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Featured researches published by Jana Olak.


Caries Research | 2005

Similarity of the Effects ofErythritol and Xylitol on SomeRisk Factors of Dental Caries

Kauko K. Mäkinen; Mare Saag; Kauko Isotupa; Jana Olak; Rita Nõmmela; Eva Söderling; Pirkko-Liisa Mäkinen

Several sugar alcohols (polyols) have been promoted as potential sugar substitutes in caries limitation. However, differences in the effects of simple alditol-type sugar alcohol homologues on dental plaque have not been compared in clinical tests. The effects of 6-month use of erythritol (a sugar alcohol of the tetritol type), xylitol (a pentitol) and D-glucitol (sorbitol, a hexitol) were investigated in a cohort of 136 teenage subjects assigned to the respective polyol groups or to an untreated control group (n = 30–36 per group). The daily use of the polyols was 7.0 g in the form of chewable tablets, supplemented by twice-a-day use of a dentifrice containing those polyols. The use of erythritol and xylitol was associated with a statistically significant reduction (p < 0.001 in most cases) in the plaque and saliva levels of mutans streptococci. The amount of dental plaque was also significantly reduced in subjects receiving erythritol and xylitol. Such effects were not observed in other experimental groups. Chemical analyses showed D-glucitol to be a normal finding in dental plaque while xylitol was less consistently detected. Erythritol was detected in measurable amounts only in the plaque of subjects receiving this polyol. Erythritol and xylitol may exert similar effects on some risk factors of dental caries, although the biochemical mechanism of the effects may differ. These in vivo studies were supported by cultivation experiments in which xylitol, and especially erythritol, inhibited the growth of several strains of mutans streptococci.


Caries Research | 2014

Effect of Erythritol and Xylitol on Dental Caries Prevention in Children

Sisko Honkala; Riina Runnel; Mare Saag; Jana Olak; Rita Nõmmela; Silvia Russak; Pirkko-Liisa Mäkinen; Tero Vahlberg; Gwen Falony; Kauko K. Mäkinen; Eino Honkala

Objective: The aim of this study was to test the efficacy of long-term, daily intake of erythritol and xylitol candy, compared with sorbitol candy, on the development of enamel and dentin caries lesions. Methods: The study was a double-blind randomized controlled prospective clinical trial. Altogether 485 primary school children, first- and second-graders at baseline, from southeastern Estonia participated in this 3-year intervention. Each child consumed four erythritol, xylitol or sorbitol (control) candies three times per school day. The daily intake of polyol was about 7.5 g. The International Caries Detection and Assessment System (ICDAS) was used in the clinical examinations by four calibrated examiners at baseline and at 12, 24 and 36 months. Results: The annual examination analyses and the follow-up analyses confirmed that the number of dentin caries teeth and surfaces at 24 months follow-up and surfaces at 36 months follow-up was significantly lower in the mixed dentition in the erythritol group than in the xylitol or control group. Time of enamel/dentin caries lesions to develop and of dentin caries lesions to progress was significantly longer in the erythritol group compared to the sorbitol and xylitol groups. Also the increase in caries score was lower in the erythritol group than in the other groups. Conclusions: In the follow-up examinations, a lower number of dentin caries teeth and surfaces was found in the erythritol group than in the xylitol or control groups. Time to the development of caries lesions was longest in the erythritol group. Trial registration: ClinicalTrials.gov Identifier NCT01062633.


International Journal of Dentistry | 2011

Measuring Dental Caries in the Mixed Dentition by ICDAS

Eino Honkala; Riina Runnel; Sisko Honkala; Jana Olak; Tero Vahlberg; Mare Saag; Kauko K. Mäkinen

Caries has traditionally been assessed with WHO criteria including only obvious caries lesions. ICDAS has been developed to detect also the enamel caries lesions. This study aims to study caries and the associations of the number of caries lesions between the permanent and primary molars with ICDAS in the mixed dentition of the first and second grade primary school children. The clinical examinations of 485 children were conducted by four examiners with high reproducibility (inter- and intraexaminer kappas >0.9). The mean number of caries lesions—especially dentine caries—seemed to be higher in the second primary molars than in the first permanent molars. There were significant correlations between the number of lesions on occlusal and lingual surfaces between the primary and permanent molars. Enamel caries lesions, restorations, and caries experience did not increase according to age. Therefore, caries might be increasing in this population. As a conclusion, ICDAS recording seems to give appropriate information from the occurrence of caries lesions and its correlations between the primary and permanent teeth and surfaces.


