The effect of ferrule and core material on fracture resistance of endodontically treated anterior teeth restored with ceramic crowns after artificial aging.

OBJECTIVES: To assess the influence of ferrule and core type on the fracture strength of endodontically treated anterior teeth (ETAT) and identify the failure mode type and distribution across different core types and ferrule conditions. METHODS: Sixty extracted human central incisors were endodontically treated, decoronated and divided into two main groups (F=with ferrule, NF=no ferrule). Each main group was further subdivided into three subgroups according to the core material used: direct composite cores (DC), Ribbond fibre-reinforced composite cores (RIB-DC), and glass fibre post (GFP) with direct composite cores (GFP-DC). All specimens received E.max crowns and underwent thermal cycling and cyclic loading. Subsequently, the fracture resistance was tested with static loads applied to the crown restoration. Two-Way ANOVA and Chi square tests identified significant differences among the groups (p < 0.05). RESULTS: The means and standard deviations (SD) of fracture loads in Newtons (N) for specimens in the F subgroups were RIB-DC: 465.0 (104.20), GFP-DC: 367.6 (79.59), DC: 275.8 (68.48), and in NF subgroups were RIB-DC: 110.8 (24.33), GFP-DC: 95.6 (25.47), DC: 67.4 (7.46). Specimens with ferrule yielded significantly higher fracture loads than those without ferrule (p = 0.0054). In the F groups, fracture loads of specimens with RIB-DC cores were significantly higher than those with GFP-DC (p = 0.0019) and those with DC (p = 0.0001). Moreover, fracture loads for the GFP-DC were significantly higher than those for the DC (p = 0.0026). The GFP-DC specimens showed the highest incidence of catastrophic failures (p = 0.0420). CONCLUSIONS: Using fibre-reinforced composite (FRC) cores significantly increased fracture resistance in ETAT with ferrule. The failure modes repairable and possibly repairable were dominant in most specimens. CLINICAL SIGNIFICANCE: When restoring ETAT with insufficient coronal tooth structure, preserving 2 mm of tooth structure ferrule and preparing cores with FRC can increase fracture resistance and reduce the incidence of non-repairable catastrophic fractures of teeth.

Effects of silane coupling treatment on the clinical performance of direct repaired resin-based composite (RBC) restorations with or without prior surface sandblasting: A randomized controlled trial.

OBJECTIVE: To evaluate the effects, of using silane coupling agent within the procedures of repairing old composite restorations with or without sandblasting their surfaces, on the clinical performance of repaired composite restorations. METHODS: The study involved repairing 130 Class I and II defective composite restorations. After recurrent caries removal, the repair process included etching with 37 % phosphoric acid, Adper Single Bond 2 application for bonding and Filtek Z250 composite for restoring all defects. The restoration surfaces were subjected to one of the following additional surface treatments within the repair process: Control: No additional treatment; the Silane-Adhesive treatment: A separate step involved the application of a silane coupling agent after acid etching; and the Sandblast-Silane-Adhesive treatment: included intra-oral sandblasting of old composite surfaces followed by silane application. Two calibrated examiners evaluated all repaired restorations according to a modified USPHS criteria after 6 months. Comparisons of the clinical performance between the treatment groups were made using Chi-square test, while responses to cold tests before and after repair treatment were made using Wilcoxon's Signed Rank's (α = 0.05). RESULTS: Of 130 cases, only 116 cases turned up for evaluation. The primary reasons for composite repair were recurrent caries and anatomical deficiencies. No statistically significant differences were found between the groups for all clinical criteria (p > 0.05). The control group experienced one total and two partial retention losses. CONCLUSIONS: The application of a silane coupling agent, with or without intra-oral sandblasting, demonstrated no improvement on the clinical performance of repaired posterior composites after 6-months. CLINICAL SIGNIFICANCE: Surface treatment of defective composite restorations using silane with intra-oral sandblasting within their repair process offered marginal improvement in their clinical performance over conventional etching technique, but insignificantly so. Repair reduced exaggerated cold test responses and eliminated POS within 6-months. Repair reduces cold sensitivity and promotes restoration longevity. This clinical trial was registered at ClinicalTrials.gov with the registration number NCT06005571.

