Fourier-transform infrared study on effects of ageing, oestrogen level and altered dietary loading on rat mandibular condylar cartilage.

OBJECTIVE: Mandibular condylar cartilage (MCC) of the rat was examined with the Fourier-transform infrared (FITR) spectroscopic imaging to study the effects of ageing, oestrogen level and altered dietary loading on the structure of MCC. MATERIALS AND METHODS: The Sprague-Dawley rats (n = 96) aged 5 and 14 months were divided into 12 subgroups according to age, oestrogen status (ovariectomized [OVX], non-ovariectomized [non-OVX)]) and diet (hard, normal, soft). Specimens of the MCC were examined with FTIR spectroscopic imaging to quantify the distribution of collagens and proteoglycans. MCC was divided sagittally into three segments: anterior, most superior and posterior. From each segment, the collagen and proteoglycan contents at different depths of cartilage were statistically compared between the groups using an N-way analysis of variance (ANOVA). RESULTS: The amount of collagen content was significantly associated with old age in the deep layer of the anterior segment and in the middle layer of the posterior segment of MCC. In the deep layer of the most superior segment, the collagen content also increased with ageing. The amount of proteoglycan content increased significantly when dietary loading increased, and the oestrogen level decreased in the deep layer of the most superior segment of MCC. CONCLUSION: Ageing, oestrogen level and altered dietary loading have a significant effect on the location and content of collagens and proteoglycans of rat MCC. Ageing significantly increased the amount of collagen content in the superior and posterior segments, being highest in the older soft-diet rats. Decreased oestrogen levels and increased dietary loading increased the amount of proteoglycan content.

Association of climacterium with temporomandibular disorders at the age of 46 years - a cross-sectional study.

OBJECTIVE: Hormonal factors have been suggested to contribute to female dominance among subjects with temporomandibular disorders (TMD). Aim of the study was to examine the association of climacteric status with TMD amongst female participants in the Northern Finland Birth Cohort (NFBC) 1966 at 46 years of age. MATERIAL AND METHODS: Among female subjects in NFBC1966, climacteric status was determined based on menstrual anamnesis and measurement of blood follicle-stimulating hormone (FSH) levels. Women with FSH > 25 IU/L and amenorrhoea > 4 months were defined as climacteric (case group, n = 71); women not diagnosed as climacteric were defined as preclimacteric (control group, n = 656). Differences between cases and controls were evaluated on self-reported TMD pain, clinical TMD signs and TMD diagnoses using modified Diagnostic Criteria for TMD (DC/TMD) protocol. Crosstabulation and logistic regression models were used to analyse differences between cases and controls. RESULTS: Compared to preclimacteric women, climacteric women had significantly more often pain on palpation in temporomandibular joints (TMJs) (OR = 2.64, 95% CI 1.12-6.21, p= .026) and more crepitus in TMJs (OR = 2.92, 95% CI 1.13-7.56, p= .027). Degenerative joint disease diagnoses were more common in climacteric than preclimacteric women (OR = 2.27, 95% CI 1.05-4.91, p= .037). Differences were statistically significant after adjusting for confounding factors (body mass index (BMI), smoking, parity). No statistically significant differences in self-reported TMD pain were noted between groups. CONCLUSION: Among females at the age of 46 years, climacterium seems associated with TMD by increasing pain on palpation in TMJs, subjective symptoms, and clinical signs indicating degenerative changes in TMJs when using DC/TMD.

Flexural and Surface Properties of PMMA Denture Base Material Modified with Thymoquinone as an Antifungal Agent.

