Showing papers in "Journal of Oral Rehabilitation in 2004"
TL;DR: In this paper, a new single tooth strain-gauge transducer was used in 52 healthy young adults (36 men, 16 women) with a single implant oral rehabilitation.
Abstract: SUMMARYThe assessment of bite forces on healthy single tooth appears essential for a correct quantification of the actual impact of single implant oral rehabilitations. In the present study, a new single tooth strain-gauge bite transducer was used in 52 healthy young adults (36 men, 16 women) with a
286 citations
TL;DR: Baseline roughness average was statistically similar for all groups, however, 35% carbamide peroxide produced the roughest enamel surfaces, which resulted in different staining means and enamel surface morphological alterations.
Abstract: Concern has been expressed regarding the adverse effects of peroxide-containing tooth bleaching agents on enamel surface. This study examined enamel average surface roughness before (baseline) and after an in-office bleaching protocol and investigated the influence of high concentrations of carbamide peroxide gels on its surface staining and morphology. Flat enamel surfaces were submitted to 35 and 37% carbamide peroxide or to no bleaching treatment (n = 10) and evaluated with a profilometer. Eight specimens from each group were randomly selected and immersed in a 2% methylene blue solution. Afterwards, specimens were ground into powder and prepared for the spectrophotometric analysis. Two remained specimens of each group were examined using a scanning electron microscope. Data were subjected to analysis of variance and Tukey test (P > 0.05). Baseline roughness average was statistically similar for all groups, however, 35% carbamide peroxide produced the roughest enamel surfaces. Different concentrations of carbamide peroxide produced similar staining means and enamel surface morphological alterations.
173 citations
TL;DR: Shear bond strength of composite resin to enamel that was bonded immediately after bleaching with 10, 16 and 22% CP was significantly lower than that of unbleached enamel (P < 0.05); for all three bleaching groups, when the antioxidant-treated and delayed bonding subgroups were compared with the control group, no statistically significant differences were noted.
Abstract: The purpose of this study was to comparatively investigate the effect of antioxidant treatment and delayed bonding after bleaching with three different concentrations of carbamide peroxide (CP) on the shear bond strength of composite resin to enamel. One hundred flat buccal enamel surfaces obtained from bovine incisors were divided into three bleaching groups of 10, 16 and 22% CP (n = 30) and a control group. Each bleaching group was then divided into three subgroups (n = 10). Group 1 consisted of specimens bonded immediately after bleaching. Group 2 specimens were treated with antioxidant agent, 10% sodium ascorbate, while Group 3 specimens were immersed in artificial saliva for 1 week after bleaching. Specimens in the control group were not bleached. After the specimens were bonded with Clearfil SE Bond and Clearfil AP-X, they were thermocycled and tested in shear until failure. Fracture analysis of the bonded enamel surface was performed using scanning electron microscope. The shear bond strength data was subjected to one-way analysis of variance followed by Duncan's multiple range test at a significance level of P < 0.05. Shear bond strength of composite resin to enamel that was bonded immediately after bleaching with 10, 16 and 22% CP was significantly lower than that of unbleached enamel (P < 0.05). For all three bleaching groups, when the antioxidant-treated and delayed bonding (1 week) subgroups were compared with the control group, no statistically significant differences in shear bond strength were noted (P < 0.05).
167 citations
TL;DR: The results suggest that dentures can cause a wide range of lesions of the oral mucosa, that could be prevented with follow-up to evaluate dentures and provide instructions on how to maintain oral tissues healthy.
Abstract: summary The purpose of this study was to survey the frequency of denture-related lesions of the oral mucosa in patients treated at a Brazilian dental school and to determine if the oral lesions were related to age, sex, denture type, length of denture use and denture cleaning methods. The denture-related lesions observed in this study were chronic atrophic candidiasis, chronic hyperplastic candidiasis, denture-induced fibrous inflammatory hyperplasia (FIH), traumatic ulcer, angular cheilitis and flabby ridge. The most frequent lesion, chronic atrophic candidiasis, occurred more frequently in females, in complete maxillary denture wearers, with denture use for 16–20 years. The most common method of cleaning dentures was a toothbrush and toothpaste. These results suggest that dentures can cause a wide range of lesions of the oral mucosa, that could be prevented with follow-up to evaluate dentures and provide instructions on how to maintain oral tissues healthy.
160 citations
TL;DR: In this paper, the authors used the tooth wear index (TWI) to determine the prevalence and severity of non-carious cervical lesion (NCCL) in a population from the city of Rijeka, Croatia.
Abstract: A non-carious cervical lesion (NCCL) is the loss of hard dental tissue on the neck of the tooth, most frequently located on the vestibular plane. Causal agents are diverse and mutually interrelated. In the present study all vestibular NCCL were observed and recorded by the tooth wear index (TWI). The aim of the study was to determine the prevalence and severity of NCCL. For this purpose, 18555 teeth from the permanent dentition were examined in a population from the city of Rijeka, Croatia. Subjects were divided into six age groups. The teeth with most NCCL were the lower premolars, which also had the largest percentage of higher index levels, indicating the greater severity of the lesions. The most frequent index level was 1, and the prevalence and severity of the lesions increased with age.
