The relation of temporomandibular disorders with oral health-related quality of life in the Northern Finland Birth Cohort 1966.

OBJECTIVE: This study aimed to evaluate the association between temporomandibular disorders (TMD) and oral health-related quality of life (OHRQoL) in an adult population. METHODS: The data included 1,768 adults 46 years of age in the Northern Finland Birth Cohort 1966 (NFBC1966) study. The symptoms, signs and diagnoses of TMD were assessed using a modified protocol of the Diagnostic Criteria for TMD (DC/TMD) and validated questionnaires. OHRQoL was measured using the Oral Health Impact Profile (OHIP-14). Associations of TMD and OHRQoL were evaluated with χ2 -test and Fisher's exact test. RESULTS: In females, pain-related TMD signs and diagnoses associated significantly with prevalence of OHIP total and all dimensions, whereas in joint-related TMD, psychological dimensions showed the strongest association. Males with pain- or joint-related TMD, the most impaired dimension was physical pain. CONCLUSION: Pain-related TMD seems to associate more strongly with lower OHRQoL than joint-related TMD especially in females.

Prevalence of sagittal molar and canine relationships, asymmetries and midline shift in relation to temporomandibular disorders (TMD) in a Finnish adult population.

OBJECTIVE: To examine the prevalence of sagittal relationships, asymmetries and midline shift, and their associations with temporomandibular disorders (TMD) in the Northern Finland Birth Cohort 1966 (NFBC1966). MATERIALS AND METHODS: 1845 subjects participated in a clinical examination at the age of 46. Occlusal measurements were performed using 3D models. Symptoms of TMD were screened using validated questions, and signs and diagnoses of TMD were assessed using a modified protocol of the Diagnostic Criteria for TMD (DC/TMD) and questionnaires. Associations between variables of occlusion and TMD were evaluated with χ2-test and Fisher's exact test and using logistic regression analyses, adjusted for self-reported general health, mental health, bruxism, and rheumatoid arthritis. RESULTS: The most common sagittal relationships were Class I and normal canine relationship. Half-cusp Class II and post-normal canine relationship were more frequent in females, and Class III and pre-normal canine relationship in males. Deviations from normal cuspid or molar relationships showed a weak but statistically significant association with TMD, especially in females. Half-cusp Class II and Class II relationships were more frequent in relation to joint-related TMD signs and diagnoses while missing canines were associated with pain-related TMD diagnoses. CONCLUSIONS: The present study findings gave some indications that canine relationships are associated with pain-related TMD, whereas Angle II sagittal occlusal relations may associate with joint-related TMD. Occlusal characteristics should therefore be taken into account as one possible associating factor in subjects with TMD.

Associations of sagittal malocclusions with dental arch characteristics and crowding in Northern Finland Birth Cohort 1966.

OBJECTIVE: To analyse the associations between the widths and forms of dental arches, malocclusions and crowding in middle-aged adult population. MATERIALS AND METHODS: The study material is part of the Northern Finland Birth Cohort 1966 (NFBC1966); the subjects were examined at the age of 46 years. A total of 781 adults with full dentition and no orthodontic treatment history were included. Overjet, overbite, cross-bite and scissor bite were examined during clinical examination. The widths and forms of dental arches, molar relationships and crowding were measured using three-dimensional (3D) dental models. RESULTS: Dental arches were significantly larger in males than in females. Class II (CII) occlusion and increased overjet (≥6 mm) were associated with narrow maxilla (P < .001, P < .05 respectively). Subjects with lateral cross-bite had significantly narrower maxilla and wider mandible (P < .05) than subjects with normal lateral occlusion. In subjects with CII occlusion, square or tapered maxilla and tapered or ovoid mandible were significantly more frequent compared to subjects with Class I (CI) occlusion (P < .05). CII occlusion was significantly associated with crowding in the maxilla (P < .01). CONCLUSION: Narrow and tapered-shaped maxilla was related to CII occlusion, which was associated with dental crowding in the maxilla. Malocclusions were more likely to be found together with other malocclusions than alone.

Epithelial salivary gland tumors in two distant geographical locations, Finland (Helsinki and Oulu) and Israel (Tel Aviv): a 10-year retrospective comparative study of 2,218 cases.

Salivary gland tumors (SGTs) of epithelial origin are relatively rare, and worldwide reports show considerable variations in their epidemiology. The aim of this study was to examine, for the first time, the records of SGTs from two very distant geographical locations, Finland (two medical centers) and Israel (one medical center) between 1999 and 2008, based exclusively on the 2005 WHO classification of head and neck tumors, and to compare those data to the other available (single-center) studies that used the same classification. A total of 2,218 benign and malignant tumors diagnosed in the three centers were analyzed. Differences in classification of the tumors were found between the two geographical locations as well as between the two centers from Finland. There was a higher ratio of benign-to-malignant SGTs in the Finnish centers (5.4:1 and 7:1) compared to the Israeli center (2:1), a higher frequency of tumors of minor salivary glands in the Israeli center (34%) than in the Finnish centers (4 and 11%), and a higher frequency of malignant SGTs in the minor salivary glands in Israel (64.5%) than in Finland (10.9 and 27%). The diversity of these multicenter data are compatible with reports from different parts of the world. We conclude that conducting epidemiologic surveys based on the latest WHO classification provides clinicopathologic correlations on SGTs that seem to be characteristic even in small geographical regions.