Postoperative sensitivity in posterior restorations restored with self-adhesive and conventional bulk-fill resin composites: A randomized clinical split-mouth trial.

OBJECTIVE: To compare the postoperative sensitivity (POS) of a self-adhesive bulk-fill resin composite with that of a conventional bulk-fill resin composite in posterior restorations. METHODS: Class I and II (n = 166) cavities of at least 3 mm depth, in 83 participants were restored by: (TEST: Surefil one™ Self-Adhesive bulk-fill (n = 83); and CONTROL: Filtek™ Bulk-Fill posterior composites (n = 83). The presence and intensity of POS associated with the restorations was evaluated at 24 h, 1 week and 1 month intervals using the Visual Analogue Scale (VAS). Comparisons of POS presence between the two treatment groups were made using the Chi-square and Fisher exact tests, while Mann-Whitney and Friedman tests were used to compare the intensity of POS (α=0.05). RESULTS: Forty-two of participants (25.3%; 95% CI 19.3 to 32.4) reported presence of POS after 24 h and none of the participants reported POS after 1 month. The presence of POS was not significantly affected by the restorative material after 24 h, 1 week and 1 month (p>0.05). After 1 week, the participants in the Surefil one™ group reported significantly less intensity of POS than the participants in the Filtek™ Bulk-Fill group (p = 0.02). CONCLUSIONS: The use of Surefil one™ self-adhesive resin composite did not significantly increase the presence of POS compared to the use of the conventional bulk-fill resin composite. However, the intensity of POS was significantly less in the Surefil one ™ group after one week. CLINICAL SIGNIFICANCE: The use of a self-adhesive bulk-fill resin composite in posterior restorations did not increase the presence of POS more than the use of a conventional bulk-fill resin composite. However, it decreased the intensity of POS after one week. This clinical trial was registered at ClinicalTrials.gov; the registration number is NCT05567263.

Endodontic decision making for asymptomatic root-filled teeth with apical periodontitis - A radiographic survey.

The aim of the study was to compare decision making for asymptomatic root-filled teeth among dentists with differing educational backgrounds. Case scenarios based on 14 radiographs were created and 150 participants were asked to choose from five alternative treatment decisions and to state the rationale. Demographic data of the participants were recorded. Frequency distribution and cross-tabulation were performed; chi square testing was used for comparisons and logistic regression was performed to detect significant differences. The overall response rate was 87.3%. The practitioners chose intervention predominantly with non-surgical retreatment a common choice. Poor technical quality was a driving factor, while the existing poor coronal restoration and the need for a crown were generally not taken into account by general dentists. Speciality and experience were significant factors. Practitioners were more inclined to retain rather than extract teeth. It is concluded that clear guidelines listing factors to consider for intervention are required.

The influence of different factors on the oral health status of smoking and nonsmoking adults.

AIM: The aim of this study to determine the influence of smoking on self-reported oral health status among university students. MATERIALS AND METHODS: Voluntary sample of 669 adults of 18 to 26 years old were invited to participate in the study. They were asked to read a self-designated questionnaire and a covering letter which explained the purpose of the study. The questionnaire addressed self-reported demographics, oral hygiene and smoking habits; knowledge about smoking and its effects on oral health. Data were statistically analyzed using Chi-square test to determine statistically significant differences across the oral health status. RESULTS: The sample included 340 (56.7%) males and 240 (43.3%) females; 56.8% of the subjects were nonsmokers; 43.2% were current smokers, and 17.5% smoke argileh. Almost 24.7% of subjects started smoking because of emotional effects; 66.9% did not smoke because of its harm to health. The percentage of subjects with dental plaque on their teeth was 27.1%, and with calculus was 27.9%, and with stains was 26.9%. About 35.5% of the subjects brushed their teeth once daily. Statistically, significant association was proven between smoking and gender (p < 0.01); and smoking and halitosis (p < 0.01). CONCLUSION: Smoking is significantly related to esthetics, calculus, tooth stains, halitosis, gingival bleeding, and gender with p < 0.01, p < 0.01, p < 0.01, p < 0.01, p = 0.05, and p < 0.01 respectively.

