Tooth Size Discrepancy Research Articles

Successful completion of orthodontic therapy in a patient with osteopetrosis: Case Report.

Orthodontic therapy in patients with osteopetrosis (OP) of the jaws has typically been contraindicated owing to the presence of poorly perfused and extremely compact bone, and the potential risk for infection and osteomyelitis. As such, completed orthodontic cases in association with OP have rarely been published. A patient aged 14 years 6 months, with no known diagnosis of OP, sought orthodontic assessment for anterior crowding. The patient exhibited a straight facial profile and increased mandibular facial height, competent lips, shallow mentolabial sulcus with mild mentalis strain, flat/reverse smile arc and wide buccal corridors on smiling. The patient had a Class I incisor relationship on Class I skeletal bases with bilateral Class I molars and Class II canine relationships. This was complicated by a crossbite involving the lateral incisors and a Bolton discrepancy due to small maxillary lateral incisors. A radiologic assessment revealed polyostotic OP of the oromaxillofacial complex. Treatment consisted of maxillary and mandibular fixed orthodontic therapy, bite turbos and elastics to level and align the dentition. Extractions of permanent teeth were not needed. At the conclusion of treatment, there was a slight left Class II malocclusion, with incomplete intercuspation on the left side due to tooth size discrepancy, possibly attributed to inadequate elastics compliance and the presence of osteopetrotic bone. The treatment was completed in 3 years, 1 year longer than anticipated. This report represents the second published account of a patient with OP successfully managed with comprehensive orthodontic care and without osseous complications. Obtaining cephalometric measurements on OP-affected patients may be imprecise owing to the presence of extremely dense bone and difficulty to identify bony landmarks. To reduce osteopetrotic sequelae, attending clinicians should consider reduced exertional orthodontic forces and closely monitor patients for adverse alveolar events.

Interproximal reduction in orthodontics: Reported practices and perceptions of orthodontists in the Republic of Ireland

Objectives To ascertain reported practices and perceptions of orthodontists regarding interproximal reduction (IPR) in the Republic of Ireland (RoI). Method Questionnaires were administered to orthodontists in the RoI, seeking their demographics, reported IPR practices and related perceptions. Results Questionnaire responses were received from 105 (75%) of those invited to participate. Nearly all (98%) performed IPR, with 44% reporting increased recent use. Lower labial segment teeth were most frequently reduced in adults or adolescents to reshape teeth, resolve mild crowding or address tooth size discrepancies. This was in conjunction with aligner (59%) or fixed appliance (33%) treatments. Removal of 2-4mm of enamel per arch was most common (60%). The majority (82%) performed IPR over several visits with handheld strips, (87%) or strips in holders (58%), or with diamond burs in an air rotor (51%). Orthodontists perceived their patients to be unfamiliar with IPR, to find it uncomfortable (48%) rather than painful (9%) and preferable to extraction (71%). Conclusions Conservative IPR of less than 4mm per arch was mostly undertaken for teeth in the lower labial segment in adults or adolescents in conjunction with aligner or fixed appliance treatments. Handheld strips were most commonly used. Orthodontists perceived their patients to be unfamiliar with IPR, to find it uncomfortable rather than painful and preferable to extraction.

Comparative Study of Mesiodistal Crown Dimensions and Tooth Size Discrepancies of Thalassemia and Control Iraqi Patients

Aims: To find differences in mesiodistal tooth width in Iraqi B thalassemia compared with normal individuals. Setting and design: 44 subjects, 22 thalassemia (11 males, 11 females) (12.5–22) years, and 22 control (11 males, 11 females) 14–23 years. Methods and Material: Registrations of MD for maxillary and mandibular teeth from the first molar on one side to analogous tooth on the other side were done. Statistical analysis: Mean, standard deviation and 2-sampled t-test were used. Results: In both groups, males’ crown size was greater than females. In the study group largest gender variances appear in the maxillary molars, mandibular molar, maxillary central and maxillary canine respectively. In control, the greatest sexual difference is present in the maxillary first premolar followed by the mandibular second premolar. The means of mesiodistal in both sexes in thalassemia were smaller than in control except in male maxillary central and lateral and female maxillary lateral incisor. In the maxilla, a significant decrease in mesiodistal thalassemia is present in canine and second premolar in both sexes. In the mandible, a significant decrease in thalassemia was present in all comparisons in both genders in comparison with the control. The greatest mesiodistal difference in the mandibular male is present in the first molar, first premolar, second premolar, canine, lateral and central incisor respectively. In female mandibular teeth, the greatest difference is present in the first molar followed by the first premolar, second premolar, canine, lateral incisor and central incisor. Conclusions: Means mesiodistal dimensions in thalassemia show a significant reduction in mandibular teeth and maxillary canine and second premolar in both genders.

