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1.
OBJECTIVES: To investigate the prevalence of alveolar bone loss around the first permanent molars, and first and second deciduous molars in Australian school-aged children attending the Royal Dental Hospital of Melbourne. METHOD: Nine hundred and ninety-five records were examined for useable bitewing radiographs. From these, radiographs of 542 Australian school children aged 5-12 years were used. The cervical-enamel junction (CEJ) to the alveolar bone crest (ABC) distance was measured using the transparent ruler on the magnifier. Each inter-dental site that was readable was scored as one for the following categories: not available (NA); no bone loss (NBL)- the CEJ-ABC was < or =2 mm; questionable bone loss (QBL): the distance from the CEJ-ABC was >2 and <3 mm; and definite bone loss (DBL): the distance from the CEJ to ABC was > or =3 mm. RESULTS: Seventy-one children (13.0%) were found to have 83 DBL sites, as determined by bone levels >3.0 mm from the CEJ. Seventy children had QBL lesions only, 50 children had DBL only and 21 children had both. The overall prevalence of bone loss was 26%. Second deciduous molars were found to be the most affected teeth with almost 75% lesions being distal. These teeth comprised 50% of the DBL lesions. Children of Asian-Far Eastern origin had a higher percentage of sites with bone loss compared with children of Caucasian origin, being 29.5% and 19.7%, respectively, but lower than that of children of Middle-Eastern origin (35.2%). When the data were analysed with relation to age, there was no relationship between age and prevalence of bone loss. CONCLUSION: In the population studied, there was an overall prevalence of periodontal bone loss of 26% and DBL of 13% in an Australian school-aged group. Calculus was detected infrequently and, where present, was associated with bone loss.  相似文献   

2.

Objective

The aim of this study was to evaluate the relationship between the number of pillar implants of implant-supported fixed prostheses and the prevalence of periimplant disease.

Material and Methods

Clinical and radiographic data were obtained for the evaluation. The sample consisted of 32 patients with implant-supported fixed prostheses in function for at least one year. A total of 161 implants were evaluated. Two groups were formed according to the number of implants: G1) ≤5 implants and G2) >5 implants. Data collection included modified plaque index (MPi), bleeding on probing (BOP), probing depth (PD), width of keratinized mucosa (KM) and radiographic bone loss (BL). Clinical and radiographic data were grouped for each implant in order to conduct the diagnosis of mucositis or peri-implantitis.

Results

Clinical parameters were compared between groups using Student''s t test for numeric variables (KM, PD and BL) and Mann-Whitney test for categorical variables (MPi and BOP). KM and BL showed statistically significant differences between both groups (p<0.001). Implants from G1 – 19 (20.43%) – compared with G2 – 26 (38.24%) – showed statistically significant differences regarding the prevalence of peri-implantitis (p=0.0210).

Conclusion

It seems that more than 5 implants in total fixed rehabilitations increase bone loss and consequently the prevalence of implants with periimplantitis. Notwithstanding, the number of implants does not have any influence on the prevalence of mucositis.  相似文献   

3.

Background

Trisomy 21 (T21) is a genetic disorder stemming from a chromosomal abnormality and characterized by general and mental retardation. Depending on the population, T21 is known to affect 1 in every 600–2000 live births. The current literature provides a mixed view on the oral health status of T21 individuals.

Aim

To establish the prevalence of dental caries, malocclusion, and trauma amongst children with T21 compared with non-T21 children in Riyadh, Saudi Arabia.

Methods

This cross-sectional study recruited non-T21 and T21 children between the ages of 7–15 years who were studying at the Saut Society. After informed consent was obtained from parents and both groups were matched by age and gender, trained examiners screened children at the dental clinic of King Saud University to record the presence of dental caries, malocclusion, and trauma in both groups.

Results

While there was no statistical difference between the two groups with regard to the mean decayed, missing, and filled teeth (DMFT) index (2.66 for T21 versus 3.11 for controls), T21 children had a higher prevalence of incisal fractures compared to the control group (24.73% versus 4.95%, respectively) and that was statistically significant (P < 0.05). There were also highly significant group differences concerning the prevalence of malocclusion. Therein, 45% of T21 children had a Class III incisor relationship compared with 8% of control children, and 50% of T21 children had a Class III molar relationship compared with 8% of control children.