PURPOSE: To evaluate the effect of addition of different concentrations of thymoquinone (TQ) on the flexural strength, elastic modulus, surface roughness, and hardness of PMMA denture base material. MATERIALS AND METHODS: A total of 160 rectangular specimens were prepared from heat-polymerized acrylic resin, with dimensions of 65 × 10 × 2.5 mm3 for flexural strength testing and 10 × 20 × 3 mm3 for surface property testing. The specimens were divided into eight groups of 20 specimens: one control group without addition of TQ and seven test groups prepared by adding TQ to acrylic powder in concentrations of 0.5, 1, 1.5, 2, 2.5, 3, and 5 wt%. The polymer was added to the monomer before being mixed, packed, and processed using the conventional water bath method. A universal testing machine was used to measure flexural strength and elastic modulus. A profilometer and a Vickers hardness tester were used to measure surface roughness and hardness, respectively. One-way ANOVA and the Tukey-Kramer multiple-comparison test were used for statistical analysis, with statistical significance at p ≤ 0.05. RESULTS: Addition of TQ to PMMA denture base material significantly decreased flexural strength and elastic modulus at high concentrations (p < 0.01), while no significant differences were observed at low concentrations (0.5%, 1% TQ) in comparison with the control group. At high TQ concentrations, surface roughness increased while hardness decreased (p < 0.0001), and no significant differences were observed at low concentrations (0.5%, 1% TQ) in comparison with the control group. The most favorable addition values were 0.5% and 1% TQ in all TQ groups. CONCLUSIONS: Addition of TQ did not affect the flexural and surface properties of PMMA denture base material at low concentrations (0.5%, 1% TQ) and could be incorporated into PMMA denture base material as an antifungal agent.

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 risk factors with temporomandibular disorders in the Northern Finland Birth Cohort 1966.

OBJECTIVE: To investigate the association between risk factors and pain-related symptoms and clinical signs of temporomandibular disorders (TMD) in Northern Finland Birth Cohort (NFBC) 1966. MATERIAL AND METHODS: A total of 1962 subjects (1050 women, 912 men) attended the follow-up study. The questionnaires included the subjects' background information concerning living conditions and general health, socioeconomic factors, and dental health. The clinical examination was performed using the modified protocol of Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) presented at the International Association for Dental Research (IADR) Conference in 2010. Cross-tabulation, a chi-square test and Fisher's exact test were used to analyze differences between groups. RESULTS: Female gender showed statistically significant association with symptoms and signs of TMD, while marital status, living conditions, and socioeconomic group showed no association. A strong association was found between self-reported health condition as well as general health problems [i.e. depression, migraine, fibromyalgia (FM), gastrointestinal diseases] and TMD pain-related symptoms and pain on palpation in the masticatory muscles and TMJs. CONCLUSION: In conclusion, general health problems and female gender had a strong association with pain-related symptoms and clinical signs of TMD. These findings are important to take into account when diagnosing and treating TMD patients. Conversely to earlier presented results, no statistically significant association was shown here between marital status, living conditions or socioeconomic group and pain-related symptoms and clinical signs of TMD.

Outcome of zirconia partial fixed dental prostheses made by predoctoral dental students: A clinical retrospective study after 3 to 7 years of clinical service.

STATEMENT OF PROBLEM: Zirconia has an established role in fixed prosthodontics, especially for single crowns. Whether it is durable enough for fixed dental prostheses (FDPs) in the long term is yet unclear. PURPOSE: The purpose of this retrospective study was to evaluate the outcome of FDPs made by predoctoral students after 3 to 7 years of clinical service. MATERIAL AND METHODS: A total of 102 patients received 120 zirconia FDPs (range, 3-12 units; mean, 4.5 units) between 2007 and 2010. Materials used were Zirkonzahn Zirconia (Zirkonzahn), NobelProcera Zirconia (Nobel Biocare), and Prettau Zirconia (Zirkonzahn). Veneering porcelain was hand-layered on Zirkonzahn Zirconia (GC Initial Zr; GC Europe) and Nobel Procera Zirconia (VITA VM 9; VITA Zahnfabrik). Prettau Zirconia was monolithic and had no veneering porcelain. Success and survival rates were calculated using Kaplan-Meier survival analysis. Ethics approval was obtained from the Ethical Committee of the Northern Ostrobothnia Hospital District (100/2013). RESULTS: The 76 participants examined (75%) had received 88 zirconia FDPs. The mean follow-up period was 4.9 years (range, 3-7 years). The most common complication was chipping of the veneering porcelain in 13 of 88 FDPs (14.7%). The success rate of the zirconia-based partial FDPs after 4.9 years was 89%, and the survival rate was 100%. CONCLUSIONS: The success rate of the zirconia-based partial FDPs after 4.9 years was 89%, and the survival rate was 100%.

