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Clinical assessment of periodontitis in young adults--evaluation of probing depth and partial recording methods.

The present study was carried out to compare the ability of different methods of periodontal assessment to identify those subjects in a population who had suffered the worst periodontal breakdown. Comparisons were made between full mouth approximal attachment loss (CAL) assessment and methods relying on pocket probing depth (PPD) evaluation or on partial recording of CAL or PPD. Both of the latter types of assessment are commonly used in epidemiological surveys. 202 workers at an electronics factory aged between 20 and 40 yr were examined for approximal PPD and CAL, excluding third molars. The data were used to determine which individuals had the worst periodontitis based on CAL at several thresholds. Further analysis was carried out to determine which of these subjects would have been identified on the basis of the presence of deep (> or = 6 mm) pocketing, or by using one of a battery of partial recording subsets. CAL was frequently present in the absence of deep pocketing. A subset made up of four approximal sites around each of the 10 index teeth recommended by the WHO for partial recording (two molars in each quadrant and maxillary right and mandibular left central incisors) and a subset comprising maxillary buccal and mandibular lingual sites ("Pritchard" sites) performed best of the subsets considered in identifying the subjects who had been found by full mouth assessment to have at least one or at least two approximal sites with CAL at thresholds of 2, 3 or 4 mm. It was concluded that measurements of CAL using either of these subsets should reduce problems of under-recording of the prevalence of periodontitis associated with the use of PPDs alone or on CAL assessment at other partial recording subsets.

Adult↗

Reducing the bias of probing depth and attachment level estimates using random partial-mouth recording.

OBJECTIVES: To evaluate the bias and precision of probing depth (PD) and clinical attachment level (CAL) estimates of random and fixed partial examination methods compared with full-mouth examinations. METHODS: PD and CAL were calculated on six sites for up to 28 teeth (considered to be the gold standard with no bias) and three fixed-site selection methods (FSSMs) that resulted in a partial examination of sites: the Ramfjord method, and the NIDCR methods used in NHANES I, and NHANES 2000. Finally, seven random-site selection methods (RSSMs) were created by sampling the following number of sites: 84, 42, 36, 28, 20, 15, 10 and 6. To compare bias and precision of the methods we calculated percent relative bias and relative error. RESULTS: Estimates of means, standard deviations (SD), relative bias and relative error for RSSMs were almost identical to the full-mouth examination, but SDs increase slightly when fewer than 28 sites were sampled and relative bias and error increase for methods sampling fewer than 20 sites. The FSSMs had very low relative error, but much higher relative bias indicating underestimation. The FSSM with the smallest bias and error was the Ramfjord method, but the Random 36 method had less bias and less relative error. The NHANES 2000 method was the FSSM with the lowest bias and relative error for estimates of Extent Scores (percent of sites > or =3, 4, 5, or 5 mm PD or CAL) but random methods sampling fewer sites performed just as well. Both FSSMs and RSSMs underestimated prevalence, especially prevalence of less frequently occurring conditions, but most RSSMs were less likely to underestimate prevalence than the FSSMs. CONCLUSION: The promise of reducing bias and increasing precision of the estimates support the continued development and examination of RSSMs.

Aged↗

Multiple teeth showing invasive cervical resorption--an entity with little known histologic features.

Invasive cervical resorption is a relatively uncommon form of external root resorption, characterized by resorption of the cervical region of the root. There is progressive loss of cementum and dentine with replacement by fibrovascular tissue derived from the periodontal ligament, with deposition of cementum-like hard tissue. In most cases, a single tooth is involved. We report a case of invasive cervical resorption that resulted in loss of multiple teeth from two different quadrants. The case highlights the diagnostic difficulty that may arise in this uncommon lesion, the pathologic features of which may be mistaken for a fibro-osseous lesion or a low-grade sarcoma.

Adult↗

Irradiation effects on microhardness of fluoridated and non-fluoridated bovine dentin.