The Role of Interproximal Reduction (IPR) in Clear Aligner Therapy: A Critical Analysis of Indications, Techniques, and Outcomes.

Interproximal reduction (IPR) has become a standard practice in orthodontic treatment, particularly in the clear aligner therapy. It became an integral part of the digital plan when using clear aligners. Given the irreversible nature of IPR, precise planning and performance is essential. This article aims to analyze and summarize the existing literature on IPR in the context of clear aligners. The goal is to help clinicians to gain essential knowledge for safely and effectively navigating IPR. The review critically examines different perspectives found in the literature, covering indications, methods, and outcomes. Topics exploring the impact of IPR on treatment outcomes include space gaining, addressing tooth size discrepancies, tooth shape adjustments, resolving malocclusion, and enhancing aesthetics. Emphasizingprecision of the procedure by the clinician and awareness of contraindications, the article also discusses the impact of IPR on patients. This includes considerations like increased pulp temperature, susceptibility to cavities due to changes in enamel roughness, effects on soft tissues, and post-IPR tooth sensitivity.

Tooth-size discrepancy: a clinical necessity

The subject of this article is the discovery of dento-dental disharmony (DDD) at the end of treatment. Lack of diagnosis is the source of this type of disappointment. The diagnosis of DDD is not easily accessible on clinical examination and the compensations it generates mask it, especially if it is associated with other dysmorphoses. The use of indices, the best-known of which is Bolton's, enables diagnosis with the setup, a pre-treatment model which also has many other prognostic interests. Once DDD has been considered, it can be resolved by adapting dental volumes, either by subtraction or addition. Advances in computerized diagnosis with artificial intelligence are opening up new avenues for the systematic diagnosis of DDD.

Tooth Size Discrepancy in Prospective Orthodontic Patients

Tooth Size Discrepancy in Prospective Orthodontic Patients

Tooth size discrepancy: Digital vs manual measurement

Background/Aim: The aim of this study was to determine the accuracy of overall and anterior Bolton's ratio measurements obtained with an intraoral scanner compared to standard caliper measurements on plaster models. Material and Methods: This study included 33 subjects (18 female and 15 male), aged 12 to 18 years. All subjects were taken impression for the purpose of making study plaster models. In addition, all subjects underwent intraoral scanning for the purpose of creating digital models. Tooth width was measured with a caliper on plaster models, while digital models were analyzed using Cerec Ortho SW 2.0.2 software. The overall and anterior Bolton ratios were derived using both methods. Statistical data processing was performed using an independent t-test. Results: The results obtained using these two methods for measuring the anterior and overall Bolton ratio showed that there was no statistically significant difference in the measurements obtained on plaster models and the measurements obtained by intraoral scanning. For the overall Bolton ratio, T-test was 0.828 and is not statistically significant (p<0.05). The value of T-test for the anterior Bolton ratio was 0.001 and it was also not statistically significant (p<0.05). Conclusions: Determination the overall and anterior Bolton ratio using an intraoral scanner is an accurate and acceptable method for clinical work in orthodontics.

Radiographic evaluation of enamel thickness of permanent teeth: relevance and applicability.

