Type Of Malocclusion Research Articles

Therapeutic effect analysis of skeletal class Ⅲ malocclusion treatment by transmission straight wire technique

This study aimed to investigate the therapeutic effects and advantages of skeletal class Ⅲ malocclusion treatment by transmission straight wire technique. Ninety-seven patients who receivedtreatmentfor skeletal class Ⅲ malocclusion atthe Department of Stomatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2012 to January 2017 were selected for this retrospective study. All these patients refused surgery. They were divided into two groups in accordance with the type of skeletal malocclusion: mild-to-moderate skeletal malocclusion group (-4°≤ANB <0°) and severe skeletal malocclusion group (-8°≤ANB<-4°). Each of the two groups was divided further into two small groups in accordance with the technique used: T group (transmission straight wire technique) and M group (MBT technique). The crossbite of all 59 patients in the mild-to-moderate skeletal malocclusion group was successfully treated. The molars were classified as classⅠrelationship, and the facial profile improved. Significant differences were found in the values of U1/SN angle, L1/MP angle, and Lip-Diff between the T and M groups before and after the treatment (P<0.05). The extent of incisor root resorption was lighter in the T group than in the M group (P<0.05). In the severe skeletal malocclusion group, the crossbite of all 38 patients was cured or partially cured. Fourteen patients showed severe lower anterior teethinclination (five in the T group and nine in the M group), and the profiles did not significantly improve. Significant differences were observed in the values of U1-NA value, U1/SN angle, L1-NB value, L1/MP angle, LLP, and Lip-Diff between the T and M groups before and after the treatment (P<0.05). The extent of incisor root resorption was lighter in the T group than in the M group (P<0.05). Relative to the MBT technique, the transmission straight wire technique has great advantages in improving facial profile, reducing the compensatory inclination of the upper and lower anterior teeth, and reducing the risk of root resorption in the treatment of skeletal class Ⅲ malocclusion.

Evaluation of the correlation between impacted canine and malocclusions

Abstract Introduction: Tooth impaction is defined as the absence of a tooth on the arch, after its normal eruption age. The main reason canines are impacted is the lack of space required for the tooth to erupt. Aim of study: The main objective of this study is to determine the types of malocclusions associated with canine impaction (Lindauer classification). A secondary objective is to establish the correlation between these parameters and identification of subjects with high risk of canine impaction based on pre-existing malocclusion. Material and methods: This study was performed on a sample of 20 patients, 9 men and 11 women. The dental casts were subject to Angle classification and various measurements such as arch perimeter, Pont’s index, sum of the mesiodistal width of the incisor and arch length were performed. The Lindauer sectorial classification was determined based on the patients’ panoramic radiography. Results: According to the data collected, the Class II /2 malocclusion is more frequent, and it is associated with the impacted canine (approximately 50%). According to the Lindauer classification higher frequency of the impacted canines was found in Sector IV. Conclusion: The diagnosis for impacted canines is often associated with Class II /2 malocclusion, and according to the Sector classification, it is often localised in Sector IV.

Outcomes of orthodontic treatment performed by individual orthodontists vs 2 orthodontists collaborating on treatment

One factor that can affect treatment outcomes is the treatment provider, and this factor has not been extensively studied. This research aimed to evaluate orthodontic treatment quality, length, and efficiency when 2 orthodontists collaborated on treatment, compared with the treatment provided solely by either orthodontist. A total of 150 consecutively treated subjects were divided into 3 equal groups based on the treating clinician. Patients in group A were treated by orthodontist A, group B by orthodontist B, and group C by both orthodontists in collaboration. The Peer Assessment Rating (PAR), Index of Complexity, Outcome, and Need (ICON), American Board of Orthodontics-Discrepancy Index, and American Board of Orthodontics-Cast and Radiographic Evaluation were used to assess the pretreatment and posttreatment status. Patient age, gender, type of malocclusion, extraction treatment, orthognathic surgery, treatment length, number of visits, and treatment efficiency index were assessed. Posttreatment PAR and ICON indices showed excellent results in all 3 groups. American Board of Orthodontics-Cast and Radiographic Evaluation was significantly higher in group C (25.3 points) than in group A (21.5 points) or group B (22.0 points) (P=0.014). Patients in group A had significantly shorter treatment time (23months) than those in either group B or C (26months) (P=0.011). Patients in group C required more appointments (27 visits) than those in either group A or B (23 and 25 visits, respectively). The treatment efficiency index showed no statistically significant difference among the 3 groups. There was no difference in treatment quality among the 3 groups, as assessed by the PAR index and ICON. Jointly treated cases required 2 to 4 more visits and had higher American Board of Orthodontics-Cast and Radiograph Evaluation scores than those treated by either orthodontist. Complex cases required 6 to 7 more months when they were treated collaboratively.