Conclusions

While there was no significant difference in the incidence of caries between children with and without T21, practitioners should be aware of the disparities in malocclusion and trauma in this vulnerable population.  相似文献   

4.

Background

This cross-sectional retrospective study was conducted to determine association between breastfeeding duration, non-nutritive sucking habits, dental arch transverse diameters, posterior crossbite and anterior open bite in deciduous dentition.

Methods

415 children (228 males and 187 females), 4 to 6 years old, from a mixed Indian population were clinically examined. Based on written questionnaire answered by parents, children were divided into two groups: group 1 (breastfed for <6 months (n = 158)) and group 2 (breastfed for ≥6 months (n = 257)). The associations were analysed using chi-square test (P < 0.05 taken as statistically significant). Odds ratio (OR) was calculated to determine the strength of associations tested. Multivariate logistic regression analysis was done for obtaining independent predictors of posterior crossbite and maxillary and mandibular IMD (Inter-molar distance) and ICD (Inter-canine distance).

Results

Non-nutritive sucking (NNS) was present in 15.18% children (20.3% in group 1 as compared to 12.1% in group 2 (P = 0.024)). The average ICD and IMD in maxilla and average IMD in mandible were significantly higher among group 2 as compared to group 1 (P < 0.01). In mandible, average ICD did not differ significantly between the two groups (P = 0.342). The distribution of anterior open bite did not differ significantly between the two groups (P = 0.865). The distribution of posterior crossbite was significantly different between the two groups (P = 0.001). OR assessment (OR = 1.852) revealed that group 1 had almost twofold higher prevalence of NNS habits than group 2. Multivariate logistic regression analysis revealed that the first group had independently fourfold increased risk of developing crossbite compared to the second group (OR = 4.3). Multivariate linear regression analysis also revealed that age and breastfeeding duration were the most significant determinants of ICD and IMD.

Conclusions

An increased prevalence of NNS in the first group suggests that NNS is a dominant variable in the association between breastfeeding duration and reduced intra-arch transverse diameters which leads to increased prevalence of posterior crossbites as seen in our study. Mandibular inter-canine width is however unaffected due to a lowered tongue posture seen in these children.  相似文献   

5.

Objective:

The aims of this study were to compare the prevalence of temporomandibular disorders (TMD) in individuals submitted to either orthodontic or ortho-surgical Class III malocclusion treatment and to assess the influence of occlusal aspects on TMD severity.

Material and methods:

The sample consisted of 50 individuals divided into two groups, according to the type of treatment (orthodontic or orthodontic with orthognathic surgery). The presence of signs and symptoms of TMD was evaluated by an anamnestic questionnaire and a clinical examination, including TMJ and muscle palpation, active mandibular range of motion, joint noises and occlusal examination.

Results:

Based on the anamnestic questionnaire, 48% had no TMD, 42% had mild TMD and 10% had moderate TMD. The presence and severity of TMD did not show any relationship with the type of orthodontic treatment (p>0.05). The chi-square test showed a positive association (p<0.05) between TMD and non-working side occlusal interferences.

Conclusion:

Based on the methodology used and the results obtained, it may be concluded that Class III orthodontic treatment was not associated with the presence of TMD signs and symptoms and the non-working side contacts can be occlusal factors of risk. There was no significant difference in TMD prevalence between the studied groups (orthodontically treated patients and patients treated with orthodontics followed by orthognathic surgery).  相似文献   

6.

Objective

The present study evaluated morphometrically bone loss percentages in experimental periodontitis in rats, comparing different locations (lingual mandible, palatal maxilla and buccal maxilla) and two evaluation methods (distance and area methods).

