-T4). Class II molar and canine relationships were normalized in most patients from T1 to T2. During the early posttreatment period (T2-T3), there was a minor relapse; during the late posttreatment period (T3-T4), molar and canine relationships remained, on average, unchanged. Overjet and overbite were reduced to normal values in all subjects during treatment (T1-T2). After treatment (T2-T4), overjet remained, on average, unchanged, but overbite increased insignificantly. Thirty-two years after Herbst therapy, overall, acceptable long-term results were seen. Stability was found in 64% of the patients for sagittal molar relationships, in 14% for sagittal canine relationships, in 86% for overjet, and in 86% for overbite. A Class II relapse seemed to be caused by an unstable interdigitation of the occluding teeth, a persisting oral habit, or an insufficient retention regimen after treatment. Most posttreatment changes occurred during the first 6 years after treatment. After the age of 20 years, only minor changes were noted. Long-term posttreatment changes in maxillary and mandibular dental arch perimeters and widths as well as in mandibular incisor irregularity seemed to be independent of treatment and a result of physiologic dentoskeletal changes throughout adulthood.

COMPREHENSIVE ORTHODONTIC TREATMENT OF PALATALLY IMPACTED MAXILLARY CANINES

Comprehensive orthodontic treatment among adult patients that required multidisciplinary approaches has been increased since a lot of them could not avail themselves with any treatment decades ago. Treatment of impacted canine in adult orthodontic patient needs to be integrated into the overall orthodontic treatment scheme. The following case report described an orthodontic treatment of 33-year-old woman with convex profile, palatally impacted of left maxillary canines and single dental crossbite. Dental midline shift associated with narrow arch form of upper arch and asymmetric tooth amount. Management of this case was started by extraction of first upper premolars in the opposite site from impacted maxillary in order to overcome dental discrepancy problem. Surgical exposure allowed the potency natural eruption of the impacted tooth. After 24-months of treatment, the impacted maxillary canines took place as integral elements in dentition and Class I Canine relationship was achieved. The success of this comprehensive orthodontic treatment also considered biomechanical and periodontal condition during treatment based on proper evaluation and good prognostic of the impacted tooth position. Providing adequate space and surgical exposure during levelling aligning phase followed by orthodontic traction and gingivectomy, were the multidisciplinary approaches of this following case. In conclusion, biomechanical orthodontic treatment related to periodontal condition must be considered in comprehensive orthodontic treatment of adult patient.

Factors related to orthodontic treatment time in adult patients

The length of time that it takes an orthodontist to treat adult patients varies widely. The aim of this study was to investigate how different variables influence treatment time. Seventy clinical case reports of successfully treated adult patients were examined. The patients were selected from 4,723 records held by three experienced orthodontists. The influence exerted by the following variables on treatment time was assessed: age, sex, facial pattern, severity of malocclusion (measured by the PAR index), sagittal relationship of canines, type of brackets (ceramic or metal), tooth extractions, missed appointments and orthodontic appliance issues/breakages, the latter being the dependent variable. Assessment was performed by multiple linear regression analysis, followed by the stepwise method with p < 0.05. The number of times a patient missed their appointment (no-show) (R² = 14.4%, p < 0.0001) and the number of appliance issues/breakages (R² = 29.71%, p = 0.0037) significantly affected variability in treatment time, and these two variables together can predict 43.75% (R² total) of the overall variability in treatment time. Other factors, such as canine relationship at the beginning of treatment, bracket type (metal or ceramic), tooth extractions, age at start of treatment, severity of the initial malocclusion, sex and facial pattern had no significant bearing on treatment time. The duration of orthodontic treatment in adults, when performed by experienced orthodontists, is mainly influenced by factors related to patient compliance. However, several factors which were not included in this study may contribute to variability in orthodontic treatment time.

Disyunción y extracción de primeros premolares maxilares en maloclusión clase II división 1- paciente mesofacial

The patient was a healthy 9 year old boy with malposition of the teeth in mixed dentition, in the facial profile analysis, an apparent increase in the lower third of the face is noticed, jaw is slightly retrognatic. .Class II Div 1 malocclusion, Incomplete eruption of dental piece 11, piece 12 has not erupted. (Tooth Identification , FDI system), showing slight giroversion of lower central incisors, overjet increased 5.5 mm, crossbite of upper right supporting area (primary pieces: canine, first and second molar). Upper midline was coincident with facial midline, teeth midline maxillary and mandibular aren’t coincident in centric occlusion or centric relation. , their mandibular dental midline is shifted 1½ mm to the right of the patient in centric occlusion and centric relation. He was treated with orthotics (maxillary disjunction) and orthodontics through the extraction of maxillary first premolars, upper incisor retrusion, leveling and alignment of the upper and lower dental arches. The total time of active treatment in the different phases was 5 years 10 months. Pre and Post treatment records are shown. Overjet, overbite and Spee curve are evident in the standard, and excellent alignment and symmetry in the dental arches. At the end of the case Class II molar and Class I canine relationship Is noticed. We obtained a very good facial aesthetics, no clinical discrepancy between OC and RC. The TMJ was free of symptoms.