This descriptive observational study aimed to determine clinically relevant and applicable data of enamel thickness (ETH), considering the mesio-distal differences of anterior and posterior permanent teeth and their relationships. The sample consisted of right-sided standardized radiographs of 34 individuals (21 females and 13 males), aged between 13 and 24 (average 16) years, with all permanent teeth intact and without crowding. Four periapical and four interproximal radiographs were obtained and digitized. ETH measurements (mesial to distal contact points at the dentin-enamel junction) were performed after correction for radiographic image magnification. The Students' t-test was applied to the differences between paired means, with the Pearson correlation to evaluate the correlation between them. The mesial and distal ETH increased from the anterior to the posterior teeth. Incisor ETH ranged between 0.60 and 0.84 mm. Canines, premolars, and molars were more than 1.0 mm thick, and molar enamel reached values between 1.26 and 1.44 mm. Distal ETH was significantly greater than the mesial ETH, and progressively thicker from the anterior to posterior teeth. Interproximal reduction (IPR) of the lower central and upper lateral incisors should be avoided, reduced, or performed on their distal surfaces. There is a positive and significant correlation between ETH and the mesial and distal surfaces of the teeth. Periapical radiographs and evaluation of the remaining ETH are necessary in cases of retreatment. The location and number of tooth size discrepancies should be considered in treatment planning and appropriately compensated with IPR.

A Study of Bolton’s Analysis on Permanent Dentition of Nepalese Citizen of Lumbini Province

Introduction: To achieve a good occlusion with satisfactory intercuspation of teeth and a correct overjet and overbite, the maxillary and mandibular teeth must be proportional in size. This cross-sectional study was conducted to assess the Bolton’s tooth size discrepancy in a sample of the Nepalese population of Lumbini Province. Materials and Method: One hundred twenty-fie study casts (50 males and 75 females) were made after making impression of individuals with normal occlusion. Impression was made using alginate impression material, studycasts were made using dental stone type III, and bases were made using dental plaster type II. Individual mesiodistal width of the teeth were measured using a digital vernier caliper to the nearest 0.01mm for the calculation of Bolton’s anterior and overall ratio. The ratios were then compared between male and female. Result: One hundred twenty-five study casts (50 males and 75 females) were made after making impression of individuals with normal occlusion. Impression was made using alginate impression material, study casts were made using dental stone type III, and bases were made using dental plaster type II. A statistically signifiant difference between the summed mesiodistal widths were found between males and females using Independent sample t-test. There was no sexual dimorphism concerning Bolton’s ratio in samples. The overall ratio and anterior ratio were 91.70 ± 1.28 and 77.09 ± 1.57 for males and 91.79 ± 1.34 and 77.29 ± 1.71 for females respectively. The combined overall ratio was 91.75 ± 1.32 and anterior ratio which was 77.21 ± 1.65. Individual mesiodistal width of the teeth were measured using a digital vernier caliper to the nearest 0.01mm for the calculation of Bolton’s anterior and overall ratio. The ratios were then compared between male and female. Conclusion: The sum of mesiodistal dimensions of teeth were greater in males, however, no sexual dimorphism was found in the Bolton ratio. Further, statistically signifiant difference was found in the overall ratio from Nepalese population when compared to the original ratio by Bolton.

Evaluation of the anterior and overall tooth ratios in the Saudi population versus Bolton's standards.

Understanding tooth-size discrepancy is essential in the process of diagnosis of maxillary and mandibular relationship. Due to the high incidence of tooth-size disproportion, Practitioners should consider the high incidence of tooth-size disproportion when planning treatment for their patients, as in many cases, this can be a hindrance to obtaining an ideal result. This study aimed to determine the anterior and overall tooth ratios in the Saudi population and compare them with Bolton's standards. A total of 356 patients were recruited. For the anterior ratio, around 25% of the patients had a ratio equal to Bolton's standards (77.2%). Most subjects (53.7%) had a ratio above 77.2%, and the remaining (20%) had a ratio below 77.2%. The mean amount of anterior mandibular excess was 2.17 ± 2.12 mm, and the mean amount of anterior maxillary excess was 2.16 ± 2.08 mm. For the overall ratio, less than half of the participants (43%) had a ratio equal to Bolton's standards (91.3%). Almost 34% had a ratio above 91.3%, while 23% of the participants had a ratio below 91.3%. The mean amount of overall mandibular excess was 2.54 ± 2.37 mm, and the mean amount of overall maxillary excess was 3.31 ± 3.33 mm. The majority of the study sample had an overall and anterior Bolton ratio that is different from the norms of Bolton's standards, with a tendency for increased overall and anterior ratios. Having specific standards for the Saudi population is important for better clinical assessment and treatment outcomes.