148 citations
TL;DR: The association of coconut soap and 0.05% sodium hypochlorite significantly reduced clinical signs of denture stomatitis, and the association of Coconut soap and0.5% sodium Hypochlorites was effective in controlling denture biofilm.
Abstract: This study evaluated the reduction of denture stomatitis and the antimicrobial activity of 0.05% sodium hypochlorite opposed to Candida albicans and Streptococcus mutans (SGM) when associated with brushing complete dentures with coconut soap. The mucosal characteristics were evaluated according to Newton's classification at baseline, after cleansing the dentures with coconut soap for 15 days in group 1 (nine patients). In the other group (19 patients) the analysis were made before and after cleansing the dentures with coconut soap and with disinfection in a soak solution of 0.05% sodium hypochlorite for 10 min during 15 days. Microbiological tests were used to isolate C. albicans and SGM. Mann-Whitney and Wilcoxon tests were used to compare the mucosal characteristics and Fisher test and McNemar test to compare C. albicans and SGM levels. Statistical analysis at the 95% confidence level (P < 0.05) showed that: (i) the association of coconut soap and 0.05% sodium hypochlorite significantly reduced clinical signs of denture stomatitis, (ii) C. albicans did not reduce in counts, (iii) SGM were reduced but not significantly and (iv) the association of coconut soap and 0.5% sodium hypochlorite was effective in controlling denture biofilm.
148 citations
TL;DR: An immersion type cleaner was found to be the most suitable cleaner because of its low abrasivity and effective removal of organic debris.
Abstract: This study evaluated the abrasiveness of four denture cleaners on the surface of denture base material and assessed their ability to remove Candida albicans. Acrylic resin discs 20 mm diameter and 2 mm thick were identically produced and polished. Four cleaners were evaluated: conventional toothpaste; toothpaste with stain remover; denture cleaning paste and an immersion type cleaner, and water were used as control. These were used at dilutions of 1:1, 1:2 and 1:3 with water. An electric toothbrush was used, and the discs cleaned to simulate 1 years' cleaning. The surface roughness of the discs were then measured, before and after cleaning, using a stylus profilometer, then inoculated with 1.2 x 10(6)C. albicans cells. The effectiveness of the denture cleaners to remove C. albicans cells was assessed following a single cleaning event. The immersion cleaner was significantly less abrasive than paste cleaners (P 0.05). Immersion and paste cleaners removed almost all recoverable C. albicans from the discs, as cleaning with water alone was less effective (P < 0.05). An immersion type cleaner was found to be the most suitable cleaner because of its low abrasivity and effective removal of organic debris.
135 citations
TL;DR: Fruit juices were shown to pose a greater erosive threat to tooth coloured materials than Coca-Cola, a finding which is similar to those concerning dentine and enamel towards these drinks.
Abstract: The interaction of tooth-coloured dental restorative materials (a conventional glass-ionomer, two resin-modified glass-ionomers and two compomers) with acidic beverages has been studied with the aim of investigating how long-term contact affects solution pH and specimen surface hardness. For each material (ChemFil Superior, ChemFlex, Vitremer Core Build-Up/Restorative, Fuji II LC, Dyract AP and F2000) disc-shaped specimens were prepared and stored in sets of six in the following storage media: 0.9% NaCl (control), Coca-Cola, apple juice and orange juice. After time intervals of 1 day, 1 week, 1 month, 3 months, 4 months, 6 months and 1 year, solution pH and Vickers Hardness Number were determined for each individual specimen. Differences were analysed by anova followed by Student-Newman-Keuls post hoc analysis. All materials were found to reduce the pH of the 0.9% NaCl, but to increase the pH of the acidic beverages. The conventional glass-ionomers dissolved completely in apple juice and orange juice, but survived in Coca-Cola, albeit with a significantly reduced hardness after 1 year. The other materials survived in apple juice and orange juice, but showed greater reductions in surface hardness in these beverages than in Coca-Cola. Fruit juices were thus shown to pose a greater erosive threat to tooth coloured materials than Coca-Cola, a finding which is similar to those concerning dentine and enamel towards these drinks.
133 citations
TL;DR: Compared with universal hybrid restorative materials, flowable composites have lower filler loading and packable resin composites did not show higher values as claimed by some manufacturers.