Journal of Dentistry | 2013

Effect of three-year consumption of erythritol, xylitol and sorbitol candies on various plaque and salivary caries-related variables

Riina Runnel; Kauko K. Mäkinen; Sisko Honkala; Jana Olak; Pirkko-Liisa Mäkinen; Rita Nõmmela; Tero Vahlberg; Eino Honkala; Mare Saag

OBJECTIVE The objective of the present paper is to report results from oral biologic studies carried out in connection with a caries study. METHODS Samples of whole-mouth saliva and dental plaque were collected from initially 7- to 8-year-old subjects who participated in a 3-year school-based programme investigating the effect of the consumption of polyol-containing candies on caries rates. The subjects were randomized in three cohorts, consumed erythritol, xylitol, or sorbitol candies. The daily polyol consumption from the candies was approximately 7.5 g. RESULTS A significant reduction in dental plaque weight from baseline (p<0.05) occurred in the erythritol group during almost all intervention years while no changes were found in xylitol and sorbitol groups. Usage of polyol candies had no significant or consistent effect on the levels of plaque protein, glucose, glycerol, or calcium, determined yearly in connection with caries examinations. After three years, the plaque of erythritol-receiving subjects contained significantly (p<0.05) lower levels of acetic acid and propionic acid than that of subjects receiving xylitol or sorbitol. Lactic acid levels partly followed the same pattern. The consumption of erythritol was generally associated with significantly (p<0.05) lower counts of salivary and plaque mutans streptococci compared with the other groups. There was no change in salivary Lactobacillus levels. CONCLUSION Three-year consumption of erythritol-containing candies by initially 7- to 8-year old children was associated with reduced plaque growth, lower levels of plaque acetic acid and propionic acid, and reduced oral counts of mutans streptococci compared with the consumption of xylitol or sorbitol candies.


Caries Research | 2016

Long-Term Effect of Erythritol on Dental Caries Development during Childhood: A Posttreatment Survival Analysis.

Gwen Falony; Sisko Honkala; Riina Runnel; Jana Olak; Rita Nõmmela; Silvia Russak; Mare Saag; Pirkko-Liisa Mäkinen; Kauko K. Mäkinen; Tero Vahlberg; Eino Honkala

Objective: To assess the effect of daily consumption of erythritol, xylitol, and sorbitol candies on caries development in mixed dentition during a 3-year intervention and 3 years after the intervention. Methods: 485 Estonian first- and second-grade primary school children participated. Children were randomly allocated to an erythritol, xylitol, or sorbitol (control) group. Polyol-containing candies were administered on school days with a daily polyol consumption of 3 × 2.5 g. Yearly, caries development was assessed by calibrated dentists using the ICDAS criteria. Six years after initiation of the study and 3 years after cessation of daily polyol consumption, 420 participants were re-examined to identify potential long-term effects of polyol consumption. Survival curves were generated at the end of the intervention period and 3 years after intervention. The model included age of the subjects, schools, tooth surface ages and years of surface exposure to intervention. ICDAS scoring system-based events included enamel/dentin caries development, dentin caries development, increase in caries score, and dentist intervention. Results: At the end of the intervention, time to enamel/dentin caries development, dentin caries development, increase in caries score, and dentist intervention were significantly longer in the erythritol group as compared to the sorbitol group. Except for increase in caries score, all effects persisted 3 years after cessation of daily polyol consumption. Conclusions: A caries-preventive effect of 3-year erythritol consumption as compared to sorbitol was established in children with mixed dentition. The effect persisted up to 3 years after the end of the intervention.