Estimation of the prevalence of malocclusion on the basis of nationwide oral health examinations of pre-adolescent and adolescent students during 2012-2017.

ObjectiveTo investigate the prevalence of malocclusion with respect to grade, sex, and year among Korean pre-adolescent and adolescent students during 2012–2017.MethodsA total of 165,996 students (first grade [E1, 6–7 years of age], fourth grade [E4, 9–10 years], seventh grade [M1, 12–13 years], and tenth grade [H1, 15–16 years]) were selected by stratified sampling method and underwent the nationwide oral health examination performed by the Ministry of Education, Republic of Korea. The malocclusion assessments based on dentists’ judgments were “no malocclusion,” “needs orthodontic treatment (N-OTx),” and “under orthodontic treatment (U-OTx).” The sum of N-OTx and U-OTx cases was determined as the number of students with malocclusion. After analyzing the prevalence of malocclusion according to grade, sex, and year-by-year differences, Pearson correlation analyses and two-way analyses of variance were performed.ResultsThe prevalence of malocclusion was 18.7%, which increased with the grades (E1 [8.3%] < E4 [15.8%] < M1 [22.9%] < H1 [25.3%], p < 0.001). However, there was no significant difference in the prevalence of malocclusion in each grade group for the period (p > 0.05) without significant correlation (E1, ρ = 0.129; E4, ρ = –0.495; M1, ρ = 0.406; H1, ρ = –0.383; all p > 0.05). The prevalence of malocclusion within each grade group over the six-year period was more prominent in the female (p < 0.0001).ConclusionsFurther studies are necessary to modify the malocclusion assessment method to account for specific types of malocclusion in pre-adolescent and adolescent students.

Evaluation of stylohyoid complex in subjects with different types of malocclusions using cone-beam computed tomography: a retrospective study in a Turkish subpopulation.

According to the functional matrix theory, the development of maxillomandibular complex may be affected by the surrounding tissues. The aim of this study was to evaluate the length and angulation of the styloid process in different types of malocclusions using cone-beam computed tomography (CBCT). Angulations and length of the styloid process were evaluated in CBCT images of 97 individuals retrospectively. The patients were classified as class I, II, and III groups according to sagittal skeletal classes. The mean length, anterior angulation, and medial angulation of the styloid process were analyzed. Statistical significance was evaluated at p < 0.05. The mean styloid process length in group class III was found to be significantly longer than class I (p: 0.035). Anterior angle was significantly higher in class III group than in other groups (p < 0.05). No statistically significant difference was found in medial angle between the groups (p: 0.506). According to present findings, class III malocclusion is associated with the stylohyoid complex morphology due to longer styloid process lengths and higher anterior angle values.

Prevalence of Caries and Associated Risk Factors in a Representative Group of Preschool Children from an Urban Area with High Income in Milan Province, Italy.

The present survey provides a quantitative assessment of caries prevalence, covering a group of 3–5 year-old children from an urban area generally with a high income in the province of Milan, and a comparison of the obtained results with the data presented by the W.H.O. A cross-sectional study was conducted in the period from March to September 2018 to investigate the prevalence of caries in a sample of 160 children (82 females and 78 males). The absence/presence of caries was defined as a dependent variable. Factors concerning lifestyle, diet, oral habits, oral hygiene, the presence and type of malocclusion and mouth breathing attitude were considered as risk factors. Data were analyzed by Chi-square (χ2) and regression tests using SPSS (version 25.0) software. In total, 84.38% of children (135 out of 160) showed no caries. A regression analysis demonstrated that children who had already received an early first dental visit were mostly those already affected by caries. Furthermore, children who had four meals daily or more were less exposed to the risk of developing caries compared to those who had only 1–3 meals daily. The caries prevalence of preschool children from urban areas with a high income in Milan province is relatively close to that considered acceptable by the W.H.O. in its proposed goals for the year 2020. Therefore, it can be concluded from the obtained results that there is a possibility for further improvement in preventing caries growth at its initial stage: it is necessary for the number of meals daily consumed by children to be controlled by parents, and conducting a dental visit early in childhood must not be neglected.