Angle Class II malocclusion treated with extraction of permanent teeth

Angle Class II malocclusion associated with anterior open bite in adult patients demands a carefully elaborated orthodontic planning, aiming at restoring not only harmonious dental and facial esthetics, but also a balanced masticatory function. Orthognathic surgery or permanent teeth extraction are often the choice of treatment, therefore, treatment decision is related to all dental, skeletal and functional aspects. The present report discusses orthodontic compensation carried out by means of upper premolar extraction performed to correct the Class II canine relationship and, consequently, the anterior open bite, accepting that the upper incisors be retroclined. This clinical case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements for obtaining the BBO Certification.

Treatment of Class II Division 1 Malocclusion using Cervical Headgear

Class II division 1 malocclusions have many variation and treatment options. Choosing the right treatment begins with a correct diagnosis. The aim of this article is to describe treatment of Class II division 1 malocclusion in a growing patient using combined cervical headgear and non-extraction fixed orthodontic therapy. Class I molar and canine relationship was achieved with normal overbite and overjet. There is improvement in jaw relationship and facial profile. This correction was achieved by downward displacement and inhibition of the forward growth of maxilla with favorable growth of mandible, upper molar distalization and retraction of upper incisors from cervical headgear use. There was neither downward rotation of the mandible nor maxillary first molar extrusion. Treatment time, favorable mandibular growth pattern and patient compliance proved to be determining factors in the success of this treatment. DOI: 10.14693/jdi.v16i3.106

Mini Screw Orthodontic Implant as Temporary Crown Restoration to Replace Unilateral Missing Lateral Incisor Post-Orthodontic Treatment

Mini Screw Orthodontic Implant as Temporary Crown Restoration to Replace Unilateral Missing Lateral Incisor Post-Orthodontic Treatment

Longitudinal occlusal changes during the primary dentition and during the passage from primary dentition to mixed dentition among a group of Turkish children

To determine the changes in the molar and canine relationships in transition from the primary to the mixed dentition in 98 subjects selected among Turkish children living in the Erzurum city centre. This study is based on a 3-year follow-up of 98 children (46 girls, 52 boys) between the ages of 4 and 6years at the start of the study. The survey focused on the investigation of the changes that appeared in the occlusal relationships in the primary dentition and in the transition to the mixed dentition according to gender and age. The findings indicated that 73.6% of the 98 cases evaluated in the primary dentition developed a Class I molar relationship, and 26.4% developed a Class II molar relationship. As 64.3% FTP, 22.4% DS, and 13.3% MS molar occlusal relationships were evaluated at baseline; 22.4% FTP, 11.2% DS, and 66.3% MS molar occlusal relationships were evaluated at the end of the third year. While 75.5% Class I, 11.2% Class II, and 13.3% Class III primary canine occlusal relationships were evaluated at baseline; 53.1% Class I, 5.1% Class II, and 41.8% Class III primary canine occlusal relationships were evaluated at the end of the third year. With increased age, a statistically significant difference (p<0.001) was found in flush terminal plane, mesial step, and primary canine occlusal relationships and no statistically significant difference (p>0.05) was found in distal step relationships. Malocclusions observed in the primary dentition are signs of malocclusions in the permanent dentition.

Stability of molar relationship after non-extraction Class II malocclusion treatment

This study aimed to evaluate the stability of molar relationship after non-extraction treatment of Class II malocclusion. The sample comprised 39 subjects (16 females, 23 males) with initial Class II malocclusion treated with no extractions, using fixed appliances. Mean age at the beginning of treatment was 12.94 years, at the end of treatment was 15.14 years and at post-retention stage was 21.18 years. Mean treatment time was 2.19 years and mean time of post-treatment evaluation was 6.12 years. To verify the influence of the severity of initial Class II molar relationship in stability of molar relationship, the sample was divided into two groups, one presenting a ½-cusp or ¾-cusp Class II molar relationship, and the other with full-cusp Class II molar relationship. In dental casts from initial, final and post-retention stages, molar, first and second premolars and canine relationships were measured. Data obtained were analyzed by dependent ANOVA, Tukey and Pearson's correlation tests, as well as independent t test between the two groups divided by severity of initial molar relationship. There was a non-statistically significant 0.12-mm relapse of molar relationship. The initial severity of Class II molar relationship was not correlated to relapse in the post-retention period. When compared, the two groups showed no difference in relapse of molar relationship. It was concluded that correction of Class II molar relationship is stable and initial severity does not influence relapse of molar relationship.