The objective of this study was to evaluate the effects of irradiation on microhardness of dentin. Dentin blocks from the cervical region of bovine incisors were treated as follows: (1) no irradiation; (2) irradiation of specimens up to 60 Gy (2 Gy/day, 5 days/week); (3) no irradiation, but fluoridation of specimens for 5 min/d; (4) irradiation of specimens and daily fluoridation. Knoop hardness number (KHN) of the control specimens was 62.63+/-14.75 (mean+/-SD). This was significantly different from the irradiated dentin samples (8.74+/-2.59 KHN). Hardness of the fluoridated dentin specimens was 11.19+/-1.95 KHN in the non-irradiated group and 10.03+/-2.76 KHN in the irradiated groups, respectively. Within the limitations of an in vitro study, it is concluded that dentin is severely affected by irradiation. This could be an explanation for the frequently observed side-effects of irradiation like loss of enamel, gap formation at the amelodentinal junction, and caries of the cervical region. Fluoridation with acidic gels decreases microhardness of dentin surface, and does not prevent softening due to radiation, when saliva is absent.

Animals↗

Comparison of bonding efficacy of an all-in-one adhesive with a self-etching primer system.

The aim of this study was to compare the bonding efficacy of an all-in-one adhesive with that of a self-etching primer system by measuring microleakage after thermocycling and the microtensile bond strength (microTBS) to enamel and dentin. Circular class V cavities along cement-enamel junctions were prepared in 20 extracted human premolars. Each 10 teeth were bonded with either AD Bond (AD) or Clearfil SE Bond (SE), and filled with a resin composite (Charisma). After thermocycling and staining with 0.5% basic fuchsin, the microleakage at the coronal and apical walls was evaluated using longitudinal sections. In addition 20 premolars were used to measure microTBS at 24 h after bonding for these adhesives to enamel and dentin that corresponded to the coronal and apical walls of the class V cavities. AD showed more microleakage than SE in the coronal walls, but there was less microleakage in the apical walls and no difference in apical leakage between the two adhesives. microTBS (SD) in MPa to enamel and dentin were 25.2 (7.3) and 68.3 (9.4) for AD, and 35.8 (7.4) and 76.4 (7.8) for SE, respectively. AD gave a lower microTBS to enamel than did SE. The results suggested that the poor adaptation at the coronal wall in AD might be caused by the lower bond strength to enamel.

Acid Etching, Dental↗

Undermining of enamel as a mechanism of abfraction lesion formation: a finite element study.

Many workers have suggested that abfraction lesion formation is caused by the physical overloading of enamel. However, an alternative mechanism, involving undermining of the cervical enamel along the amelodentinal junction (ADJ), may be a more realistic explanation. The aim of this study was to examine what effect undermining of the buccal cervical enamel would have on the stress distribution in upper teeth. Two-dimensional plain strain finite element meshes of an upper incisor, canine and first premolar and the supporting periodontal ligament and alveolar bone were developed. Each tooth was loaded with an oblique 100 N load, and the nodal maximum principal stresses (MPS) along a buccal horizontal sampling plane 1.1 mm above the amelo-cemental junction was measured. A discontinuity between the cervical enamel and dentine elements was then introduced (0.1 mm wide) using gap elements. The vertical extent of this defect varied from 0.1 to 0.5 mm. The value of the MPS varied from 1.8 to 209 Mpa, and the lowest values were found for the intact teeth (range 0.6-30.3 MPa). The discontinuity caused a dramatic increase in the numerical values of the MPS, and in many instances these exceeded the known failure stress for enamel.

Bicuspid↗

Class II restorations: influence of a liner with rubbery qualities on the occurrence and size of cervical gaps.

The aim of this study was to evaluate the ability of new rubbery liners, used as a cervical increment, to relieve contraction stress and thereby reduce the formation of cervical gaps in class II composite restorations. The investigated liners were made of polyester-acrylate (PE(1), PE(2) or PE(3)) or silicone-acrylate (S), mixed with UDMA, without (A, B, C, D) or with HEMA (AH, BH, CH, DH). A silanized filler was added to the mixture, DH, to give composites with 20, 40, 60, and 70% (w/w) of filler (DHF20, DHF40, DHF60, DHF70, respectively). The presence and width of cervical gaps were determined using a light microscope. Statistical analysis showed that six of the 12 rubbery liners (AH-DH, DHF20-DHF40) significantly decreased gap formation in comparison with the control group. In addition, the polymerization shrinkage, flow, and strain capacity of these liners were measured and the influence of these factors on gap formation was examined. Two- and three-dimensional regression analyses showed significantly negative linear correlations between gap formation and strain capacity, and between gap formation and flow, and a significantly positive linear correlation between gap formation and shrinkage.

