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PubMed2001

The effect of moisture and blood contamination on bond strength of a new orthodontic bonding material.

The practice of orthodontics often requires the bonding of brackets under difficult conditions of moisture and/or blood contamination. Transbond MIP (3M Unitek, Monrovia, Calif) is a hydrophilic primer designed to bond in moist conditions. This study evaluated the bond strength of Transbond MIP under dry, moist, and blood-contaminated conditions. Ninety human premolars were bonded in 3 equal groups with Transbond MIP after acid etching; the enamel surfaces were either dry, moist, or contaminated with human blood. The shear bond strength was recorded. Dry bonding resulted in a significantly higher bond strength (15.69 MPa) than moist (12.89 MPa) or blood-contaminated (11.16 MPa) bonds. However, all bond strengths were in excess of previous reports of required clinical bond strength, and it was concluded that Transbond MIP is a suitable adhesive for bonding in conditions of poor moisture control or blood contamination.

Acid Etching, Dental↗
PubMed2002

Orthodontic treatment outcome in a First Nations population in Alberta, Canada: a comparative study.

The primary objective of this study was to determine whether there was a significant difference in the degree of improvement after orthodontic treatment between a sample of First Nations orthodontic patients and a control sample of non-First Nations orthodontic patients. The secondary objective was to determine whether there was a difference in the severity of malocclusions being treated in a sample of the First Nations patients compared with a control sample of the non-First Nations patients. Several factors that might affect treatment outcome, such as missed appointments, treatment duration, oral hygiene, extractions, dental classification, and geographic location, were also studied. A sample of 60 First Nations patients and a control group of 60 non-First Nations patients between the 11 and 18 years of age who had been treated with full fixed orthodontic appliances were evaluated. The weighted peer assessment rating (PAR) index was applied to pretreatment and posttreatment study models to address the study's main objectives. The results showed that the First Nations group had greater PAR scores pretreatment than did the controls, and their weighted PAR scores improved more with treatment. Posttreatment PAR scores were similar between the 2 groups. In addition to First Nations status, only extractions and geographic location affected PAR improvement scores.

Adolescent↗
PubMed2002

Accuracy of patient reporting as an indication of headgear compliance.

Orthodontists struggle daily with the issue of patient compliance. Often, we must rely on patient cooperation with headgear to correct Class II malocclusions. Because there is no way to objectively and accurately gauge headgear cooperation, we must look for clues in assessing compliance. One clue that we use is the patient's own reporting of headgear wear. This study was aimed at determining the accuracy of patient reporting. Twenty patients in a private orthodontic practice were supplied with electronic timing headgears that enabled the author to compare their reported hours of headgear use with electronically measured actual usage. In this sample, 69% of the patients reported their headgear use at an accuracy level of 84% or greater, while 31% reported their use at an accuracy level of 58% or less. If fully one third of our patients are significantly inaccurate in reporting headgear use, this has clear implications in patient education, expected treatment results, and informed consent. Some may consider the timing headgear a useful adjunct in promoting better patient compliance.

Child↗
PubMed2002

Shear bond strength of rebonded mechanically retentive ceramic brackets.

The purpose of this study was to evaluate the bond strength of rebonded mechanically retentive ceramic brackets. Twenty new and 100 sandblasted rebonded ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) were bonded to 120 extracted human premolars with composite resin and divided into 6 equal groups according to how the bracket bases were treated: (1) new brackets, (2) rebonded/sandblasted, (3) rebonded/sandblasted/sealant, (4) rebonded/sandblasted/hydrofluoric acid (HF), (5) rebonded/sandblasted/HF/sealant on bracket base, and (6) rebonded/sandblasted/silane. Shear bond strength of each sample was tested with a testing machine. Results showed that the new brackets group had the highest mean strength (15.66 +/- 7.05 megapascals [MPa]), followed by the rebonded/sandblasted/sealant group (7.65 +/- 5.62 MPa), the rebonded/sandblasted/silane group (5.94 +/- 5.33 MPa), the rebonded/sandblasted group (2.97 +/- 2.29 MPa), the rebonded/sandblasted/HF group (1.22 +/- 1.66 MPa), and the rebonded/sandblasted/HF/sealant group (0.82 +/- 1.16 MPa). Statistical analysis showed that only the rebonded/sandblasted/sealant group was comparable with the new brackets group in bond strength (P >.05). It was concluded that in the process of rebonding mechanically retentive ceramic brackets, (1) new brackets have the highest mean bond strength when compared with rebonded brackets, (2) the bond strength of sandblasted rebonded brackets with sealant is not significantly different from new brackets, (3) silane does not increase bond strength of rebonded brackets significantly, and (4) HF treatment on sandblasted rebonded brackets significantly decreases bond strength.