Abstract: The purposes of this study were to determine the weight fraction of filler in thirty-nine resin-based materials including flowable and packable composites, and to examine the morphology of the filler particles. The percentages of inorganic fillers by weight were determined by Thermogravimetric Analysis and by ashing in air technique at 900 degrees C. The size and shape of the filler particles were examined using scanning electron microscopy (SEM) after dissolution of the organic matrix. The weight fraction of inorganic fillers ranged between 41.6 and 84.6%. Wide variations were found among materials of the same category. Values found in the present study were sometimes different from those given by the manufacturers. The SEM photomicrographs showed various shapes, and sizes of inorganic fillers. Compared with universal hybrid restorative materials, flowable composites have lower filler loading and packable resin composites did not show higher values as claimed by some manufacturers. Various factors may explain the observed discrepancies between the manufacturer's data and our results. The silane treatment as well as the incorporation of organic material as part of the fillers of the composite could be responsible for those differences.
132 citations
TL;DR: The fracture strengths of stylized all-ceramic crowns manufactured using an yttrium-oxide-partially-stabilized (Y-TZP) zirconia ceramic core (Denzir) veneered with lithium disilicate glass-ceramics were evaluated and exhibited significantly higher values than those with a 0.5 mm Denzir core and than the IPS Empress 2 crowns used as reference.
Abstract: The fracture strengths of stylized all-ceramic crowns manufactured using an yttrium-oxide-partially-stabilized (Y-TZP) zirconia ceramic core (Denzir) veneered with lithium disilicate glass-ceramics ...
131 citations
TL;DR: The weights of artificial plaque on all filling materials tested were higher than those on ceramics, the highest values were measured on the glass-ionomers, and there was no correlation of the surface roughness with the number of colony-forming units of S. mutans.
Abstract: A continuous flow system was developed to evaluate the adhesion of Streptococcus mutans ATCC 25175 to filling materials (Ariston, Tetric, Dyract, Compoglass, Vitremer, Aqua Ionofil, Ketac Fil, amalgam, Galloy and ceramics as controls). Streptococcus mutans was added to saliva-coated test specimens, and a nutrient broth permanently supplied over a time period of 48 h and then the weight of plaque, the number and viability of the bacteria adhering to the materials were determined. The weights of artificial plaque on all filling materials tested were higher than those on ceramics, the highest values were measured on the glass-ionomers. The amount of plaque correlates with the surface roughness, whereas there was no correlation of the surface roughness with the number of colony-forming units (CFU) of S. mutans. The CFU of adhering S. mutans also depends on the viability of the bacteria. The plaque on Ketac Fil contained a high number of viable bacteria. The fluorides of glass-ionomers do not efficiently prevent the attachment and the viability of S. mutans.
TL;DR: It was concluded that myofascial pain patients differed from those with disc displacement, joint disorders and no TMD in relation to some psychopathological symptoms, while the last three groups presented very similar profiles.
Abstract: Psychological factors play an important role in the aetiopathogenesis of temporomandibular disorders (TMD), as demonstrated by an increase in stress, anxiety, depression and somatization in TMD patients. The aim of this work was to investigate the presence of mood and panic-agoraphobic symptoms in different groups of TMD patients by means of a spectrum approach to psychopathology. A total of 131 subjects were included in this study and TMD signs and symptoms were investigated by means of a standardized clinical examination. Two self-report questionnaires were used to evaluate mood (MOODS-SR) and panic-agoraphobic (PAS-SR) spectrum. anova and Bonferroni's post hoc test for multiple comparisons were used to compare mean scores of all TMD groups for MOODS-SR, PAS-SR and all their domains. Results revealed a significantly higher prevalence of both mood (P < 0.001) and panic-agoraphobic (P < 0.01) symptoms in myofascial pain patients than in all other diagnostic groups (TMD-free, disc displacement and joint disorders). With regard to mood spectrum, strong differences emerged for all domains evaluating depressive symptoms. As for the panic-agoraphobic spectrum, myofascial pain patients differed from the other groups for the presence of stress sensitivity, panic, separation anxiety, hypochondriac and agoraphobic symptoms. It was concluded that myofascial pain patients differed from those with disc displacement, joint disorders and no TMD in relation to some psychopathological symptoms, while the last three groups presented very similar profiles.
TL;DR: The results indicate that the most influential factor on shade taking was the light quality (P <0.0001); better results were obtained overall for the ideal light situation, and thicker samples gave better results.
Abstract: The purpose of this study was to elucidate some of the factors on which accurate shade taking depends. Custom shade tabs (0.5, 1.0 and 1.5 mm porcelain thickness) were fabricated from selected Vita and Shofu porcelains. Four main factors were investigated, namely, the difference between the two types of porcelain used, the effect of light quality, the effect of porcelain thickness and the experience of the observer. The chi-square test for independence at a probability level of P <0.05 was used to analyse the results. The results indicated that in ideal light there was no difference between the two porcelains (P=0.58). The experienced observers proved better than the novice observers in ideal light conditions (P=0.003). Thickness was also significant in the overall results (P=0.0001), in that thicker samples gave more accurate results. The results indicate that in adverse light, there was an overall difference between the two porcelains (P=0.046), but no difference between the experienced and novice observers. The thickness made no difference to the experienced or the novice observer in adverse light. These results indicate that the most influential factor on shade taking was the light quality (P <0.0001); better results were obtained overall for the ideal light situation. In ideal light thicker samples gave better results (P=0.0001).
