Tooth Size Analysis Research Articles

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.

Bolton tooth size analysis in a sample of Sudanese adults

Introduction: A correct proportion between the upper and lower teeth is critical to achieving proper occlusal interdigitation, ideal overjet, and good molar intercuspation at the end of orthodontic treatment. Objectives: To determine the anterior and overall Bolton’s ratio in the Sudanese population, investigate gender differences in tooth size ratios, and to compare these results with Bolton’s original ratio norm. Material and Methods: The sample consisted of dental casts of 104 Sudanese University students with normal occlusion (52 females, 52 males), aged between 16-26 years randomly selected from AL- Neelain University. An electronic digital caliper was used to measure the mesiodistal tooth size of the maxillary and mandibular teeth anterior to the second molars. These measurements were then used to obtain Bolton’s ratio. Mean, range, and standard deviation of the anterior and overall ratios were computed for each subject. T-Tests were used to compare gender differences and to investigate differences between the results of this study and Bolton’s original ratio. Results: Anterior and overall Bolton ratios for males were 78.43±2.44 and 93.901±9.8 and for females were 78.29±2.6 and 91.67±3.3 percent, respectively. There were no statistically significant differences between males and females for the anterior and overall ratios P>0.05. The anterior and overall Bolton’s ratios among Sudanese University students were 78.37 ± 2.54, and 92.79± 7.43 percent, respectively. statistically significant difference between this study and Bolton’s study were found in both anterior and overall ratio P<0.05. Conclusion: Bolton’s mean ratios may not be applicable to Sudanese. Keywords Bolton’s ratio; Sudanese population; tooth-size.

The influence of labiolingual and mesiodistal anterior tooth dimensions on interarch relationships: A modified anterior Bolton analysis

Tooth size and morphology of anterior teeth influence interarch relationships. The Bolton analysis uses tooth width to calculate a sum of mandibular to maxillary tooth width ratios necessary for proper occlusion. Several parameters not factored in the Bolton analysis influence occlusion, such as tooth thickness. This study sought to use 3D modeling to develop and assess a tooth size analysis that encompasses labioligual thickness as well as mesiodistal width of anterior teeth. The role of tooth thickness in interarch relationships was studied using simulations in a 3D modeling software (Suresmile). To develop a new chart of interarch ratios based on tooth thickness, a series of simulations were produced with varying tooth thicknesses and widths. The new ratios were evaluated on records from 50 patients. Findings from the simulations suggest that the ideal tooth thickness remains approximately 2mm if the overall tooth width of the dentition increases and the interarch anterior ratio is maintained. The thickness-adjusted anterior mandibular to maxillary tooth ratio ranges from 0.70-0.79 depending on the tooth thickness. This thickness-adjusted ratio provides a superior prediction for the sum of anterior tooth width compared with the Bolton analysis. Tooth thickness affects interarch tooth width ratios and anterior occlusion. A thickness-adjusted ratio can be used to more accurately predict anterior tooth dimensions necessary to achieve proper occlusion.

Management of tooth size discrepancy due to previously extracted maxillary canines

This case report is of a patient whose maxillary canines had been previously extracted. She complained of severe crowding in the lower arch. Intraoral examination revealed that she had Class I molar relationship, nonocclusion in the premolar region, and cross bite. Cast analysis showed tooth size/arch length discrepancy in the lower arch and Bolton's tooth size analysis showed large mandibular excess. Treatment included extraction of mandibular first premolars and fixed mechanotherapy to correct crowding, canine relation, and Bolton's discrepancy. Maxillary premolars were substituted for the extracted canines. At the end of treatment, the patient had a pleasing profile, good intercuspation, ideal overjet, and overbite. Posttreatment cephalometric evaluation showed acceptable maxillary and mandibular incisor inclinations. The occlusion remained stable after orthodontic treatment.

"Evaluation of Tooth Size Discrepancies among Different Malocclusion Groups In Sirte" -Libya

Background: Orthodontic diagnosis and treatment planning requires the patient's history, extra and intra oral examination, analysis of diagnostic records comprising of orthodontic photographs, radiographs and study casts. Tooth-size is the sum of the mesio distal widths of the maxillary and mandibular teeth. For ideal occlusion, teeth in both arches should be proportional in size. Tooth size analysis was presented by Bolton in 1958. The ratio for anterior segment was derived to be 77.2±0.22% and 91.3±0.26% for the whole arch. Material And Methods: Cross sectional data was gathered from the study casts of patients undergoing orthodontic treatment. 115 out of 160 study casts were filtered based upon the inclusion and exclusion criteria. ANB angle and Witt's appraisal were traced on corresponding lateral cephalograms. The mesio distal widths of all maxillary and mandibular teeth from right first molar to left first molar were calibrated with the use of a manual caliper. The readings were then used to compute the anterior and total Bolton ratios. Results: Significantly higher mean anterior tooth ratios were found for Class II (p<0.01) patients. All other ratios were within close range of Bolton's norms. Conclusions: Skeletal Class II patients showed a tendency towards higher mesiodistal widths of teeth in the mandibular anterior region. Keywords: Bolton's norms, Interarch tooth size discrepancy, Skeletal Class I, II and III.