Outcome of zirconia single crowns made by predoctoral dental students: a clinical retrospective study after 2 to 6 years of clinical service.

STATEMENT OF PROBLEM: Zirconia has established its role as a reliable ceramic material for fixed prostheses. PURPOSE: The purpose of this retrospective study was to evaluate the outcome of zirconia single crowns made by predoctoral students after 2 to 6 years of clinical service. MATERIAL AND METHODS: A cohort of 88 patients treated with zirconia single crowns (mean 3 crowns per patient, range 1 to 12 crowns) from 2007 to 2010 by predoctoral dental students was identified. The patients were invited to attend a clinical examination. RESULTS: Sixty-six participants (75%) took part in the clinical follow-up (30 women and 36 men; mean age 60.4 years, range 19 to 81 years). Altogether, 190 teeth with single crowns were examined, and the mean follow-up time was 3.88 years (1.85 to 6.04 years). The most common complications were chipping of veneering porcelain (4%) and loss of cementation (4%). The success rate of the zirconia single crowns after 2 to 6 years was 80% and the survival rate 89%. CONCLUSIONS: Zirconia crowns can be successfully used in predoctoral dental education. The success rate of zirconia single crowns after 2 to 6 years was 80% and the survival rate was 89%, in accordance with previous studies.

Veneered zirconia crowns as abutment teeth for partial removable dental prostheses: a clinical 4-year retrospective study.

STATEMENT OF PROBLEM: The mechanical properties of zirconia suggest that it might serve as a material for abutment crowns for partial removable dental prostheses (RDPs). Only limited clinical evidence is available for the use of ceramics as abutment crowns. PURPOSE: The purpose of this retrospective clinical study was to evaluate the outcome of veneered zirconia single crowns in abutment teeth for RPDs in participants treated by predoctoral students. MATERIAL AND METHODS: Thirty-seven veneered zirconia single crowns in 17 participants (9 men and 8 women; mean age 62.5 years) were prepared as abutment teeth for a clasp-retained RDP with a metal framework: 22 crowns with an occlusal rest seat and 15 crowns with both an occlusal rest seat and retentive clasps. The mean follow-up time was 4.2 years (2.9 to 5.4 years). In a clinical examination, the anatomic form of the crown, marginal fidelity (the border between the crown and the tooth was felt with an explorer), wear of the ceramic surface in the rest seat, and fracture of the veneering porcelain were examined and assessed as good, acceptable, or unacceptable. The retention and stability of the RDPs were recorded as good, moderate, or poor. RESULTS: The complications found were fracture of the veneering porcelain (11%) and fracture of the occlusal rest seat (3%). Wear of porcelain at the occlusal contact point was found in 24% of the zirconia single crowns. Wear of the ceramic surfaces of the rest seats for the RDPs was not found. The retention was good in all RDPs. The stability was good in 73% and moderate in 23% of the RDPs. CONCLUSIONS: Veneered zirconia single crowns are suitable in abutment teeth for RDPs with a metal framework. Fracture in the veneering porcelain remains a problem with veneered zirconia, although the zirconia surface in the rest seats for RDPs showed no wear.

Early complications and short-term failures of zirconia single crowns and partial fixed dental prostheses.