Measuring tooth size discrepancies using Bolton analysis: a comparative cross-sectional study among major ethnicity in Malaysia

BackgroundThe Bolton analysis is one of the commonly used tooth size analysis or diagnostic tools in deriving a treatment plan for orthodontic patients. Many studies have indicated and concluded that normal measurements for one group should not be considered normal for other ethnic groups. The aims and objectives of this study were to investigate the applicability of Bolton’s ratios in the orthodontic population of Malaysian main ethnics, Malay, Chinese, and Indians. Comparisons were made in terms of size and distribution of tooth size discrepancy in the Malaysian orthodontic population and the findings were converted in terms of millimeters.MethodsHundred fifty pre-orthodontic study casts comprised of 52 Malay, 54 Chinese, and 44 Indian patients were selected. Digital calipers (Fowler Pro-Max) linked to Hamilton Tooth Arch Software were used to measure the tooth width and ratios. Statistical analysis was carried out to test for gender differences (independent t-test), to identify the effects of malocclusion and ethnic groups (Two-way ANOVA), and to compare the means of the current study with Bolton’s standards (one sample t-test).ResultsThis study showed that there was no significant difference between the genders of the sample of each ethnicity. There was no correlation found between ethnic groups and malocclusion classes. There was a significant difference when comparing Bolton values with the Malay sample for both ratios. It was found that more Malay subjects presented with maxillary excess contrary to Chinese and Indians who presented more maxillary deficiency for the anterior and overall ratio.ConclusionThere was a significant difference found between the TSD of the three major ethnicities in Malaysia. The Bolton standards can be applied to Malaysian Chinese and Indians but not to Malays orthodontic populations for both anterior and overall ratios. Subsequently, a specific standard should be used for the Malays orthodontic population. It was found that more Malay subjects presented with maxillary excess contrary to Chinese and Indians who presented more maxillary deficiency for the anterior and overall ratio.

Tooth size discrepancies in Kosovar adolescents with different malocclusion classes

The goal of this study was to evaluate tooth size discrepancies in Kosovar adolescents according to the Bolton’s analysis, and to determine the differences between gender and malocclusion classes. A sample of 400 Kosovar adolescents, aged 13–19 years with various malocclusion categories (class I, II, III) according to the Angle’s classification, was randomly selected. The anterior tooth size ratio, overall tooth size ratio, posterior tooth size ratio, as well as distribution of tooth size discrepancies were assessed. The normality of distribution was assessed by the Kolmogorov-Smirnov test, the differences between genders by the Independent Sample T-test, the Mann-Whitney U-test, and differences among malocclusion groups by ANOVA, the Kruskal-Wallis, and the Dunn’s post-hoc tests. The tooth size ratios of men and women did not differ significantly. The results also demonstrated significant differences among the malocclusion classes only for the anterior tooth size ratio (p<0.05). The overall and posterior ratios did not differ significantly within malocclusion classes. The percentages of Kosovar subjects with a deviation of more than 2SD from the Bolton average for the anterior and overall ratios were 41.37 and 23.79, respectively. The genders did not differ significantly regarding tooth size ratios. Among the malocclusion classes, the anterior ratio differed significantly. In Kosovar subjects, tooth size discrepancies tend to be higher compared to Bolton’s averages.

Correction of ectopically placed canine by combining skeletal anchorage and statically determinate force system

The incidence of ectopically erupting canine is quite common, reasons are multifactorial, but usually it's the lack of space which happens due to mesial drift of the posterior teeth or the inherent discrepancy between arch length and tooth size discrepancy. If it's the former, distalization is one of the Go-to treatment modality one can opt for provided the nose and lip relation is optimum and does not warrant for extraction. If it's the latter then extraction remains the only choice. This case report discusses an innovative way of aligning a highly placed canine without taxing the anchorage in all 3 planes with help of Skeletal anchorage and Loop mechanics while also correcting the inclinations and gummy smile without hindering nose-lip relation to a certain extent and also tackling the common problem of anatomically short upper lip.