Correlation between Caries, Body Mass Index and Occlusion in an Italian Pediatric Patients Sample: A Transverse Observational Study.

Background: The aim of this study was to evaluate the correlation between caries, body mass index (BMI) and occlusion in a sample of pediatric patients. Methods: The study group included 127 patients (72 female, 55 male) aged between 6 and 16 years (mean age 10.2) and selected between January and June 2019 at the Department of Pediatric Dentistry, University of Messina. Caries incidence was evaluated using the decayed, missing and filled teeth (DMFT) index. On the basis of BMI values, using a table adjusted for age and gender, patients were grouped into four categories (underweight, normal weight, risk of overweight, overweight). Results: There was no significant correlation between BMI and DMFT in the whole sample. The study of the correlation between BMI and DMFT in patients with different types of malocclusion showed a significant inverse correlation for patients affected by II class and deepbite malocclusion. Conclusions: The incidence of caries does not seem to be significantly related to BMI and occlusal patterns, but it decreases with increasing age.

Effects of Rapid Palatal Expansion on Chewing Biomechanics in Children with Malocclusion: A Surface Electromyography Study.

Malocclusion during childhood may affect both morphology and masticatory function and could greatly affect the subsequent growth and development of the jaws and face. The purpose of this study was to evaluate the efficiency of surface electromyography in describing the effects of the rapid palatal expansion (RPE) on Masseter (M) and Temporalis Anterior (T) muscles’ activity in 53 children with different types of malocclusion: bilateral posterior crossbite (BPcb), underdeveloped maxillary complex without crossbite (NOcb) and unilateral posterior crossbite on the right (UPCBr) and on the left (UPCBl). The muscular activities during chewing tasks were assessed bilaterally before and after RPE application and three months after removal. Both the envelope’s peak (µV) and its occurrence (% of chewing task) were extracted from the surface electromyography signal. Our results showed the presence of statistically significant differences (p < 0.05) on temporomandibular joint muscles, across different assessments, in all the tested populations of subjects. Surface electromyography demonstrated a relationship between the correction of a maxillary transverse discrepancy and the restoration of a muscle’s activation patterns comparable to healthy subjects for both T and M.

Single Nucleotide Polymorphisms (SNPs) of COL1A1 and COL11A1 in Class II Skeletal Malocclusion of Ethnic Javanese Patient.

BackgroundThe prevalence of malocclusion cases in the orthodontic specialist clinic in Airlangga University’s Dental Hospital in Surabaya, Indonesia, in 2014–2016 is fairly high, as 55.34% of the occurrences were identified as class II skeletal malocclusion. This type of skeletal malocclusion, which is usually recognized in adults, occurs as a result of variation during growth and development. Lately, there have been many reports on gene polymorphisms of COL1A1 and COL11A1, which are assumed to be associated with class II skeletal malocclusion in Caucasians.PurposeThis study aims to analyze the relationship between single nucleotide polymorphisms (SNPs) of COL1A1 and COL11A1 with class II skeletal malocclusion in Javanese ethnic group patients with mandibular micrognathism.Materials and MethodsThe diagnosis of class II skeletal malocclusion was established using the lateral cephalometric radiographs (ANB angle ≥4°) (n=50). DNA was extracted from the patient’s peripheral blood. After that, PCR, electrophoresis, and DNA sequencing were conducted on the extracted DNA based on COL1A1 and COL11A1 primers.ResultsThe SNPs in COL1A1 are c.20980G/A in 27 patients and c.20980G>A in 8 patients, whereas SNPs in COL11A1 are both c.134373C/A and c.134555C/T in 8 patients and both c.[134373A>C] and c.134582G>A in 10 patients. All samples show the deletion (c.[134227delA]) in COL11A1.ConclusionSNPs in COL1A1 and COL11A1 have been found in class II skeletal malocclusion of Javanese ethnic group patients. Seventy percent of SNPs in COL1A1 occur in rs.2249492, whereas 36% of newly discovered SNPs appear in COL11A1. All samples also have deletion in COL11A1.