Material and Methods

Ligatures were placed around the maxillary right second molar and around the mandibular right first molar in 14 female Wistar rats. The contralateral molars served as intragroup controls. After 4 weeks, the rats were sacrificed and their mandible and maxilla were removed. The specimens were dissected and stained with methylene blue dye. Bone loss was evaluated by two different methods on the surfaces of the defleshed jaw. In the first method, the distance from the cementoenamel junction (CEJ) to the alveolar bone crest was measured in the roots of teeth associated with ligature. In the second method, the area of bone loss was determined using the alveolar tissue bone, CEJ and the proximal region of roots associated with the ligature as reference. The data were converted to bone loss percentages caused by ligature: (ligated – unligated) x 100/ligated.

Results

When comparing the distance and area methods, no statistically significant difference was observed (p>0.05). Both methodologies indicated that the maxilla presented greater bone loss than the mandible and it was more accentuated on the buccal side than on the palatal side (p<0.05).

Conclusion

The findings of this study show that both the area and the distance methods can be used to evaluate bone loss caused by ligature placement in rats, and suggest applying the morphometric methodology to the maxilla on the buccal side.  相似文献   

7.

Background

Trisomy 21 (T21) is a congenital disorder characterized by triplication of Chromosome 21 components. Patients with T21 have an increased risk of acquiring periodontal disease due to their inability to maintain good oral hygiene. Consequently, it is important to determine an approach for disease prevention in this population.

Aim

The purpose of the study was to assess the periodontal health, through the prevalence of gingivitis and plaque, among children with T21 living in Riyadh, Saudi Arabia.

Subjects and method

This study included 93 children with T21 and 99 age- and gender-matched children without T21 between the ages of 7 and 15 years. Parents were informed about the study and provided informed consent. Trained examiners using standardized tools assessed the prevalence rates of gingivitis and plaque in all children.

Results

Gingivitis prevalence was elevated among T21 children (46.9%) compared to controls (34%) in all arch sextants except the mandibular middle (P < 0.01). Comparing the two groups, the prevalence of plaque was higher in the maxillary right sextant of the T21 group and the mandibular middle sextant of the control group (P < 0.05).

Conclusion

T21 children have significantly elevated plaque levels, resulting in greater prevalence of gingivitis, compared to healthy children. Preventive measure, such as oral health awareness programs, should be delivered early to parents and continued at school to encourage and motivate children.  相似文献   

8.

Objectives:

The antiplaque and antigingivitis effect of Lippia Sidoides (LS) was evaluated in this in vivo investigation.

Material and Methods:

Twenty-three subjects participated in a cross-over, double-blind clinical study, using 21-day partial-mouth experimental model of gingivitis. A toothshield was constructed for each volunteer, avoiding the brushing of the 4 experimental posterior teeth in the lower left quadrant. The subjects were randomly assigned initially to use either the placebo gel (control group) or the test gel, containing 10% LS (test group).

Results:

The clinical results showed statistically significant differences for plaque index (PLI) (p<0.01) between days 0 and 21 in both groups, however only the control group showed statistically significant difference (p<0.01) for the bleeding (IB) and gingival (GI) index within the experimental period of 21 days. On day 21, the test group presented significantly better results than the control group with regard to the GI (p<0.05).

Conclusions:

The test gel containing 10% LS was effective in the control of gingivitis.  相似文献   

9.

The aim

The aim of this study was to investigate the effect of dexketoprofen trometamol, meloxicam, diclofenac sodium on any untreated alveolar bone when they are used as drugs for another indication.

Materials and Methods

Twenty eight male Spraque-Dawley rats were randomized into four groups as dexketoprofen trometamol (Group I), meloxicam (Group II), diclofenac sodium (Group III) and control group. Nonsteroidal anti-inflammatory drugs (NSAID) were administered after a fibula fracture for 10 days. Untreated alveolar bone was histopathologically examined for spongious bone density, osteoclastic density and osteoblastic density.

Results

Spongious bone density was lower in study groups (Group I, group II and group III) than the control group (p<0.05). In contrast, the increase in osteoclastic density was observed in other groups apart from the control group (p<0.05). Osteoblastic density was evaluated and it was determined that group II and group III had lower results than the control group (p<0.05) but group I was equal to the control group.