Acid Etching, Dental↗
PubMed2002

Comparative bond strength of brackets cured using a pulsed xenon curing light with 2 different light-guide sizes.

Light curing of composite resin material beneath orthodontic brackets is common in clinical orthodontics. Experiences with composite resins and high-intensity lights indicate some advantages to staged curing of the composite. In this study, the shear/peel bond strength of orthodontic brackets bonded to bovine enamel and cured with a pulsed xenon plasma arc light was compared with that of bonds cured with a conventional tungsten-quartz-halogen light and a nonpulsed xenon plasma arc light. The pulsed light provided less light energy than the nonpulsed lights. A small and a larger light-guide tip were used with the pulsed xenon plasma arc light. Three different orthodontic composite resin adhesives were tested with each light. The pulsed xenon plasma arc light resulted in either the same or decreased shear/peel bond strength when compared with the nonpulsed lights. There appeared to be no advantage to the use of a pulsed xenon plasma arc light in bonding orthodontic brackets. Results from using either a small or a large light-guide tip varied with the adhesive tested.

Acid Etching, Dental↗
PubMed2003

Comparison of radiographic and photographic measurement of mandibular asymmetry.

This study compared measurement of mandibular asymmetry by digitization of mandibular outlines from standardized facial photographs and posteroanterior cephalometric radiographs. Four ratios were used in calculating asymmetry: area (relative size of right and left mandibular segments), perimeter or length of outlines, compactness (shape), and moment. The records of 28 patients with varying degrees of asymmetry were used. A significant relationship was found for 3 of the ratios (area, compactness, and moment) between measurements from photographs and radiographs. A further comparison showed that measurements from the radiographs correlated more closely with those from photographs when the mastoid processes were used as a baseline, rather than latero-orbitale. Repeatability of mandibular outline digitization proved satisfactory. Although digitization from standardized photographs is the preferred approach, the results indicated that posteroanterior cephalometric radiographs can be used similarly. Unlike other cephalometric analyses for mandibular asymmetry, this method avoids problems of landmark identification, thus presenting a clinically useful method of quantifying asymmetry, eg, in auditing the surgical-orthodontic correction of asymmetry or monitoring change over time.

Adult↗
PubMed2003

Reproducibility of natural head position measured with an inclinometer.

Sagittal (pitch) and transversal (roll) natural head position (NHP) was measured once in 20 subjects, 18 to 24 years of age, with an inclinometer; the measurements were repeated 2 years later. The method error (reproducibility) after 2 years was 1.1 degrees for sagittal and transversal measurements. The mean change in NHP measurement was -0.3 degrees for both measurements, and the variance was 1.21 degrees (= 1.1(2)).

Adolescent↗
PubMed2001

Gender differences in human immunodeficiency virus-related oral lesions: an Italian study.

OBJECTIVE: The purpose of this study was to investigate the relationship between oral lesions and gender, age, CD4(+) cell count, human immunodeficiency virus-1 (HIV-1) viral load, antiretroviral therapy, and route of transmission in a group of HIV-infected (HIV+) persons from the Mediterranean region. STUDY DESIGN: The participants in this study were HIV+ adults who sought dental care between January 1999 and June 1999 in the Department of Oral Medicine (University of Palermo, Italy). RESULTS: One hundred thirty-six HIV+ adults came in for an initial oral examination. Their mean age was 35.2 years (SD +/- 7.97), and 33% were women. Their mean CD4(+) cell count was 325.3 x 10(6) /L (SD +/- 225.8), and their HIV-1 viral load was 39,168.3 copies/mL (SD +/- 144,256.1). Oral lesions were found in 47% of the study group, as well as in 56.5% of women (n = 46) versus 45.5% of men (n = 90; P =.05). Oral candidiasis was the most common disease; it is significantly associated with women (P =.004), CD4(+) cell count (P =.005), and HIV-1 viral load (P =.0003). No significant relationships were found between any types of oral lesions and age, antiretroviral therapy, or route of transmission (P >.2). CONCLUSION: The prevalence of HIV-related oral lesions was significantly higher in women than in men, especially for oral candidiasis, the most common lesion observed related to immune status and HIV-1 viral load.

AIDS-Related Opportunistic Infections↗
PubMed2001

Randomized clinical trial of primary treatment for temporomandibular joint disk displacement without reduction and without osseous changes: a combination of NSAIDs and mouth-opening exercise versus no treatment.

