Is the shortened dental arch an underused treatment strategy in the Republic of Ireland?

OBJECTIVES: To determine the proportion of Republic of Ireland 35-44 and 65+ year-olds currently satisfying the criteria for a classic shortened dental arch (SDA) of 20 anterior teeth.

RESEARCH DESIGN: Secondary analysis of data collected in the 2000/02 epidemiological survey of the oral health of Irish adults.

CLINICAL SETTING: Participants underwent a clinical oral examination in health board dental clinics and completed a detailed interview pertaining to dental and general health.

PARTICIPANTS: The analysis is based on a random sample of adults, aged 35 to 44 years (n = 978), and 65 years and older (n = 714).

MAIN OUTCOME MEASURES: The SDA was measured as 20 teeth in the mouth in the positions normally described as from the left second premolar to the right second premolar in each arch.

RESULTS: Only one of the 35-44 year-olds and none of the 65+ year-olds had teeth in their mouths in positions normally described as a classic SDA. However, of the 35-44 year old age group only five patients who had at least a premolar dentition of 20 contiguous teeth had been provided with a removable denture compared to one patient from the 65+ years group.

CONCLUSIONS: Very few older patients in the Republic of Ireland have a SDA based on the measure used. However, very few have been provided with removable dentures where they already possess at least a premolar dentition of 20 contiguous teeth. Suggested reasons for this may include limitations of the data recorded, patient preferences and economic factors.

Impact of tooth replacement strategies on the nutritional status of partially-dentate elders

OBJECTIVE: To investigate the impact of tooth replacement on the nutritional status of partially dentate older patients, and, to compare two different tooth replacement strategies; conventional treatment using removable partial dentures and functionally orientated treatment based on the shortened dental arch.

BACKGROUND: Amongst older patients, diet plays a key role in disease prevention, as poor diets have been linked to numerous illnesses. Poor oral health and loss of teeth can have very significant negative effects on dietary intake and nutritional status for elderly patients. There is evidence that good oral health generally, has positive effects on the nutritional intake of older adults.

MATERIALS AND METHODS: A randomised, controlled clinical trial was designed to investigate the impact of tooth replacement on the nutritional status of partially dentate elders. Forty-four patients aged over 65 years completed the trial, with 21 allocated to conventional treatment and 23 allocated to functionally orientated treatment. Nutritional status was accessed at baseline and after treatment using the Mini Nutritional Assessment (MNA) and a range of haematological markers.

RESULTS: At baseline, relationships were observed between the number of occluding tooth contacts and some measures of nutritional status. As the number of contacts increased, MNA scores (R = 0.16), in addition to vitamin B12 (R = 0.21), serum folate (R = 0.32) and total lymphocyte count (R = 0.35), also increased. After treatment intervention, the only measure of nutritional status that showed a statistically significant improvement for both treatment groups was MNA score (p = 0.03). No significant between group differences were observed from analysis of the haematological data.

CONCLUSION: In this study, prosthodontic rehabilitation with both conventional treatment and functionally orientated treatment resulted in an improvement in MNA score. Haematological markers did not illustrate a clear picture of improvement in nutritional status for either treatment group.

Prosthodontic care for elderly patients

For older patients, clinicians should consider maintaining teeth and using functionally-orientated treatment strategies as an alternative to removable prostheses. When the remaining dentition has a poor prognosis, key teeth should be preserved as overdenture abutments and a gradual transition to edentulousness planned. Where complete dentures are provided, these can be retained using dental implants to overcome many of the problems associated with conventional replacement dentures.

CLINICAL RELEVANCE: The elderly population of today is better informed and more demanding of oral healthcare providers than previous generations. Clinicians should be aware of all the prosthodontic treatment options available for older patients.

Toothwear and the older patient

Toothwear is commonly observed in dentate older patients and may be physiological or pathological in nature. Toothwear can be caused by abrasion, attrition, erosion or a combination of aetiologies. Where treatment is required, a number of options exist, including the use of adhesive materials and fixed and removable prosthodontics.

CLINICAL RELEVANCE: With patients retaining natural teeth into old age, physiological and pathological toothwear amongst dentate older patients is an increasingly common presentation.

Forças de mordida relacionadas a próteses parciais removíveis inferiores

A pesquisa teve como objetivo determinar as forças de mordida de 73 indivíduos, por meio de um gnatodinamômetro. Os pacientes eram portadores de próteses parciais removíveis inferiores classes I, II ou III. A arcada antagonista era prótese, parcial removível ou fixa, ou total. Os resultados permitiram concluir que: as selas de extremidade livre, principalmente em suas posições extremas, conduziram a forças de mordida muito baixas; o envolvimento de prótese total, também, conduziu a forças de mordida baixas; o sexo masculino alcançou valores maiores que o feminino; com prótese parcial removível classe III, os dentes naturais molares e pré-molares desenvolveram valores maiores do que com classes I e II.

Resinas para facetas estéticas de próteses fixas. III. Análise conjunta das variáveis alteração dimensional e alteração de peso em função de materiais, condição de armazenamento e tempos.

