Caries incidence rates in Swedish adolescents and young adults with particular reference to adjacent approximal tooth surfaces: a methodological study

OBJECTIVES: The objective was to assess the dependence of the caries status of the adjacent approximal surface on the incidence of approximal caries. METHODS: At baseline, the material consisted of a cohort of 536 Swedish children. The individuals were followed through annual bitewing radiographs from the age of 11-13 to 21-22 years. A radiographic scoring system was used to assess the caries status of the surfaces: scores 0 and 1 = sound surface to score 4 = caries in the outer half of the dentine. A model was used to calculate the dependence of the caries status of adjacent approximal tooth surfaces. The unit of analysis was a pair of adjacent approximal surfaces and in all, 12 pairs of posterior approximal surfaces were analysed. RESULTS: The individual caries rates of the 24 posterior approximal surfaces ranged from 1.3 to 8.3 new caries lesions per 100 tooth surface-years. The caries rate of an approximal tooth surface depended on the caries status of the adjacent surface: a sound surface next to a sound surface had a relatively small risk of developing caries, while the risk increased 1.6-32.3 times if the adjacent surface was in a caries state as judged radiographically. The distal surface of the first molar developed caries more often than the mesial surface of the second molar. CONCLUSIONS: The caries rate of an approximal tooth surface was 1.6-32.3 times higher if the adjacent surface was in a caries state compared to when the latter was sound.     

Changes in prevalence of approximal caries in 17-year-olds and related restorative treatment strategies over a 6-year period

Two cohorts of 17-yr-olds treated in a municipal child dental service in 1978-79 and 1984-85 had bitewing radiographs taken at the examination before the last course of treatment in the service. All radiographs were read by one examiner, who did not know to which cohort the individual belonged. The subsequent treatment was recorded from the treatment records by another examiner, who was unaware of the results of the radiographic examination. According to radiographic scores, the proportion of decayed or filled (DFS) approximal surfaces had decreased from 23.2% to 17.4% during the period (difference: 25%). The proportion of unfilled surfaces which were decayed (DS) had remained almost constant, while 9.6% of the surfaces were filled (FS) in 1978-79 compared to 3.1% in 1984-85 (difference: 68%). Thus, in spite of a 25% decrease in total caries experience (DFS), a reduction of 68% would be claimed if fillings (FS) were interpreted as expression of disease prevalence. The risk of an approximal surface being filled decreased to about one fifth from 1978-79 to 1984-85, and the risk of being filled was nearly three times as high for approximal surfaces of children who already had approximal fillings at the time of examination. Thus, both the year of examination and the subject's previously received treatment seemed to influence the treatment strategy of the dentist.     

Caries behaviour in Danish teenagers: a longitudinal radiographic study

Summary. Coinciding with the decline in caries prevalence observed among children and adolescents, changes in the distribution and progression rates of the disease have been found. The aim of this study was to assess occlusal and approximal caries behaviour and disease distribution within a group of Danish teenagers, and to determine whether the presence of occlusal fillings at baseline could be used as predictor for caries behaviour. The material used was bitewing radiographs taken twice in 197 adolescents, at the age of 14·5 years (first examination) and approximately 3 years later (second examination). Of the occlusal surfaces assessed at both examinations, 93% remained unchanged, 1% developed new carious lesions, and 6% had been filled during the study period. All occlusal dentinal lesions found at the first examination and left unrestored during the study period did not appear to have progressed. Of the approximal surfaces, 86% remained unchanged, 9% developed caries, 2% showed caries progression, and 2·5% had been filled during the study period. 22% of the approximal enamel lesions found at the first examination progressed into the dentine during the study period. 18% of all the children were responsible for 50% of the total number of new lesions and fillings. The proportion of children exhibiting new lesions at the second examination was almost evenly distributed among children with and without occlusal fillings at the first examination. In the group of children with occlusal fillings at baseline, significantly more individuals than in the other group showed new fillings and lesions with and without progression. It is concluded that the progression percentage for approximal enamel lesions to penetrate into the dentine was low, that the distribution of new carious lesions and fillings among the children was polarized, and that the presence of occlusal fillings at baseline could not be used to identify children with a specific caries behaviour.     