TL;DR: The systems evaluated showed satisfactory retention force values, before and after fatigue testing, and a 5-year simulation of insertion and removal did not decrease retention values or fracture components.
Abstract: This study evaluated retention force and fatigue resistance of two overdenture attachment systems Twenty samples (O-ring and Bar-Clip) from two manufacturers (Conexao Sistemas de Protese and Lifecore Biomedical) were prepared and divided into four groups: (i) Conexao/O-ring; (ii) Conexao/Bar-Clip; (iii) Lifecore/O-ring and (iv) Lifecore/Bar-Clip, with five samples in each group They were submitted to mechanical fatigue test using a servohydraulic machine performing 5500 cycles of insertion and removal (f=08 Hz), immersed in artificial saliva Retention force values were obtained three times (0, 3000 and after 5500 cycles) simulating the clinical service, using a tensile strength at 1 mm min(-1) and load cell of 1 kN Data were analysed with analysis of variance and Tukey's test at 5% level Results showed that Conexao/Bar-Clip specimens had significantly higher retention values than Lifecore/Bar-Clip (4461 and 1844 N, respectively), Conexao/O-ring specimens had significantly lower values than Lifecore/O-ring (1391 and 1975 N, respectively) Conexao/Bar-Clip values were always significantly higher than those of Conexao/O-ring group (4461 and 1391 N, respectively) Lifecore (O-ring and Bar-Clip) presented similar values (1975 and 1844 N, respectively) The systems evaluated showed satisfactory retention force values, before and after fatigue testing Conexao/Bar-Clip specimens presented the highest values A 5-year simulation of insertion and removal did not decrease retention values or fracture components
TL;DR: There is a strong argument that chewing side preference is centrally controlled and provides food for thought regarding its significance in prosthodontics.
Abstract: Chewing side preference is a factor that could effect prosthodontic treatment. The purpose of this study was to determine whether chewing side was another type of hemispheric lateralization comparable with footedness, handedness, eyedness and earedness. Chewing side preference was tested in 189 subjects of whom 84 were partially edentulous, 98 had a full compliment of dental units (81 included implant-supported restoration restoring the missing teeth and 17 with fully intact dentitions), and seven were fully edentulous, restored with complete dentures. Laterality tests were carried out for the first cycle of mastication, handedness, footedness, earedness and eyedness and patient questionnaire. Most patients preferred chewing on the right side (78b3%) and were right sided. Chewing side preference correlated with other tested hemispherical lateralities. Missing teeth, occlusion type, lateral guidance, gender, implant-supported restorations and complete dentures do not affect the side preference for chewing. This presents a strong argument that chewing side preference is centrally controlled and provides food for thought regarding its significance in prosthodontics.
TL;DR: In this paper, the average maximum mouth opening and range of mouth opening in a representative sample of the Irish adult population was estimated and compared in patients with and without signs or symptoms of temporomandibular joint (TMJ) dysfunction syndrome and investigated the association between mouth opening with stature among populations.
Abstract: The aims of this study were to estimate the average maximum mouth opening and range of mouth opening in a representative sample of the Irish adult population, to compare mouth opening in patients with and without signs or symptoms of temporomandibular joint (TMJ) dysfunction syndrome and to investigate the association between mouth opening and stature among populations. As part of the Irish National Survey of Adult Oral Health, maximum mouth opening was measured and questionnaire data collected for 1513 adults, aged 16-99 years. The average maximum mouth opening was 43 mm for males and 41 mm for females. Mouth opening was found to reduce with age, independent of gender. No link was found between reduced mouth opening and TMJ dysfunction or between mouth opening and stature in populations.
TL;DR: Fluoride applied to enamel either in acidic solutions or as a pre-treatment, reduces enamel erosion; however, the actual clinical benefit appears low and more studies are required.
Abstract: Fluoride is known to reduce enamel solubility during the caries process. The aim of this investigation was to determine whether fluoride preparations affect erosion attributed to citric acid and citric acid-based soft drinks. Flat enamel specimens embedded in epoxy resin were prepared from caries free, human third molar teeth extracted from patients aged 18-35 years. Specimens were polished to have a profile within a tolerance of +/-0.3 microm measured on a profilometer. Specimens were taped to leave a 2 mm window of exposed enamel. Groups of specimens were exposed to citric acid and soft drinks with and without the addition of sodium fluoride or exposed to the same solutions after pre-treatment with fluoride products. Enamel loss was measured by profilometer after 10, 20 and 30 min of acid exposure. The different acidic solutions varied significantly in the amount of erosion produced both with and without the addition of fluoride. In addition, the different fluoride products differed significantly in the protective effect afforded. Both fluoride application methods reduced in mean terms, enamel erosion at all time points and by all acidic solutions. The majority of differences were <25% and as the study was powered to show differences as significant at or above this level few reached statistical significance. Fluoride applied to enamel either in acidic solutions or as a pre-treatment, reduces enamel erosion; however, the actual clinical benefit appears low. More studies are required, including investigations in situ.
