Survival of endodontically treated teeth in public dental service in Northern Finland: a practise-based register study.

OBJECTIVE: The aim of this study was to explore the factors associated with the survival of root canal treated teeth in a practise-based study setting in a 5-year period. MATERIAL AND METHODS: This retrospective study used data from the electronic patient registration system of the public dental services of the City of Oulu, Finland. The inclusion criteria for this study were patients aged ≥ 20 years who had root canal treatment (RCT) that was initiated in 2014. One RCT per patient was included in the study. A total of 713 patients met the inclusion criteria. The outcome variable for this study was the extraction of the RCT tooth during the 5-year period. Explanatory variables included age, diagnosis, tooth type (incisive, canine, premolar, molar), RCT technique (manual, motorized), time from RCT initiation to final restoration and type of final restoration (composite, glass ionomer, fixed dental prosthesis). To evaluate the association between the outcome variable and explanatory variables, Cox regression analyses were performed. RESULTS: The overall survival rate was 91%. The middle-aged (40-59-years-old) and the oldest (60 and older) patients had a two-fold risk of extraction compared to younger (20-40-years-old) patients. Similarly, a short length of time from RCT initiation to final restoration (0-14 days) resulted in a nearly three times higher risk of extraction compared to a longer period (≥ 90 days). CONCLUSIONS: The 5-year survival rate of RCTs seems high. Extractions were more common among patients over 40 years of age and if the RCT was completed shortly after its initiation.

Genome-wide association study identifies novel caries-associated loci showing sex-specificity-A study on the Northern Finland Birth Cohort 1966.

A genome-wide association study was performed in sex-stratified groups representing three different caries phenotypes among adults. The study sample consisted of 46-year-old participants of the Northern Finland Birth Cohort 1966 study (n = 1481). The phenotypes for analyses were the dentin caries phenotype (persons having at least one tooth with dentin caries lesion), and the enamel caries phenotype (those having teeth with more than 10 enamel caries lesions), while the control group had <10 enamel caries lesions and no teeth with dentin caries, respectively. A third phenotype dubbed the caries severity phenotype had a below-average number of teeth with initial lesions and at least one extensive dentin caries lesion; their controls had an above-average number of teeth with initial caries lesions and no teeth with extensive dentin caries lesions. All analyses were performed for the whole group and for sex-stratified subgroups. In females, loci in chromosomes 2, 5, and 15 showed a statistically significant association with caries severity. In males, there was a novel association between chromosome 5 and dentin caries. The results of this study may suggest a genetic background of caries among adults. In the future, the detection of genetic predisposing variants may allow the identification of patients at risk for caries, even in the absence of behavioral and environmental risk factors.

Association of Enamel Caries Lesions with Oral Hygiene and DMFT among Adults.

The aim of this study was to evaluate the prevalence of enamel caries lesions and their association with tooth brushing frequency, tooth brushing quality, and past caries experience among Finnish adults. The study population comprised 46-year-old members of the Northern Finland Birth Cohort 1966 (n = 1,961). Caries lesions were examined and recorded at surface level using the International Caries Detection and Assessment System (ICDAS). The cut-off point for enamel caries was set to ICDAS score 3. The cut-off point for brushing frequency was twice daily. Visible plaque on buccal tooth surfaces represented brushing quality. Using enamel caries lesions (ICDAS1-3) as a dependent variable, an adjusted logistic regression model was conducted to investigate the association with gender, brushing frequency, visible plaque, dentin caries lesions (ICDAS4-6), teeth with restorations, extractions and fractures. Almost all participants (99%) had enamel and 40% had dentin caries lesions; the mean number of teeth with enamel caries lesions was 13.8 (SD 4.6). According to the adjusted logistic regression model, the high prevalence of ICDAS1-3 lesions was associated with having visible plaque on more than 20% of teeth and having more than 13 restored teeth. In conclusion, the prevalence of enamel caries lesions is high among the Finnish adult population. The results of this study suggest that in addition to tooth brushing frequency, the presence of visible plaque seems to be critical when evaluating the association between tooth brushing and enamel caries.

Association of indirect restorations with past caries history and present need for restorative treatment in the Northern Finland Birth Cohort 1966.