The authors analysed the simultaneous effects of the dimensional and weight alteration of resins utilized for esthetic facets submitted to warehousing conditions and periods of time. The resins showed different behaviour and a neat correlation between dimensional alteration and weight. The condition of immersion promoted dimensional alteration 50% lower and an alteration of weight three times higher.

Estudo comaprativo da resistência da união esmalt/resina/metal. Efeito de resinas de fixação, artifícios retentivos e ligas metálicas.

The purpose of this study was to compare the enamel/resin/metal bond tensile strength by using human canines, in which castings were bonded. These castings were obtained by Co-Cr or Ni-Cr alloys and showed four types of mechanisms of retention: 50 micrograms aluminum oxide abrasive, electrochemical etch, acrylic beads metal mesh. The castings were bonded utilizing Comspan Opaque and Panavia Ex. The specimens were subjected to tensile forces after 24 hours in an Instron machine. The castings subjected to 50 micrograms aluminum oxide abrasive and bonded utilizing Panavia EX showed the biggest bond tensile strength.

Fadiga de grampos de retenção em prótese parcial removível. Efeito de ligas, espessuras e técnicas de fusão. Parte I.

The authors looked for the verification of the fatigue of retentive clasps utilized on the removable partial denture. According to this, it was idealized and built on assay machine, that through movements, simulate the insertion and removal of the clasp for a pattern tooth, manufactured on cobalt-chromium which has all the preparation normally utilized to the correct confection of this type of prosthesis. It was utilized three different commercial alloys based on cobalt-chromium: L1-Biosil; L2-Steldent; L3-Duracron. It was utilized the T clasp of Roach, with was tested upon three different proportions among width and thickness: E1-1.7;E2-2.0 and E3-2.3 and was casted through two casting techniques: F1-oxygen-gas and F2-oxygen-acetylene. The clasps were tested on the machine, which allowed the reading of the number of insertion and removal cycles made until fatigue appeared. The obtained results were submitted to the statistic analysis and the authors concluded that: a) L3 (Duracrom) obtained the best results followed by L1 (Biosil) and finally L3 (Steldent); b) among the analyzed thickness, the best results were obtained by E3, followed by E2 and after this E1; c) form the casting techniques, F2 gave us the best results.

Shear bond strength fatigue limit of rest seats made with dental restoratives

Purpose: This study compared the shear bond strength (SBS) to enamel of rest seats made with a glass-ionomer cement (Fuji IX GP Fast), a resin-modified glass-ionomer cement (Fuji II LC), and a composite resin (Z100 MP) under monotonic and cyclic loading. Materials and Methods: Rest seats were built up onto the lingual surfaces of 80 intact human mandibular incisors. Specimens (n=10) were stored in distilled water at 37°C for 30 days and subjected to shear forces in a universal testing machine (0.5 mm/min) until fracture. The SBS values were calculated (MPa) using the bonding area (9.62 mm2) delimited by adhesive tags. A staircase approach was used to determine the SBS fatigue limit of each material. Specimens were submitted to either 10,000 cycles (5 Hz) or until specimen fracture. A minimum of 15 specimens was tested for each material. Scanning electron microscopy was used to examine the mode of failure. Data were statistically analyzed with one-way ANOVA and Tukey HSD tests (α = 0.05). Results: Z100 MP yielded higher (p < 0.05) SBS (12.25 MPa) than Fuji IX GP Fast (7.21 MPa). No differences were found between Fuji II LC (10.29 MPa) and the other two materials (p > 0.05). Fuji II LC (6.54 MPa) and Z100 MP (6.26 MPa) had a similar SBS limit. Fuji IX GP Fast promoted the lowest (p < 0.05) SBS fatigue limit (2.33 MPa). All samples showed cohesive failure patterns. Conclusion: Fatigue testing can provide a better means of estimating the performance of rest seats made with dental restoratives.

SEM analysis of the in situ early bacterial colonization on two novel feldspathic ceramics submitted to different types of glazing

Aim: The aim of this study was to evaluate in situ, the early bacterial colonization on feldspar-ceramics submitted to different glazing. Methods and Materials: Fourteen standardized disc specimens (diameter: 5 mm, thickness: 1.5 mm) of each of two micro-particulate feldspathic ceramics (VM7 and VM13, Vita) were produced according to manufacturers' specifications for a total of 28 specimens (24 for the analysis of biofilm and 4 for topographic analysis analyzing the ceramic surfaces). Specimens from each type of ceramic were submitted to two different glazing methods composing four groups: VM7 glazed using glazing liquid Vita Akzent® 25 (G1) and glaze firing (G2), VM13 glazed using glazing liquid (G3) and glaze firing (G4). Six individuals (n=6) wore oral appliances with four ceramic specimens, fixed on the buccal face of the appliances. After 8 hours, each sample was evaluated for the presence (1) or absence (0) of bacterial colonization under a scanning electron microscope (SEM) on five randomly selected fields. The value for each sample was cumulative of the results observed in the fields. One sample from each group was evaluated under a SEM to verify the topographic pattern. Results: There was no difference with regard to bacterial colonization between the feldspar-ceramics and between the glazing types (Kruskal-Wallis non-parametric test). Conclusion: Feldspar-ceramics submitted to firing or glaze firing with Vita Akzent® 25 present a similar condition for in situ bacterial colonization. The similar topographic pattern of the ceramic surfaces seems to have influenced the bacterial colonization.