TL;DR: Two-dimensional finite element analysis was applied to model the experimental stepped screw implant in a standard cross-section of the posterior human mandible digitized from a CT-generated patient data set and implies that v-thread (V) or large square-thread(S2) are optimal thread form for the experimental step screw implant.
Abstract: summary The purpose of this study was to determine the optimal thread form configuration for an experimental stepped screw implant. Two-dimensional finite element analysis was applied to model the experimental stepped screw implant in a standard cross-section of the posterior human mandible digitized from a CT-generated patient data set. Four different thread form configurations: v-thread (V), thin-thread (T), and two square-thread forms of 0·24 mm (S1) and 0·36 mm (S2) thread width were compared under oblique load in normal cortical bone condition. The support-type constraint position changed from middle to the base of the bone segment. In middle support-type constraint position only the thin-thread (T) model demonstrated significantly different stress distribution from the other three models, however, in base support-type constraint position T and S1 models demonstrated significantly different stress distribution from the other two models. The results implies that v-thread (V) or large square-thread (S2) are optimal thread form for the experimental stepped screw implant. While, minimal support constraints allow clearer differentiation of the stress picture between the different stepped screw types at the trabecular bone–implant interface.
TL;DR: The level of edentulousness was found to be high, more so in rural than in urban people and moreso in advancing age, with no significant difference between male and females.
Abstract: India has a large geriatric population (60+ years) of 77 millions, comprising 7.7% of its total population. One of the major handicaps in the elderly is loss of teeth, affecting their mastication, dietary intake and nutritional status. The present study was planned to assess the level of edentulousness, denture wearing and denture needs of the elderly in the community and to study the correlation between oral health parameters and socio-demographic variables, diet and body mass index (BMI). A total of 1240 (716 urban and 524 rural) elderly people were studied. It was found that 60% were dissatisfied with their function of mastication because of loss of teeth and lack of dentures. The level of edentulousness was found to be high, more so in rural than in urban people and more so in advancing age, with no significant difference between male and females. The striking finding of this study was the very low level of denture wearing. Only <50% of those needing complete dentures and <13% of those needing partial dentures were wearing dentures. The denture needs of the rural elderly were higher than those of the urban elderly. Vegetarians had a higher level of edentulousness compared with non-vegetarians. The BMI was not correlated with level of edentulousness.
TL;DR: The chi-squared test revealed that the ratio of females was significantly higher among students with TMD than without TMD, and multiple logistic regression models adjusted for age and gender demonstrated that chewing on one side caused an increased risk of TMJ noise, TMJ pain, and impaired mouth opening.
Abstract: We examined whether oral parafunctions are associated with symptoms of temporomandibular disorders (TMD) in 3557 Japanese university students, aged between 18 and 26 years. Participants completed a questionnaire regarding various oral parafunctions and subjective symptoms related to TMD, and underwent a dental examination. The prevalence of temporomandibular joint (TMJ) noise, TMJ pain and impaired mouth opening was 41.7, 16.0 and 16.3%, respectively. The most prevalent parafunction was sleeping on one side (60.2%), followed by supporting the jaw by leaning on the palm of the hand (44.8%). Mean age, decayed, missing and filled teeth, and number of teeth were not significantly different between TMD positive and negative groups according to unpaired t-test. The chi-squared test revealed that the ratio of females was significantly higher among students with TMD than without TMD. Multiple logistic regression models adjusted for age and gender demonstrated that chewing on one side caused an increased risk of TMJ noise [odds ratio (OR) = 1.52, P < 0.001], TMJ pain (OR = 1.54, P < 0.001), and impaired mouth opening (OR = 2.00, P < 0.001). Tooth clenching also increased the risk of TMJ noise (OR = 1.86, P < 0.001), TMJ pain (OR = 1.79, P = 0.001) and impaired mouth opening (OR = 1.88, P < 0.001). Further prospective cohort studies, including other potential risk factors, are required to clarify these relationships.
TL;DR: It is demonstrated that although at the end of 3-month evaluation period all desensitizers showed lower VAS sensitivity values compared with baseline, there were differences in the level of reduction of cervical dentine sensitivity.
