Anthony M. Iacopino

An Update on Novel Non-Invasive Approaches for Periodontal Diagnosis

For decades there has been an ongoing search for clinically acceptable methods for the accurate, non-invasive diagnosis and prognosis of periodontitis. There are several well-known inherent drawbacks with current clinical procedures. The purpose of this review is to summarize some of the newly emerging diagnostic approaches, namely, infrared spectroscopy, optical coherence tomography (OCT), and ultrasound. The history and attractive features of these new approaches are briefly illustrated, and the interesting and significant inventions related to dental applications are discussed. The particularly attractive aspects for the dental community are that some of these methods are totally non-invasive, do not impose any discomforts to the patients during the procedure, and require no tissue to be extracted. For instance, multiple inflammatory indices withdrawn from near infrared spectra have the potential to identify early signs of inflammation leading to tissue breakdown. Morphologically, some other non-invasive imaging modalities, such as OCT and ultrasound, could be employed to accurately measure probing depths and assess the status of periodontal attachment, the front-line of disease progression. Given that these methods reflect a completely different assessment of periodontal inflammation, if clinically validated, these methods could either replace traditional clinical examinations for the diagnosis of periodontitis or at least serve as attractive complementary diagnostic tools. However, the potential of these techniques should be interpreted more cautiously given the multifactorial character of periodontal disease. In addition to these novel tools in the field of periodontal inflammatory diseases, other alternative modalities like microbiologic and genetic approaches are only briefly mentioned in this review because they have been thoroughly discussed in other comprehensive reviews.

Racial/Ethnic Disparities in the Acceptance of Medicaid Patients in Dental Practices

OBJECTIVES Medicaid enrollees disproportionately experience dental disease and difficulties accessing needed dental care. However, little has been documented on the factors associated with the acceptance of new Medicaid patients by dentists, and particularly whether minority dentists are more likely to accept new Medicaid patients. We therefore examined the factors associated with the acceptance of new Medicaid patients by dentists. METHODS We analyzed 2001 data from the Wisconsin Dentist Workforce Survey administered by the Wisconsin Division of Health Care Financing, Bureau of Health Information. We used descriptive statistics and logistic regression analysis to examine the factors associated with the outcome variable. RESULTS Ninety-four percent of Wisconsin licensed dentists (n = 4,301) responded to the 2001 survey. A significantly higher likelihood of accepting new Medicaid patients was found for racial/ethnic minority dentists (35 versus 19 percent of White dentists) and dentists practicing in large practices (31 versus 16 percent for those in smaller practices). In the multivariable analysis, minority dentists [odds ratio (OR) = 2.06, 95 percent confidence interval (CI) = 1.30, 3.25] and dentists in practices with >3 dentists (OR= 2.25, 95 percent CI = 1.69, 3.00) had significantly greater odds of accepting new Medicaid patients. CONCLUSIONS Racial/ethnic minority dentists are twice as likely as White dentists to accept new Medicaid patients. Dentists in larger practices also are significantly more likely than those in smaller practices to accept new Medicaid patients. These findings suggest that increasing dental workforce diversity to match the diversity of the general US population can potentially improve access to dental care for poor and minority Americans, and may serve as an important force in reducing disparities in dental care.

Mechanical Behavior and Failure Analysis of Prosthetic Retaining Screws after Long‐term Use in vivo. Part 4: Failure Analysis of 10 Fractured Retaining Screws Retrieved from Three Patients

PURPOSE The aim of this study was to perform a failure analysis on fractured prosthetic retaining screws after long-term use in vivo. Additionally, the study addresses the commonly asked question regarding whether complex repeated functional occlusal forces initiate fatigue-type cracks in prosthetic retaining screws. MATERIALS AND METHODS Ten fractured prosthetic retaining screws retrieved from three patients treated with fixed detachable hybrid prostheses were subjected to a failure analysis. In patients 1 and 2, the middle three retaining screws of the prostheses were found fractured at retrieval time after they had been in service for 20 and 19 months, respectively. In patient 3, the middle three and one of the posterior retaining screws were found to be fractured at retrieval after they had been in service for 18 months. Low power stereomicroscopy and high-power scanning electron microscopy (SEM) were performed to analyze the fractured surfaces of the retaining screws examining fatigue cracks in greater detail. RESULTS Typical fatigue failure characterized by ratchet mark formation was revealed by light microscopy and SEM for all examined screws. Using low magnification light microscopy, ratchet marks were visible on the fracture surfaces of only two screws. SEM examination revealed all three classical stages of fatigue failure, and it was possible to see the ratchet marks on the fracture surfaces of all specimens, indicating a fatigue zone. The final catastrophic overload fracture appeared fibrous, indicating ductile fracture. The final overload ductile fracture surfaces showed equiaxed dimples, suggesting tensile overload in all examined screws except in two specimens that showed an elongated dimple pattern indicating shear/tearing overload forces. CONCLUSIONS Fracture of prosthetic retaining screws in hybrid prostheses occurs mainly through a typical fatigue mode involving mostly the middle anterior three screws. Fatigue cracks can grow in more than one prosthetic retaining screw, leading to fracture before the patient or clinician determines that any problem exists.