Bolton's ratios and tooth-size discrepancies in a Nigerian population

Objective: The aim of this study was to determine the Bolton's ratios and tooth size discrepancies in a Nigerian population.Method: The Bolton tooth size analysis was performed on 54 dental casts of Nigerian subjects comprising 33 (61%) males and 21 (39%) females (mean 26.6 ± 2.1 years). The overall and anterior tooth size ratios were determined, and gender differences among the sample population was evaluated with t-test. The frequency and magnitude of deviation of theNigerian subjects outside 2 standard deviations from the Bolton's mean was also determined. Result: The result revealed no statistically significant gender differences in interarch tooth size ratios (p> 0.05) and the measurement for both males and females were therefore combined.The overall ratio was 92.1% ± 2.35 and anterior ratio was 78.9% ± 2.64. The overall tooth size discrepancy was present in 9.3% and the 25.9% of the subjects had anterior tooth size discrepancy in relations to more than 2 standard deviations from the Bolton's mean values. Conclusion: The study provided data on tooth size ratios among Nigerian subjects whosevalues were larger than Bolton's data. This study re-emphasized the importance of developing standards for each population.Key words: Tooth size discrepancy, Bolton’s ratios,

Survey on Bolton’s Tooth Size Analysis as Applied to Artificial Teeth

The presence of proportionate teeth size in either arch is a must to obtain an ideal occlusion with good alignment, ideal overjet, ideal overbite and Class I molar relationship. The above facts made us think and to know if this proportion between maxillary and mandibular teeth existed in artificial teeth also? Hence, a survey is undertaken to study the tooth size relation in commercially available artificial teeth. From the results of the present study it was concluded that the anterior and the overall ratios are slightly varied when compared to the standard Bolton's ratios. On comparison the difference between the study ratios and the standard Bolton's ratios were not statistically significant.

Standardizing interarch tooth-size harmony in a Syrian population.

The Bolton analysis is considered to be a good indicator for evaluating the degree of intermaxillary tooth-size harmony, but the possibility of ethnic variation of these values should be examined. Thus, the aim of this study was to calculate both the anterior and overall ratios of mandibular and maxillary tooth sizes for a Syrian sample of harmonious permanent dentitions and to compare these ratios with the data from the Bolton and the Michigan studies. In plaster models of 55 Syrian patients (11-22 years) with neutral occlusion (Angle Class I), harmonious overjet and overbite, no reduction of mesiodistal tooth width or missing teeth, the mesiodistal widths of each tooth from the incisors to the first permanent molars were measured in both arches. In the statistical data analysis, the anterior and overall ratios were calculated according to Bolton. The results for the anterior ratio (78.99 +/- 2.18) and the overall ratio (92.26 +/- 2.06) showed no statistically significant differences by sex (P > .48). These values and the degree of variation were similar to the original data by Bolton. Both studies differed considerably from the values of the anterior ratio found in the Michigan University study, which also shows a higher degree of variability. Nevertheless, the overall ratios of all three studies were very similar. Therefore, the interarch tooth-size analysis and values for a harmonious dentition developed by Bolton can also be transferred to an Arabian or at least a Syrian population.

Bolton tooth-size dsicrepancies among University of Malaya's dental students

The objective of this retrospective study was to investigate what percentage of the dental students in the University of Malaya has a tooth size discrepancy. The sample comprised 40 good quality pre-treatment study models with fully erupted and complete permanent dentitions from first molar to first molar, which were selected from the dental students of the University of Malaya. The mesiodistal diameter tooth sizes were randomly measured manually from first molar to first molar using digital calliper (Mitutoyu) accurate to 0.01 mm, and the Bolton analyses for anterior and overall ratios were calculated by scientific calculator. Reproducibility analysis for intra- and interexaminer calibrations was assessed by measuring 10 study models twice, a week apart. A paired sample t-test and the correlation coefficient were used to evaluate the systematic and random errors of the measurements using Statistical Package for Social Sciences (SPSS) version 12.0. The reproducibility of the intra and inter-examiners for the sum of upper and lower mesiodistal tooth size were high (average mean difference = 0.62, r = 0.82). This study found 47.5% of the samples had anterior, and about 10% had overall· tooth width ratios greater than 2 standard deviations from Bolton's mean. Large percentage of the dental students of the University of Malaya has tooth size discrepancies outside of Bolton 2 standard deviations. It would seem prudentto routinely perform the tooth size analysis and include the findings into orthodontic treatment planning.