STATEMENT OF PROBLEM: Ceramic single crowns fabricated from newer materials, especially zirconia, have shown relatively high survival rates. However, early reversible complications may increase the risk of an irreversible failure later. PURPOSE: The purpose of the study was to evaluate the early complications and short-term failures of zirconia single crowns and partial fixed dental prostheses (FDPs) made by predoctoral dental students. MATERIAL AND METHODS: Data were collected from the patient records. Altogether, 264 zirconia single crowns and 120 FDPs (342 abutments and 190 pontics) were fabricated for 173 patients between 2007 and 2010. Early complications were recorded during the prosthetic treatment phase, and short-term failures were recorded during the first year in use. RESULTS: The most frequent early complications were localized gingival irritation (1.9% of single crowns and 2.5% of FDP) and postoperative tooth sensitivity (0.4% of single crowns and 3.3% of FDPs). Pulp exposure during preparation was recorded in 3 abutment teeth of the FDPs. The most frequent short-term failure was chipping of the veneering porcelain (0.8% for single crowns, 0.8% for FDPs). One crown lost cementation because of poor retention (0.4%), and 2 FDPs failed because of framework fractures (1.7%). CONCLUSIONS: The most frequent early complications were localized gingival irritation and postoperative tooth sensitivity, and the most frequent short-term failure was chipping of the veneering porcelain.

Outcome of treatment of implant-retained overdenture in patients with extreme mandibular bone resorption treated with bone grafts using a modified tent pole technique.

PURPOSE: To evaluate the outcome (prosthetic maintenance, survival of implants, patient satisfaction, and quality of life) of prosthetic treatment using an implant-retained overdenture and a modified tent pole procedure for severe mandibular resorption. MATERIAL AND METHODS: Seventeen edentulous patients (mean age, 68 yr; range, 54 to 77 yr) with severely resorbed mandibles were treated with autogenous bone grafts using a modified tent pole technique and implant overdentures. A bar was used to splint the implants and the final prostheses with implant connection were completed approximately 7 months after surgery. The mean follow-up time was 5 years (1.5 to 7.4 yr). Patients filled out the Oral Health Impact Profile-14 questionnaire concerning their oral health-related quality of life, and then panoramic radiographs were taken during clinical examination. RESULTS: The stability of the overdenture was good in 58.8% of cases and retention was good in 64.7%. The most usual prosthetic complication was loosening of the attachment component, which occurred in 7 cases (41.2%). The amount of plaque and bleeding was more remarkable on the lingual surface of the implants and less remarkable on the buccal surface. Pocket depth around the implants seemed to correspond to intraoral implantation. The radiographs depicted excellent grafted bone survival. The patients' oral health-related quality of life was found to be good after treatment. CONCLUSIONS: Implant placement with bone grafting using a modified tent pole technique enables the achievement of a good prosthetic solution and the rehabilitation of occlusion, thereby improving the functionality of the prostheses and quality of life.

Association of self-reported bruxism with temporomandibular disorders - Northern Finland Birth Cohort (NFBC) 1966 study.

OBJECTIVE: To investigate the prevalence of self-reported bruxism and its association with temporomandibular disorders (TMD). The hypothesis of the study was that self-reported bruxism is associated with TMD. METHODS: The data were gathered from 1962 subjects who participated in a field study in 2012-2013, including a questionnaire concerning bruxism and TMD symptoms as well as clinical sub-diagnoses of TMD using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Statistical method was chi-square test. Bonferroni correction was made, and a p-value of <0.003 was considered as significant. RESULTS: The prevalence of self-reported bruxism was 39.6%: 34.0% in men and 44.5% in women. Those who reported sleep bruxism (SB) or awake bruxism (AB) had significantly more pain-related TMD symptoms and signs compared to those not reporting bruxism. CONCLUSION: The prevalence of self-reported bruxism is high among middle-aged adults and is associated with TMD pain-related symptoms and signs, as well as TMD diagnoses.

Effect of estrogen and dietary loading on condylar cartilage.