Two-body wear of different ceramic materials opposed to zirconia ceramic.

STATEMENT OF PROBLEM: Little is known about the wear behavior of ceramics opposed to unveneered zirconia and whether wear varies according to microstructure, surface toughness, and flexural strength of the ceramics. PURPOSE: The purpose of this study was to evaluate the 2-body wear resistance of 5 ceramics opposing unveneered zirconia ceramic. MATERIAL AND METHODS: Yttrium-stabilized zirconia, lithium disilicate glass ceramic, leucite-reinforced glass ceramic, fluorapatite glass ceramic, and nanofluorapatite glass ceramic specimens (n=8) were tested against standardized zirconia balls. Wear tests were performed in a dual-axis mastication simulator. Wear resistance was calculated by measuring the vertical and volumetric substance loss using a laser scanner. Specimen surfaces were evaluated at x50 and x500 magnification using SEM. Data were statistically analyzed using 1-way ANOVA and Fisher's exact test (alpha=.05). RESULTS: Zirconia specimens demonstrated significantly lower vertical and volumetric loss than other ceramics (P<.05). The wear of fluorapatite and nanofluorapatite glass ceramics was significantly greater than that of leucite-reinforced and lithium disilicate glass ceramics (P<.05). SEM images showed no cracks or flaws in the zirconia and leucite-reinforced glass-ceramic specimens, indicating a mixture of attritional and adhesive wear. Other ceramic specimens exhibited cracks and chipped particle spaces which were consistent with fatigue wear. Zirconia demonstrated the lowest vertical and volumetric wear values. Leucite-reinforced and lithium disilicate glass ceramics demonstrated nonsignificant differences in volumetric wear, but these values were significantly lower than those observed for nanofluorapatite and fluorapatite glass ceramics (P<.05). CONCLUSIONS: Wear varied according to the structure of the ceramic tested. Wear was of the fatigue type, and was significantly lowest in the zirconia specimens tested.

Effects of endodontic post surface treatment, dentin conditioning, and artificial aging on the retention of glass fiber-reinforced composite resin posts.

STATEMENT OF PROBLEM: Several post surface treatments with or without the application of a bonding agent have been recommended to improve the bond strength of resin cements to posts. A regimen that produces the maximum bond strength of glass fiber-reinforced composite resin posts has not been verified. PURPOSE: The purpose of this study was to evaluate the influence of post surface conditioning methods and artificial aging on the retention and microleakage of adhesively luted glass fiber-reinforced composite resin posts. MATERIAL AND METHODS: Seventy-two endodontically treated single-rooted teeth were prepared for glass fiber-reinforced composite resin posts. The posts were submitted to 3 different surface treatments (n=24), including no treatment, etching with phosphoric acid, and airborne-particle abrasion. Subgroups of the posts (n=8) were then allocated for 3 different experimental conditions: no artificial aging, no bonding agent; no artificial aging, bonding agent; or artificial aging, bonding agent. The posts were luted with resin cement (Calibra). Post retention was measured in tension at a crosshead speed of 2 mm/min. The posts assigned for microleakage investigation were placed in fuchsin dye for 72 hours. The dislodged posts and the post spaces were examined microscopically to evaluate the mode of failure and explore the microleakage. Data were analyzed by 2-way ANOVA followed by Tukey HSD test (alpha=.05). RESULTS: The mean (SD) retention values for test groups ranged from 269 (63.8) to 349 (52.2) N. The retention values of the airborne-particle-abrasion group were significantly higher than those of the acidic-treatment and no-treatment groups. The application of bonding agent on the post surface produced no significant influence on retention. The mean retention values after artificial aging were significantly higher than without artificial aging. Microscopic evaluation demonstrated that the failure mode was primarily mixed. CONCLUSIONS: Treating the surface of the posts with phosphoric acid for 15 seconds before cementation produced no significant improvement in post retention. Airborne-particle abrasion of the surface of the post significantly improved post retention.

