The Hall Technique 10 years on: Questions and answers.

It is ten years since the first paper on the Hall Technique was published in the British Dental Journal and almost 20 years since the technique first came to notice. Dr Norna Hall a (now retired) general dental practitioner from the north of Scotland had, for many years, been managing carious primary molar teeth by cementing preformed metal crowns over them, with no local anaesthesia, tooth preparation or carious tissue removal. This first report, a retrospective analysis of Dr Hall's treatments, caused controversy. How could simply sealing a carious lesion, with all the associated bacteria and decayed tissues, possibly be clinically successful? Since then, growing understanding that caries is essentially a biofilm driven disease rather than an infectious disease, explains why the Hall Technique, and other 'sealing in' carious lesion techniques, are successful. The intervening ten years has seen robust evidence from several randomised control trials that are either completed or underway. These have found the Hall Technique superior to comparator treatments, with success rates (no pain or infection) of 99% (UK study) and 100% (Germany) at one year, 98% and 93% over two years (UK and Germany) and 97% over five years (UK). The Hall Technique is now regarded as one of several biological management options for carious lesions in primary molars. This paper covers commonly asked questions about the Hall Technique and speculates on what lies ahead.

Managing Carious Lesions: Consensus Recommendations on Terminology.

Variation in the terminology used to describe clinical management of carious lesions has contributed to a lack of clarity in the scientific literature and beyond. In this article, the International Caries Consensus Collaboration presents 1) issues around terminology, a scoping review of current words used in the literature for caries removal techniques, and 2) agreed terms and definitions, explaining how these were decided.Dental cariesis the name of the disease, and thecarious lesionis the consequence and manifestation of the disease-the signs or symptoms of the disease. The termdental caries managementshould be limited to situations involving control of the disease through preventive and noninvasive means at a patient level, whereascarious lesion managementcontrols the disease symptoms at the tooth level. While it is not possible to directly relate the visual appearance of carious lesions' clinical manifestations to the histopathology, we have based the terminology around the clinical consequences of disease (soft, leathery, firm, and hard dentine). Approaches to carious tissue removal are defined: 1)selective removal of carious tissue-includingselective removal to soft dentineandselective removal to firm dentine; 2)stepwise removal-including stage 1,selective removal to soft dentine, and stage 2,selective removal to firm dentine6 to 12 mo later; and 3)nonselective removal to hard dentine-formerly known ascomplete caries removal(technique no longer recommended). Adoption of these terms, around managing dental caries and its sequelae, will facilitate improved understanding and communication among researchers and within dental educators and the wider clinical dentistry community.

Managing Carious Lesions: Consensus Recommendations on Carious Tissue Removal.

The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental caries and control activity of existing cavitated lesions to preserve hard tissues and retain teeth long-term. Entering the restorative cycle should be avoided as far as possible. Controlling the disease in cavitated carious lesions should be attempted using methods which are aimed at biofilm removal or control first. Only when cavitated carious lesions either are noncleansable or can no longer be sealed are restorative interventions indicated. When a restoration is indicated, the priorities are as follows: preserving healthy and remineralizable tissue, achieving a restorative seal, maintaining pulpal health, and maximizing restoration success. Carious tissue is removed purely to create conditions for long-lasting restorations. Bacterially contaminated or demineralized tissues close to the pulp do not need to be removed. In deeper lesions in teeth with sensible (vital) pulps, preserving pulpal health should be prioritized, while in shallow or moderately deep lesions, restoration longevity becomes more important. For teeth with shallow or moderately deep cavitated lesions, carious tissue removal is performed according toselective removal to firm dentine.In deep cavitated lesions in primary or permanent teeth,selective removal to soft dentineshould be performed, although in permanent teeth,stepwise removalis an option. The evidence and, therefore, these recommendations support less invasive carious lesion management, delaying entry to, and slowing down, the restorative cycle by preserving tooth tissue and retaining teeth long-term.

Caries management strategies for primary molars: 1-yr randomized control trial results.