Progression of approximal caries in relation to iatrogenic preparation damage.

The aim of the present study was to evaluate the effect of iatrogenic preparation damage on the need for operative caries treatment of approximal surfaces, adjacent to Class II amalgam restorations. The material was collected by 77 dentists from the Public Dental Child Health Service in Denmark. It consisted of die-stone models of 187 first-time Class II preparations, adjacent to 190 unfilled approximal surfaces of 58 primary and 132 permanent teeth. The cavity preparations were performed in children between 4 and 17 years of age. They were all filled with amalgam. Information about operative treatment and exfoliation or extraction of the preparation teeth and the adjacent teeth during the following seven years was obtained from the patients' records. Stereomicroscopic examination of the models revealed preparation damage on 64% of the unfilled approximal surfaces in primary teeth and on 69% of the corresponding test surfaces in permanent teeth. During the observation period, operative treatment was performed on 10% of the undamaged test surfaces in primary teeth and on 35% of the damaged ones (p less than 0.05). The corresponding figures for test surfaces in permanent teeth were 6% and 15% (p less than 0.05). It is concluded that iatrogenic preparation damage is a frequent side-effect of operative intervention with approximal caries lesions, and represents a dental health problem, since the damage increases caries progression and the perceived need for restorative therapy of the adjacent teeth.     

A comparison of clinical and radiographic caries diagnoses in posterior teeth of 12-year-old Lithuanian children.

Bite-wing radiography has been recommended for use in adolescents as clinical examinations alone may lead to underestimation of carious lesions in approximal and occlusal surfaces. The aim of this study was to describe the relationship between clinical and radiographic caries diagnoses among 12-year-old Lithuanians using a new clinical scoring system which differentiates between cavitated and non-cavitated caries lesions. Eight hundred and seventy-two children were examined clinically and two standardized posterior bite-wing radiographs were taken of each participant. Bite-wing radiography contributed significantly to the total number of lesions diagnosed only at the dentin level in approximal surfaces. Clinical examination performed better than radiographic examination at the non-cavitated/enamel level, particularly on occlusal surfaces. Less than 2% of the clinically sound surfaces were diagnosed with dentin lesions/fillings radiographically. When using the cavitated level of clinical diagnosis, the frequency of 'hidden' caries lesions increased from 1.9 to 2.9% in approximal surfaces, and from 1.7 to 5. 2% in occlusal surfaces. The intra-examiner reliability data for the clinical and radiographic recordings supported the conclusion of an additional diagnostic value of bite-wings only for approximal surfaces. The findings demonstrate that the diagnostic yield of bite-wing radiography is higher for approximal than for occlusal surfaces. The efficacy of bite-wings depends on the refinement of the clinical caries diagnostic criteria. 'Hidden' caries does not seem to be a major problem when the clinical caries diagnostic criteria include non-cavitated diagnoses.     

Incidence and prediction of filled teeth from 12 to 18 years of age in a district in Norway

Abstract – The present study investigated whether the incidence or prevalence of filled teeth/ approximal surfaces at one age could be predictive for the incidence in another period or for the prevalence at the age of 18. The study was conducted in 12–18-yr-olds in Norway. Regression analysis showed that the best prognosis for subsequent incidence of filled teeth/approximal surfaces could be made at the age of 15. By using regression analysis or discriminant analysis it was possible at the age of 15 to predict with high accuracy those who would acquire more fillings than the median at the age of 18. Discriminant analysis with one predictor variable is suggested for clinical use. The variable that discriminated best between above and below median number of new fillings in the period 15 18 yr was untreated lesions in the inner half of the enamel in the approximal surfaces of premolars and molars at the age of 15. From the use of simple prediction tools, it was concluded that individuals at the age of 15 with a low prevalence of filled teeth/filled approximal surfaces and without untreated approximal lesions would be subjected to a low incidence of new fillings until the age of 18.     