AIMS: To study the effect of estrogen deficiency and altered temporomandibular joint loading on the histomorphology of condylar cartilage and on the expression of types II and X collagen and matrix metalloproteinase-3 (MMP-3). METHODS: Thirty-six female rats were divided into four groups: ovariectomized rats on a normal diet, nonovariectomized control rats on a normal diet, ovariectomized rats on a soft diet, and nonovariectomized control rats on a soft diet. Ovariectomy was performed at the age of 60 days. Repeated-measures ANOVA was used to analyze the data. RESULTS: The condylar cartilage in the ovariectomized normal diet group showed a significantly higher number of cells than in the nonovariectomized control rats (P < .001). The proportional amount of MMP-3 expression was significantly higher in the ovariectomized rats than in the nonovariectomized control rats in both diet groups (P < .001). The area covered by types II and X collagen was significantly higher in the experimental groups than in the control groups (P < .01). CONCLUSION: Condylar cartilage is sensitive to both estrogen level and dietary loading.

Outcome of implant-supported overdenture treatment--a survey of 58 patients.

OBJECTIVE: The aim of this follow-up study was to evaluate the long-term outcome of implant-supported or implant-retained mandibular overdenture treatment. MATERIAL AND METHODS: Altogether 112 patients treated with implant-supported overdentures between 1985 and 2004 were invited to the follow-up and 58 attended the clinical examination. The total amount of implants examined and still in use was 197. The average number of implants installed was three (range 2-4), and the mean length of the implants was 12 mm (range 8-21 mm). There were altogether 48 overdentures with a bar connection and 10 with a ball connection. RESULTS: The most frequent prosthetic complications were technical: loosening of the retentive mechanism (39.7%) and breakage of the matrices (5.2%). The most common peri-implant soft-tissue findings were bleeding and slight hyperplasia. The implant-supported overdentures of 19 patients (32.8%) had been renewed, while 39 patients (67.2%) still used their original overdentures, of which the oldest was 20 years old. CONCLUSION: The results of this long-term follow-up study show that the outcome of implant-supported mandibular overdenture treatment was excellent. The patients were satisfied with the treatment, regardless of the attachment type used. Removable overdentures are more easy to clean and can be cleaned outside the patient's mouth, whereas fixed-implant full-arch dentures in the edentulous mandible require much more time-consuming hygiene. This kind of overdenture treatment is suitable also in the elderly, even though their ability to practice appropriate oral hygiene might be decreased.

The comparison of outcomes of surgically treated bilateral temporomandibular joint disorder in different groups: a retrospective study.

OBJECTIVES: The main purpose of this study was to determine the prognosis and outcomes of the patients with bilateral temporomandibular disorder which underwent bilateral temporomandibular joint surgery in a consecutive number of patients in a retrospective study. STUDY DESIGN: Sixty five patients with 130 bilateral TMJ were included the study with the selection from consecutive 256 TMJ patients who were treated with open surgery who do not respond to conservative treatment. 65 patients were divided in to 3 main groups according to the clinical diagnosis of bilateral TMJ site. In the first group comprised 29 patients with 48 TMJ, the clinical diagnosis was bilaterally presence of anterior disc displacement with reduction (ADDR). In the second group comprised 19 patients with 26 TMJ, bilateral presence of TMD consisted of anterior disc displacement without reduction (ADDNR) on both site. In the third group comprised 27 patients with 46 TMJ, bilaterally presence of TMD consist of ADDR on one site and ADDNR on another site. The patients in three different groups were operated either high condylectomy alone or high condylectomy with additional surgical procedures. RESULTS: In the evaluation of pain relief, clicking, crepitation, headache, marked improvement was determined in all groups, but it was statistically insignificant in the comparison of 3 groups. Slight increase in maximal mouth opening was determined in the mean values of the 3 groups and also in the comparison of 3 groups it was not statistically significant. CONCLUSIONS: These similar succesfull outcomes of bilateral TMD with the respect of TMJ surgical procedures were obtained in 3 main groups although different diagnosis on the patients' groups was present.