Abstract: The aim of this study was to compare the long-term effectiveness of five desensitizing products on 25 male and 27 female patients (total 52) aged 21-67 years (mean 36 +/- 7 years) suffering from cervical dentine sensitivity. All subjects were seen by the same examiner (ID) who was blinded to the applied treatment for 3-month clinical study. Patients were asked to record their overall sensitivity by marking a point on a 10 cm Visual Analogue Scale (VAS). Two hundred and seventy-seven sensitive teeth were treated by one of the five desensitizing products, all of which were placed following manufacturers' instructions by the other investigator (AS). A paired (split mouth) study design was used and selection of quadrants was randomized. At the post-treatment and at 10 days and 3 months periods, sensitivity measurements were recorded by the same investigator (ID). Statistical analysis showed that all of the VAS scores at post-treatment evaluation points were significantly decreased compared with baseline data (P < 0.05). There was a significant reduction in mean sensitivity scores in the Protect Liner F and the Health-Dent Desensitizer groups when compared with Fluoline varnish at the 10-day time point (P < 0.05). At 3 months, the Protect Liner F group continued to show a significantly reduced sensitivity level when compared with Health-Dent Desensitizer, Single Bond, Fluoline and Gluma Desensitizer (P < 0.05). The present study demonstrated that although at the end of 3-month evaluation period all desensitizers showed lower VAS sensitivity values compared with baseline, there were differences in the level of reduction of cervical dentine sensitivity.
TL;DR: Results showed no difference between OA and control group in symptom-based outcomes for treatment or incidence of symptoms for prevention, and OA cannot be recommended for the management or prevention of TMD.
Abstract: To assess the effectiveness of occlusal adjustment (OA) for treating temporomandibular disorders (TMD) in adults and preventing TMD. The Cochrane Controlled Trials Register, MEDLINE and EMBASE were comprehensively searched using the Cochrane methods. Reports and review articles were retrieved. Unpublished reports or abstracts were considered from the SIGLE database. All randomized or quasi-randomized controlled trials comparing OA with placebo, reassurance or no treatment in adults with TMD. The outcomes were global measures of symptoms, pain, headache and limitation of movement. Data collection and analysis followed the Cochrane Oral Health Group's statistical guidelines. Results showed no difference between OA and control group in symptom-based outcomes for treatment or incidence of symptoms for prevention. There is no evidence that OA treats or prevents TMD. OA cannot be recommended for the management or prevention of TMD. Future trials should use standardized diagnostic criteria and outcome measures when evaluating TMD.
TL;DR: The layer-technique using GIC as dentine replacement and resin-based composite as enamel replacement results, according to previous biocompatibility testing, and clinical data, in optimal pulp protection and correct anatomic form over a 10-year period.
Abstract: The summarized scanning electron microscopic-supported micromorphologic data of a 10-year longitudinal clinical study of GIC/Hybrid composite posterior restorations is reported. The aim of this study was to compare the results to USPHS-compatible clinical criteria of the CPM index and to analyse the deterioration pattern and the success rate. Out of a total of 194 Class I and Class II fillings 46 restorations were at baseline, after 1, 3, 5, 7 and 10 years. The restorations were micromorphologically examined using gold-sputtered replicas and coded according to the M-criteria of the CPM index. The features for surface roughness, surface texture, marginal integrity, excess of material, marginal fracture, loss of material, marginal leakage and other filling imperfections were assessed. Eighteen fillings showed perfect margins, rapidly deteriorating after the first year of service. Despite poor micromorphologic marginal conditions all restorations retained optimal functional characteristics. Parallel longitudinal micromorphologic and clinical assessment of posterior GIC/Composite restorations revealed fine structure and deterioration patterns of the tooth-biomaterial interface. The layer-technique using GIC as dentine replacement and resin-based composite as enamel replacement results, according to previous biocompatibility testing, and clinical data, in optimal pulp protection and correct anatomic form over a 10-year period. The myth of the need for perfect marginal integrity requires further discussion.
TL;DR: A relationship between tinnitus and TMD was established in both examinations and patients seem to suffer especially from myofascial and TMJ pain.
Abstract: The literature has documented a controversial discussion on the possible relationship of otogenous symptoms and craniomandibular dysfunction since the 1920s. Therefore, an investigation was conducted which consisted of two parts: a case study with population-based controls and a cross-sectional study. The aim of the first study was to screen a group of patients suffering from acute or chronic tinnitus for temporomandibular disorders (TMD) in comparison with a population-based group of volunteers without tinnitus. To this end, 30 patients (13 females and 17 males, age 18-71 years) suffering from acute hearing loss associated with tinnitus, isolated acute tinnitus, and chronically transient tinnitus were examined for symptoms of craniomandibular dysfunction. The results were compared with those of clinical functional analysis from 1907 subjects selected representatively and according to age distribution from the epidemiological 'Study of Health in Pomerania' (SHIP); the occurrence of tinnitus was ruled out in these control subjects. Statistical analysis was performed with Chi-square and Mann-Whitney U-tests. Sixty per cent of the tinnitus patients and 36.5% of the control subjects exhibited more than two symptoms of TMD (P = 0.004). Tinnitus patients had significantly more muscle palpation pain (P < 0.001), temporomandibular joint (TMJ) palpation pain (P < 0.001), and pain upon mouth opening (P < 0.001) than the general population group. No statistical differences were found in TMJ sounds, limitation of mandibular movement, or hypermobility of the TMJ. Furthermore, 4228 subjects of the population group examined in the epidemiological study were screened for co-factors of tinnitus with the help of a multivariate logistic regression model which was adjusted for gender, age, and a variety of anamnestic and examined data. Increased odds ratios (OR) were found for tenderness of the masticatory muscles (OR = 1.6 for one to three painful muscles and OR = 2.53 for four or more painful muscles), TMJ tenderness to dorsal cranial compression (OR = 2.99), listlessness (OR = 2.0) and frequent headache (OR = 1.84) A relationship between tinnitus and TMD was established in both examinations. Tinnitus patients seem to suffer especially from myofascial and TMJ pain. A screening for TMD should be included in the diagnostic survey for tinnitus patients.