Acta Odontologica Scandinavica | 2013

Caries experience in the permanent dentition among first- and second-grade schoolchildren in southeastern Estonia

Riina Runnel; Sisko Honkala; Eino Honkala; Jana Olak; Rita Nõmmela; Tero Vahlberg; Kauko K. Mäkinen; Mare Saag

Abstract Objective. This study aims to assess the caries experience among first- and second-grade children in the elementary schools of southeastern Estonia. Materials and methods. A representative sample of 485 children was studied. The mean age of children in the first grade was 7.8 years (SD = 0.35) and in the second grade 8.8 years (0.38). The clinical examinations using ICDAS criteria were completed by four calibrated examiners. The inter- and intra-examiner consistency of the examiners was high (surface and tooth-based kappa >0.9). Results. The mean caries experience of dentinal caries lesions was 0.8 (D4–6MFT) and 1.6 (D4–6MFS) among the first graders and 1.1 (D4–6MFT) and 1.6 (D4–6MFS) among the second graders. The mean caries enamel lesions among the first graders was 1.6 (D1–3T) and 2.2 (D1–3S) and among the second graders 2.1 and 3.0, respectively. The most affected surfaces were the occlusal surfaces of the lower first molars. The prevalence of sealants was very low—only 2.4% of the first molars were sealed among the first graders and 3.9% among the second graders. There were no statistically significant differences in caries experience or in the provision of restorative treatment between the schools. Conclusions. Caries experience is high in southeastern Estonia. Preventive programs are urgently needed.


European Archives of Paediatric Dentistry | 2012

Caries prevention with xylitol lozenges in children related to maternal anxiety. A demonstration project.

Jana Olak; Mare Saag; T. Vahlberg; Eva Söderling; Sára Karjalainen

AIM: This was to compare the effect of a prevention program between children of anxious and non-anxious mothers. METHODS: Mothers (n=120) with high and low dental anxiety scores (DAS≥15 and DAS ≤8, respectively), and with high levels of mutans streptococci (≥105cfu/mL) were recruited at a maternity clinic of Tartu, Estonia. Two groups: 30 highly anxious, and 30 non-anxious mothers used xylitol (6 g/day) for 33 months and a non-treatment group of 60 mothers, both highly and low anxious (30 in each sub-group), acted as controls. All mothers were interviewed for oral health habits and education, and their dental health was examined. Due to discontinued participation 75% of the children (n=90) were examined at 2 and at 3 years of age. RESULTS: Anxious mothers brushed less frequently (p=0.014), had a longer time since their last dental visit (p<0.0001), and a lower level of education (p<0.0001) than their non-anxious counterparts. However, maternal anxiety had no effect on children’s dental health, contrary to the caries prevention program which was effective both at 2 and at 3 years of age (p<0.01; OR 6.6, 1.8–25.0 and OR 3.9, CI 1.5–10.0, respectively). CONCLUSION: Children benefited from the caries prevention program, irrespective of maternal anxiety.


Acta Odontologica Scandinavica | 1998

Polyol-combinant saliva stimulants: a 4-month pilot study in young adults

Kauko K. Mäkinen; Jana Olak; Silvia Russak; Mare Saag; Taavo Seedre; Ruth Vasar; Tiiu Vihalemm; Marika Mikelsaar; Pirkko-Liisa Mäkinen

Several studies indicate that xylitol (X) consumption is associated with certain biochemical changes in dental plaque and whole saliva. In making X-containing saliva stimulants more cost-effective and palatable, manufacturers may use maltitol syrup (MS, which normally contains some sorbitol and higher polyols) or polydextrose (PD, a polysaccharide molecule with a mass > 22 kDa) as bulking agents. Combinations of X with MS and PD have not been tested regarding their salivary effects. One hundred and eighty-eight young subjects (mean age, 22 years) of both sexes were divided into three groups of equal size for a 4-month study. The subjects in one group used X-MS dragees (in 7 daily episodes; 8 g X per day), while the subjects in another group used X-PD dragées in as many daily episodes (8 g X per day). Subjects in the third (comparison) group did not receive saliva stimulants. Paraffin-stimulated whole saliva samples were collected at baseline, after 2 months, and at endpoint. The usage of X-MS was associated with a significant (P < 0.05) reduction in the salivary sucrase activity. After 4 months, the activity of enzymes hydrolyzing N(alpha)-benzoyl-DL-arginyl-p-nitroaniline was significantly reduced in all groups, while the levels of free sialic acid were reduced in group X-PD only (P < 0.05). These salivary changes most likely reflected microbial shifts in the oral cavity and suggest that information from saliva studies may be of avail when deciding which bulking agents should be used in xylitol-based saliva stimulants.