Incidence and prediction of filled teeth from 12 to 18 years of age in a district in Norway

The present study investigated whether the incidence or prevalence of filled teeth/approximal surfaces at one age could be predictive for the incidence in another period or for the prevalence at the age of 18. The study was conducted in 12-18-yr-olds in Norway. Regression analysis showed that the best prognosis for subsequent incidence of filled teeth/approximal surfaces could be made at the age of 15. By using regression analysis or discriminant analysis it was possible at the age of 15 to predict with high accuracy those who would acquire more fillings than the median at the age of 18. Discriminant analysis with one predictor variable is suggested for clinical use. The variable that discriminated best between above and below median number of new fillings in the period 15-18 yr was untreated lesions in the inner half of the enamel in the approximal surfaces of premolars and molars at the age of 15. From the use of simple prediction tools, it was concluded that individuals at the age of 15 with a low prevalence of filled teeth/filled approximal surfaces and without untreated approximal lesions would be subjected to a low incidence of new fillings until the age of 18.     

Prevalence of approximal caries in posterior teeth in 15-year-old Swedish teenagers in relation to their caries experience at 3 years of age

The aim of the present investigation was to study the prevalence of approximal caries lesions and fillings in posterior teeth at 15 years of age in a prospectively followed Swedish population (n = 568), with special reference to their caries experience at the age of 3 years. Only approximal surfaces were recorded, since all children in the Community of J?nk?ping have had fissure sealing performed on all caries-free permanent molars. At 15 years of age, the mean number of approximal tooth surfaces with initial caries lesions (D(i)a), manifest caries lesions and fillings (D(m)Fa) and total caries experience and fillings (D(i + m)Fa)--recorded on bitewing radiographs--was 2.78 , 0.45 and 3.23, respectively. One third of the adolescents had no approximal caries or fillings; the D(i)a constituted 86% of the D(i + m)Fa. Children with manifest caries at 3 years of age had a higher risk of developing approximal caries in their permanent teeth than caries-free children at the same age (41 vs. 17%). Furthermore, children who were caries-free at 3 years of age were more likely to remain caries-free at 15 years of age compared to children with manifest caries (37 vs. 17%). All these differences were statistically significant (p < 0.001). Additionally, early childhood caries experience (developed before 3 years of age) had a greater predictive value than late childhood caries experience (developed between 3 and 6 years of age) concerning approximal caries at 15 years of age.     

Active and inactive root surface caries lesions in a selected group of 60- to 80-year-old Danes.

In 90, 60- to 80-year-old patients with teeth retained in both jaws (mean 20.4 +/- 4.3), a total of 1,092 root surface lesions were recorded. Of these 156 were diagnosed as active caries lesions, whereas 509 were considered inactive, and 427 were filled. About 60% of the elderly had one or more active lesions and 79% had fillings. Seventy percent had more than 8 filled or carious (active or inactive) surfaces. The percentage of carious and filled root surfaces in relation to surfaces at risk demonstrated that the buccal surfaces of lower molars and premolars and upper canines were the most severely affected (RCI = 70%) with fillings predominating on easily accessible surfaces. A constant relationship between active and inactive lesions was found on all other surfaces but third molars and upper incisors. The data suggest that active and inactive root caries lesions must be diagnosed as separate entities if the dynamic nature of root surface caries is to be explored in epidemiological studies and clinical trials.     

Behaviour of approximal carious lesions assessed by clinical examination after tooth separation and radiography: a 2.5-year longitudinal study in young adults.

This study aimed to record and monitor over a 2.5-year period the occurrence of cavitation and lesion depth progression in approximal surfaces with radiographic caries at baseline. In total, 66 approximal sites (in 29 students), where at least one of the contacting surfaces had radiographic caries, were selected to take part in the study. A clinical examination undertaken before and after tooth separation in order to assess the presence/absence of cavitation was repeated every sixth month. To monitor lesion progression bite-wing radiographs were taken every sixth month, too. After each series of examinations, surfaces judged to be prone for disease progression were referred to operative caries treatment. In surfaces with radiographic dentinal caries at baseline the cavitation prevalence following tooth separation found at the various recall examinations ranged from 20 to 44%. In surfaces with radiographic enamel caries at baseline this prevalence ranged from 4 to 8% at the various recall examinations. In dentinal lesions found with an intact surface at baseline, the risk of cavitation development during the first 1.5-year period was assessed to be up to 22%. After this period no new cavitations were found in previously intact dentinal lesions. In intact enamel lesions the risk of cavitation formation was found to be 3% during the first 1-year period. After this period no new cavitations developed in previously intact enamel lesions. Three of 7 lesions, which showed radiographic caries progression from the outer one third to the inner two thirds of the dentine during the observation period, had intact surfaces at baseline. On the basis of these results it is recommended to re-examine carefully intact, dentinal lesions by repeated clinical examination after tooth separation and by radiography about 1-1.5 years after baseline.     