Minimal invasive approaches to managing caries, such as partial caries removal techniques, are showing increasing evidence of improved outcomes over the conventional complete caries removal. There is also increasing interest in techniques where no caries is removed. We present the 1-yr results of clinical efficacy for 3 caries management options for occlusoproximal cavitated lesions in primary molars: conventional restorations (CR; complete caries removal and compomer restoration), Hall technique (HT; no caries removal, sealing in with stainless steel crowns), and nonrestorative caries treatment (NRCT; no caries removal, opening up the cavity, teaching brushing and fluoride application). In sum, 169 children (3-8 yr old; mean, 5.56 ± 1.45 yr) were enrolled in this secondary care-based, 3-arm, parallel-group, randomized clinical trial. Treatments were carried out by specialist pediatric dentists or postgraduate trainees. One lesion per child received CR, HT, or NRCT. Outcome measures were clinical failure rates, grouped as minor failure (restoration loss/need for replacement, reversible pulpitis, caries progression, etc.) and major failure (irreversible pulpitis, abscess, etc.). There were 148 children (87.6%) with a minimum follow-up of 11 mo (mean, 12.23 ± 0.98 mo). Twenty teeth were recorded as having at least 1 minor failure: NRCT, n = 8 (5%); CR, n = 11 (7%); HT, n = 1 (1%) (p = .002, 95% CI = 0.001 to 0.003). Only the comparison between NRCT and CR showed no significant difference (p = .79, 95% CI = 0.78 to 0.80). Nine (6%) experienced at least 1 major failure: NRCT, n = 4 (2%); CR, n = 5 (3%); HT, n = 0 (0%) (p = .002, 95% CI = 0.001 to 0.003). Individual comparison of NRCT and CR showed no statistically significant difference in major failures (p = .75, 95% CI = 0.73 to 0.76). Success and failure rates were not significantly affected by pediatric dentists' level of experience (p = .13, 95% CI = 0.12 to 0.14). The HT was significantly more successful clinically than NRCT and CR after 1 yr, while pairwise analyses showed comparable results for treatment success between NRCT and CR (ClinicalTrials.gov NCT01797458).

Saliva fluoride before and during 3 years of supervised use of fluoride toothpaste.

OBJECTIVES: The purpose of the study was to examine pre-brushing saliva fluoride concentrations before and during a large, 3-year, prospective toothpaste study on the effect of post-brushing rinsing on dental caries. The aims were to study saliva fluoride over time and the effect of rinsing on saliva fluoride and to relate saliva fluoride to caries increments and accumulation of plaque. MATERIALS AND METHODS: Saliva samples (baseline and 1, 2, and 3 years) were collected from 11-year-old children attending two schools (A and B) in Kaunas, Lithuania, who refrained from brushing the evening and morning before saliva collection. Numbers of saliva samples collected varied from 264 at baseline to 188 at the 3-year follow-up. Children in school A rinsed with water after daily brushing, while children in school B did not rinse. Total caries and visible plaque were registered at baseline and after 3 years. RESULTS: Mean saliva fluoride concentrations at baseline and after 1, 2, and 3 years from school A (rinsing) were 0.014, 0.026, 0.029, and 0.034 ppm and from school B (no rinsing) were 0.013, 0.028, 0.031, and 0.031 ppm, respectively. Increases in saliva fluoride from baseline were significant (Wilcoxon's test, p < 0.001), but the increase from baseline to year 1 was not statistically significantly different between schools. Saliva fluoride did not increase beyond year 1 and did at no time point differ between schools. Reductions in numbers of tooth surfaces with dental plaque were significantly positively related to the number of caries reversals over the 3 years. CONCLUSIONS: Background saliva fluoride concentration is increased by brushing at least once daily on schooldays, does not increase further over 3 years, and is not affected by rinsing after brushing. CLINICAL RELEVANCE: Continuous use of fluoride toothpaste produces ambient saliva fluoride levels similar to saliva fluoride in areas with fluoridated water.

Dental caries increments and related factors in children with type 1 diabetes mellitus.

The aim of this study was to analyse possible associations between caries increments and selected caries determinants in children with type 1 diabetes mellitus and their age- and sex-matched non-diabetic controls, over 2 years. A total of 63 (10-15 years old) diabetic and non-diabetic pairs were examined for dental caries, oral hygiene and salivary factors. Salivary flow rates, buffer effect, concentrations of mutans streptococci, lactobacilli, yeasts, total IgA and IgG, protein, albumin, amylase and glucose were analysed. Means of 2-year decayed/missing/filled surface (DMFS) increments were similar in diabetics and their controls. Over the study period, both unstimulated and stimulated salivary flow rates remained significantly lower in diabetic children compared to controls. No differences were observed in the counts of lactobacilli, mutans streptococci or yeast growth during follow-up, whereas salivary IgA, protein and glucose concentrations were higher in diabetics than in controls throughout the 2-year period. Multivariable linear regression analysis showed that children with higher 2-year DMFS increments were older at baseline and had higher salivary glucose concentrations than children with lower 2-year DMFS increments. Likewise, higher 2-year DMFS increments in diabetics versus controls were associated with greater increments in salivary glucose concentrations in diabetics. Higher increments in active caries lesions in diabetics versus controls were associated with greater increments of dental plaque and greater increments of salivary albumin. Our results suggest that, in addition to dental plaque as a common caries risk factor, diabetes-induced changes in salivary glucose and albumin concentrations are indicative of caries development among diabetics.