Conclusion

This study showed that systemically administrated NSAIDs have the potential to affect untreated alveolar bone. This should also be considered in long term use of NSAIDs.Key Words: Non-steroidal anti-inflammatory agents, bone remodeling, osteoblast, osteoclast, maxillary bone  相似文献   

10.

Objective:

This study investigated the influence of the last apical instrument of the ProTaper system with and without 2.5% sodium hypochlorite for cleaning mandibular central incisors.

Material and Methods:

Thirty two mandibular central incisors were divided into six study groups: Group I – F1 instrument with 2.5% sodium hypochlorite; Group II – F1 and F2 with 2.5% sodium hypochlorite; Group III – F1, F2 and F3 with 2.5% sodium hypochlorite; Group IV – F1 with distilled water; Group V – F1 and F2 with distilled water; Group VI – F1, F2 and F3 with distilled water. The two remaining teeth comprised the negative control group. The specimens were prepared following the principles of the technique suggested by the manufacturer and then submitted to histological preparation and morphometric analysis. Data were analyzed statistically by the Kruskal Wallis test at 1% significance level.

Results:

There was statistically significant difference (p<0.01) between all study groups, except between Groups I and VI.

Conclusions:

It was concluded that no technique allowed complete cleaning of the root canals. However, the technique of finishing preparation of the apical third with the F3 instrument with 2.5% sodium hypochlorite irrigation was the most effective.  相似文献   

11.

Objective

To assess microleakage in conservative class V cavities prepared with aluminum-oxide air abrasion or turbine and restored with self-etching or etch-and-rinse adhesive systems.

Material and Methods

Forty premolars were randomly assigned to 4 groups (I and II: air abrasion; III and IV: turbine) and class V cavities were prepared on the buccal surfaces. Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV -self-priming etchant (Tyrian-SPe). Cavities were restored with One Step Plus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50% silver nitrate, and serially sectioned. Microleakage at the occlusal and cervical interfaces was measured in mm and calculated by a software. Data were subjected to ANOVA and Tukey’s test (α=0.05).

Results

Forty premolars were randomly assigned to 4 groups (I and II: air abrasion; III and IV: turbine) and class V cavities were prepared on the buccal surfaces. Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV -self-priming etchant (Tyrian-SPe). Cavities were restored with One Step Plus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50% silver nitrate, and serially sectioned. Microleakage at the occlusal and cervical interfaces was measured in mm and calculated by a software. Data were subjected to ANOVA and Tukey’s test (α=0.05).

Conclusion

Marginal seal of cavities prepared with aluminum-oxide air abrasion was different from that of conventionally prepared cavities, and the etch-and-rinse system promoted higher marginal seal at both enamel and dentin margins.  相似文献   

12.
13.

Objective

To compare the incidence of postoperative pain after the use of calcium hydroxide powder mixed with normal saline or 0.2% chlorhexidine digluconate as intracanal medicament.

Participants

Fifty-five subjects aged 17–60 years with teeth diagnosed to have apical periodontitis.

Intervention

Two-visit conventional root canal treatment of seventy teeth. The teeth were divided by randomization (balloting) into two groups: control group and experimental group, each with thirty-five teeth treated with calcium hydroxide mixed with normal saline or with 0.2% chlorhexidine digluconate as intracanal medicament respectively. Incidence of postoperative pain was assessed using the universal pain assessment tool and whether or not analgesic was taken.

Main outcome measured

Incidence of post-operative pain.

Result

Postoperative pain occurred only at 1-day and 1-week reviews. In the control group, the overall incidence of pain was the same at both review periods (5.7%), while the experimental group showed a slight decrease in incidence between 1-day (17.2%) and 1-week (11.4%) reviews. Incidence of flare-ups was more in the experimental group (11.4%) than in the control group (5.7%). No significant statistical differences between the two groups were observed (p > 0.05).

Conclusion

The incidence of postoperative pain was lower in the normal saline treatment group, but the difference was not statistically significant.  相似文献   

14.