A Study about Tooth Size and Arch Width Measurement

Many model analyses methods for measuring tooth size discrepancies, even though they are not always used have been carried out by many authors and formulated for the predetermination of arch size. On the basis of their findings many studies were carried out to find out its reliability, few researchers agreed to the statement made and few pointed out their lack of agreement. Bolton’s method of diagnosing tooth-size discrepancy has been widely used in scientific studies since its publication. Cast analysis is required for all potential orthodontic patients, whether problems are moderate or severe. It is done to evaluate symmetry, alignment (crowding, spacing) and tooth size analysis.

Evaluation of two new methods for measuring tooth widths and performing a Bolton's tooth size analysis

Australian Dental JournalVolume 52, Issue S4 p. S48-S48 Free Access Evaluation of two new methods for measuring tooth widths and performing a Bolton's tooth size analysis D Naidu, D Naidu SupervisorSearch for more papers by this authorD Ong, D Ong SupervisorSearch for more papers by this authorCTC Ho, CTC Ho Supervisor School of Dentistry, The University of Queensland.Search for more papers by this author D Naidu, D Naidu SupervisorSearch for more papers by this authorD Ong, D Ong SupervisorSearch for more papers by this authorCTC Ho, CTC Ho Supervisor School of Dentistry, The University of Queensland.Search for more papers by this author First published: 20 May 2014 https://doi.org/10.1111/j.1834-7819.2007.tb06160.x AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume52, IssueS4December 2007Pages S48-S48 RelatedInformation

Determining Tooth Size Ratio in an Iranian-Azari Population

The aim of this investigation was to determine the tooth size ratio in an Iranian-Azari population. The Bolton tooth size analysis was performed on a sample of 50 plaster models (25 male subjects, 25 female subjects) of Iranian-Azari subjects. The mesiodistal widths of all teeth were obtained and the Bolton anterior ratio and overall ratio were calculated. The mean, range, and standard deviation were calculated for the anterior and overall ratio, and a coefficient of variation was obtained for the tooth size ratio. For the anterior ratio (3-3), the Iranian-Azari had a mean of 78.0 mm with a standard deviation of 3.1; the range was 73.68 to 84.6 mm. For the overall ratio (6-6), the mean was 92.0 mm with a standard deviation of 2.4; the range was 88.09 to 97.5 mm. The results from the Iranian-Azari subjects in the study are similar to Bolton's original data for an American population. These values and the degree of variation were similar to the original data by Bolton, indicating the Bolton analysis for Caucasian samples can be transferred to an Iranian-Azari population. It also confirms no relevant sexual dimorphism exists, and these values are valid for both male and female subjects.

Mesiodistai crown dimension and tooth size ratio of the permanent dentition in CI. I malocclusion sample with spacing in the upper and Iowerjaws

A proper relationship of the total mesiodistal width of the maxillary dentition tothat of the mandibular dentition will favor an optimal post treatment occlusion, thepurpose of this study is to obtain information of the mesiodistal crown dentition and toothsize discrepancy in subject with Cl. I Angle malocclusion with spacing in the upper andlower arches. 30 pairs of dental casts were obtained (15 males, 15 females) weremeasured and analyzed, the results indicates no significant difference between right andleft sides, and non significant regarding tooth size analysis ( Bolton ratio) between malesand females, sexual dimorphism was found regarding mesiodistal crown dimension withgreater mean values for males

Método de medición del índice de Bolton digitalización de la arcada dentaria

The aim of the present study is to introduce a new computerized-aid method to measure mesio-distal tooth size by scanning the dental arches. Once the models are measured, the software calculates the Bolton tooth-size analysis easily, quickly and exactly.The main results indicate that this new system called digital method is found to be as accurate as the traditional caliper method but much more simple and quicker.

Mesiodistal crown dimensions and tooth size discrepancy of the permanent dentition of Dominican Americans.