Comparison of diagnostic yields of clinical and radiographic caries examinations in children of different age.

AIM: This was to investigate if the pattern of distribution of caries lesions detected by clinical and radiographic examinations at different diagnostic thresholds changed over a 3-year period during the course of eruption of the permanent dentition. It has been hypothesized that the contribution of bitewing radiography to caries detection in posterior teeth may increase when approximal contacts are established during maturation of the dentition. METHODS: Clinical and radiographic caries recordings were made using the non- cavitated/enamel and cavity/dentine thresholds for caries detection among a group of 12-year-old Lithuanian children with a high caries experience. Examinations were repeated in the same children after 3 years. The bitewing radiographs from both examination sessions were coded to ensure unbiased recordings and were read by a single examiner. RESULTS: The diagnostic yields of the clinical and radiographic examination methods did not change after the permanent teeth had fully erupted. At both examination sessions the clinical examination resulted in the detection of significantly more lesions than did the radiographic method at the non-cavitated level (43- 47% lesions detected by clinical means only and 2-26% by radiographic means only). Only for approximal surfaces at the cavity/dentine diagnostic threshold did radiographs contribute to more lesions (15-16% lesions detected by clinical means only and 38-41% by radiographic means only). Establishment of approximal contacts in the permanent dentition did not increase the relative diagnostic yields of bite-wing radiography in this study group. CONCLUSION: The contribution of the two methods to caries diagnosis depends more on the diagnostic threshold selected than on the stage of maturation of the dentition.

Construct and predictive validity of clinical caries diagnostic criteria assessing lesion activity.

Even though there is no "gold standard" for determining caries lesion activity, it is nonetheless possible to evaluate the validity of such diagnostic measures. The aim of this study was to estimate the construct and predictive validity of caries lesion activity assessments by means of their ability to reflect known effects of fluoride on caries. A three-year trial of the effect of daily supervised brushing with fluoride toothpaste was carried out among 273 12-year-old children. All children were examined clinically according to diagnostic criteria for activity assessment. The relative risk (fluoride vs. control) for caries lesion transitions among diagnostic categories was calculated. Fluoride inhibited progression of caries at all stages of lesion formation while at the same time enhancing lesion regression. The effects were most pronounced for active non-cavitated lesions. It is concluded that the clinical diagnostic criteria have construct and predictive validity for the assessment of caries lesion activity.

Prospective study of the effect of post-brushing rinsing behaviour on dental caries.

Previous studies have indicated that rinsing the mouth with a beaker of water after toothbrushing may compromise the caries reducing effect of fluoride toothpaste. A 3-year clinical trial of daily supervised brushing with fluoride toothpaste at school was used to test the effect of post-brushing rinsing with water on caries increment. A total of 407 children, mean age 11.8 years, attending three schools in Kaunas, Lithuania were enrolled following informed consent of the children and their parents. Caries was recorded at baseline and annually for 3 years. During the study, children in two schools (A and B) performed daily supervised brushing with a 1,500-ppm fluoride toothpaste. Children in school A rinsed their mouths thoroughly with a beaker of water after toothbrushing whereas children in school B were only permitted to spit out once after brushing. Furthermore, the children in these schools were supplied with toothpaste and toothbrushes for use at home and in school. A third school (C), without daily brushing and without supply of toothpaste, served as control. Compliance with the protocol was consistently better in school B. After 3 years 276 children were available for examination. Three-year DMFS increments, including non-cavitated lesions (mean, 95% CI), were: school A, 6.8 (5.3; 8.3); school B, 6.2 (4.6; 7.8), and school C, 12.4 (10.6; 14.1). Mean increments for schools A and B did not differ significantly but were both significantly lower than those of school C (p< 0.001). It is concluded that post-brushing rinsing with water, under the conditions of this study, does not significantly affect the caries reducing effect of a fluoride toothpaste.

Caries preventive effect of sugar-substituted chewing gum.