Occlusal characteristics in facial pain cases and controls - 12-year follow-up of the Northern Finland Birth Cohort (NFBC) 1966.

Objective: The purpose of this study was to investigate the occlusal characteristics in Finnish adults at 12-year follow-up based on the Northern Finland Birth Cohort 1966 (NFBC1966) subjects.Methods: The occlusal analyses were performed at ages 34 and 46 years of facial pain cases (n = 52) and controls (n = 49) by two different methods.Results: At 12-year follow-up, a significant decrease in upper anterior segment peer assessment rating (PAR) score was found in the controls, indicating improvement in teeth alignment. In facial pain cases, left lateral occlusal relationship and midline asymmetry were significantly decreased. Occlusal asymmetry and overjet were significantly increased. In controls, the left canine showed a more normal occlusal relationship, cuspid asymmetry was changed, and midline asymmetry was significantly decreased.Conclusion: During a 2-year period, occlusal asymmetry and overjet increased significantly in facial pain cases, while occlusal relationship showed more normal characteristics in controls.

Association of temporomandibular disorders with pain sensitivity: A cohort study.

BACKGROUND: Pain related to temporomandibular disorders (TMD) can be linked with multiple site pain (MSP), and may associate with increased pain sensitivity, more frequently among women than men. The aim of the study was to examine the associations of pressure pain threshold (PPT) and tolerance (PPTo) with TMD and associated MSP in the Northern Finland Birth Cohort 1966 (NFBC1966) study. METHODS: Altogether 1961 NFBC1966 subjects attended clinical medical and dental examination at the Institute of Dentistry, University of Oulu in 2012-2013. Clinical examinations were carried out using a modified Diagnostic Criteria for TMD protocol (DC/TMD). MSP was defined based on questions regarding body pain sites. Additionally, PPT and PPTo were assessed using algometer measurements. Mann-Whitney U-test and Tobit regression models were used to analyse associations between TMD sub-diagnoses, MSP, PPT and PPTo, stratified by sex. Further models were adjusted with anxiety and depressive symptoms, which were assessed using Hopkins Symptom Checklist-25 (HSCL-25) and two-way interaction terms. RESULTS: Among females, lower PPT and PPTo were associated with myalgia and arthralgia. Among males, lower PPT and PPTo were associated with MSP-linked TMD. Tobit regression analysis showed significantly lower PPT and PPTo values in the myalgia and arthralgia subgroups among female TMD subjects. Among females, disc displacement with reduction had an inverse association with PPT and PPTo. Among males, lower PPTo was associated with degenerative joint disease and MSP-linked TMD. CONCLUSIONS: The pain regulatory mechanisms behind TMD act differently between the genders as local TMD among females and MSP-linked TMD among males were associated with pain sensitivity. SIGNIFICANCE: The study shows that there are differences in the associations of painful TMD with pressure pain tolerance, pressure pain sensitivity and MSP between male and female subjects.

Effect of diet hardness on mandibular condylar cartilage metabolism.

AIMS: To study the effect of diet hardness on condylar cartilage thickness, extracellular matrix composition, and expression of matrix metalloproteinase (MMP) -3, -8 and tissue inhibitor of metalloproteinase-1 (TIMP-1), by using immunohistochemical and morphometric methods. METHODS: Seventy-two female Sprague Dawley rats were exposed to different dietary hardness, from soft to hard. MMP -3, -8, and TIMP-1 expression, cartilage thickness, cell count, and expression of type II collagen were studied. Analysis of variance among treatments was carried out followed by Bonferroni's comparisons test. RESULTS: The ratio of MMP-3 and TIMP-1 immunopositive cartilage cells were similar in all age groups, whereas the number of MMP-8 positive cells decreased with age. A change of diet from soft to hard caused a significant decrease in the number of MMP-3 and MMP-8 and an increase in TIMP-1 positive cells. Cartilage thickness and area of type II collagen-positive staining were significantly affected by diet hardness. CONCLUSION: The results show that a soft diet during growth increases collagenolytic activity and may increase the vulnerability of condylar cartilage.