VERTICAL DIMENSION OF OCCLUSION CHARACTERISTICS IN PATIENTS WITH DIFFERENT TYPES OF MALOCCLUSIONS BY THE SHIMBASHI INDEX IN THE AGE ASPECT

Occlusal vertical dimension is one of the important parameters, which is significantly related to the functional status of the masticatory complex.&#x0D; The finding of the optimal occlusal vertical dimension and the method of its determining is a debatable and topical issue in planning of orthodontic correction and orthopedic rehabilitation.&#x0D; One of the morphometric methods of the occlusion vertical dimension (OVD) is the Shimbashi index or the LVI-index. The Shimbashi index allows us to count out the "perfect" occlusal vertical dimension due to the "golden proportion" principle based on the width of the upper center incisor.&#x0D; The purpose of the research was to verify the expediency of the Shimbashi index using while examinating orthodontic patients.&#x0D; The morphometric investigation of control-diagnostic models of jaws of 300 orthodontic patients in different ages was performed. All surveyed patients were divided into the age and the tooth row interrelation type in sagittal and vertical planes.&#x0D; In the age aspect, the smallest value of the occlusion vertical dimension is determined at the age of 8-9 years, which can be connected with incompleted stages of the bite elevation and morphofunctional formation of the masticatory complex. In the period from 8 to 11 years there is one significant increasing of the OVD, which, obviously, is connected with active growth of the alveolar processes and the realization of bite elevation stages. In the 14-15, 16-17 and 18-19 years, the OVD does not reach to the Shimbashi index value by 5 mm and it doesn’t increase more in the future.&#x0D; Among the sagittal malocclusions, the greatest vertical dimension of occlusion was observed in patients with III class of dentofacial abnormalities. This can be explained by the fact that the mesial bite is usually accompanied by an increase of vertical parameters. However, the interalveolar height was still less by 3 mm compared to the "ideal" one. In classes I and II of dentofacial abnormalities, OVD was almost the same – 13.55 ± 2.55 mm and 13.56 ± 2.55 mm, which is in average by 5 mm less (p˃0.05) than calculated one by the Shimbashi index.&#x0D; While dividing patients by the depth of the incisal overlap, we obtained quite logical results. In particular, the lowest occlusion vertical dimension was found in patients with increased depth of the incisal overlap. The most interesting is the fact that even in patients with a depth of incisor overlap less than 1/3 of the crowns of lower incisors, that is a tendency for open bite, the vertical dimension of occlusion was still less than measurement found by the Shimbashi index, although the difference between them was minimal (approximately 1,5 mm) compared to other two study groups.&#x0D; According to the results of the study, all types of malocclusions are characterized by decrease of the occlusion vertical dimension refers to the Shimbashi index. The obtained data suggest the next idea: either the occlusal vertical dimension calculated by Shimbashi index is a bit exaggerated and needs clarification, in particular by the investigation of skeletal parameters according to the skull X-ray, or, indeed, modern orthodontic patients have a total reduction of the interalveolar height.

Facial soft tissue thickness in Yangtze River delta Han population: Accurate assessment and comparative analysis utilizing Cone-Beam CT.