OBJECTIVES: The aim of this 3-year community intervention trial was to determine the caries preventive effect of sugar-substituted chewing gum among Lithuanian school children, and to assess compliance with the instructions for gum use. METHODS: A total of 602 children, aged 9-14 years, from 28 school classes in five secondary schools in Kaunas, Lithuania, were given a baseline clinical and radiographic caries examination. The schools were randomly allocated to receive one of the following interventions: sorbitol/carbamide gum; sorbitol gum; xylitol gum; control gum; and no gum. Children in the four active intervention groups were asked to chew at least five pieces of gum per day, preferably after meals. The children were reexamined clinically after 1, 2 and 3 years, and radiographically after 3 years. Self-reported compliance was monitored anonymously four times during the study. RESULTS: A total of 432 children were available at the 3-year clinical follow-up examination. The crude mean 3-year caries increments (DMFS--all stages of lesion formation) were 11.8 for the sorbitol/carbamide gum group; 9.0 for the sorbitol gum group; 8.1 for the xylitol gum group; 8.3 for the control gum group; and 12.4 for the no gum group. The adjusted 3-year caries increments were statistically significantly lower in the sorbitol gum group, the xylitol gum group and the control gum group than in the no gum group, whereas no statistically significant difference was seen between the no gum group and the sorbitol/carbamide gum group. Adjusted 3-year caries increments in the xylitol gum group and the sorbitol gum group did not differ statistically significantly from the caries increments in the control gum group. Compliance with the study protocol was better in School C (xylitol gum) than in the other schools. In all schools, compliance decreased over time. CONCLUSION: The results indicate that the caries preventive effect of chewing sugar-free gum is related to the chewing process itself rather than being an effect of gum sweeteners or additives, such as polyols and carbamide.

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.

Reliability of a new caries diagnostic system differentiating between active and inactive caries lesions.

Current scoring systems for dental caries do not consider the dynamic nature of the disease. The aims of the present study were to describe a new set of clinical caries diagnostic criteria which differentiate between active and inactive caries lesions at both the cavitated and non-cavitated levels and to evaluate the reliability of this criteria system in a population with high caries experience. Ten diagnostic codes were defined: 0 = sound; 1 = active (intact); 2 = active (surface discontinuity); 3 = active (cavity); 4 = inactive (intact); 5 = inactive (surface discontinuity); 6 = inactive (cavity); 7 = filling; 8 = filling with active caries; 9 = filling with inactive caries. Distinction between active and inactive caries lesions was made on the basis of a combination of visual and tactile criteria. The inter- and intra-examiner reliability was assessed through repeated examinations of 50 children by 2 recorders over a period of 3 years. The percentage agreement of caries diagnoses varied between 94.2 and 96.2%. The kappa values ranged between 0.74 and 0.85 for intra-examiner examinations and between 0.78 and 0.80 for inter-examiner examinations; 81.6% of all misclassifications involved non-cavitated caries lesions. Disagreement between sound surfaces and non-cavitated active or non-cavitated inactive lesions (31.3 and 31.2%, respectively) was more common than disagreement between non-cavitated active and non-cavitated inactive lesions (10. 6%). The probability of reconfirming a sound, non-cavitated active or non-cavitated inactive caries lesion - given that the surface was diagnosed as either sound, non-cavitated active or non-cavitated inactive at the first examination - was 98.0, 68.7 and 72.5%, respectively. The results show that the use of a new set of clinical caries diagnostic criteria based on activity assessment can be performed with a high reliability, even when non-cavitated diagnoses are included in the criteria system.

Prevalence and severity of dental caries in 12-year-old children in Kaunas, Lithuania 1995.

In order to evaluate suitable strategies for control of dental caries, a longitudinal study of caries progression has been initiated among 12-year-old children in Kaunas, Lithuania. The aim of the present paper was to describe the baseline caries situation in a sample of 12-year-olds, who had been examined using caries diagnostic criteria which differentiate between active and inactive caries lesions at both the cavitated and non-cavitated levels. The mean fluoride concentration in the drinking waters of Kaunas is 0.16 mg/l. A total of 889 children in the 6th grade from seven selected schools were examined. Each tooth surface of all permanent teeth was classified according to one of the following criteria: 0 = sound; 1 = active, surface intact; 2 = active, surface discontinuity; 3 = active, cavity; 4 = inactive, surface intact; 5 = inactive, surface discontinuity; 6 = inactive, cavity; 7 = filled; 8 = filled with inactive lesion; 9 = filled with active lesion; X = extracted. Distinction between active and inactive lesions was made on the basis of a combination of visual and tactile criteria. Virtually all children (99.7%) had experienced at least 1 DMF surface. The mean DMFS was 15.8. Half of the mean caries experience consisted of surfaces with active lesions (7.9), of which two thirds (4.9) were non-cavitated. The mean number of surfaces with non-cavitated inactive lesions was 4.4. The mean DMFT constituted 7.9; 95% of all first molars were affected, followed by the second molars (61%). A comparison of the caries profile according to the present caries diagnostic criteria with those recommended by WHO revealed that the WHO criteria yielded much lower DMFS and DMFT values, because this scoring system does not include non-cavitated caries lesions. The high level of non-cavitated active caries lesions suggests that in this population caries may to a large extent be controlled by simple preventive measures including use of topical fluorides.