Serum microRNAs as potential biomarkers of mandibular prognathism.

OBJECTIVES: The aim of the study was to determine whether the expression levels of specific circulating serum microRNAs (miRNAs) are associated with mandibular prognathism (MP). METHODS: Sixty subjects in the early permanent dentition stage and 23 in the mixed dentition stage with MP were identified. Sixty-eight normal control subjects in the early permanent dentition stage and 24 in the mixed dentition stage were recruited for comparison. According to the microarray-based expression profiling, four serum miRNAs (let-7i-3p, miR-595, miR-16-2-3p, and miR-367-5p) were validated. RESULTS: In the MP groups, let-7i-3p was significantly over-expressed in subjects in the early permanent (P < 0.0005) and mixed (P < 0.001) dentitions, and miR-595 was significantly under-expressed (P < 0.004) in subjects in the early permanent (P < 0.004) and mixed (P < 0.0005) dentitions, compared with normal control groups. Multiple logistic regression analysis and receiver operating characteristic curve analysis revealed that let-7i-3p and miR-595 were able to significantly discriminate MP subjects from normal controls. CONCLUSION: Let-7i-3p and miR-595 could be potential, non-invasive biomarkers for the accurate early detection and diagnosis of MP, which may result in improved clinical management.

Oral diagnosis and treatment planning: part 8. Reviews and maintenance of restorations.

The oral environment is hostile to dental materials and to dental treatments. Microorganisms, warmth, moisture and high stresses impose severe limitations on the ability to maintain the initial results of dental treatment. Therefore, continuous periodic reviews and maintenance of oral health are required to retain the restored dentition.

Oral diagnosis and treatment planning: part 7. Treatment planning for missing teeth.

Although more people are retaining increasing numbers of their natural teeth into older ages, approximately 30-40% of persons over the age of 75 years in Western countries are edentulous. The causes and significance of tooth loss vary widely among individuals and cultures, and missing teeth may be replaced by a variety of means for functional, social and psychological reasons, rather than for significant physical health benefits. Therefore, it is essential to determine what the loss of teeth means to patients and what their expectations are for the outcomes following tooth replacement by various methods.

Oral diagnosis and treatment planning: part 5. Preventive and treatment planning for dental caries.

The practice of operative dentistry continues to evolve, to reflect the many changes occurring in society and in dental diseases and conditions. However, the belief that all questionable and early carious lesions should be restored still persists. This belief is largely based upon the concept that the removal of all carious tissue followed by meticulous restoration of the tooth is the treatment of choice for dental caries. Yet restorations are not permanent and do not cure caries, as the causes remain. On the other hand, preventive measures can remove or partially remove the causes, thereby reducing the risks for future caries recurrence at the same site or elsewhere in the mouth.

Oral diagnosis and treatment planning: part 6. Preventive and treatment planning for periodontal disease.

A high level of sustained personal plaque control is fundamental for successful treatment outcomes in patients with active periodontal disease and, hence, oral hygiene instructions are the cornerstone of periodontal treatment planning. Other risk factors for periodontal disease also should be identified and modified where possible. Many restorative dental treatments in particular require the establishment of healthy periodontal tissues for their clinical success. Failure by patients to control dental plaque because of inappropriate designs and materials for restorations and prostheses will result in the long-term failure of the restorations and the loss of supporting tissues. Periodontal treatment planning considerations are also very relevant to endodontic, orthodontic and osseointegrated dental implant conditions and proposed therapies.

Oral diagnosis and treatment planning: part 2. Dental caries and assessment of risk.

Dental caries or tooth decay may be defined as a dynamic process causing progressive destruction of hard tooth substance (enamel, dentine and cementum) involving demineralisation of the inorganic portion of the tooth, and dissolution of the organic portion. The onset and progression of carious lesions involves multiple host, micro-organism and substrate factors interacting in a continuous flux. The diagnosis of initial lesions remains a challenge for practitioners and, despite numerous studies, the assessment of future caries risk is still based largely on a patient's past caries experience. If caries is allowed to progress then pulpitis will occur, which may result in subsequent pulpal necrosis and lead to a local periapical and perhaps a systemic infection.

Oral diagnosis and treatment planning: part 1. Introduction.