Clinical assessments and patient evaluations of the esthetic quality of maxillary anterior restorations.

PURPOSE: Dental esthetics has increasingly become an important and rewarding discipline in dentistry as patients have begun to request anterior restorations of high esthetic quality. Clinicians must be prepared to meet the esthetic demands and high expectations of their patients. Different variables may influence the esthetic quality of restorations. Quality evaluations may vary with clinical or patient assessments. This study attempted to assess the esthetic quality of maxillary anterior restorations in order to determine the percentage of restorations with satisfactory quality, examine variables affecting esthetic quality, and make comparisons between agreements and disagreements in clinical and patient evaluations. MATERIALS AND METHODS: Restorations in patients attending different dental clinics in Irbid, Jordan were examined. Clinicians compared the color and shape of the restorations with those of a natural tooth using Ryge criteria, and patients evaluated the same parameters and the surface texture using a Visual Analogue Scale (VAS). Evaluations ranked the quality as good, satisfactory, or poor. RESULTS: The percentage of esthetic complaints was 32.4%, whereas the percentage of satisfactory restorations revealed was 43.8% and 67.6% by clinical and patient assessments, respectively. Restorations yielded significantly better scores on both evaluations when they were prepared by dental students, made in the Dental Teaching Centre (DTC), or were less than one year old. The number of agreements between clinical and patient rankings was significantly less than disagreements. CONCLUSIONS: There were statistically significant disagreements on the esthetic quality between clinicians and patients. Age, gender, practice sector, qualification of the operator, type, and longevity of restoration significantly affected the assessments.

Effect of acid conditioning of root canal dentin on the retention of adhesively luted glass fiber-reinforced composite (FRC) posts.

PURPOSE: To assess the retention of glass FRC posts luted with resin cements after conditioning the canal dentin with different acidic treatments. METHODS: Post spaces were prepared in six groups of eight endodontically treated extracted teeth. Glass FRC posts were luted after etching the canal dentin with phosphoric acid and/or applying ED-Primer, Clearfil New Bond or XP Bond. The groups with their respective etching time, primer and cement combinations were as follows. ED: ED-Primer only and Panavia 21; ED15: 15 seconds phosphoric acid treatment, ED-Primer and Panavia 21; NB15: 15 seconds phosphoric acid treatment, Clearfil New Bond and Panavia 21; NB30: 30 seconds phosphoric acid treatment, Clearfil New Bond and Panavia 21; XP15: 15 seconds phosphoric acid treatment, XP Bond and Calibra; XP30: 30 seconds phosphoric acid treatment, XP Bond and Calibra. Specimens were stored in water for 30 days and subjected to simulated aging conditions. Post retention was measured in tension at a crosshead speed of 2 mm/minute. Analysis of variance and Bonferroni multiple range tests were conducted for data analysis. RESULTS: The mean (standard deviation) retention values in Newtons (N) were: ED: 180.9 (44.9); ED15: 278.3 (37.7); NB15: 283.8 (84.9); NB30: 187.7 (60.0), XP15: 216.8 (46.8), XP30: 199.6 (34.0). The retention values of ED15 and NB15 were significantly higher than those of ED and NB30 groups respectively. There were no statistically significant differences between XP Bond groups. Microscopic evaluation of post surfaces demonstrated that the debonding failure was adhesive at the cement-post and cement-dentin interfaces.

Wear resistance of nanofilled composite resin and feldspathic ceramic artificial teeth.