A cephalometric comparison of horizontal and vertical skeletal parameters in North and South Indian population groups

A cephalometric study was carried out to compare skeletal parameters between North Indian (Group A) and South Indian (Group B) population. Sixty subjects in the age group of 16–21 years with acceptable profile, class I molar and canine relationship were selected. Cephalometric records were obtained for both the groups (A&B) and digitized. SNA, SNB, Wits appraisal (AO-BO), Mandibular Base (Go-Pog), Maxillary Base (PNS-Point A), Effective Mandibular Length (Co-Gn) and Mid-Facial Length (Co-Point A) readings were assessed to determine any difference in horizontal parameters. Similarly, Y-axis, Mandibular Plane Angle (MPA), Mandible to Cranial Base (FMA), Gonial Angle (GA), Upper and Lower Gonial Angle of Jarabak (UGA & LGA), Total Facial Height (TFH), Upper anterior Facial height (UAFH), lower anterior facial height (LAFH), Posterior Height/Total Anterior Height Ratio (PH/TAH) were digitized to find any difference in vertical parameters. Statistical analysis using paired t-test was done with level of significance less than 5%. Results showed that, South Indian girls had more MPA and FMA compared to the North Indians suggesting a tendency towards vertical growth pattern. This cephalometric appraisal study shall enable an orthodontist in formulating an optimal treatment plan for the two population groups.

Evaluation of the Occlusion and Arch Dimensions in the Primary Dentition of an Iranian Population

Introduction: The objective of this study was to gather information about normal occlusion and arch dimensions in the primary teeth of the children belonging to an Iranian population. Methods: This descriptive cross-sectional study was performed on 68 children from the city of Mashhad in the 3-5 age range. Dental arch dimensions, interrelationships of primary canine and second molars, overbite and overjet were evaluated. Results: Primate space was observed on both sides of the arch in 82.2% of the subjects. The most prevalent type of primary molar relationship was flush terminal plane (52.1%) followed by distal step (31.3%) and then mesial step (16.7%). The primary canine relationship was ranked in the descending order of prevalence as Class I (77.1%), Class II (13.5%), end-to-end (5.2%) and Class III (4.2%). Normal overbite and normal overjet was observed in 50% and 81.3% of cases, respectively. Conclusion: This study provides an insight into the dental arch dimensions, occlusion, spacing and crowding in primary dentition in Iranian children. In most of the cases, primate space and flush terminal plane were observed.

Prevalence of malocclusion in urban libyan preschool children.

Objectives:This cross-sectional observational study aimed at quantifying primary dentition parameters and exploring differences in those parameters between included age groups.Materials and Methods:The examined sample comprised 800 preschool children, 3- to 5-year-old in Benghazi city, of which 500 fulfilled the inclusion criteria. Primary canine relationship, spacing/crowding, overjet (OJ) and overbite (OB), occlusal relationship was carried out using Federation Dentaire Internationale (1973), modified to the primary dentition.Results:The prevalence of bilateral Class I, Class II, and Class III canine relationship was 69.6%, 22.4%, and 4.4%, respectively. The prevalence of asymmetric canine relationship was 3.6% with no significant difference between gender and age groups. Spacing, closed dentition, and crowding were observed in: 81.6%, 13,4% and 5% respectively in the upper arch, and 58.5%, 24.8%, and 16.7% correspondently in the lower arch. OJ and OB ranging between 1 and 3 mm were found in 82.6% and 56.5%, respectively. An OJ and OB of >3 mm was observed in 11.4% and 35%, respectively, and of edge to edge incisal relationship anteroposteriorly and vertically in 4.6% and 6% in this order. Anterior crossbite and anterior openbite were noted in 1.4% and 2.6%, respectively. There was no significant correlation between OJ and OB and age (P≥0.241). Additionally, there was no significant sex difference in the value of OJ (P=0.561). But, the mean OB value in boys was significantly greater than in girls.Conclusions:The current findings provide an insight into the prevalence of occlusal traits in urban Libyan preschool children and highlight the significance of early detection of malocclusion to assist in achieving effective and individualized long-term treatment planning.