OBJECTIVES: The objective of this study is to examine the prevalence of indirect restorations and their association with past caries history and present need for restorative treatment among adults in Northern Finland. MATERIALS AND METHODS: The study population was a subsample of the Northern Finland Birth Cohort 1966 (n = 1961). The oral examinations were performed in 2012-2013. Indirect restorations (inlays/onlays and single crowns) were recorded tooth wise. Caries history was described with the sum of decayed, missing, and filled teeth (DMF). Caries was assessed using the International Caries Detection and Assessment System (ICDAS). The score of 4 was used as the cut off point for visible decay. Present need for restorative treatment was calculated by summing the decayed (D) and fractured (Fr) teeth. Need for restorative treatment was dichotomized to low [(D + Fr) ≤ 1] and high [(D + Fr) > 1]. RESULTS: Altogether, 7.8% of the study population had indirect restorations. The prevalence of indirect restorations did not differ within DMF (p = 0.925), but it was higher among the subjects with a low need for restorative treatment (p < 0.001). CONCLUSIONS: Indirect restorations were rare in the adult population and found mainly among the subjects with a low need for restorative treatment. CLINICAL RELEVANCE: The results of the study can encourage dentists to consider more often indirect restorations for subjects with a need for restorative treatment.

Association of depressiveness with chronic facial pain: a longitudinal study.

OBJECTIVE: Depression and pain are often co-morbid. Temporomandibular disorders (TMD) include facial pain as one main symptom. Reports are lacking on the association between chronic facial pain and earlier depressiveness. The aim of the study was to investigate whether depressiveness increases the risk for chronic facial pain in a longitudinal population-based study. MATERIALS AND METHODS: Subjects included in the Northern Finland Birth Cohort 1966 (n = 5696) answered a questionnaire on facial pain and depressiveness using the Symptom Checklist-25 depression sub-scale at the age of 31 years. In addition, reported depression diagnosed by a doctor was enquired about. Three years later a sub-sample of the cohort, including 63 cases with chronic facial pain and 85 pain-free controls, was formed based on the question concerning facial pain. RESULTS: Of the chronic facial pain cases 17.5% and of the pain-free controls 7.1% were depressive 3 years earlier at baseline (p = 0.050, χ(2) test, crude OR = 2.8, 95% CI = 1.0-8.0). Of the chronic facial pain cases 6.3% and of the pain-free controls 1.2% reported having had diagnosed depression (p = 0.085, crude OR = 5.7, 95% CI = 0.6-52.2). After adjusting the gender, the association between depressiveness reported at the baseline and chronic facial pain was significant (OR = 4.2, 95% CI = 1.1-16.2). When widespread pain was included in the analysis, the association was not significant. CONCLUSIONS: Depressiveness increases the risk for chronic facial pain in a 3-year follow-up. This association seems to be mediated through widespread pain.

A Hands-On Exercise on Caries Diagnostics among Dental Students-A Qualitative Study.

According to current care practices, the aim is to prevent the onset of caries lesions and to stop the progression of incipient lesions. A visual lesion assessment system, International Caries Detection and Assessment System (ICDAS), has been developed to promote reliability and repeatability of assessment of different stage caries lesions. The aims of this study were to evaluate the experiences of a hands-on exercise with authentic teeth as an adjunct to lecturing among third-year dental students and to evaluate the learning process during the hands-on exercise measured by qualitative (inductive content) analysis of the given feedback. In 2018, 51 third-year dental students at the University of Oulu, Finland, participated in a hands-on exercise on caries detection, where they assessed the depth and activity of lesions in extracted teeth using the ICDAS classification. After the lecture, students evaluated the exercise, giving feedback according to five given topics, three of which were analyzed using inductive content analysis. The exercise was considered useful and necessary but, overall, also challenging. The diverse activities and materials, as well as observational methods, promoted learning. The classification of lesions, the diagnostic methods, and the fact that there was not enough time to adopt things during the exercise were found to be challenging. For developing the exercise, the students suggested that more time should be scheduled for it and there should be more individual teaching. This qualitative study showed that, despite the challenge in caries diagnostics, dental students perceive the hands-on exercise as both a communal and individual learning experience.