TL;DR: It was concluded that, when the environmental conditions were kept constant, the Adobe Photoshop 4.0 colour analysis program could be used to analyse the colour of images and the accuracy of shade tabs widely being used in colour matching should be readdressed.
Abstract: summary There appears to be a need for a reliable method for quantification of tooth colour and analysis of shade. Therefore, the primary objective of this study was to show the applicability of graphic software in colour analysis and secondly to investigate the reliability of commercial shade guides produced by the same manufacturer, using this digital technique. After confirming the reliability and reproducibility of the digital method by using self-assessed coloured images, three shade guides of the same manufacturer were photographed in daylight and in studio environments with a digital camera and saved in tagged image file format (TIFF) format. Colour analysis of each photograph was performed using the Adobe Photoshop 4·0 graphic program. Luminosity, and red, green, blue (L and RGB) values of each shade tab of each shade guide were measured and the data were subjected to statistical analysis using the repeated measure Anova test. The L and RGB values of the images taken in daylight differed significantly from those of the images taken in studio environment (P < 0·05). In both environments, the luminosity and red values of the shade tabs were significantly different from each other (P < 0·05). It was concluded that, when the environmental conditions were kept constant, the Adobe Photoshop 4·0 colour analysis program could be used to analyse the colour of images. On the other hand, the results revealed that the accuracy of shade tabs widely being used in colour matching should be readdressed.
TL;DR: The results suggest that the amount of leached monomers and VHN were influenced by forming polymer structure in activation and initiation stages of polymerization process with different light source energies and curing times.
Abstract: summary The purpose of this study was to evaluate the effect of the various light curing units (plasma arc, halogen and light-emitting diodes) and irradiation methods (one-step, two-step and pulse) using different light energy densities on the leachability of unreacted monomers (Bis-GMA and UDMA) and the surface hardness of a composite resin (Z250, 3M). Leachability of the specimens immersed for 7 days in ethanol was analysed by HPLC. Vicker's hardness number (VHN) was measured immediately after curing (IC) and after immersion in ethanol for 7 days. Various irradiation methods with three curing units resulted in differences in the amount of leached monomers and VHN of IC when light energy density was lower than 17·0 J cm−2 (P = 0·05). However, regardless of curing units and irradiation methods, these results were not different when the time or light energy density increased. When similar light energy density was irradiated (15·6–17·7 J cm−2), the efficiency of irradiation methods was different by the following order: one-step ≥ two-step > pulse. These results suggest that the amount of leached monomers and VHN were influenced by forming polymer structure in activation and initiation stages of polymerization process with different light source energies and curing times.
TL;DR: Evaluated adhesive systems found that thermal cycling significantly reduced the bond strengths of all adhesive systems, and failures after testing and prior to thermal cycle were most commonly adhesive failures between bonding resin and dentine associated with partial cohesive failures in the adhesive resin.
Abstract: The aim of this study was to evaluate the effect of thermal cycling on shear bond strength to bovine dentine of four current adhesive systems. Forty bovine incisors were ground flat with #600-grit silicon carbide paper to obtain superficial coronal dentine surfaces. Three one-bottle (etch and rinse) adhesive systems (Single Bond, Bond 1, One Step), and one self-etching primer adhesive system (Clearfil Liner Bond 2V) were evaluated. Dentine was conditioned and bonded with the adhesive systems tested according to the manufacturers' instructions. A cylindrical teflon mould (3 x 4 mm) was placed over the bonded area (to eliminate the bonded surface) and filled with composite resin. For each adhesive system the filling composite used was from the same manufacturer. Ten specimens were prepared for each material and all specimens were conditioned at 37 degrees C for 24 h. Five specimens of each material (half of the specimens) were thermocycled at 5000 cycles (at 5, 37, 55 and 37 degrees C) with a dwell time of 15 s and bonds were stressed in shear at a rate of 0.5 mm min(-1) until failure. Data were analysed by one-way anova and Student-Newman-Keuls rank test (alpha=0.05). Statistical analysis revealed that thermal cycling significantly (P 0.05), except for One Step which revealed the lowest bond strength, and varied from 22.5 +/- 3.34 to 10.98 +/-0.87 MPa. After thermal cycling, the bond strengths ranged from 9.35 +/- 1.13 to 6.06 +/- 1.77 MPa. Failures after testing and prior to thermal cycle were most commonly adhesive failures between the bonding resin and dentine associated with partial cohesive failures in the adhesive resin (type 2). Adhesive failures between bonding resin and dentin (type 1) after thermocycling were most commonly seen.