STATEMENT OF PROBLEM: The wear resistance of nanofilled composite resin and feldspathic ceramic artificial teeth may vary according to the material type and physical characteristics of the antagonist. PURPOSE: The purpose of this study was to evaluate the wear resistance of nanofilled composite resin and feldspathic ceramic artificial teeth after simulated mastication against steatite, zirconia, and alumina antagonists. MATERIAL AND METHODS: The study evaluated 6 groups of artificial teeth: 3 groups of 8 nanofilled composite resin teeth (Condyloform II NFC) and 3 groups of 8 feldspathic ceramic teeth (Bonartic CT). Three sets of 16 steatite, 16 zirconia, and 16 alumina cusp-shaped antagonist surfaces were fabricated and used to test wear resistance. Each group was loaded for 600,000 cycles. The wear resistance was analyzed by measuring vertical and volume substance lost (microm and mm(3), respectively), determined with a laser scanner. Data were statistically analyzed using 2-way ANOVA and Games-Howell test (alpha=.05). RESULTS: The influence of the materials tested and antagonists was statistically significant. The composite resin teeth showed significantly higher vertical and volume substance loss than ceramic teeth opposing steatite cusps (P<.001; P=.04, respectively), while composite resin teeth opposing alumina and zirconia cusps demonstrated less wear than ceramic teeth. However, the latter differences were not statistically significant. CONCLUSIONS: The wear behavior of nanofilled composite resin and feldspathic ceramic teeth varies according to the type of antagonistic material. However, alumina and zirconia ceramics caused less wear in antagonists than steatite ceramic.

Effect of dentin conditioning on retention of airborne-particle-abraded, adhesively luted glass fiber-reinforced resin posts.

STATEMENT OF PROBLEM: The smear layer covering root canal dentin as a result of post space preparation procedures may negatively affect the retention of adhesively cemented glass fiber-reinforced resin posts. PURPOSE: The purpose of this study was to evaluate the retention of airborne-particle-abraded glass fiber posts luted with 3 different bonding systems after conditioning the canal dentin with acidic conditioning methods. MATERIAL AND METHODS: Post spaces were prepared in 6 groups of 8 endodontically treated single-rooted teeth. Glass fiber-reinforced resin posts were airborne-particle abraded and luted after etching the canal dentin with phosphoric acid and/or applying XP Bond, Clearfil New Bond, or ED Primer. The groups with their respective etching time, primer, and cement combinations were as follows: XP15: 15 seconds of phosphoric acid treatment, XP Bond and Calibra; XP30: 30 seconds of phosphoric acid treatment, XP Bond and Calibra; NB15: 15 seconds of phosphoric acid treatment, Clearfil New Bond and Panavia 21; NB30: 30 seconds of phosphoric acid treatment, Clearfil New Bond and Panavia 21; ED: ED Primer only and Panavia 21; ED15: 15 seconds phosphoric acid treatment, ED Primer and Panavia 21. Specimens were stored in water for 30 days and subjected to simulated aging conditions. Post retention was measured in tension at a crosshead speed of 2 mm/min. Data were analyzed using Mann-Whitney and Kruskal-Wallis tests followed by post hoc comparisons using Langley method (alpha =.05). The dislodged posts and canals were examined microscopically at x8 and x20 magnification to evaluate the mode of failure. RESULTS: For each group, the mean (SD) retention in N was: XP15: 376.8 (39); XP30: 305.5 (27); NB15: 370.3 (31); NB30: 297.6 (52); ED: 301.6 (43); ED15: 373.8 (46). The retention values of ED15, NB15, and XP15 were significantly higher than those of ED, NB30, and XP30 groups, respectively. Microscopic evaluation demonstrated that the failure mode was primarily mixed. CONCLUSIONS: Luting posts with Panavia 21 or Calibra after etching the dentin with phosphoric acid for 15 seconds produced significantly higher retention values than treating dentin for 30 seconds or with ED Primer, only.