Geometric analysis of tooth size among different malocclusion groups in a Hispanic population

Tooth size ratio is important for optimal dentofacial esthetics, occlusal interdigitation, and postorthodontic treatment stability. Tooth geometry influences tooth size ratio; therefore, tooth size normative data may not be practical across diverse ethnic groups. This study aimed to determine whether there are significant differences in 3-dimensional tooth size among patients in the Hispanic population with Angle Class I, II, and III malocclusions. The data were collected using intraoral scanned orthodontic study models representing Hispanic orthodontic patients with Angle Class I, II, and III malocclusions. The scanned models were digitized and transferred to a geometric morphometric system. Tooth sizes were determined, quantified, and visualized using contemporary geometric morphometric computational tools. Tooth size was determined for all teeth and showed a significant difference in 4 out of 28 teeth: Maxillary right first molar, mandibular left second molar, mandibular right first molar and mandibular right second molar. This significant difference was noted among females and affected different malocclusion groups. Tooth size discrepancy in the Hispanic population varies among malocclusion groups, and the variation is determined by the participant's gender.

ASSOCIATION BETWEEN BOLTON'S RATIO AND OVER JET DEVIATION IN CLASS II MALOCCLUSION AMONG SOUTH INDIAN POPULATION- A RANDOMIZED CONTROLLED TRIAL

Introduction: The aim of this study is to analyze the difference in the incidence of tooth size discrepancies using boltons ratio in class II malocclusion with varying overjet. The study groups consists of Group I: normal occlus Materials And Methods: ion with ideal overjet and overbite (control), Group II: Class II div.1 with less than 5mm overjet Group III: Class II div.1 with more than 5mm overjet. The anterior and overall tooth size ratio was calculated for each sample as described by Bolton and included in statistical analysis. The mean anterior and Results: overall Bolton ratio of the normal occlusion group (78.8 and 91.88) is slightly greater than the original value. Class II malocclusion with overjet greater than 5mm showing a lowest anterior ratio, the overall ratio for the class II malocclusion group is almost same. Inter proximal Conclusion: slicing may be recommended in the anterior segment to eliminate the interarch discrepancy especially in increased overjet

Using a digital platform to establish odontometric variation based on race, gender and Angle classification.

This study aimed to compare the prevalence of tooth size discrepancies using digital models and a digitally based cast analysis in our cohort based on (i) Angle's Classification; (ii) gender and (iii) race. The mesiodistal widths of teeth in 101 digital models were assessed using computerized odontometric software. A Chi-square test was used to determine the prevalence of tooth size disproportions among the study groups. The differences between all three groups of the cohort were analysed using a three-way analysis of variance (ANOVA). An overall Bolton tooth size discrepancy (TSD) prevalence of 36.6% was observed in our study cohort; 26.7% had an anterior Bolton TSD. No differences existed in the prevalence of tooth size discrepancies between male and female subjects as well as between the different malocclusion groups (P > .05). Caucasian subjects had a statistically significant smaller prevalence of TSD compared to Black and Hispanic patients (P < .05). The prevalence results in this study illuminate how relatively common TSD is and underscores the importance of proper diagnosis. Our findings also suggest that racial background may be an influential factor in the presence of TSD.

Evaluation of Enamel Surfaces after Different Techniques of Interproximal Enamel Reduction

According to the literature, interproximal enamel reduction (IER) has become a consolidated technique used in orthodontic treatments to gain space in particular situations such as dental crowding, non-extractive therapies, tooth-size discrepancies, and prevention of dental relapse. There are different methods to realize stripping, and enamel surfaces resulting after this procedure can be analyzed with SEM. The aim of this study was to analyze how different devices of IER leave the surface of the teeth. One hundred and sixty freshly extracted, intact human lower incisors were included in the study, fixed in a plaster support, and then processed with four different techniques of enamel reduction and finishing. Then, they were divided randomly into eight groups (A1-A2, B1-B2, C1-C2, D, and E), each containing twenty teeth. The A, B, and C groups were divided into two subgroups and then all the teeth were observed at SEM. Each digital image acquired by SEM showed that there were streaks on the surfaces, due to the cutter used. The results of this study showed that only group C2 (tungsten carbide bur followed by twelve steps of medium-fine-ultrafine 3M Soft Lex disks) has a few line, which is very similar to group E (untreated group), while the other groups have a lot of lines and show a rougher final surface.