A good manageable treatment plan does not just happen, but comes about as the natural consequence of taking carefully considered steps. History taking and clinical examination are two of the most important aspects of the patient assessment process, and complement each other to such an extent that it is impossible to build a satisfactory treatment plan without combining and collating information from the two procedures.

Patterns and forces of occlusal contacts during lateral excursions recorded by the T-Scan II system in young Chinese adults with normal occlusions.

The objective was to characterise the patterns and forces of occlusal contacts during lateral mandibular excursions in a young Chinese adult population. Angle Class I normal occlusions in 85 dental students aged 20-29 were evaluated using the T-Scan II occlusal imaging and analysis system. The frequency of occlusal contacts was recorded for right and left lateral excursions at the position of lateral disclusion, at the canine-to-canine position and at the lateral maximal position. At the canine-to-canine position, the occlusal contact patterns were classified, and the relative forces were compared by multiple regression analysis, with α = 0·05. At the position of lateral disclusion, a high percentage of canine contacts (58·5%) and individual posterior tooth contacts on the working side was observed. At the canine-to-canine position, the canines on the working side contacted most frequently (68·9%), and the occlusal contact patterns could be classified into six groups. At the lateral maximal position, incisors (39·0%) and canines (32·3%) contacted most frequently. At the canine-to-canine position, subjects with occlusal contacts only on canines or on first premolars on the working side had the lowest relative occlusal forces (P < 0·001). Canine protection and group function do not identify all descriptors for lateral occlusal contact patterns in the natural dentition. Six occlusal contact patterns were found at the lateral canine-to-canine position.

Effect of fluoride iontophoresis on the microtensile bond strength between dentin and two adhesive systems.

AIM: To evaluate the effect of fluoride iontophoresis on the microtensile bond strength (MTBS) between coronal dentin and two resin-based adhesive systems, and to measure quantitatively dentinal tubule occlusion. METHODS: Twelve freshly extracted intact human mandibular third molars were divided randomly into four groups. The superficial occlusal dentin of each tooth was exposed and treated. Group A1: One-Step Plus total-etch adhesive system; group A2: One-Step Plus total-etch adhesive system after fluoride iontophoresis; group B1: ACE BOND SE self-etching adhesive system; group B2: ACE BOND SE self-etching adhesive system after fluoride iontophoresis. A resin composite buildup was made for each tooth, which was then sectioned along its long axis to produce 10 beams (1.0 mm x 1.0 mm) for the microtensile bond strength (MTBS) test. Five dentin disks were cut in half and their occlusal surfaces etched with 6% citric acid. The test halves were treated with fluoride iontophoresis. Four SEM photomicrographs were taken from corresponding sites on each test and each non-treated control half-disk. Image-Pro Plus 4 software quantified the percentage of tubule occlusion. Data were analyzed using one-way ANOVA, chi(2)- and t-tests, with the probability level set at alpha=0.05. RESULTS: The mean MTBS (MPa) for each group was, A1: 30.86 (S.D. 6.84); A2: 25.04 (8.49); B1: 19.22 (6.88); B2: 19.40 (6.92). There were significant differences among all groups (P < or = 0.02), except between groups B1 and B2 (P=0.92). Fluoride iontophoresis resulted in significantly increased dentinal tubule occlusion (P<0.001). CONCLUSIONS: Fluoride iontophoresis treatment reduced significantly the dentin bond strength of One-Step Plus total-etch adhesive, but not that of ACE BOND SE self-etching adhesive. However, the bond strength of the former remained significantly higher than that of the latter adhesive system.

Radiation-induced root surface caries restored with glass-ionomer cement placed in conventional and ART cavity preparations: results at two years.

BACKGROUND: There are no published studies comparing the clinical performances of more-viscous glass-ionomer cement (GIC) restorations when placed using conventional and atraumatic restorative treatment (ART) cavity preparation methods to restore root surface caries. METHODS: One dentist used encapsulated Fuji IX GP and Ketac-Molar to restore 72 conventional and 74 ART cavity preparations for 15 patients who had received cervicofacial radiation therapy. Two assessors evaluated the restorations at six, 12, and 24 months for retention, marginal defects and surface wear, and recurrent caries. RESULTS: After two years, the cumulative restoration successes were 65.2 per cent for the conventional and 66.2 per cent for the ART cavity preparations, without statistical or clinical significance (P > 0.50). Restoration dislodgement accounted for 82.8 per cent and marginal defects for 17.2 per cent of all failures. There were no instances of unsatisfactory restoration wear or recurrent caries observed. Teeth with three or more restored cervical surfaces accounted for 79.3 per cent of all failures (P < 0.0001). CONCLUSIONS: For root surface caries restored with GIC, the use of hand instruments only with the ART method was an equally effective alternative to conventional rotary instrumentation for cavity preparation. Larger restorations had higher failures, usually from dislodgement.