Socio-demographics of adult orthodontic visits in the United States.

INTRODUCTION Population-based studies in orthodontics have focused on differences between normative and perceived needs. However, information from national data on the prevalence of orthodontic visits and their associated factors in adults in the United States is scarce. We examined the demographic profile of likely adult users of orthodontic services and whether there is racial and ethnic disparity in orthodontic visits. METHODS We analyzed data from the Medical Expenditure Panel Survey, 2000-2004. RESULTS Overall, about 1% of the population reported an orthodontic visit. Subjects who made a general dental visit during the current year were significantly more likely to also have an orthodontic visit. Single adults, women, people between 18 and 30 years of age, and those from high-income families were more likely to report an orthodontic visit. There were no indications of racial and ethnic disparity for either black or Hispanic adults compared with white adults after adjusting for other covariates. CONCLUSIONS Substantial racial and ethnic disparity in adult orthodontic usage was not identified. Adults (ages 18-30 years), women, those with higher incomes, and single adults had significantly higher odds of reporting an orthodontic visit. However, additional studies specifically evaluating the association of treatment need among low-income families are required to evaluate whether these adults face significant barriers in accessing orthodontic care.

Mechanical Behavior and Failure Analysis of Prosthetic Retaining Screws after Long-term Use In Vivo. Part 3: Preload and Tensile Fracture Load Testing

PURPOSE The aim of this study was to determine the preload and tensile fracture load values of prosthetic retaining screws after long-term use in vivo compared to unused screws (controls). Additionally, the investigation addressed whether the preload and fracture load values of prosthetic retaining screws reported by the manufacturer become altered after long-term use in vivo. MATERIALS AND METHODS For preload testing, 10 new screws (controls) from Nobel Biocare (NB) and 73 used retaining screws [58 from NB and 15 from Sterngold (SG)] were subjected to preload testing. For tensile testing, eight controls from NB and 58 used retaining screws (46 from NB and 12 from SG) were subjected to tensile testing. Used screws for both tests were in service for 18-120 months. A custom load frame, load cell, and torque wrench setup were used for preload testing. All 83 prosthetic screws were torqued once to 10 Ncm, and the produced preload value was recorded (N) using an X-Y plotter. Tensile testing was performed on a universal testing machine and the resulting tensile fracture load value was recorded (N). Preload and tensile fracture load values were analyzed with 2-way ANOVA and Tukey post-hoc tests. RESULTS There was a significant difference between preload values for screws from NB and screws from SG (p < 0.001). The preload values for gold alloy screws from NB decreased as the number of years in service increased. There was a significant difference between tensile fracture values for the three groups (gold alloy screws from NB and SG and palladium alloy screws from NB) at p < 0.001. The tensile fracture values for gold alloy screws from NB and SG decreased as the number of years in service increased. CONCLUSIONS In fixed detachable hybrid prostheses, perhaps as a result of galling, the intended preload values of prosthetic retaining screws may decrease with increased in-service time. The reduction of the fracture load value may be related to the increase of in-service time; however, the actual determination of this relationship is not possible from this study alone.

25-year Analysis of a Dental Undergraduate Research Training Program (BSc Dent) at the University of Manitoba Faculty of Dentistry

Research in the context of the dental school has traditionally been focused on institutional/faculty accomplishments and generating new knowledge to benefit the profession. Only recently have significant efforts been made to expand the overall research programming into the formal dental curriculum, to provide students with a baseline exposure to the research and critical thinking processes, encourage evidence-based decision-making, and stimulate interest in academic/research careers. Various approaches to curriculum reform and the establishment of multiple levels of student research opportunities are now part of the educational fabric of many dental schools worldwide. Many of the preliminary reports regarding the success and vitality of these programs have used outcomes measures and metrics that emphasize cultural changes within institutions, student research productivity, and student career preferences after graduation. However, there have not been any reports from long-standing programs (a minimum of 25 years of cumulative data) that describe dental school graduates who have had the benefit of research/training experiences during their dental education. The University of Manitoba Faculty of Dentistry initiated a BSc Dent program in 1980 that awarded a formal degree for significant research experiences taking place within the laboratories of the Faculty-based researchers and has continued to develop and expand this program. The success of the program has been demonstrated by the continued and increasing demands for entry, the academic achievements of the graduates, and the numbers of graduates who have completed advanced education/training programs or returned to the Faculty as instructors. Analysis of our long-term data validates many recent hypotheses and short-term observations regarding the benefits of dental student research programs. This information may be useful in the design and implementation of dental student research programs at other dental schools.