Miniscrew-assisted mandibular molar distalization in a patient with skeletal class-III malocclusion: A clinical case report

In nongrowing patients with mild skeletal Class-III malocclusion, premolar extraction or molar distalization in the lower arch can be done as a part of camouflage treatment. Temporary anchorage devices are widely used for this purpose because they do not produce undesirable reciprocal effects and do not depend on the patient's cooperation. However, most reported cases in this regard have used interradicular miniscrews in the mandibular arch and these have a risk of failure as they can loosen due to collision with adjacent roots. This article showcases mandibular molar distalization utilizing miniscrews, inserted at the retromolar area to correct a Class-III problem. A 24-year-old girl with a mild skeletal Class-III malocclusion and dental Class-III molar and canine relationship bilaterally was referred for orthodontic treatment. The treatment plan included distalization of the lower molars bilaterally followed by full fixed appliance therapy, after third molar extractions. For the lower molar distalization, the miniscrews were inserted at the retromolar pad. At the end of 21 months, a Class-I molar and canine relationship, normal overjet and overbite were obtained. The average amount of distalization of mandibular first molar was 3.2 mm at the crown level. In conclusion, placing miniscrews at the retromolar pad area for lower molar distalization was found to be a simple and effective method for correcting anterior cross bite and mandibular anterior crowding or protrusion, without the need for patient compliance.

The relationship of maxillary canines to the facial anatomical landmarks in a group of Thai people

PURPOSEThe objective was to evaluate canine positions, intercanine tip width (ICTW) and width of distal surface of canine (WDC), related to facial landmarks including interalar width (IAW), intercommissural width (ICoW), and distance between left and right projection lines drawn from inner canthus of eyes to alae of the nose (DPICa) in a group of Thai.MATERIALS AND METHODSOne hundred Thai subjects aged 18-35 years were selected. IAW and ICoW were measured on subject's face using digital vernier caliper. Irreversible hydrocolloid impression of the upper arch was taken, and a cast was poured with dental stone. Silicone impression material was used to take imprint of the incisal edge of upper six anterior teeth. DPICa was obtained from the subject's face using custom-made measuring equipment and marked on the silicone incisal imprint. The marks were then transferred from the imprint to the stone cast and measured with digital caliper. The ICTW and WDC were also measured on the stone cast. Pearson's correlation was used to determine the correlation.RESULTSThe results revealed that the correlation between ICTW-ICoW was 0.429 and ICTW-DPICa was 0.573. The correlation between WDC-ICoW was 0.426 and WDC-DPICa was 0.547. However, IAW did not show any correlation with ICTW or WDC (P>.05).CONCLUSIONThe correlation between canine position and facial landmarks was found. ICTW and WDC had relationship with ICoW and DPICa. DPICa showed stronger correlation with the position of maxillary canine than that of ICoW.

Unilateral maxillary molar distalization with zygoma-gear appliance

The aim of this study was to present the orthodontic treatment of a 15-year-old boy with a unilateral maxillary molar distalization system, called the zygoma-gear appliance. It consisted of a zygomatic anchorage miniplate, an inner bow, and a Sentalloy closed coil spring (GAC International, Bohemia, NY). A distalizing force of 350 g was used during the distalization period. The unilateral Class II malocclusion was corrected in 5 months with the zygoma-gear appliance. The maxillary left first molar showed distalization of 4 mm with an inclination of 3°. The maxillary premolars moved distally with the help of the transseptal fibers. In addition, there were slight decreases in overjet (-0.5 mm) and maxillary incisor inclination (-1°), indicating no anchorage loss from the zygoma-gear appliance. Preadjusted fixed appliances (0.022 × 0.028-in, MBT system; 3M Unitek, Monrovia, Calif) were placed in both arches to achieve leveling and alignment. After 14 months of unilateral distalization with the zygoma-gear appliance and fixed appliances, Class I molar and canine relationships were established with satisfactory interdigitation of the posterior teeth. Acceptable overjet and overbite were also achieved. This article shows that this new system, the zygoma-gear appliance, can be used for unilateral maxillary molar distalization without anchorage loss.

The prevalence of root resorption of maxillary incisors caused by impacted maxillary canines

The aim of this study was to evaluate the prevalence of root resorption of maxillary incisors caused by impacted maxillary canines using low-dose dental computed tomography and to gain additional knowledge of the underlying aetiology and the progression of root resorption. A total of 440 patients (mean age, 24.7 years) with 557 impacted maxillary canines were examined regarding their location and the occurrence of root resorption of maxillary incisors. The frequency of root resorption was 2 % of central and 7.7 % of lateral maxillary incisors. The location of the 557 impacted canines within the dental arch was palatal in 67.5 %, buccal in 15.4 % and central in 17.1 %. No significant differences could be shown with respect to the width and the shape of the dental follicle of the impacted maxillary canines and the presence of root resorption of incisors. The presence of root resorption of central (p < 0.0001) and lateral (p < 0.023) maxillary incisors was significantly correlated with an existing contact relationship of the impacted maxillary canines. Our investigation confirms the theory of prior reports comprising a much larger patient population, hypothesising that the dental follicle of impacted maxillary canines does not cause resorption of adjacent maxillary incisors per se. Root resorption of maxillary incisors is correlated with effects of contact of the impacted maxillary canines, and these findings should be considered in treatment planning. Our findings are consistent with other reports and may develop new treatment approaches for the treatment of this sequela.