The prevalence and pattern of hypodontia of the permanent teeth and crown size and shape deformity affecting upper lateral incisors in a sample of Jordanian dental patients.

OBJECTIVE: The aim of this study was to determine the prevalence and pattern of hypodontia and the extent of congenital malformation in the permanent teeth of a sample of Jordanian adults. MATERIAL AND METHODS: Clinical examinations were carried out on 1045 dental patients aged 16 to 45 years to record any congenital absence of teeth except 3rd molars and to note any crown shape or size deformities affecting the upper lateral incisor. The congenital absence of permanent teeth was confirmed by taking complete dental history and orthopantomograms. Impacted teeth and teeth lost as a consequence of extraction or trauma were recorded as present. RESULTS: The prevalence of hypodontia was found to be 5.5% of the sample and the lower second premolar was the most frequently missing tooth. The number of missing upper lateral incisors was significantly higher than that of lower lateral incisors, (p < 0.05). Peg-shaped and reduced size upper lateral incisors were observed in 2.3% and 2.9% of the sample respectively. There were no significant differences according to gender, location of tooth according to arch or side of the jaw and hypodontic pattern. CONCLUSION: The prevalence of hypodontia was 5.5%, that of peg-shaped lateral incisor was 2.3% and that of reduced crown size was 2.9%.

Periodontal diseases and the risk of coronary heart and cerebrovascular diseases: a meta-analysis.

BACKGROUND: This meta-analysis was conducted to examine the relationship between periodontal diseases and coronary heart diseases (CHD) and cerebrovascular diseases (CVD) in observational studies. METHODS: This study was based on seven cohort studies and four studies of other designs that met prestated inclusion criteria. Information on study design, year of publication, study location, sample size, study population, participant characteristics, measurement of risk factors, exposure and outcome measures, matching, controlling for confounders, and risk estimates was abstracted independently by two investigators using a standard protocol. RESULTS: Subjects with periodontitis had an overall adjusted risk of CHD that was 1.15 times (95% confidence interval [CI]: 1.06 to 1.25; P = 0.001) the risk for healthy subjects. There was no heterogeneity among the studies in the overall relative risk estimate (P = 0.472). As compared to healthy subjects, those with periodontitis had an overall adjusted relative risk of CVD of 1.13 (95% CI: 1.01 to 1.27; P = 0.032). CONCLUSIONS: Findings indicated that periodontal infection increases the risk of CHD and CVD. However, this meta-analysis provided no evidence for the existence of strong associations between periodontitis and CHD and CVD. Larger and better-controlled studies involving socially homogeneous populations and measuring specific periodontal pathogens are required to identify a definite association between periodontal disease and the risk of coronary heart disease and cerebrovascular disease.

The surgical removal of mandibular third molars: a study in decision making.

OBJECTIVE: The aim of this study was to investigate and analyze the angulation of and the various indications for removal of mandibular third molars in Jordanians as a representative Arab sample. METHOD AND MATERIALS: The data included in this retrospective study were obtained from the clinical and radiographic records of 1,282 patients undergoing mandibular third molar surgery during a 5-year period from 1994 to 1999. The indications for removal of the mandibular third molars were classified in accordance with age and gender. The angular position of mandibular third molars was registered. RESULTS: A total of 2,252 mandibular third molars were removed from 740 male patients (57.7%) and 542 female patients (42.3%) aged 14 to 67 years. Pericoronitis was the most common indication for surgery, affecting 1,055 teeth (46.8%). Caries was observed in 519 third molars (23.0%). The vertical angular position was most commonly found (1,383 teeth; 61.4%) followed by the mesioangular position (407 teeth; 18.1%). CONCLUSION: The results obtained in this study are similar to those reported in earlier studies carried out elsewhere, although the incidence of periodontitis among Jordanians was significantly higher and occurred in older patients, and prophylactic removal was performed less frequently than has been reported in other countries.