OBJECTIVE: The effectiveness of nonsteroidal anti-inflammatory drugs (NSAIDs) and physical therapy for disk displacement without reduction is unknown. This study compared this treatment method with nontreatment controls. METHODS: Sixty patients with painful disk displacement without reduction and without osseous changes were randomly divided in 2 groups, consisting of NSAID and physical therapy and a nontreated control group. Both groups were observed at 2 weeks and, for those patients who did not show any improvement, again at 4 weeks. RESULTS: There was 60% improvement in the treatment group compared with 33% in the control group during the entire 4 weeks of the study. The number needed to treat for benefit was 3.75, with a 95% CI 2.103 to 65.935. CONCLUSIONS: A combination of NSAID and physical therapy for 4 weeks is effective as a primary treatment of patients with disk displacement without reduction and without osseous changes.

Adolescent↗
PubMed2001

Comparison of clinical outcome of periapical surgery in endodontic and oral surgery units of a teaching dental hospital: a retrospective study.

OBJECTIVES: The aims of this retrospective study were (1) to compare the outcome of periapical surgery performed in endodontic and in oral surgery units of a teaching dental hospital and (2) to evaluate the influence of factors affecting outcome. STUDY DESIGN: A total of 176 teeth (endodontic unit, 83; oral surgery unit, 93) surgically treated more than 4 years previously were examined clinically and radiographically by means of strict criteria. Multiple logistic regression analysis was used. RESULTS: The rate of complete healing for patients treated in the endodontic unit (37.4%) was significantly (P = .009) higher than that for patients treated in the oral surgery unit (19.4%). The technical quality of surgery (P < .001), placement of root-end filling (P = .039), absence of a preoperative periapical lesion (P = .042), absence of a post (P = .047), and presence of an adequate coronal restoration (P = .056, odds ratio = 3.71) had significant effects on treatment outcome. CONCLUSION: The technical quality of periapical surgery, the presence of a periapical lesion, and adequate apical and coronal seal are important prognostic determinants of successful periapical surgery.

Adult↗
PubMed2001

Estimation of skeletal bone mineral density by means of the trabecular pattern of the alveolar bone, its interdental thickness, and the bone mass of the mandible.

OBJECTIVE: We sought to evaluate the use of the alveolar trabecular pattern, the mandibular alveolar bone mass (MABM) measured by photodensitometry, and the interdental alveolar thickness for prediction of the skeletal bone mineral density (BMD). STUDY DESIGN: MABM and the coarseness of trabeculation were assessed by using periapical radiographs in 80 dentate women. The interdental alveolar thickness was measured on casts, and BMD of the forearm with dual X-ray absorptiometry. RESULTS: Significant correlations were found between skeletal BMD and MABM (r = 0.46, P <.001) as well as the coarseness of the trabeculation (r = 0.62, P <.001). The interdental alveolar thickness improved the correlation between skeletal BMD and MABM (R2 = 0.44, P <.001). Age, but not interdental thickness, improved the correlation between the coarseness of trabeculation and skeletal BMD (R2 = 0.52, P <.001). CONCLUSION: Evaluation of the coarseness of trabeculation of the alveolar bone as seen on intraoral radiographs is a helpful clinical indicator of skeletal BMD and better than densitometric measurements of the alveolar bone. Dense trabeculation is a strong indicator of high BMD, whereas sparse trabeculation may be used to predict low BMD.

Absorptiometry, Photon↗
PubMed2002

Oral manifestations of patients with Marfan syndrome: a case-control study.

OBJECTIVE: The purpose of this study was to conduct a complete analysis of the oral abnormalities of patients with Marfan syndrome. STUDY DESIGN: Twenty three patients with Marfan syndrome and 69 healthy controls were studied. The subjects were screened for cariologic and periodontal alterations, as well as structural defects of enamel and dentin. Data analysis was performed by using the t test, the chi-square test, and regression models. RESULTS: Patients aged 0 to 17 years were significantly at risk for caries. Local hypoplastic enamel spots were more frequent in Marfan syndrome and could be related to caries history of the deciduous dentition. Root deformity, abnormal pulp shape, and pulpal inclusions were a frequent finding in patients with Marfan syndrome. Calculus and gingival indices were significantly higher in the study group as well. CONCLUSIONS: This study shows the importance of early diagnosis of oral anomalies and timely treatment of dental problems in Marfan syndrome. A series of therapeutic guidelines to be integrated in treatment strategies is proposed.