Correlation of cariogenic bacteria and dental caries in adults

Many studies suggest that mutans streptococci (MS), Lactobacillus (LB), and salivary buffering capacity are important risk factors for dental caries. However, target populations for most studies were children. In adult patients, the same risk factors affect the number of fillings or prostheses or secondary caries. It is therefore important to investigate these risk factors as predictors of caries in adults. In the present study, we evaluated the oral conditions of adult subjects at private dental offices using bite-wing radiographs. Detection of salivary LB level using Dentocult LB had a statistically significant correlation with the number of flat surface caries and approximal caries (P < 0.001). Detection of salivary MS level using Dentocult MS and salivary buffering capacity did not predict dental caries. Thus, detection of salivary LB level using Dentocult LB may be a useful tool for detecting approximal and secondary caries.     

Caries incidence and lesion progression from adolescence to young adulthood: a prospective 15-year cohort study in Sweden

The objectives were (1) to assess caries development, including the incidence and rate of lesion progression, in a Swedish cohort from adolescence to young adulthood and (2) to compare the caries incidence rates in adolescents with those of young adults. The original material consisted of 536 children aged 11-13 years at baseline. This cohort had been followed through annual bitewing radiographs to 21-22 years of age. In 1998-1999, 250 of these individuals were re-examined at the age of 26-27, and the new caries data were added to the original data. The results showed that fewer new enamel lesions developed on approximal surfaces during young adulthood than during adolescence; the caries incidence rates for enamel lesions decreased from 4.3 in the age group 12-15 years to 2.7 new caries lesions/100 surface-years in the age group 20-27 years. The same applied to the rate of lesion progression, where the corresponding values from the enamel-dentin border to the outer dentin were 32.5 for the youngest and 10.9 new lesions/100 surface-years for the oldest age group. The caries incidence of outer dentin lesions on approximal surfaces was low but increased from 0.2 in the age group 12-15 years to 0.9 new outer dentin lesions/100 surface-years in the age group 20-27 years. The incidence rates varied considerably between different tooth surfaces. Also for occlusal surfaces, fewer new dentin lesions developed during young adulthood than during adolescence; the incidence was 2.0 new dentin lesions/100 surface-years in the youngest age group and 0.7 during young adulthood. At the age of 13, the proportion of DFS of occlusal surfaces predominated over DFS of approximal surfaces but at the age of 26-27 the proportions of occlusal and approximal DFS were almost equal.     

Comparison of radiographic and clinical diagnosis of approximal and occlusal dental caries in a young adult population

OBJECTIVES: The aims of the study were: (1) to determine if bitewing radiographs provided additional diagnostic yield for occlusal and approximal dental caries in adults aged between 17 and 30 years of age when compared with a clinical examination only, (2) how this translated into the measurement of dental caries experience, and (3) to determine the influence of water fluoridation on the diagnosis of dental caries in occlusal and approximal surfaces by clinical examination alone and by radiographic examination. METHODS: Between November 2002 and March 2003 a total of 879 subjects aged 17-30 years had a clinical examination using visual and tactile criteria. Subsequent to this examination, bitewing radiographs were taken and viewed separately and blind. Approximal and occlusal surfaces of molars and premolars were examined on the radiographs. RESULTS: Between 22.9-32.9% of approximal caries and 75.9-82.9% of occlusal caries was detected by clinical examination, while 93.1-97.1% of approximal caries and 33.1-42.6% of occlusal caries was detected by radiographic examination. In addition, while only 0.97% of clinically sound approximal surfaces and 0.83% of clinically sound occlusal surfaces were diagnosed with dentine caries on the radiographs, 67.1-77.1% of approximal caries was detected by radiographs alone, an additional diagnostic yield of 204-336%. The DS score increased 45-46% and the DMFS score increased 6-11% from the clinical examination with the addition of the radiographic information (P<0.001). CONCLUSIONS: The prevalence of approximal and occlusal caries was underestimated when clinical means only were employed. There was a significant increase in DS and DMFS scores from the clinical examination only when radiographic information was added across all age groups (P<0.001). This study confirms the value of bitewing radiographs in caries diagnosis.     