Objective:

The long face pattern is a facial deformity with increased anterior total facial height due to vertical excess of the lower facial third. Individuals with long face may present different degrees of severity in vertical excess, as well as malocclusions that are difficult to manage. The categorization of vertical excess is useful to determine the treatment prognosis. This survey assessed the distribution of ethnically different individuals with vertical excess according to three levels of severity and determined the prevalence of long face pattern.

Material and Methods:

The survey was comprised of 5,020 individuals of Brazilian ethnicity (2,480 females and 2,540 males) enrolled in middle schools in Bauru-SP, Brazil. The criterion for inclusion of individuals with vertically impaired facial relationships was based on lip incompetence, evaluated under natural light, in standing natural head position with the lips at rest. Once identified, the individuals were classified into three subtypes according to the severity: mild, moderate, and severe. Then the pooled sample was distributed according to ethnical background as White (Caucasoid), Black (African descent), Brown (mixed descent), Yellow (Asian descent) and Brazilian Indian (Brazilian native descent). The Chi-square (χ2) test was used (p<0.05) to compare the frequency ratios of individuals with vertically impaired facial relationships in the total sample and among different ethnicities, according to the three levels of severity.

Results:

The severe subtype was rare, except in Black individuals (7.32%), who also presented the highest relative frequency (45.53%) of moderate subtype, followed by Brown individuals (43.40%). In the mild subtype, Yellow (68.08%) and White individuals (62.21%) showed similar and higher relative frequency values.

Conclusions:

Black individuals had greater prevalence of long face pattern, followed by Brown, White and Yellow individuals. The prevalence of long face pattern was 14.06% in which 13.39% and 0.68% belonged to moderate and severe subtypes, respectively.  相似文献   

15.

PURPOSE

Translucency of all-ceramic restorations is an important factor which affects the final appearance and esthetic outcome of the restoration. The aim of this study was to evaluate the effect of the shade of coloring liquid on the translucency of zirconia framework.

MATERIALS AND METHODS

Thirty zirconium oxide core plate (15 × 12 × 0.5 mm) were divided into 6 groups of 5 plates each. Each group was classified according to the shade of coloring liquid based on Vita Classic Scale (A2, A3, B1, C2, and D2), and each sample was immersed in coloring liquid for 3 seconds as recommended by the manufacturer, except for the control group. Contrast ratio, as a translucency parameter, was calculated using a spectrophotometer and the data were analyzed with oneway analysis of variance (ANOVA) and Tukey''s honestly significant differences (HSD) tests (α=.05).

RESULTS

Significant differences in translucency among the control and test groups, and the B1 shaded group and other shades was observed. There were no significant differences among A2, A3, C2, and D2 shaded groups.

CONCLUSION

The translucency of the zirconium oxide cores was affected by the coloring procedure and significant differences in the translucency measurements were identified between specific shades.  相似文献   

16.

PURPOSE

The aim of this study was to evaluate the stability of arginine-glycine-aspartic acid (RGD) peptide coatings on implants by measuring the amount of peptide remaining after installation.

MATERIALS AND METHODS

Fluorescent isothiocyanate (FITC)-fixed RGD peptide was coated onto anodized titanium implants (width 4 mm, length 10 mm) using a physical adsorption method (P) or a chemical grafting method (C). Solid Rigid Polyurethane Foam (SRPF) was classified as either hard bone (H) or soft bone (S) according to its density. Two pieces of artificial bone were fixed in a customized jig, and coated implants were installed at the center of the boundary between two pieces of artificial bone. The test groups were classified as: P-H, P-S, C-H, or C-S. After each installation, implants were removed from the SRPF, and the residual amounts and rates of RGD peptide in implants were measured by fluorescence spectrometry. The Kruskal-Wallis test was used for the statistical analysis (α=0.05).

RESULTS

Peptide-coating was identified by fluorescence microscopy and XPS. Total coating amount was higher for physical adsorption than chemical grafting. The residual rate of peptide was significantly larger in the P-S group than in the other three groups (P<.05).

CONCLUSION

The result of this study suggests that coating doses depend on coating method. Residual amounts of RGD peptide were greater for the physical adsorption method than the chemical grafting method.  相似文献   

17.