Prosthodontic management of older severe hypodontia patients in general dental practice: a case series.

Although a detailed understanding of the etiology of hypodontia is lacking, there is a need for awareness among dental professionals of the social and psychological consequences of severe hypodontia, as well as knowledge of those affected by hypodontia have ongoing dental treatment needs. Although, there may be a need for immediate referral of children to different specialists for optimal multidisciplinary treatment planning, most older patients with severe hypodontia can be treated by general practitioners. Practitioners therefore need to be aware of the ramifications of the condition and be capable of providing adequate oral health care for these patients and referring them for additional services when necessary. A case-report series is used to illustrate routine prosthodontic treatments that can be offered to older patients in general dental practice.

Placement and replacement of dental restorations.

OBJECTIVE: To determine the types of various dental restorative materials used, and the reasons for the placement and replacement of dental restorations in 10 randomly selected polyclinics in Riyadh, Saudi Arabia. DESIGN: A cross-sectional descriptive study. PLACE AND DURATION OF STUDY: Ten selected polyclinics in Riyadh metropolitan area, Saudi Arabia during a period of two weeks in January 2003. PATIENTS AND METHODS: Information was collected by using a specially-designed form that was distributed to one dentist in each selected polyclinic. The dentists were asked to record specific details for all restorations placed in adult patients. Chi-square tests were used to analyze the data. RESULTS: Data were collected for 326 restorations. Amalgam (52.5%) was the most commonly used restorative material followed by resin composite (31.3%) and temporary restorations (14.4%), with a minimal use of glass ionomer cement (1.8%, p<0.001). Most of the restorations (69.9%) were initial placements, while 30.1% were replacement restorations, (p<0.05). Caries was the major reason for the initial placement (92.1%), and for the subsequent replacement (96.9%) of restorations. CONCLUSION: Amalgam and resin composite were the most commonly used restorative materials. Caries was the major reason for the initial restoration placements and subsequent replacements.

Diagnostic comparison of three groups of examiners using visual and laser fluorescence methods to detect occlusal caries in vitro.

BACKGROUND: To evaluate the accuracy of the DIAGNOdent laser device (DD) for detecting occlusal fissure caries when used by three groups of examiners. METHODS: Three final-year dental students (S), three General Dental Practitioners (G), and three Academic Clinicians (A) individually examined the non-cavitated occlusal surfaces of 25 extracted permanent molars using visual inspection (VI) then DD assessments. The presence of caries was confirmed following tooth sectioning. A cut-off limit of 30 was used for the DD to avoid over-treatment in a low caries-risk situation. RESULTS: For VI, individual examiner sensitivity (caries correctly diagnosed) ranged from 53 to 86 per cent, and specificity (sound teeth correctly diagnosed) ranged from 76 to 95 per cent, with low Kappa agreements. Group S achieved the highest sensitivity (80 per cent) and Groups G and A achieved the highest specificities (88 per cent). For DD, individual examiner sensitivity ranged from 19DD, individual examiner sensificity ranged from 19 to 77 per cent, and specificity from 71 to 97 per cent, with generally moderate Kappa agreements. Group A achieved the highest (67 per cent) and Group G the lowest (44 per cent) sensitivities, and Group G achieved the highest specificity (94 per cent). CONCLUSIONS: There were similar widely varying results for the two diagnostic methods and for the three groups of examiners. However, the relatively high sensitivities found with VI and specificities found with DD should avoid over-treatment in low caries-risk populations.

Long-term cost-effectiveness of single indirect restorations in selected dental practices.