A comparison of radiographic occlusal and approximal caries diagnoses made by 240 dentists.

Radiographs of occlusal (n = 20) and approximal (n = 24) surfaces of extracted teeth were examined by 240 dentists before participating in continuing education courses dealing with caries diagnosis and treatment decisions. The radiographic caries diagnoses were treated in accordance with the receiver operating characteristic (ROC) technique, in which the area beneath the ROC curve (A, value) indicates the quality of the observations. The frequencies of false positives made in dentin radiographically were higher for approximal (20.7%) than for occlusal caries (12.3%). The quality of pooled radiographic diagnoses of occlusal dentin lesions for all observers was significantly better than diagnoses of approximal caries in dentin. A statistically significant relationship between the observer's qualities of diagnosis of caries on approximal and occlusal surfaces (P = 0.045) was found. For diagnosis of dentin caries on approximal surfaces the mean Cohen kappa was 0.74 (standard deviation (s), 0.12; range, 0.39-0.95), and the corresponding values for occlusal surfaces were 0.70 (s, 0.14; range, 0.25-0.98). In the material under study the dentists were at least as good at diagnosing dentin caries occlusally as approximally. To avoid overtreatment, the observer's diagnostic threshold should ideally be adjusted towards strict criteria when a positive diagnosis is synonymous with a filling. The diagnostic thresholds were stricter in diagnosing occlusal surfaces than for approximal surfaces, indicating a more optimal strategy among dentists while diagnosing occlusal dentin lesions in a population with low caries prevalence.     

Different analytical approaches in an experimental cohort study on preventive measures for caries in adolescents. A comparison between incidence density and increment analysis

AIM: To use different analytical approaches to data from a longitudinal, quasi-experimental study evaluating caries-preventive measures in order to estimate the differences in results due to the analytical tool used. METHODS: 1,165 patients at high risk for caries underwent yearly examinations in 1996, 1997 and 1998 and randomly received one out of four tested preventive measures. Two analytical methods were used: (1) increment was calculated using the indices DMFS(a) and D(e)MFS(a), (2) incidence density was calculated for each individual using new approximal dentin lesions or dentin and enamel lesions in the numerator and the risk time for the surfaces in the denumerator. The Poisson regression with overdispersion was used for multivariate modelling of the outcomes. RESULTS: In all analyses of approximal dentine as well as dentine and enamel caries bad oral health at baseline increased the risk of new approximal dentine caries. In the incidence analysis poor oral health behaviour also increased the risk. CONCLUSION: Since the difference between the two analytical methods are small for young individuals the method of preference would be increment analysis.     

Migration background: a risk factor for caries development during adolescence

The influence of child and parental migration background on the risk of approximal caries increment in Swedish adolescents was investigated. This retrospective longitudinal register-based cohort study included all 13-yr-old adolescents (n = 18,142) who were resident in the County of Stockholm, Sweden, in 2000, and followed them up to 19 yr of age. At follow-up, 15,538 subjects were examined. Caries data [decayed, missing, and filled teeth/surfaces (DMFT/S)], were collected from a dental database. Socio-demographic determinants were collected from Swedish National Registers. After adjustments for socio-demographic confounders, logistic regression analysis revealed that adolescents with foreign-born parents, irrespective of whether the child was born in Sweden or abroad, exhibited a significantly elevated risk for approximal caries increment (DMFSa > 0), and developed, on average, 0.53 and 1.14 more approximal caries lesions, respectively, compared with their counterparts with Swedish-born parents. Furthermore, adolescents born in eastern Europe exhibited an increased risk for approximal caries increment (DMFSa > 0) and developed, on average, 1.06 more approximal caries lesions compared with Swedish-born adolescents. In conclusion, parental migration background must be considered as a risk factor for caries development during adolescence, irrespective of whether or not the adolescent was born in Sweden.     