Effect of estrogen and altered diet hardness on the expression of estrogen receptor alpha and matrix metalloproteinase-8 in rat condylar cartilage.

AIMS: To examine the effect of decreased estrogen level and altered diet hardness on condylar cartilage morphology of the rat temporomandibular joint (TMJ) and on the expression of condylar cartilage estrogen receptor alpha (ERa) and matrix metalloproteinase-8 (MMP-8). METHODS: A total of 36 female rats was divided into four groups: ovariectomized rats fed a normal diet, non-ovariectomized controls fed a normal diet, ovariectomized rats fed a soft diet, and non-ovariectomized controls fed a soft diet. Ovariectomy was performed at the age of 60 days. Seven days after the operation, the rats were sacrificed. Repeated measures ANOVA and Duncan's multiple comparison tests were used for statistical analysis. RESULTS: The ovariectomized rats had thicker cartilage layers than the controls, both in the normal diet and soft diet groups. The thinnest cartilage layers were found in the control rats fed with the soft diet. The thickness of the chondroblastic layer was significantly higher (P < .001) in the normal-diet rats than in the soft-diet rats in both ovariectomized and non-ovariectomized groups. The thickness of the proliferative layer was significantly higher (P < .001) in the ovariectomized soft-diet rats than in the soft-diet control rats. The proportional amount of ERa was statistically significantly higher (P < .001) in the condylar cartilage of the ovariectomized rats than in the non-ovariectomized control rats both in the normal- and soft-diet groups. The proportional amount of ERa was statistically significantly higher (P < .001) in the ovariectomized normal-diet rats than in the ovariectomized soft-diet rats. The proportional number of MMP-8-positive cells was statistically significantly higher (P < .001) in the condylar cartilage of ovariectomized rats fed the soft diet than in non-ovariectomized control rats fed the soft diet. Control rats fed with the normal diet had a higher proportional amount of MMP-8 positive cells than control rats fed with the soft diet (P < .05). CONCLUSION: The rat TMJ condylar cartilage is sensitive to changes in estrogen levels and altered diet hardness.

Thermographic findings related to facial pain - a survey of 40 subjects.

Objective: The purpose of this study was to assess how thermography findings relate painful symptoms and signs of temporomandibular disorders (TMD).Methods: Thermography, combined with chewing of paraffin wax, was performed on 40 subjects. The results were analyzed according to gender and pain-related TMD symptoms and clinical signs.Results: The overall temperatures after chewing were higher in TMD patients than in controls. For females, the most significant findings were the thermal increase between the relaxed state and subjects' state after chewing in temporal and temporomandibular joint (TMJ) regions. For males, all calculated parameters demonstrated a poor ability to discriminate TMD from controls.Conclusion: Thermography could be a potential tool in diagnostics of female TMD patients. The results suggest that the thermal information assessed in specific facial areas could help to discriminate TMD patients from non-TMD patients and could be used to quantify the pain associated with TMD.

Treatment outcome in patients with TMD--a survey of 123 patients referred to specialist care.

Temporomandibular disorders (TMD) are a group of functional disorders of the masticatory system. Signs and symptoms of TMD are very common in different age groups in both genders. Treatment need varies greatly, ranging from 5 to 27% of the population. The treatment of TMD patients is generally initiated using reversible conservative methods and if necessary, irreversible and surgical methods are used. Altogether 123 patients (93 females, 30 males, mean age 39 years, range 12 to 72 years) were referred to the Oral and Maxillofacial Department of Oulu University Hospital between the years 2005 and 2008. The treatment outcome was evaluated using the anamnestic and clinical dysfunction indices of Helkimo, before and after treatment. The results of the study showed that the outcome of the conservative treatment methods of TMD and of surgical treatment, if needed, was beneficial, with a subjectively and clinically statistically significant decrease in signs and symptoms.