Dental general anaesthetic receipt among Australians aged 15+ years, 1998–1999 to 2004–2005

Background Adults receive dental general anaesthetic (DGA) care when standard dental treatment is not possible. Receipt of DGA care is resource-intensive and not without risk. This study explores DGA receipt among 15+-year-old Australians by a range of risk indicators. Methods DGA data were obtained from Australia's Hospital Morbidity Database from 1998–1999 to 2004–2005. Poisson regression modeling was used to examine DGA rates in relation to age, sex, Indigenous status, location and procedure. Results The overall DGA rate was 472.79 per 100,000 (95% CI 471.50–474.09). Treatment of impacted teeth (63.7%) was the most common reason for DGA receipt, followed by dental caries treatment (12.4%), although marked variations were seen by age-group. After adjusting for other covariates, DGA rates among 15–19-year-olds were 13.20 (95% CI 12.65–13.78) times higher than their 85+-year-old counterparts. Females had 1.46 (95% CI 1.45–1.47) times the rate of their male counterparts, while those living in rural/remote areas had 2.70 (95% CI 2.68–2.72) times the rate of metropolitan-dwellers. DGA rates for non-Indigenous persons were 4.88 (95% CI 4.73–5.03) times those of Indigenous persons. The DGA rate for 1+ extractions was 461.9 per 100,000 (95% CI 460.6–463.2), compared with a rate of 23.6 per 100,000 (95% CI 23.3–23.9) for 1+ restorations. Conclusion Nearly two-thirds of DGAs were for treatment of impacted teeth. Persons aged 15–19 years were disproportionately represented among those receiving DGA care, along with females, rural/remote-dwellers and those identifying as non-Indigenous. More research is required to better understand the public health implications of DGA care among 15+-year-olds, and how the demand for receipt of such care might be reduced.Lisa M Jamieson and Kaye F Roberts-Thomso

Prediction of dental arch development: An assessment of Pont's index in three human populations

Pont's Index was established by Pont in 1909 to predict maxillary dental arch width from the sum of the mesiodistal diameters of the four maxillary incisors. The usefulness of Pont's Index is controversial and, as there has been a recent resurgence of interest in its clinical use for establishing dental arch development objectives particularly by nonspecialists, reassessment of the Index in different human populations was considered worthwhile. This study aimed to evaluate Pont's Index in untreated, noncrowded samples of Australian Aborigines (n = 80), Indonesians (N = 60), and white subjects (N = 60). Measurements were obtained directly from plaster casts; they included mesiodistal crown diameters of the four maxillary incisors, as well as intercanine, interpremolar and intermolar maxillary arch widths as specified by Pont. A series of double determinations confirmed the reliability of the method. Considerable individual variability was noted in each population with regard to the difference between observed values and Pont's estimates, ranging from −5.9 mm to +6.2 mm (interpremolar width) and −6.1 mm to +12.7 mm (intermolar width). No person displayed the ideal arch dimensions predicted by the Index, but values were within ± 1.0 mm for 17.5% of the Indonesian sample, 20.6% of the Aboriginal sample, and 30.8% of the white sample. Dental arch width was generally underestimated by the Index in Indonesians who tended to display relatively small tooth size and large arch width. A more even distribution of estimates was noted in Australian Aborigines and white subjects, with the Aborigines showing large tooth size and broad dental arches, and the white subjects displaying smaller tooth size and narrow arches. Correlation coefficients computed between observed and expected values were low in all three populations studied (range r = 0.01 to r = 0.56). Although the concept of a simple index with predictive ability is very appealing to some clinicians, the results of this study have highlighted the marked variation in values of Pont's Index for persons with apparently good occlusions, representing three different human populations. Tooth size variation was poorly correlated with arch width variation, with persons often being over or under Pont's estimation due to variation in tooth dimension, particularly in the size of the maxillary lateral incisor. It is concluded that Pont's Index is unlikely to be a useful clinical predictor of dental arch width and the index should not be used as a guide to dental arch development in contemporary populations.Mulyani Dalidjan, Wayne Sampson, and Grant Townsen

Avaliação da efetividade do método de Tanaka-Johnston para predição do diâmetro mésio-distal de caninos e pré-molares não-irrompidos Evaluation of the effectiveness of the Tanaka-Johnston method for prediction of the mesiodistal diameter of unerupted canines and premolars

No presente estudo, os autores avaliaram o método de predição de Tanaka-Johnston com o objetivo de verificar sua efetividade para os lados direito e esquerdo, para ambos os sexos e para as raças branca, mulato claro, mulato médio, mulato escuro e negra, na cidade de Salvador - Bahia. Com o auxílio de um paquímetro digital, mediu-se o diâmetro mésio-distal dos incisivos inferiores permanentes, caninos e pré-molares, já irrompidos na cavidade bucal, de 98 indivíduos (45 do sexo masculino e 53 do sexo feminino), com idade variando entre 13 e 29 anos. Através de testes estatísticos, compararam-se os resultados obtidos a partir da aplicação das fórmulas de Tanaka-Johnston com os valores reais. Após análise dos resultados, observou-se que a correlação entre os valores estimados pela técnica de Tanaka-Johnston e os valores reais foram maiores para o sexo feminino que para o sexo masculino. Em relação à raça, os coeficientes de correlação foram satisfatórios para todas, sendo maior no arco dentário superior para a raça mulato escuro (0,67) e no arco dentário inferior para a raça mulato claro (0,74). Considerando-se os lados, os achados revelaram um maior coeficiente de correlação para o arco dentário inferior do lado esquerdo (0,61). Pôde-se concluir, neste trabalho, que o método de Tanaka-Johnston, apesar de ter sido preconizado a partir de uma amostra de descendentes europeus, é indicado para predição do diâmetro mésio-distal de caninos e pré-molares não-irrompidos para diferentes raças, sexos e lados dos arcos dentários na amostra estudada.<br>In the present study, the authors evaluated the Tanaka-Johnston method of prediction, with the objective of verifying its effectiveness for the right and left sides, for both genders and for the white, light mulatto, medium mulatto, dark mulatto and black races in the city of Salvador, Bahia. The mesiodistal diameter of the inferior permanent incisors, canines and premolars that had already erupted was measured with the aid of a digital caliper rule in the oral cavity of 98 individuals (45 males and 53 females), aging from 13 to 29 years. The results obtained with the application of the Tanaka-Johnston formulas were compared with the real values through statistical tests. After the analysis of the results, it was observed that the correlation between the estimated values and the real values was greater for females than it was for males. As to race, the coefficients of correlation were satisfactory. They were greater in the superior arch for the dark mulatto race (0.67), and in the inferior arch for the light mulatto race (0.74). Considering the sides, the findings revealed a greater coefficient of correlation for the inferior arch on the left side (0.61). It was concluded that the Tanaka-Johnston method, in spite of originating from a sample of European descendants, is indicated for the prediction of the mesiodistal diameter of canines and premolars in the different races evaluated in this research. The effectiveness of the referred method was also checked for both genders and sides in the studied sample