Facial approximation plays a vital role in personal identification when other methods cannot be applied, and the study on facial soft tissue thickness (FSTT) is important to allow more accurate facial approximation. The Cone-Beam CT (CBCT) is considered to be an accurate approach in assessing FSTT, however only few studies have assessed the FSTT norms by CBCT in Chinese populations. The aim of this study was to (1) establish forensic measurement approach on a 3D model reconstructed by CBCT image; (2) obtain FSTT norms from the adults of Yangtze River delta Han population; (3) determine the impacts of sex, age, BMI as well as malocclusion type on FSTT and (4) form a FSTT database through CBCT. A total of 60 facial landmarks were primarily established from 3D reconstructed models from CBCT images of 424 healthy Han adults (130 males and 294 females) aged from 21 to 50years in Yangtze River delta region and measurements were carried out. The multivariate analysis of variance test and multiple linear regressions test showed that the FSTT values on most landmarks were significantly different between sexes and BMI, and males showed greater values, expect for the landmarks distributed in malarzygomatic areas. Simultaneously, BMI mostly affected the landmarks located in zygomatic region. Besides, only a few landmarks were influenced by age. Interestingly, several periodontal landmarks were influenced by malocclusion types, thus the impact of malocclusion types on FSTT requires attention. Finally, the validation analysis suggested that measurement approach is an important factor for FSTT.

PREVALENCE OF MALOCCLUSION AMONG YEMENI CHILDREN OF PRIMARY SCHOOLS

Objective: Malocclusion is every difference in the arrangement of teeth beyond the standard of regular occlusion illustrated by anomalies within the dental arches. The purpose of this study was to measure prevalence of malocclusion between primary school children in Sana’a city Yemen.&#x0D; Methods: A cross sectional study was conducted on 1079 school children (546 girls and 533 boys), their age ranged from 7 to 12 years old from public and private schools selected randomly in Sana'a City, Yemen. The prevalence of malocclusion was investigated according to age, gender and school type based on Angle's classification.&#x0D; Results: The study showed that the overall prevalence of malocclusion among school children was 81.1%, in which Class I normal molar association was found only in 18.9% of school children, while Class I malocclusion included the highest percentage of the sample 70.4%, followed by Class II relation 9.5%, and Class III involved only 1.1%. The most prevalent malocclusion trait was spacing 35.7%, whereas the crowding was present in 30.0% of the sample. The deep bite was present in 10.1% followed by anterior crossbite 8.8%, midline diastema 8.6%, anterior open bite 4.5%, posterior crossbite 4.0%, and the least noted malocclusion trait was posterior open bite 0.4%.&#x0D; Conclusion: In conclusion, there was a high rate of malocclusion in school children and significantly increased with age, class I malocclusion was the most common followed by Class II malocclusion, while Class III was the rear. The most prevalent occlusal problem was spacing, followed by crowding. Thus, 7-12 year-olds can benefit from interceptive and preventive oral health procedures which may either entirely prevent or reduce the development of serious types of malocclusions afterward in their lives.&#x0D; Peer Review History: &#x0D; Received 8 January 2020; Revised 9 February; Accepted 1 March, Available online 15 March 2020&#x0D; UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency.&#x0D; Received file &#x0D; &#x0D; Average Peer review marks at initial stage: 6.5/10&#x0D; Average Peer review marks at publication stage: 8.5/10&#x0D; Reviewer(s) detail:&#x0D; Name: Dr. George Zhu&#x0D; Affiliation: Tehran University of Medical Sciences, Tehran, Iran&#x0D; E-mail: sansan4240732@163.com&#x0D; &#x0D; Name: Dr. Gehan Fawzy Abdel Raoof Kandeel&#x0D; Affiliation: Pharmacognosy Department, National Research Centre, Dokki, 12622, Giza, Egypt&#x0D; E-mail: gehankandeel9@yahoo.com&#x0D; Comments of reviewer(s): &#x0D; &#x0D; Similar Articles:&#x0D; COCCIDIAN INTESTINAL PARASITES AMONG CHILDREN IN AL-TORBAH CITY IN YEMEN: IN COUNTRY WITH HIGH INCIDENCE OF MALNUTRITION&#x0D; EVALUATION OF THE IMMUNE RESPONSE TO POLIO VACCINE IN MALNOURISHED CHILDREN IN SANA'A CITY&#x0D; PREVALENCE AND POTENTIAL RISK FACTORS OF HEPATITIS B VIRUS IN A SAMPLE OF CHILDREN IN TWO SELECTED AREAS IN YEMEN

Genetics of malocclusion: A review

Malocclusion is one of the most common craniofacial problems observed worldwide. Affected individuals suffer not only from aesthetic concerns but also from functional problems, such as with mastication and pronunciation. The prevalence of malocclusion in East Asians is higher than in other races. Reports have shown besides environmental factors, there is association between certain types of malocclusion with specific genes. Positive association of mandibular prognathism has been implicated to genes such as Matrilin-1; while mutation in DUSP6 has also been shown to contribute to the incidence of malocclusion. This review aimed to briefly discuss the involvement of other additional genes such as MYO1H and PAX9 in the incidence of malocclusion as observed from our local institution.