Composite Resins↗

Role of cementoenamel junction on the radicular penetration of 30% hydrogen peroxide during intracoronal bleaching in vitro.

Intracoronal bleaching of nonvital, teeth with 30% hydrogen peroxide is occasionally associated with external cervical root resorption. The exact mechanism by which bleaching induced root resorption occurs is not yet fully understood. The relationship of cementum to the enamel at the cementoenamel junction may have clinical significance. Seventeen single rooted human mandibular premolars extracted atraumatically for orthodontic reasons were used. The radicular hydrogen peroxide penetration in each tooth was measured in vitro by an indirect colorimetric method. Thereafter, the teeth were examined with a scanning electron microscope to determine the type of the cementoenamel junction. It was found that the radicular penetration of 30% hydrogen peroxide was related to the type of cementoenamel junction.

Adult↗

Push-out strength and SEM evaluation of resin composite bonded to internal cervical dentin.

The bond strength of a resin composite used with a dual-cured dentin bonding system to internal cervical bovine dentin was evaluated using a direct or indirect placement technique. Teeth were sectioned transversely to produce 4 mm-thick specimens. The root canals were enlarged to a standardized taper, treated with a dentin bonding system, and filled with a light-cured resin composite using either direct, incremental composite placement or indirect composite placement of a pre-polymerized composite inlay. The debond stress of indirectly placed restorations using a composite inlay was 8.5 (SD +/- 2.7) MPa which was significantly greater (p < 0.0001) than the value of 5.0 (SD +/- 1.9) MPa for composite placed in a conventional, incremental manner. SEM evaluation revealed the indirect placement technique demonstrated increased resin tag density and length as compared to the direct technique. Enhanced retention of resin composite to endodontically prepared dentin treated with a dentin bonding system was obtained by using a composite inlay technique as opposed to direct, incremental buildup of the material.

Acid Etching, Dental↗

Comparison of two desensitizing agents for the treatment of cervical dentine sensitivity.

Numerous desensitizing agents have been utilized in an effort to alleviate the discomfort associated with cervical dentine sensitivity (CDS). Recently several new tubule-occluding and sealant systems have been marketed for treatment. The aim of this study was to compare two desensitizing agents (ALL-BOND 2 and Butler Protect) in a 3-month clinical study. Ten subjects (6F; 4M mean age 45.1 years (SD 8.81) who had provided voluntary written informed consent participated in a single-blind 3-month clinical study. Subjects were evaluated for tactile (Yeaple probe) and air sensitivity (dental air syringe) together with subjective perception of pain (VAS scores) at 0.5 min, 1, 2 and 3 months. There was an overall trend in reduction of CDS over the study period in all group with no significant differences detected between groups. The results suggested that while subjects reported overall reductions in sensitivity levels, this may not necessarily be substantiated when assessed objectively. Furthermore, there appeared to be a strong placebo effect in this study.

Adolescent↗

Efficacy of nightguard vital bleaching technique beyond the borders of a shortened tray.