Adolescent↗
PubMed2002

Oral fungal colonization and oral candidiasis in renal transplant patients: the relationship to Miswak use.

OBJECTIVES: The aim of this study was to determine and compare the prevalence of oral candidal colonization and oral candidiasis in a group of medically stable renal transplant patients (RTPs) and age and sex-matched healthy control (HC) subjects. STUDY DESIGN: The oral cavities of 58 RTPs and 52 HC subjects were clinically examined for the presence of oral candidiasis. Oral fungal colonization was determined by using the concentrated oral rinse technique. RESULTS: Prevalence of oral fungal colonization was not significantly higher in RTPs than in HC subjects (74.1% vs 59.6%, respectively; P =.1), but the density of growth was significantly higher in RTPs (P <.0017). Oral candidiasis was diagnosed in 15.5% of RTPs but in none of HC subjects (P =.002). RTPs who used a chewing stick (Miswak: Salvadora persica ) for oral hygiene had a significantly lower prevalence of oral candidiasis (P =.04) compared with other RTPs. CONCLUSIONS: RTPs are at high risk of developing oral candidiasis. More clinical investigations are needed to determine the antimycotic effect of Miswak. Regular oral screening is recommended for RTPs.

Adolescent↗
PubMed2002

Routine panoramic radiography of new adult patients in general dental practice: relevance of diagnostic yield to treatment and identification of radiographic selection criteria.

OBJECTIVES: We sought to measure the diagnostic yield of relevance to treatment on routine panoramic radiographs taken of new adult (ie, 18 years and over) patients in general dental practice. STUDY DESIGN: Routine panoramic radiographs (n = 1817) obtained from general dental practice were assessed and radiologic yield recorded using consensus viewing by 2 dental radiologists. A modified diagnostic yield of relevance to treatment for each radiograph was calculated by omission of findings that would have been identified on bilateral posterior bitewing radiographs and of radiologic findings of no relevance to treatment. Stepwise logistic regression analysis was used in attempt to identify clinical indicators of a high diagnostic yield of relevance to treatment. RESULTS: The diagnostic yield of relevance to treatment was zero for the majority (56%) of patients. This figure rose to 71% when the symptom-free patients were considered. Five clinical indicators for panoramic radiography were identified, as follows: clinical suspicion of teeth with periapical pathologic conditions, presence of partially erupted teeth, clinically evident caries lesions, swelling, and clinically suspected unerupted teeth. CONCLUSION: Routine panoramic radiography of adult dental patients is not supported by the results of this study. The use of clinical indicators to select patients may help to improve diagnostic yield.

Adult↗
PubMed2002

Salivary albumin and other constituents and their relation to oral and general health in the elderly.

OBJECTIVE: Our objective was to study salivary albumin concentrations in the elderly. We expected higher albumin values in the frail and diseased elderly in comparison to the more fit elderly. This was thought to be due to the eventually decreased mucosal integrity in the diseased patients. STUDY DESIGN: Paraffin wax-stimulated saliva was collected for 5 minutes from 131 hospitalized elderly, mean age of 82 years, and 252 elderly outpatients, mean age of 77 years. Forty-seven of the hospitalized elderly died during the 2-year follow-up. Albumin was analyzed spectrophotometrically from the saliva specimens, and values were studied statistically between the groups and regarding a number of background variables. RESULTS: The following mean salivary albumin concentrations were observed: outpatients, 200 +/- 157 microg/mL; hospitalized surviving patients, 401 +/- 247 microg/mL; patients who later died, 501 +/- 417 microg/mL. The respective albumin output values were 439.7 +/- 432.8 microg/min in outpatients, 684.3 +/- 396.8 microg/min in hospitalized patients who survived, and 700.0 +/- 481.9 microg/min in the hospitalized patients who died. The differences were significant between the groups. The strongest explanatory factors for higher than median albumin concentrations were the use of analgesics in the hospitalized patients (odds ratio, 4.2; confidence interval, 1.5 to 11.4) and retaining own teeth in the outpatients (odds ratio, 4.3; confidence interval, 1.9 to 4.3). Frequency of mucosal pathologic condition did not appear as an explanatory factor in this respect. CONCLUSIONS: Our study hypothesis was confirmed, showing significantly higher salivary albumin concentrations in the frail elderly. The present results may also be used as reference data for salivary albumin in the elderly.

Aged↗
PubMed2002

Effect of professional oral health care on the elderly living in nursing homes.