The Relation between Adermatoglyphics and Dental Malocclusions of Iraqi Adults

Background: Dermatoglyphics is studying the surfaces of the hands and feet for epidermal ridges. Orodental patterns developed emberiologically at the same time. Various types of malocclusion have genetic predisposition affected environmentally. These malocclusions usually accompanied by various dermal patterns which are specific for each class. Aims of the Study: To compare the dermatologyphics characteristic of patients with various classes of malocclusions. Methodology: The patients were divided into four groups: Group 1: class I, group 2: class II Div 1, group 3: class II Div 2, Group 4: class III malocclusion. The finger and palmar prints were recorded and analyzed for each type of pattern. Results and Conclusion: The class II Div 2 pattern was correlated with higher frequency of whorls, while in class III, there was increased appearance of arches and radial loops with decreased incidence of ulnar loops.

Facial Analysis and Malocclusion of Children Attending a Dental School Clinic

To characterize the face and the malocclusion type of children treated at a dental school. Materials and Methods: Retrospective analysis of clinical data with orofacial measurements....

The Effect of First Permanent Tooth Eruption on Dental Arch Dimension

Background: Crowding is one of the most prevalent types of malocclusion as well as a major problem in clinical orthodontics. It is essential to know the cause of crowding in order to achieve a better treatment. Objectives: A longitudinal analysis of arch dimension changes in late primary and early mixed dentition periods in children was designed and investigated the effect of eruption of precedence on the arch size in the samples under study. Methods: This longitudinal study was carried out on 32 children aged 5.5 - 6.5 years who had no erupted permanent dentition. Impression was taken and the arch perimeter, depth and width as well as tooth size were measured by a digital calliper and a brass wire on casts. After eruption of the first permanent tooth, the second impression was taken; the above-mentioned parameters were measured on the second casts. Data were analysed by ANOVA test. Results: Four pattern of eruption of precedence were as follows: maxillary 1st molar, mandibular incisors, Mandibular 1st molars and simultaneous eruption of maxillary and mandibular 1st molars. With eruption of mandibular central incisors, inter canine width and overjet increased by 0.81 and 0.27 mm, respectively. The mandibular arch perimeter increased by 2.25 mm with simultaneous eruption of maxillary and mandibular permanent first molars. The maxillary arch perimeter increased by 1.25 mm and 1.50 mm with eruption of maxillary first molars and simultaneous eruption of maxillary permanent first molars, respectively. Conclusions: Eruption precedence had a significant effect on changing mandibular inter canine width, maxillary arch perimeter, mandibular arch perimeter and overjet.

Quantitative analysis of gingival phenotype in different types of malocclusion in the anterior esthetic zone.

Background:For any esthetic treatment planning, the shape and form of gingiva should be a prime factor of concern. The correct identification of gingival phenotype (GP) ensures a firm foundation for future health and prognosis of the treatment indicated. Hence, the aim of the present study was to evaluate the correlation between the GP in the anterior esthetic zone with different types of maloclussion and severity of crowding.Materials and Methods:A total of 110 periodontally healthy controls were equally divided into two groups depending on the type of malocclusion. They were further divided according to the levels of dental crowding as mild, moderate, and severe. GP was measured on the anterior esthetic teeth using transgingival probing, and width of the attached gingiva (WAG) was measured using histochemical staining method.Results:In severe crowding group, the GP in 12 and 22 region was found to be thick (P = 0.035) while, in 32 and 42 region was thin (P = 0.042). The WAG shows a significant difference between WAG with 23 in severe crowding group with P = 0.042, whereas there was no significant relationship found between the GP with Angle's classification.Conclusion:Within the limitations of the study, it can be concluded that the teeth in the maxillary and mandibular anterior esthetic region showed the thin phenotype. When the severity of crowding increases, the GP and WAG vary depending on the position of the tooth. There is no association between the Angle's classification and the mean GP of the maxillary and mandibular anterior region teeth.