Single nucleotide polymorphisms in odontogenesis-related genes associated with tooth-size discrepancy

Abstract Introduction: The present study aimed to determine the association between single nucleotide polymorphisms (SNPs) in RUNX2, SMAD6, BMP2, and BMP4 genes in relation to tooth-size discrepancy (TSD). Methods: A cross-sectional study of patients undergoing orthodontic treatment measured the mesiodistal width of permanent teeth from pretreatment dental casts. Sixty-two patients were included in the study and TSD was assessed according to the Bolton analysis. The patients were allocated into a control group (without a TSD), an anterior excess group and an overall excess group. Genomic DNA was extracted from saliva samples, and SNPs previously associated with tooth size were evaluated using a real-time polymerase chain reaction (PCR) system. The Fisher exact test was performed to compare genotype and allele frequencies at an α = 0.05. An Odds Ratio (OR) and 95% Confidence Interval (95% CI) were calculated. Results: The rs59983488 SNP in the RUNX2 gene was significantly related to the presence of anterior mandibular tooth-size excess in allele (T allele: p&lt;0.001; OR = 11.74; 95% CI =2.61–55.80), and genotype models (GT genotype: p = 0.002; OR = 12.69; 95% CI = 2.47–64.83). The rs3934908 SNP in the SMAD6 gene was significantly associated with the presence of an overall maxillary tooth-size excess in allele (T allele: p &lt; 0.001) and genotype models (TT genotype: p = 0.010). Conclusion: The present results suggest that SNPs in RUNX2 (rs59983488) and SMAD6 (rs3934908) genes may be associated with the presence of tooth-size excess.

MULTIDISCIPLINARY APPROACH TO MIDLINE DIASTEMA CAUSED DUE TO HIGH FRENUM ATTACHMENT.

Midline diastema can be defined as a space between the maxillary central incisors. In growing patients midline diastema can be seen as a physiological condition that is self-correct after the eruption of all permanent teeth. This phenomenon of self-correct condition was explained by Broadbent. But not all diastemas are self-correcting. For some patients, the diastema does not close at all. There are various reasons for the occurrence of upper arch midline diastema that must be considered, with the help of intraoral evaluation, including soft tissue/ mucosal diseases, tooth size discrepancies, teeth angulation among others. The case presented described presence of midline diastema due to high frenal attachment in a female aged 17 years. A multidisciplinary approach was taken for this case involving orthodontic and periodontal treatments. Periodontology involvement was for frenectomy.

Anterior Tooth Size Discrepancy in Class III Surgical Patients.

The purpose of the present study was to specify whether there are mesiodistal tooth size discrepancies in the anterior region in patients with dentoskeletal Class III malocclusion who underwent orthognathic surgery and orthodontic treatment and to assess the relationship between anterior Bolton ratio and dentoskeletal cephalometric measurements. The diagnostic dental casts and lateral cephalometric radiographs of 113 nongrowing patients (54 females and 59 males; mean age: 19.96 ± 4.42 years) with dentoskeletal Class III malocclusion who underwent orthognathic surgery and orthodontic treatment were included in the study. The mesiodistal widths of the 6 anterior teeth were measured from dental casts using a digital caliper accurate to 0.01 mm and anterior Bolton ratios were calculated. Lateral cephalograms were digitalized and used to measure 4 skeletal and 4 dental parameters. The mean anterior ratio of Class III surgical patients was 80.1% with a standard deviation of 2.8%. Clinically significant anterior tooth size discrepancies (greater than ±2 standard deviation) were found in 40.7% of the sample, 97.8% of those patients having anterior mandibular tooth excess. No significant correlation was found between the anterior Bolton ratio and cephalometric measurements. Clinicians should consider the probability of tooth size discrepancy in the diagnosis and treatment planning of Class III surgical patients and should perform interventions to eliminate these discrepancies during presurgical orthodontic treatment.