OBJECTIVE: To determine the relative cost-effectiveness of alternative methods for restoring large tooth substance loss in adults. METHODS: Long-term survival estimates and discounted costs for 245 large indirect restorations were used to calculate their incremental cost-effectiveness over 15 years when compared with direct placement Class II cusp-overlay amalgams and Class IV multisurface resin composites, placed in 100 patients from three private dental practices. RESULTS: The direct placement restorations were more cost-effective than the indirect restorations at all time intervals over the 15-year study period. The full gold crown and the ceramometal crown were the most cost-effective indirect posterior and anterior restorations respectively. The cast gold onlay and the porcelain jacket crown were the least cost-effective indirect posterior and anterior restorations respectively. CONCLUSIONS: When clinically practicable, large direct placement restorations should be placed initially in preference to indirect restorations.

Survival of glass ionomer restorations placed in primary molars using atraumatic restorative treatment (ART) and conventional cavity preparations: 2-year results.

OBJECTIVE: To compare the survival of glass ionomer cement (GIC) restorations placed in a dental clinic setting using both the atraumatic restorative treatment (ART) approach with hand instruments, and conventional cavity preparation with rotary instruments. METHOD AND MATERIALS: Two encapsulated high-strength conventional GICs (Fuji IX GP, Ketac-Molar Aplicap) were placed in 82 Class I and 53 Class II preparations and one encapsulated non-gamma 2 amalgam alloy (GK-amalgam) was placed in 32 Class I preparations, in the primary molars of 60 Chinese children with a mean age of 7.40 +/- 1.24 (SD) years. Thus, 9 treatment groups were formed. RESULTS: After two years, there were no significant survival differences found among 7 of the 9 treatment groups (p = 0.99). However, two groups comprising Fuji IX GP and Ketac-Molar Aplicap placed in Class II cavities prepared using the ART approach showed significantly lower restoration survivals (p < 0.001). Only 3 of the 72 initially sealed fissures adjacent to the restorations appeared to retain any GIC material. CONCLUSIONS: In a clinic setting, both the ART hand instrument and conventional rotary instrument methods were equally suitable for high Class I restoration survival, but not for Class II restoration survival where the conventional cavity preparation method was preferable.

Longevity of a resin-modified glass ionomer cement and a polyacid-modified resin composite restoring non-carious cervical lesions in a general dental practice.

BACKGROUND: Long-term prospective survival studies of resin-modified glass ionomer cements (RMGICs) and polyacid-modified resin composites (compomers) placed in non-carious cervical lesions (NCCLs) are lacking from general dental practice. Short-term studies have shown an unsatisfactory clinical performance for several materials. METHODS: One practitioner placed 87 compomer (Compoglass, Vivadent-Ivoclar) and 73 encapsulated RMGIC (Fuji II LC, GC Int.) restorations in NCCLs for 61 adults. Compoglass was placed using SCA primer, and Fuji II LC using GC Dentin Conditioner. No cavity preparation was undertaken. The Kaplan-Meier method was used for estimating the cumulative survivals for those restorations that were replaced, with the probability level set at alpha = 0.05 for statistical significance. RESULTS: Restorations were judged unsatisfactory (by the practitioner and the subjects) because of surface and marginal loss of material (68.8 per cent), dislodgement (18.8 per cent) and discoloration (12.4 per cent), these modes being similar for both materials (P = 0.35). Unsatisfactory restorations were replaced in 121 (75.6 per cent) instances. After periods of up to five years, cumulative survival estimates were 14.9 (5.8 Standard Error) per cent for Compoglass and zero per cent for Fuji II LC (P = 0.74). Median survivals were 30 months for Compoglass and 42 months for Fuji II LC. CONCLUSION: Both materials had high long-term unsatisfactory performances when placed in non-prepared NCCLs in a general dental practice.

Comparison of pulpal sensitivity between a conventional and two resin-modified glass ionomer luting cements.

This clinical study compared handling and any short-term tooth sensitivity associated with using one conventional and two resin-modified glass ionomer cements marketed for luting gold and ceramometal crowns. The patient's response to a 10-second blast of air applied to the vital tooth was scored pre-operatively and again within a one-to-four week post-cementation recall period. A score was also recorded for any sensitivity present at the time of cementation of the crown on the unanesthetized tooth. All three cements were easy to mix and place. Most of the teeth had no response to pulpal stimulation pre-operatively, associated with the cementation procedure or post-cementation, and there were no instances of severe sensitivity recorded. For all cements, the level of post-cementation tooth sensitivity was similar, and less than that found pre-operatively.

Micro-tensile bond strengths to sclerotic dentin using a self-etching and a total-etching technique.