PURPOSE: The purpose of this study was to determine if bleaching extends beyond the borders of a shortened tray or if a demarcation line is found. MATERIALS AND METHODS: Fifteen extracted teeth were selected darker than B2 on a Vita Lumin Shade guide (Vita Lumin, Bad Sackingen, Germany). The teeth were mounted in arch-like fashion in dental stone. Alginate impressions were made, and a stone replica of the four arches of teeth was generated. Vacuum-formed bleaching trays were fabricated for each arch, without and with reservoirs, as per the product to be tested. The nonreservoir trays were trimmed to one half the clinical crown length, and the reservoir trays were trimmed 1 mm beyond the border of the half-length reservoir. Measurements were taken from the cementoenamel junction (CEJ) to the tray border for each tooth. The trays averaged 5.1 mm short of the CEJ. The reservoir group was treated with viscous glycerin-based 10% carbamide peroxide (Opalescence, Ultradent Products Inc., South Jordan, Utah); the nonreservoir group with creamy dentifrice-based 10% carbamide peroxide (Platinum, Colgate Oral Pharmaceuticals, Canton, Massachusetts). The trays were loaded and fully seated on the teeth. Excess bleaching material was removed with a toothbrush and water rinse. Each assembly was placed in a humidor with incisal edges down to simulate oral conditions. The process was repeated for fourteen 6- to 8-hour bleaching sessions. Blinded and nonblinded operators determined post-bleaching shades, with consensus reached on differing shades. RESULTS: All teeth demonstrated lightening of 1 to 10 (mean 5.2) increments on the value-oriented shade guide. The bleaching effect extended beyond the tray and no demarcation lines were noted on any of the teeth. CLINICAL SIGNIFICANCE: This in vitro study suggests that successful bleaching occurs beyond the borders of inadvertently shortened trays. The clinician does not necessarily need to remake the tray if the tray does not cover all portions of the tooth.

Carbamide Peroxide↗

Potential for load-induced cervical stress concentration as a function of periodontal support.

PURPOSE: The purpose was to determine, photoelastically, the locations of occlusal load-induced stress concentrations within a maxillary premolar as a function of degree of periodontal support. MATERIALS AND METHODS: Composite three-dimensional models of a maxillary first premolar were fabricated for quasi-three-dimensional photoelastic stress analysis. Individual materials were used to model enamel, dentin, periodontal ligament, and alveolar bone. Three levels of periodontal support reduction (0%, 20%, 25%) were simulated by varying the socket depth. Vertical loads of 10 lb were applied to: (1) tip of buccal cusp, (2) tip of lingual cusp, and (3) center of occlusal surface. The resulting stresses were monitored and recorded photographically in the field of a circular polariscope arrangement. RESULTS: Cuspal loading concentrated stress around the cervical region below the loaded cusp, being highest under buccal cusp loading. The location of the stress concentration shifted apically as periodontal support diminished. CLINICAL SIGNIFICANCE: Observed cervical stress concentration corresponded well to the common location of abfractions seen in clinical situations. Since the location of cervical stress concentration varied with occlusal conditions, occurrence of abfractions must be highly dependent upon each patient's occlusion. Periodontal support reduction shifted the location of highest stress away from the cementoenamel junction. Therefore, abfractions are less likely to occur on periodontally compromised teeth compared to stable teeth.

Alveolar Process↗

Prevalence of noncarious cervical lesions and their relation to occlusal aspects: a clinical study.

PURPOSE: The purpose of this study was to assess noncarious cervical lesions in young patients and to establish a possible relation with occlusal aspects. MATERIALS AND METHODS: Forty-eight dental students (28 males; 20 females) between the ages of 16 and 24 years, were investigated to verify the presence of noncarious cervical lesions and their relation to some occlusal aspects. The assessment involved a questionnaire, clinical examinations, and model analysis. RESULTS: The results indicated that the lower first molars (21.3%), the upper first molars (16.0%), the upper first premolars (12.8%), the lower first premolars (11.7%), and the lower second premolars (11.7%) were the teeth most affected by the lesions. Age was a significant factor with respect to the presence of lesions; the students with noncarious cervical lesions were older than the students who showed no lesions. Among the 79 teeth exhibiting lesions, 62 (78.5%) showed wear facets. In the group with lesions, the mean, per subject, was 15.0 teeth with wear facets, whereas in the group without lesions the mean was 10.8 teeth with wear facets per subject, suggesting that occlusal stress has some effect on lesion development.

Adolescent↗

Safety and stability of nightguard vital bleaching: 9 to 12 years post-treatment.

