Suun ulkopuolisella täytteellä tarkoitettaan täytteitä, jotka valmistetaan hammaslaboratoriossa hammasteknikon toimesta tai vastaanotolla CAD/CAM (computer-aided design and computer-aided manufacturing) menetelmällä (chair-side). CAD/CAM menetelmässä preparoitu hammas kuvannetaan digitaalisesti, jonka jälkeen muodostuneen kuvan avulla suunnitellaan halutun muotoinen täyte, joka jyrsitään tietokoneohjatusti keraamisesta blokista. Keraamiset materiaalit voidaan jakaa neljään ryhmään: maasälpäpohjaisiin (posliini), lasikeraameihin (leusiitti- ja litiumdisilikaatti vahvisteiset), ydinvahvisteisiin (alumiinioksidi- ja zirkonia pohjaiset) sekä yhdistelmä keraameihin (lasikeramia+zirkonia). Hammaslaboratoriossa voidaan valmistaa valamalla myös kultatäytteitä. Suun ulkopuolisten täytteiden preparoinnissa molaarien ja premolaarien pienten kaviteettien suositeltu preparointitapa on approksimaali- ja okklusaalipinnan kattava avaus (mesiaalinen — okklusaalinen — distaalinen täyte, MOD). MOD-inlayn valmistaminen molaareihin on hyväksyttävää, jos preparoinnit kyetään pitämään kapeina, sillä mitä laajempi on isthumksen preparointi bukkolinguaali suunnassa, sitä suuremmaksi inlay-täytteen kohdistama paine kuspeihin kasvaa ja sitä todennäköisemmin kuspit voivat lohjeta. Preparoinnin syvyyden vaikutus on myös huomioitava preparointia tehdessä, sillä syvyyden kasvaessa myös kuspin mekaaninen korkeus kasvaa, tarkoittaen sitä, että kuspin momenttivarsi ja voiman momentti kasvavat, joka altistaa kuspin mekaaniselle stressille. Premolaareihin tehtävät MOD-inlayt ovat kyseenalaisia ja premolaareissa tulisikin suosia MOD-onlay-täytteitä. Onlay-täyte jakaa hampaaseen kohdistuvan purentapaineen laajemmalle alueelle, jolloin inlay-täytteiden aiheuttamaa kiilaefektiä ei pääse syntymään. Onlay-täytteitä tulisi käyttää myös tilanteissa, joissa MOD-preparoinnin isthmus on laaja tai juurihoidetuissa takahampaissa, joissa on hyväkuntoiset hammasseinämät. Tutkimuksen tarkoituksena oli verrata CAD/CAM-tekniikalla (CEREC laitteella) tehtyjen keraamisten inlay- ja onlay-täytteiden preparointeja preparointiohjeisiin. Materiaalina tutkimuksessa käytettiin Oulun kaupungin opetushammashoitolassa tehtyjä litiumdisikaattivahvisteisia lasikeramia (IPS e.max®, Ivoclar Vivadent) inlay- ja onlaytäytteitä varten hiottuja kaviteetteja sekä tehtyjä täytteitä. Kaviteettien skannaukset tehtiin Cerec AC (Dentsply Sirona) -laitteistolla ja suunnittelu inLab SW 15.1 (Dentsply Sirona) laboratoriokäyttöön tarkoitetulla suunnitteluohjelmalla. Tutkimukseen valikoitiin satunnaisesti seitsemän (7) ensimmäiseen molaariin tehtyä kaviteettia ja täytettä. Tutkimuksen kaviteettien ja täytteiden mittaukset suoritettiin InLab SW 15.1 -ohjelmistossa olevilla mittaustyökaluilla. Kavieeteista määritettiin minimi ja maximi arvoja kaviteettien morfologista muodoista sekä tehdyn paikan paksuuksista Tutkimus osuuden löydöksinä olivat: linguaali/palatinaalisten seinämien paksuuden arvot olivat suurempia bukkaalisiin seinämiin verrattuna. Keskimäärin paikkojen okklusaalisen(kuspi ja fissuura) paksuuden arvot olivat riittäviä materiaalien vaatiman paksuuden osalta.