Factors Associated With Receipt of Preventive Dental Treatment Procedures Among Adult Patients at a Dental Training School in Wisconsin, 2001-2002

BACKGROUND Gender differences in oral health-related quality of life and the fear of dental pain in seeking and receiving preventive dental care have been recognized and documented. Preventive dental treatment procedures (PDTPs) are commonly accepted as the primary approach to prevent dental disease. OBJECTIVE We examined whether the likelihood of receiving PDTPs differed by gender in adult patients receiving dental care at a dental training institution in Milwaukee, Wisconsin. METHODS Data from the Marquette University School of Dentistry electronic patient management database for 2001 through 2002 were analyzed. Descriptive, bivariate, and multivariable analyses were performed. The preventive procedures used in the study were those coded in accordance with the American Dental Associations classification system: D1110 (adult prophylaxis: professional cleaning and polishing of the teeth), D1204 (adult topical application of fluoride), D1205 (adult topical application of fluoride plus prophylaxis), and D1330 (oral hygiene instruction). RESULTS Of the 1563 consecutive patient records (888 women, 675 men) reviewed for the years 2001-2002, 794 individuals (51%), aged 18 to 60 years, were identified as having received PDTPs. At the bivariate level, a significant gender difference in the receipt of PDTPs was identified (423 women [48%] vs 371 men [55%]; P = 0.004). In the multivariable analyses, age, race/ethnicity, marital status, poverty level, and health insurance type (public, private, none) were significantly associated with the receipt of PDTPs (all, P < 0.05), but gender was not. CONCLUSIONS Gender differences in receiving PDTPs were not found in this dental school patient population. Receipt of PDTPs was associated with other demographic factors such as age, race/ethnicity, marital status, income level, and health insurance.

The effect of FIV infection on CD4+ and CD8+ counts in periradicular lesions

AIM The purpose of this study was to elucidate whether a decrease/increase in T-cell populations is present in the development of periradicular disease in the immunocompromised feline model. METHODOLOGY Eight cats were immunosuppressed with steroids prior to infection with feline immunodeficiency virus (FIV). Another eight cats, age and sex matched littermates, were monitored and tested at equivalent periods of time and served as uninoculated, seronegative controls. Periradicular lesions were induced using local bacterial inoculations into the pulp of the canine teeth and assessed after one- and four-week periods, corresponding to the acute and chronic stages of the periradicular disease. Block sections were obtained and specimens were prepared for H & E and immunohistochemical staining for CD4+ and CD8+ receptors. Cells were quantified using a computer imaging system and data analysed using generalized estimating equation (GEE) regression models. RESULTS Significantly lower CD4+ counts and CD4+/ CD8+ ratios were observed at all time periods in the periradicular region of the FIV group (P = 0.0006). No significant difference in CD8+ counts was observed between the two groups. In both groups there was a significant difference in the CD4+ counts between one week and baseline, and 1 week and 4 weeks. There was no significant difference between baseline and 4 weeks for either group. CONCLUSION FIV infection reflected decreased CD4+ counts at the periradicular level, however, inflammation and progression of the lesion, appeared to be comparable to the non-immunocompromised controls.

Interleukin-1β Production in Periradicular Lesions in a Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome Model Compared with a Noninfected Host

This study elucidates the role of interleukin-1 (IL-1) in developing periradicular lesions in immunocompetent and immunocompromised (human immunodeficiency virus/acquired immune deficiency syndrome) hosts. Eight cats were immunosuppressed with steroids before infection with feline immunodeficiency virus (FIV). Eight uninoculated cats served as controls. Periradicular lesions were induced around the canine teeth. At 1 and 4 wk periradicular exudate was sampled via the root canals. IL-1beta levels were measured with ELISA. Data were analyzed using the Mann-Whitney U test and the Wilcoxon signed rank test. Statistically significant differences existed in cytokine levels between the FIV and non-FIV groups (p < 0.001). Cytokines were below detectable levels in the FIV group. A significant decrease in IL-1beta levels at 4 wk compared with 1 wk occurred in the non-FIV group (p < 0.05). In conclusion decreased IL-1beta production was obtained in the FIV group. In the non-FIV group decreases in IL-1beta levels were encountered at the chronic stage of the periradicular lesion compared with the acute stage.

An indirect technique for assuring simplicity and marginal integrity of provisional restorations during full mouth rehabilitation.

Full mouth rehabilitation with fixed prosthodontics can be a time- and labor-intensive process. The use of provisional restorations allows the treating clinician to determine the functional and esthetic requirements of the definitive prostheses. However, in the case of full mouth rehabilitation, the individual preparation of provisional restorations for multiple teeth may complicate the provisional phase and increase the treatment time. This article describes a method to simplify the indirect fabrication of provisional restorations for full mouth reconstruction. Provisional restorations may be easily achieved by splinting the provisional restorations in sextants, trimming them according to red pencil marks around the prepared margins as guidelines, and fitting them in the laboratory, utilizing a second set of solid casts for the prepared teeth.