The Epma Journal | 2014

Impact of mothers’ health attitudes on dental health of their children

Mare Saag; Jana Olak

Dental caries is a common well-known multifactorial disease which affects most of the people. Parents can be the main factor in avoiding dental caries in their children. The level and the time of acquisition of mutans streptococci (MS) in infants is important, since caries risk in permanent dentition may be dependent on early colonization with MS. Parents’ behaviour can impact their children’s oral health habits. The dietary habits are very important: daily consumption of sugar containing drinks, especially during night, and frequent snacking are factors predisposing to the development of early childhood caries. Dental fear is one of the important factors influencing dental health of children. The relationship between dental anxiety and poor oral health is mediated by poor oral health habits and irregular dental visits. Maternal dental anxiety is strongly correlated with children’s anxiety. Mothers’ dental fear manifests as poor dental health and poor oral hygiene of themselves and their children. Dentally anxious mothers brushed their teeth and visited the dentist less frequently than non-anxious mothers. The child’s general fear of dentistry correlated with maternal (p=0.004) and paternal (p=0.005) dental fear. Comparing children’s dental health and fear of dentistry, it was found that dental health indices, like dmft/DMFT and dt/DT were strongly associated with children’s general fear of dentistry (p=0.017 and p=0.005, respectively), and with their fear of invasive (p=0.025 and p=0.001, respectively) and dt/DT with non-invasive procedures (p=0.004). Health education of mothers and simple preventive measures used by them reduce the risk of caries in their children. Xylitol candies, used by the mothers of toddlers, daily with adequate frequency, quantity and length of the time during eruption of primary teeth reduce the level of transmission of MS from mothers to their children. The reduced early colonization of children’s teeth with MS will manifest as improved dental health and reduced caries experience.


The Epma Journal | 2018

The influence of mothers’ oral health behaviour and perception thereof on the dental health of their children

Jana Olak; Minh Son Nguyen; Thuy Trang Nguyen; Bui Bao Tien Nguyen; Mare Saag

ObjectiveThe study aims to investigate how mothers’ oral health behaviour and perception thereof influence the dental health in their children.MethodsA total of 556 Vietnamese mother–child pairs participated in the current study. Mothers self-reported their oral status and oral health behaviour and perception. Dental caries of the children were examined using the index of decayed, missing, and filled teeth. The Dental Anxiety Scale instrument was used to assess the dental anxiety level in mothers and children.ResultsAmong mothers, 41.3% had gingival bleeding, 40% perceived their dentition and gingival status to be at a good level, 68% brushed their teeth more than twice a day, and 17% had never visited a dentist. Mothers’ oral health behaviour and their perception thereof were positively correlated with their frequency of dental visits (r = (0.105–0.221), p < 0.001) and negatively correlated with dental anxiety (r = (− 0.149– − 0.105), p < 0.05).Caries-free children were positively correlated with mothers having more than 20 teeth (r = 0.085, p < 0.05). Positive correlations between mothers and children were found in terms of frequency of fresh fruits consumption (r = 0.090, p < 0.05), drinking sweet beverages (r = 0.072, p < 0.05), and dental anxiety (r = 0.183, p < 0.001).ConclusionsMaternal oral health was significantly associated with dental health of their children. Not only did maternal dental anxiety influence oral health of mothers but it was also a concomitant factor in the development of children’s dental anxiety. The education programme on mothers’ oral health-related knowledge can be a target for improvement of the oral health of mothers and children.

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Tero Vahlberg

Turku University Hospital

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