The purpose of the study was to establish normative data on the mesiodistal crown dimensions of Americans of Dominican background. The Bolton tooth size analysis was performed on a sample of 54 Dominican Americans. The mean, range and standard deviation were calculated for the size of the teeth, and a coefficient of variation was obtained for the tooth size ratio. A 2-sample t-test was used to test for the statistical difference between means. In general, the values obtained for the Dominican American sample closely resembled previous data available for the African American population. The tooth size ratios obtained were compared to the Bolton ratios. The overall ratio was found to be 91.3, equivalent to the Bolton overall ratio, whereas the anterior ratio was 78.1, larger than the 77.1 Bolton ratio. The frequency of tooth size discrepancy outside 2 standard deviations from the Bolton mean was also calculated. An overall tooth size discrepancy was found in 11% of our sample, and 28% of the sample presented an anterior tooth size discrepancy.

Hubungan Rasio Anterior dengan Overjet dan Overbite pada Perawatan Orthodontik

The important role of the tooth size information is in making diagnosis and treatment plan of the cases with malocclusion. A lot of studies have been done in this aspect such as about tooth size with its variation, and also the ratio of maxillary to mandibular tooth size. The most famous tooth size analysis is Bolton analysis with his anterior ratio and overall ratio. Because the accordance of those ratio is not found in all orthodontic cases, some studies (Korbitz, Neff, Moyers and Steadman) tried to relate the anterior ratio with the amount of overjet and overbite in orthodontic treatment. Those relationship was found strong, but there are also other analysis that should be considered in treating orthodontic cases.

Frequency of Bolton tooth-size discrepancies among orthodontic patients

The purpose of this study was to determine the percentage of orthodontic patients who present with an interarch tooth-size discrepancy likely to affect treatment planning or results. The Bolton tooth-size discrepancies of 157 patients accepted for treatment in an orthodontic residency program were evaluated for the frequency and the magnitude of deviation from Bolton's mean. Discrepancies outside of 2 SD were considered as potentially significant with regard to treatment planning and treatment results. Although the mean of the sample was nearly identical to that of Bolton's, the range and standard deviation varied considerably with a large percentage of the orthodontic patients having discrepancies outside of Bolton's 2 SD. With such a high frequency of significant discrepancies it would seem prudent to routinely perform a tooth-size analysis and incorporate the findings into orthodontic treatment planning. (Am J Orthod Dentofac Orthop 1996;110:24-7.)

Reliability of the Bolton tooth-size analysis when applied to crowded dentitions.

The Bolton tooth-size analysis is widely taught and used in orthodontics. However, its reliability has not been documented. The purpose of this study was to evaluate the reliability of the analysis when performed with needle-pointed dividers and a Boley gauge. Four clinicians measured the teeth on 15 sets of casts with two instruments at two sessions. The measurements were used to calculate tooth-size excess. To evaluate the measurement error, the difference between the two analyses made by the same investigator on the same set of casts was calculated. More of the same-investigator analyses were significantly correlated when the Boley gauge was used than when the needle-pointed dividers were used. Between-investigator analyses revealed significant correlations for each measurement session with both instruments. Every investigator was found to have at least one measurement error for each analysis and with each instrument that was as large as a clinically significant result of a Bolton analysis. The results of this study demonstrate that clinically significant measurement errors can occur when the Bolton tooth-size analysis is performed on casts with at least 3 mm of crowding. The Boley gauge demonstrated a higher frequency of significantly correlated repeated measures and thus may be somewhat more reliable for this analysis than the needle-pointed dividers.

Incisor ratio as a tooth size analysis: D. D. Benko, Buffalo New York: State University of New York at Buffalo, 1992

Incisor ratio as a tooth size analysis: D. D. Benko, Buffalo New York: State University of New York at Buffalo, 1992

The occurrence of tooth size discrepancies among different malocclusion groups

This study consisted of 109 patients with varying malocclusions (Class I; Class II, Division 1; Division 2; and Class II surgery) who were treated orthodontically. Tooth size analyses were performed on the pretreatment models of these patients and mesial-distal tooth size ratios were measured as described by Bolton. The incidence of mesial-distal tooth size discrepancies in the malocclusion groups was analyzed and compared with Bolton's means and standard deviations. The results showed no difference in the incidence of tooth size discrepancies from one malocclusion group to another. When the sample was taken as a whole, there was no significant difference in the mean of the mesial-distal tooth size ratios as computed in the present study and compared to Bolton's mean. There were, however, higher standard deviations seen in the present study compared with Bolton's study. Even though there was no significant difference in the incidence of tooth size discrepancies among malocclusion grpups, there was a large number of tooth size discrepancies in each group. Therefore it is suggested that Bolton's tooth size analysis be performed before initiation of orthodontic treatment.