Dental Arch Crowding in Permanent Dentition Among Class I And Class Ii Div 1 Malocclusion

Crowding of dental arches is a common malocclusion and it involves improper alignment of the anterior or posterior teeth. The primary objective of the study was to evaluate the severity of crowding in subjects with Class I and Class II malocclusions. This retrospective study was performed using case records of subjects visiting a private dental college. The present study included 200 subjects with equal distribution of class I and class II malocclusions. Data on type of malocclusion and other associated factors was recorded and tabulated. Analysis of the data was performed using SPSS, descriptive statistics and Chi square tests were done. The study reported 53% mild crowding, 31% severe crowding and 16% moderate crowding in class 1 malocclusion whereas in Class II division 1 malocclusion 50% severe crowding, 46% mild crowding, 4% moderate crowding was observed. Within the limits of the present study, it can be concluded mild crowding was more prevalent followed by severe and moderate crowding in class I malocclusion whereas in Class II division 1 malocclusion severe crowding was more common followed by mild and moderate crowding. No significant association between the type of malocclusion and the severity of crowding was noted.

Impaction of mandibular third molars after orthodontic treatment by the edgewise method: a retrospective study.

This study aimed to determine the incidence of mandibular third molar (M3) impaction after orthodontic treatment by edgewise appliances, and identify possible determinant factors of M3 impaction. A retrospective cohort study was conducted with 1154 patients. Complete orthodontic records were analyzed pretreatment and posttreatment, considering the following variables: type of Angle malocclusion, treatment with or without extraction of first premolars, overbite, stage of dentition, M3 prior angulation and duration of orthodontic treatment. Impaction was determined after radiographic evidence of total closure of the root apex. The chi-square test and Poisson regression (p < 0.05) were used for statistical analysis with a hierarchical approach. Rate ratios (RR) and 95% confidence intervals (CI) were calculated. Mandibular M3 impaction incidence was 17%. Overbite equal to or greater than 4 mm (RR = 1.23, 95%CI: 1.11-1.26, p < 0.001), prior mesial angulation of M3 (RR = 0.59, 95%CI: 0.52-0.68, p < 0.001), non-extraction of first premolars (RR=1.06, 95%CI: 1.01-1.12, P=0.019) and orthodontic treatment time equal to or less than three years (RR = 0.94. 95%CI: 0.90-0.99, p < 0.014) were significantly associated with impacted M3. There was no correlation between the type of Angle malocclusion and the risk of impaction. In conclusion, the incidence of mandibular M3 impaction was considered low. The main pretreatment factors directly involved in impaction were mesioangulation of M3 and overbite equal to or greater than 4 mm. Orthodontic treatment with extraction of first premolars and treatment time greater than 3 years reduce the risk of impaction.

Prevalence of Chronic Gingivitis in Adolescents with Moderate Crowding of Dental Arches

Dental crowding makes it challenging to maintain oral hygiene brushing since there is food debris accumulation in the interdental area which cannot be removed by regular brushing leading to plaque and calculus formation that in turn causes gingivitis and dental caries. The aim of this study was to evaluate the prevalence of gingivitis in the adolescent population with moderate crowding of the dental arches visiting a private dental hospital. This retrospective study was conducted using records of patients visiting a private dental college from June 2019 to April 2020. The study population included adolescent patients with crowding of dental arches, selected by non-probability purposive sampling. Data was collected, tabulated and then subjected to statistical analysis. Chi-square tests were performed. Out of 1926 patients aged between 15-18 years, 110 patients reported with moderate crowding of the dental arches. There was no significant association between age and gingivitis, gender and gingivitis and malocclusion and gingivitis. Gingivitis was commonly seen in subjects with Class I malocclusion. The prevalence rate of gingivitis was 72.2% in patients with moderate crowding. The prevalence of moderate crowding was 2% in the entire population and there was no association of moderate crowding with age, gender or type of malocclusion