Relationships between occlusal or free-smooth and approximal caries in mixed dentition

This cross-sectional study aimed to examine the relationships between free-smooth or occlusal surfaces and approximal caries in 104 schoolchildren between 6 and 8 years of age. Caries diagnosis was clinically and radiographically assessed, and white spot lesions, evident caries lesions or restorations, as well as radiolucence in enamel were considered to be caries. In the studied subjects, the correlations were analyzed in the 1st primary molars (Ds), the 2nd primary molars (Es), the 1st permanent molars (6s), and all molars. The data were statistically analyzed by chi-square test. Significant correlations between occlusal surface caries and approximal surface lesions were observed in Ds and Es teeth and in all molars, but not for 1st permanent molars. For free-smooth surface, these correlations were significant only for Es and all molars. Sensitivity and specificity for occlusal surface as an indicator of approximal caries in the same tooth type ranged from 73% to 83% and 51% to 58%, respectively. Similarly, for free-smooth surface the values varied from 22% to 60% and 57% to 90%, respectively. Sensitivity and specificity for occlusal surface caries in identifying subjects with approximal caries were 78% and 70%, respectively; for free-smooth surface, the corresponding values were 59% and 65%, respectively. The results suggest that visually detected caries lesions are indicative of approximal caries. Thus, if a certain risk limit is defined and the corresponding number of caries lesions in different surfaces is reached, the risk is above the threshold and could be a practical guideline on the need for radiography in this age group of patients with "moderate caries experience".     

Caries rates related to approximal caries at ages 11-13: a 10-year follow-up study in Sweden

Predicting future caries risk is a difficult but important clinical task. The aim of this study was to analyze radiographically the relationship between approximal caries (4d-7m) at ages 11-13 (baseline) and future approximal caries. We followed 534 individuals prospectively through annual bitewing radiographs from 11 to 22 years of age. Two measures were used: individual-based incidence of the first new approximal caries lesion and surface-based incidence of approximal lesions. In the group with no approximal caries lesions at baseline, the individual-based incidence was 19 first new approximal lesions/100 person-years; the corresponding value for those with 3 approximal lesions at baseline was 71. Individuals with no approximal lesions at baseline developed 3.1 new lesions/100 tooth surface-years; the corresponding value for those with 3 lesions at baseline was 7.7. The highest risk for developing new approximal lesions was within the first 2 years after baseline.     

Radiographic display of carious lesions and cavitation in approximal surfaces: Advantages and drawbacks of conventional and advanced modalities

Background. Treatment strategies have changed with efforts on arresting carious lesions suspected to have an intact surface sparing operative treatment for cavitated lesions. Radiography is still the most recommended adjunct method in the diagnosis of clinically inaccessible approximal surfaces. Bitewing radiography. The major drawback of bitewing radiography for caries diagnosis is that the clinical state of the surface cannot be determined; i.e. if cavitation has developed or the demineralized surface is still intact. Based on studies of the relationship between radiographic lesion depth and clinical cavitation in approximal surfaces, a threshold for operative treatment decision has been suggested when a lesion is observed radiographically more than one-third into dentine. However, the results from previous studies are contradictory and the majority of studies are ～25 years old. In addition, there are few longitudinal observational studies on the behaviour of dentinal carious lesions, particularly in adults. Cone beam computed tomography. Cone beam CT is an advanced 3-dimensional radiographic modality, which seems much more accurate than intra-oral modalities for displaying cavitation in approximal surfaces. Nonetheless, there are several drawbacks with CBCT, such as radiation dose, costs and imaging artefacts. Therefore, CBCT cannot be advocated at current as a primary radiographic examination with the aim of diagnosing cavitated carious lesions. Conclusions. Bitewing radiography is, thus, still state-of-the-art as an adjunct in diagnosing carious lesions in clinically inaccessible approximal surfaces. The risk for cavitation is related to lesion depth, but new studies are needed in both child and adult populations to validate current thresholds for the operative treatment decision based on the radiographic lesion depth.