PURPOSE: The purposes of this retrospective case series study were to evaluate safety issues and determine participants' perceptions of a nightguard vital bleaching (NGVB) technique approximately 10 years post-treatment (average, 118 mo; range, 108-144 mo). MATERIALS AND METHODS: The study sample included 30 (79%) of 38 participants who had completed a previous NGVB study using a 10% carbamide peroxide solution (Proxigel or Gly-Oxide) in a custom tray for 6 weeks. Participants were asked whether there had been any change in the shade of their teeth post-treatment and, if so, to quantify the change on a verbal scale. In addition, 19 participants had gingival index and tooth vitality evaluated clinically, external cervical root anatomy evaluated radiographically, and enamel surface changes evaluated microscopically. RESULTS: Thirty-five (92%) of the original 38 participants had successful lightening of their teeth. At approximately 10 years post-treatment (average, 118 mo; range, 108-144 mo), external cervical resorption was not diagnosed and gingival index and tooth vitality findings were considered within the normal expectations for the sample studied, suggesting minimal clinical post-NGVB side effects at approximately 10 years. Scanning electron microscopic observations did not reveal substantial differences between treated and nontreated surfaces. Color stability, as perceived by 43% of the participants, may last approximately 10 years (average, 118 mo; range, 108-144 mo) post-treatment. CLINICAL SIGNIFICANCE: Nightguard vital bleaching using 10% carbamide peroxide is safe and effective, with no noticeable side effects, at approximately 10 years (average, 118 mo; range, 108-144 mo) post-treatment. Color stability, as perceived by 43% of the participants, may last 108 to 144 months post-whitening.

Adult↗

Esthetic noncarious Class V restorations: a case report.

UNLABELLED: When restoring anterior and posterior teeth affected by noncarious cervical lesions, many clinicians overlook the etiologic factors responsible for the lesions' development, resulting in frequent restorative failures. The treatment approach for noncarious cervical lesions must not be based only on restorative procedures since a variety of causative and aggravating factors are related to their formation. This article discusses a treatment protocol and techniques for the restoration of noncarious Class V lesions and presents a clinical case in which esthetic restorations are achieved. CLINICAL SIGNIFICANCE: Treatment options for noncarious Class V lesions can range from simply eliminating the causative factors of the lesions and regularly monitoring their progression to specific restorative procedures. Resin composites are the best materials for restoring cervical defects owing to their bonding ability, physical properties, and esthetic potential. A straightforward technique for the successful restoration of noncarious Class V lesions is presented.

Bruxism↗

Incidence of noncarious cervical lesions and their relation to the presence of wear facets.

PROBLEM: Noncarious cervical lesions are characterized by loss of tooth structure in the cervical area, compromising its integrity and resulting in esthetic problems for the patient. PURPOSE: The purpose of this study was to assess noncarious cervical lesions in young patients in an attempt to establish a possible relationship to the presence of wear facets. MATERIALS AND METHODS: First-year dental students of Bauru Dental School were studied to verify the prevalence of noncarious cervical lesions and their relationship to the presence of wear facets. After 3 years, the students were examined again to verify the incidence of new lesions, trying to establish a correlation to the previous existence of wear facets. RESULTS: Of the 1,131 teeth analyzed, 129 had noncarious cervical lesions. Twenty-nine of the 40 students had at least one tooth with one lesion. After 3 years, the incidence of new lesions was 57. Mandibular first molars (22.3%), mandibular first premolars (13.2%), mandibular second premolars (13.2%), and maxillary first molars (12.4%) showed the highest prevalence of lesions. On final analysis, 86.8% of all teeth presenting lesions showed wear facets. The identification of new lesions associated with the presence of wear facets identified during the first exam 3 years earlier was statistically significant (p < 0.01). CONCLUSIONS: The patterns of wear facets found in the study population examined were associated with an increased occurrence of noncarious cervical lesions. CLINICAL SIGNIFICANCE: Occlusal factors, especially the presence of wear facets, should be considered in the management of noncarious cervical lesions.

Adolescent↗

Treatment of invasive cervical resorption with MTA: case report.

This paper presents a case report of a maxillary lateral incisor affected by invasive cervical resorption. The tooth was submitted to a 21-day treatment with calcium hydroxide followed by root canal filling. The area of resorption was sealed with MTA followed by glass ionomer cement and restored with composite resin. Two-year radiographic follow-up showed stability of the resorption site and normal coronal colour and depth of gingival sulcus.

Adult↗