OBJECTIVE: We evaluated the effectiveness of professional oral health care (POHC) given by dental hygienists once a week for 24 months to 141 elderly persons needing daily care and living in 2 nursing homes. STUDY DESIGN: Elderly subjects with POHC and without POHC living in 2 nursing homes were examined for 24 months to detect any fevers of 37.8 degrees C or more and the prevalence of fatal aspiration pneumonia. The numbers of Staphylococcus species and Candida albicans in swab samples from oral cavities were compared between the POHC group and the non-POHC group. The amounts of methylmercaptan exhaled in the POHC group were determined and compared with those in the non-POHC group. RESULTS: The prevalence of fevers of 37.8 degrees C or more in the subjects receiving POHC was significantly lower than in the non-POHC group (P < .05). We found that the ratio of fatal aspiration pneumonia in the POHC group during the 24 months was significantly lower than in the non-POHC group (P < .05). Numbers of C albicans species in samples obtained from the oral cavity after 6 months of POHC were significantly lower than those in the non-POHC group (P < .01). POHC resulted in the reduction of the presence of Staphylococcus but not to a statistically significant extent. The amounts of methylmercaptan exhaled by the POHC group were significantly less than those of the non-POHC group (P <.05). CONCLUSION: This study showed that POHC administered by dental hygienists to a group of elderly patients needing daily nursing care was associated with a reduction in prevalence of fever and fatal pneumonia.

Aged↗
PubMed2002

Mandibular, sagittal split osteotomies fixed with biodegradable or titanium screws: a prospective, comparative study of postoperative stability.

OBJECTIVE: Comparison of skeletal stability following bilateral sagittal split osteotomy (BSSO) advancement of the mandible fixed with titanium or biodegradable bicortical screws. STUDY DESIGN: Forty consecutive patients underwent mandibular advancement by means of BSSO performed with a standardized technique. In 20 patients rigid fixation was achieved by means of titanium bicortical screws; the other 20 patients were fixed with biodegradable copolymer screws made of poly-L-lactic acid (82%) and polyglycolic acid (18%). Lateral cephalograms were obtained 1 week preoperatively, 1 week postoperatively and after a minimum of 6 months postoperatively. Relevant skeletal points were traced and digitized to evaluate 2-dimensional skeletal change. Changes at each time point were analyzed and compared statistically. RESULTS: There was no statistically significant difference in long-term stability between the 2 groups. No clinical or radiographic evidence of wound healing problems were noted. CONCLUSION: Resorbable poly-L-lactic/polyglycolic acid copolymer bicortical screw fixation of a BSSO is a viable alternative to titanium screws for the fixation of advancement BSSO.

Absorbable Implants↗
PubMed2001

A comparison of the wear resistance and hardness of indirect composite resins.

STATEMENT OF PROBLEM: Various new, second-generation indirect composites have been developed with claimed advantages over existing tooth-colored restorative materials. To date, little independent research has been published on these materials, and the properties specified in the advertising materials are largely derived from in-house or contracted testing. PURPOSE: Four second-generation indirect composites (Artglass, belleGlass, Sculpture, and Targis) were tested for wear resistance and hardness against 2 control materials with well-documented clinical application. Human enamel was also tested for comparison. MATERIAL AND METHODS: Twelve specimens of each material were fabricated according to the manufacturers' directions and subjected to accelerated wear in a 3-body abrasion, toothbrushing apparatus. Vickers hardness was measured for each of the tested materials, and energy dispersive x-ray (EDX) spectroscopy was performed to determine the elemental composition of the composite fillers. The statistical tests used for wear and hardness were the Kruskal-Wallis 1-way ANOVA test with Mann-Whitney tests and 1-way ANOVA with multiple comparisons (Tukey HSD). The Pearson correlation coefficient was used to determine the existence of a relationship between the hardness of the materials and the degree to which they had worn. The level of statistical significance chosen was alpha=.05. RESULTS: The control material Concept was superior to the other composites in wear resistance and hardness and had the lowest surface roughness. Significant relationships were observed between depth of wear and hardness and between depth of wear and average surface roughness. Enamel specimens were harder and more wear resistant than any of the composites. EDX spectroscopy revealed that the elemental composition of the fillers of the 4 new composites was almost identical, as was the composition of the 2 control composites. CONCLUSION: The differences in wear, hardness, and average surface roughness may have been due to differences in the chemistry or method of polymerization of the composites. Further research in this area should be encouraged. It was also apparent that the filler present in the tested composites did not exactly fit the manufacturers' descriptions.

Acrylic Resins↗