INTRODUCTION: Cast analysis plays an essential role in orthodontic diagnosis. Intraoral scanning to produce digital models is a relatively new but increasingly common practice in graduate orthodontic programs. It is unknown how incorporating digital models in post graduate orthodontic programs will influence student learning of model analysis. The purpose of this study was to investigate the possible differences in learning speed and accuracy of basic orthodontic model analysis using digital models or traditional plaster casts. MATERIALS/METHODS: Two groups of senior dental students participated, one for each mode of cast analysis. A study moderator provided a 15-minute tutorial instructing participants on how to analyze the casts. A standardized scoring sheet was used for data collection. Each group was given five sets of orthodontic models to measure the following parameters: Right molar occlusion, overbite, overjet, arch length, required arch space, crowding, and incisor irregularity. The accuracy of the measurements as well as the time taken to complete all measurements on each model were recorded. Learning as measured by increasing accuracy or decreased time over the group of five casts was determined. Five orthodontic faculty served as the control group. RESULTS: Twenty-five students analyzed plaster casts; forty students analyzed digital casts. Molar occlusion was judged as either correct or incorrect; means of the millimetric measurements of the other parameters were compared between groups using general linear modeling. The digital learning group had 15 measurements that were significantly different from the faculty mean; the plaster learning group had only 2 (p<0.05). Regarding molar occlusion, the plaster group was always more accurate. The time required for the measurements decreased in each group to a similar extent, with the greatest decrease between digital casts 1 and 2. CONCLUSIONS: Senior dental students learned how to analyze plaster orthodontic models more accurately than digital casts. The time required for analysis decreased over 5 trials, but was not significantly different between the groups.

The tobacco cigarette industry is a multi-billion dollar industry that has continued to thrive at the expense of its consumer’s health. Through the use of their provocative, and often exaggerated advertising campaigns they have successfully been able to lure a great amount of customers, and have been able to retain most of them for years due to their products addictive nature. Unfortunately, many of their clientele are children as young as 13 years old. Their products have first started to appeal to these individuals when tobacco companies were allowed to use cartoon characters to represent their brands. It wasn’t until a ban forbidding tobacco companies to use cartoon characters or lovable-looking dromedary in cool clothes became effective in 1998, can a decrease of smoking in that age group be observed. Others in that age group and well into adult years were found to have initiated tobacco smoking for peer and self-validation purposes. This study was designed to analyze the attitudes of young adults towards tobacco smoking, and determine how knowledgeable they were about tooth loss and its associated health risks. Through the use of a questionnaire comprised of 19 questions and completed by young adults between the ages of 18 and 23, data was able to be collected and analyzed in order to form conclusions to answer some of these determinations. The data collected was analyzed by running some statistical tests with different variable combinations. In addition, tables and graphs were generated in order to have a clear illustrative image of what the data is meant to represent. Unfortunately, the data was found to be statistically insignificant except when examining tobacco smoking attitudes and knowledge against sex and race. Women were found to be more knowledgeable of the impacts that tobacco has on tooth loss and Asians/Hawaiians and Blacks were found to be less likely to strongly agree and/or more likely to disagree that smoking causes disease compared to other ethnic groups. Black participants were also found to less likely strongly agree and/or more likely to disagree that healthy smile equals a healthy body, and that missing teeth affect self-image.