Objective

This in vitro study evaluated the influence of two 10% carbamide peroxide bleaching agents - a commercial product (Opalescence PF; Ultradent Products, Inc.) and a bleaching agent prepared in a compounding pharmacy - on the chemical degradation of a light-activated composite resin by determining its release of ions before and after exposure to the agents.

Material and Methods

Thirty composite resin (Filtek Z250; 3M/ESPE) samples were divided into three groups: group I (exposed to Opalescence PF commercial bleaching agent), group II (exposed to a compounded bleaching agent) and group III (control - Milli-Q water). After 14 days of exposure, with a protocol of 8 h of daily exposure to the bleaching agents and 16 h of immersion in Milli-Q water, the analysis of ion release was carried out using a HP 8453 spectrophotometer. The values were analyzed statistically by ANOVA, Tukey''s test and the paired t-tests. The significance level was set at 5%.

Results

After 14 days of the experiment, statistically significant difference was found between group II and groups I and III, with greater ion release from the composite resin in group II.

Conclusions

The compounded bleaching agent had a more aggressive effect on the composite resin after 14 days of exposure than the commercial product and the control (no bleaching).  相似文献   

18.
19.

Aim

The objective of present study was to examine influence of adhesives and methods of enamel pretreatment on the shear bond strength (SBS) of orthodontic brackets. The adhesives used were resin-reinforced glass ionomer cements-GIC (Fuji Ortho LC) and composite resin (Transbond XT).

Material and Methods

The experimental sample consisted of 80 extracted human first premolars. The sample was divided into four equal groups, and the metal brackets were bonded with different enamel pretreatments by using two adhesives: group A-10% polyacrylic acid; Fuji Ortho LC, group B–37% phosphoric acid; Fuji Ortho LC, group C–self etching primer; Transbond XT, group D–37% phosphoric acid, primer; Transbond XT. SBS of brackets was measured. After debonding of brackets, the adhesive remnant index (ARI) was evaluated.

Results

After the statistical analysis of the collected data was performed (ANOVA; Sheffe post-hoc test), the results showed that significantly lower SBS of the group B was found in relation to the groups C (p=0.031) and D (p=0.026). The results of ARI were similar in all testing groups and it was not possible to determine any statistically significant difference of the ARI (Chi- square test) between all four experimental groups.

Conclusion

The conclusion is that the use of composite resins material with appropriate enamel pretreatment according to manufacturer’s recommendation is the “gold standard” for brackets bonding for fixed orthodontic appliances.Key words: orthodontic brackets, shear strength, adhesive, enamel preparation  相似文献   

20.

Aim

Recent studies claim that haemostatic agents can be used as bone graft substitutes. The aim of this study was to compare the efficacy of alloplastic bone graft with absorbable gelatin sponge in prevention of periodontal defects distal to mandibular second molar after the surgical removal of impacted mandibular third molars.

Materials and methods

A prospective, randomized, single-blind split-mouth study was designed. The study consisted of 25 patients requiring surgical removal of bilateral impacted mandibular 3rd molars. The surgical sites were randomly divided into 2 groups: group I: G-graft (hydroxyapatite + collagen, study group) and group II: Abgel (absorbable gelatin sponge, control group). Patients were recalled on lst and 7th postoperative days and 3rd and 6th postoperative months. Probing depth, alveolar bone levels and soft tissue wound healing were evaluated. Paired t test was used to compare pre and post-operative alveolar bone levels and probing depth (PD). Wilcoxon signed ranks test was used to compare the wound healing.

Results

The soft tissue wound healing, PD and the distance between the cemento–enamel junction on the distal aspect of mandibular second molar (point A) and the alveolar crest on the distal aspect of the same tooth (point B) were significantly higher in group I as compared to group II.

Conclusion

This study reveals an increase in the alveolar bone level, improvement of PD and better wound healing in group I. Group II subjects required longer healing time than the normal. The authors disagree the claim that the haemostatic agents can be used as bone graft substitutes. However, long-term, multicenter, randomized controlled clinical trials are required.  相似文献   

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