OBJECTIVES: To evaluate the in vitro regional micro-tensile bond strengths of a self-etching/self-priming adhesive system to sclerotic dentin, in the absence or presence of phosphoric acid conditioning. METHODS: Naturally-occurring, non-carious cervical lesions on extracted premolars were hand-cleaned with a slurry of pumice and chlorhexidine, then bonded without further cavity preparation. One group was bonded using Clearfil Liner Bond 2V (Kuraray Co. Ltd., Osaka, Japan). The other group was first conditioned with K-etchant; 40% phosphoric acid gel (Kuraray) prior to the application of the self-etching primer. Artificially prepared wedge-shaped cavities were also made in sound premolars and bonded with the two methods as controls. Resin composite build-ups were made using Clearfil Protect Liner F and AP-X resin composite (Kuraray). After storage in water for 24h, the teeth were sectioned into 0.7 x 0.7 mm composite-dentin beams along the occlusal and gingival walls, and at the apex of the lesions. The use of two conditioning methods, two substrate types, and three different locations yielded 10-14 beams for each of the 12 groups. After testing for the microTBS, representative beams that were stressed to failure were examined with SEM. Remaining fractured beams were demineralized and processed for TEM examination. Statistical analysis was performed using a three-way ANOVA and Student-Newman-Keuls tests. RESULTS: Regardless of the conditioning methods, bond strengths to sound dentin were significantly higher than to sclerotic dentin (P< 0.05). With sclerotic dentin, there was no significant difference for the conditioning methods used, except that K-etchant significantly improved the bond strength at the gingival aspect of the lesions. Fractographic analysis revealed that the self-etching primer could not etch beyond the surface hypermineralized layer of sclerotic dentin. Interfacial failure occurred along the surface of the mineralized intermicrobial matrix and/or hypermineralized layer. With the use of phosphoric acid, a hybrid layer was only seen when the surface layers were thin. Incompletely removed sclerotic casts were evident in both groups. SIGNIFICANCE: Removal of the surface layers of sclerotic dentin and/or conditioning with stronger acids may be beneficial to obtain stronger bonding to sclerotic dentin.

Glass ionomer cements used as fissure sealants with the atraumatic restorative treatment (ART) approach: review of literature.

AIM: To review the success of newer, more-viscous aesthetic conventional glass ionomer cements (GICs), that have been marketed specifically for the atraumatic restorative (ART) technique or approach, when used as pit and fissure sealants. As part of this approach, enamel fissures adjacent to the ART restorations are conditioned with poly (acrylic) acid (PAA) and then usually sealed with a GIC, using the finger-press method. RESULTS: The newer GICs appear in vitro to penetrate adequately and seal occlusal fissures in permanent molar teeth, and clinical studies of the ART approach over three years have found sealant retention (full and partial) to be approximately 70%, with fissure caries approximately 0-4%. In two studies, fissure caries was significantly reduced in sealed as compared with unsealed teeth over three years. CONCLUSIONS: Although the results appear to be better with the newer than with earlier conventional GIC products, the ART studies have generally involved populations at low-risk to caries, and further improvements in the mechanical properties of the cements are required for optimal long-term clinical success. Etching the enamel fissures with phosphoric acid, instead of conditioning with PAA, before GIC sealant placement warrants clinical investigation.

Restoration of teeth with more-viscous glass ionomer cements following radiation-induced caries.

OBJECTIVE: To assess the suitability of more-viscous conventional restorative glass ionomer cements (GICs) in a high-caries risk group of patients. METHODS: Fifteen adult patients with radiation-induced caries were treated at a dental hospital by one dentist. Two encapsulated aesthetic GICs were used in each patient to restore 146 carious lesions in the exposed dentine and cementum of 93 teeth. The restorations were assessed directly over two years for their retention, secondary caries, anatomic form, marginal integrity, marginal discolouration, and surface texture. RESULTS: Both GICs were placed in similar sized cavities (P = 0.63). After two years, although 30.0% of Ketac-Molar Aplicap and 12.5% of Fuji IX GP restorations had been lost (P = 0.01), there were no instances of secondary caries. The remaining GICs showed ongoing marginal deterioration, but there were very few instances where this required the repair or replacement of the restorations. No restorations failed from surface erosion. CONCLUSIONS: In these high-caries risk patients the placement of more-viscous GICs appeared to prevent secondary caries, even when the restorations were subsequently lost.