OBJECTIVES: To evaluate the effect of sintering time and temperature on the optical property, grain size, and mechanical property of various translucent zirconias. The specific aims are to compare the contrast ratio, grain size, and biaxial flexural strength of four different monolithic translucent zirconia materials using different coloring liquids. MATERIALS AND METHODS: For the test of the effect of sintering parameters on translucent zirconia materials, commercial TOSOH Y-TZP powders, Zpex and Zpex Smile were uniaxial dry-pressed in a mold, yielding 1.3 mm thickness discs. They were presintered using either a short or a long duration and then sintered at different final temperatures (1300 °C, 1450 °C, 1600 °C). Biaxial flexural strength was measured using an Instron Universal Testing machine. Contrast ratio was measured with a spectrophotometer. Grain size was measured on scanning electron microscopic (SEM) micrographs using ImageJ software. For the test of the effect of coloring liquids on contrast ratio, four different monolithic translucent zirconia blocks were sectioned into 1.3 mm thickness tiles. Coloring liquids of two shades (A2, D3) for each corresponding brand and Tanaka Zircolor dipping liquids were used for coloring the zirconia. For the same brand coloring liquid, Bruxzir HT was colored by BruxZir Coloring Liquid, Crystal Diamond Zirconia by Crystal color, Zenostar Zr translucent by Zenostar color Zr, and Zirkonzhan translucent by Zirkonzahn prettau aquarelle. A spectrophotometer was used to measure contrast ratio. For the test of the effect of coloring liquids on flexural strength, four different monolithic translucent zirconia milling blocks were sectioned into bars 1.5mm x 2 mm x15 mm, and colored into shade A2 with their manufacturers coloring liquid and Tanaka Zircolor liquid. A three-point bend test was performed using an Instron machine. Data was analyzed by JMP Pro 13 using multifactorial linear regression and ANOVA post hoc Tukey HSD test. The effects of difference factors and differences between groups were compared. The P-values less than 0.05 were considered statistically significant. RESULTS AND CONCLUSIONS: The contrast ratio and biaxial flexural strength of Zpex is significantly greater than Zpex Smile. There is a significant difference in contrast ratio and biaxial flexural strength between different presintering cycles and final sintering temperatures. The grain size of Zpex Smile discs was significantly greater than Zpex discs. The final sintering temperature, material and their interaction have significant effects on the grain size while there is no significant effect on the grain size by different presintering cycles. The contrast ratio of Bruxzir HT, Crystal diamond Zirconia and Zirkonzahn translucent is significantly greater than Zenostar Zr tanslucent. There is significant difference in contrast ratio with different shades and coloring liquid brands. The highest contrast ratio was seen when the material was colored with Tanaka shade D3. The flexural strength of Bruxzir HT and Crystal Diamond Zirconia was significantly greater than Zenostar Zr translucent and Zirkonzahn translucent. There was a significant difference in flexural strength between unaltered and colored Zirconia with Tanaka coloring liquid. The highest flexural strength was seen when the unaltered material was sintered.

Glass-ionomer cement has been used in the Atraumatic Restorative Technique (ART) for stabilisation of carious lesions. The infected layer or fully demineralised dentine is removed by dental hand instruments only and glass-ionomer cement is placed to restore the lesion leaving the affected layer or partly demineralised dentine underneath. There are many anecdotal and some published reports of the ability of these materials to remineralise partly demineralised dentine. The major objectives of this investigation are: 1. To scientifically demonstrate the ability of glass-ionomers to remineralise partly demineralised dentine in vivo and in vitro. 2. To determine the nature of the remineralisation process. 3. To determine those factors having greatest impact on the remineralisation process. Those objectives are partly met with the use of EPMA and an in vitro model, specially designed to simulate clinical conditions as closely as possible. With EPMA, it is possible to identify, quantify and trace the migration of different elements, found in glass-ionomer, into the partly demineralised dentine. The results lead to a better understanding of the possible mechanisms involved. There have been anecdotal and clinical reports on the remineralisation of carious dentine left at the base of glass-ionomer restorations. This was confirmed in a human in vivo study. The information derived from it was utilised in the design of an in vitro model to allow in depth study of the effects, on the remineralisation process, of the following two variables: 1. The level of remaining minerals in dentine 2. The length of contact with the glass-ionomer The results support the hypothesis that the close adaptation of glass-ionomer cement to demineralised dentine will lead to the uptake of apatite forming ions into dentine and lead to its remineralisation. The process involved first the diffusion then the precipitation of both strontium and fluorine from the glass ionomer into the partly demineralised dentine. This process is dependent on the glass-ionomer, the level of demineralisation of dentine and the time that it stays in contact with the glass-ionomer. The combination of Fuji VI with a treatment time of 42 days has the best potential for remineralisation. However, further study is required before the mechanism involved can be fully understood. / Thesis (Ph.D.)--Dental School, 2005.

Thesis (M.S.)--University of Michigan School of Dentistry, 1986. / Includes bibliographical references. Also issued in print.

Thesis (Ph. D.)--Oklahoma State University, 1996. / Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thèse--Lyon.

Thesis.

Thesis (Habilitation)--Ludwig-Maximilians-Universität München, 1976. / Includes bibliographical references.