TL;DR: The present findings suggest that the myogenous TMDs without DID could be a distinct sub-group that can be a part of broader regional or generalized diseased entity.
Abstract: Summary The present study tested the hypothesis that the resting electromyographic (EMG) activities of sternocleidomastoid and trapezius muscles of myogenous temporomandibular disorder (TMD) patients would be significantly greater than healthy individuals. Eight masticatory muscle pain patients without disc interference disorders (DID) and 30 patients with DID along with 41 matched control subjects were included in the study. The resting EMG activities of sternocleidomastoid and trapezius muscles were recorded with a portable EMG machine. Pain intensities described over the muscles were recorded with a 100 mm visual analogue scale. The two groups of patients had significantly higher resting activities compared with control subjects. Patients (in both groups) who had pain in sternocleidomastoid and trapezius muscles reported significantly higher resting activities in the respective muscles than patients who were free of pain and the controls. The presence of pain over the examined muscles showed significant association with the myogenous TMDs without DID. The observed association of the cervical muscles with myogenous TMDs is expected to be a result of functional link between masticatory and cervical muscles. The present findings suggest that the myogenous TMDs without DID could be a distinct sub-group that can be a part of broader regional or generalized diseased entity.
TL;DR: In this paper, the most frequently suggested contributing factors to craniomandibular pain, viz., oral parafunctions and psychological stress, were studied in more detail during a 13-week study period, questionnaires were completed, in which among others, jaw muscle pain, bruxism behaviour, and experienced/anticipated stress were noted.
Abstract: summary In a single case study, the most frequently suggested contributing factors to craniomandibular pain, viz., oral parafunctions and psychological stress, were studied in more detail. During a 13-week study period, questionnaires were completed, in which, among others, jaw muscle pain, bruxism behaviour, and experienced/anticipated stress were noted. During about 40% of the nights, nocturnal masticatory muscle activity (NMMA) was recorded, using single-channel electromyography (EMG). The number of NMMA events per recorded hour was scored, using a detection threshold of 10% of the maximum voluntary contraction level. This threshold was established in a separate study, in which EMG was compared with polysomnography. Stepwise regression analyses indicated, that morning jaw muscle pain could be explained by evening jaw muscle pain for 64% and by alcohol intake for another 2%. In turn, evening jaw muscle pain was explained by daytime clenching for 56% and by vacuum sucking of the tongue for an additional 6%. Finally, daytime clenching was significantly explained by experienced stress for 30%. Data of the recorded nights showed, that variations in NMMA did not contribute to variations in morning jaw muscle pain. This case study corroborates the paradigm that experienced stress may be related to daytime clenching and, in turn, to evening and morning jaw muscle pain.
TL;DR: The data suggest that the application of occlusal load may not necessarily play a significant role in the progression of cervical tooth wear commonly referred to as abfraction.
Abstract: Toothbrush abrasion has been considered to cause cervical lesions. However, some investigators have proposed that occlusal loading factors direct tensile stresses at the cervical area, resulting in wedge-shaped abfraction defects. The purpose of this study is to investigate the role of axial and non-axial load on the development of cervical lesions. Matched paired premolars, extracted for orthodontic purposes, were used in a custom-fabricated toothbrushing apparatus. A periodontal sulcus width of 0b1 mm with 1 mm gingival recession was simulated with denture base resin. In phase 1, eight matched premolar pairs were subjected to 80 h (1b4 million strokes) of brushing and 300 g of toothbrush force. Toothpaste slurry was applied continuously through the toothbrush. One specimen in each pair was subjected to 250 h and 45 kg of continuous axial load, while the other unloaded tooth served as a negative control. In phase 2, 10 matched premolar pairs were subjected to the same conditions; however, the experimental teeth were subjected to 250 h and 45 kg of intermittent non-axial load, directed at a 45 degrees angle to the buccal cusp. Rubber impressions were made of the cervical lesions, then trimmed, weighed, and compared to determine the amount of tooth material lost. When teeth were loaded axially, there was significantly less tooth material loss (P < 0b02); however, when teeth were loaded non-axially, there was no significant difference (P =0b80) when compared with controls. Optical and scanning electron microscopy did not reveal any significant differences in the morphology between pairs. Our data suggest that the application of occlusal load may not necessarily play a significant role in the progression of cervical tooth wear commonly referred to as abfraction.