Influence of thermal and mechanical cycling on the flexural strength of ceramics with titanium or gold alloy frameworks

Objectives: The aim of this study was to evaluate the effect of thermal and mechanical cycling alone or in combination, on the flexural strength of ceramic and metallic frameworks cast in gold alloy or titanium. Methods: Metallic frameworks (25 mm × 3 mm × 0.5 mm) (N = 96) cast in gold alloy or commercial pure titanium (Ti cp) were obtained using acrylic templates. They were airborne particle-abraded with 150 μm aluminum oxide at the central area of the frameworks (8 mm × 3 mm). Bonding agent and opaque were applied on the particle-abraded surfaces and the corresponding ceramic for each metal was fired onto them. The thickness of the ceramic layer was standardized by positioning the frameworks in a metallic template (height: 1 mm). The specimens from each ceramic-metal combination (N = 96, n = 12 per group) were randomly assigned into four experimental fatigue conditions, namely water storage at 37 °C for 24 h (control group), thermal cycling (3000 cycles, between 4 and 55 °C, dwell time: 10 s), mechanical cycling (20,000 cycles under 10 N load, immersion in distilled water at 37 °C) and, thermal and mechanical cycling. A flexural strength test was performed in a universal testing machine (crosshead speed: 1.5 mm/min). Data were statistically analyzed using two-way ANOVA and Tukey's test (α = 0.05). Results: The mean flexural strength values for the ceramic-gold alloy combination (55 ± 7.2 MPa) were significantly higher than those of the ceramic-Ti cp combination (32 ± 6.7 MPa) regardless of the fatigue conditions performed (p < 0.05). Mechanical and thermo-mechanical fatigue decreased the flexural strength results significantly for both ceramic-gold alloy (52 ± 6.6 and 53 ± 5.6 MPa, respectively) and ceramic-Ti cp combinations (29 ± 6.8 and 29 ± 6.8 MPa, respectively) compared to the control group (58 ± 7.8 and 39 ± 5.1 MPa, for gold and Ti cp, respectively) (p < 0.05) (Tukey's test). While ceramic-Ti cp combinations failed adhesively at the metal-opaque interface, gold alloy frameworks exhibited a residue of ceramic material on the surface in all experimental groups. Significance: Mechanical and thermo-mechanical fatigue conditions decreased the flexural strength values for both ceramic-gold alloy and ceramic-Ti cp combinations with the results being significantly lower for the latter in all experimental conditions. © 2007 Academy of Dental Materials.

Evaluation of temporomandibular joint noise in partially edentulous patients.

In order to evaluate the presence of TMD (temporomandibular disorder), dissatisfaction related to the use of removable partial dentures (RPD) and the effect of the treatment on temporomandibular joint noises, 13 female patients with Kennedy class I and II mandibular arch were selected. Another 13 young, asymptomatic, dentate patients, also female, were used as reference. After four years, 38.4% were found to have a moderate or severe degree of TMD. Over the four years, the degree of TMD increased in 46.15% of the patients, was not affected in 20.07%, while in 15.38% it decreased or the patients remained free from signs and symptoms. About 30% of the patients at the second year and 46% after the fourth year, had complaints regarding retention and stability. It was concluded that there is no relationship between TMD and the condition of partially edentulous Kennedy class I and II, but patient dissatisfaction increased after the second year and temporomandibular joint noise was reduced significantly with the replacement of the teeth.

Severe fracture of the maxillary alveolar process associated with extrusive luxation and tooth avulsion: A case report

Aim: The aim of this report is to present a case of severe fracture of the maxillary anterior alveolar process with substantial bone dislodgement associated with extrusive tooth luxation and avulsion. Background: Dentoalveolar trauma is a challenge to dentistry, especially in young patients, for it can lead to early tooth loss which compromises oral function, esthetics, self-esteem, and alter the long-term plan of care for the victim. Case Report: A 12-year-old girl with severe dentoalveolar trauma to the maxillary anterior region presented for emergency care for her injury. Treatment consisted of fracture reduction of the alveolar process, repositioning of the teeth that had suffered extrusive luxation, placement of a semi-rigid splint, and suturing of soft tissue lacerations. The traumatized teeth presented with pulpal necrosis and were treated endodontically. After 24 months of follow up, the fracture of the alveolar process was completely healed and the displaced teeth presented no signs of ankylosis or root resorption. Summary: First-aid care contributed remarkably to this case allowing the re-establishment of esthetics, function, and patient's self-esteem. In spite of trauma extension the treatment outcomes were favorable. Clinical Significance: Cases of dentoalveolar trauma should be evaluated on an individual basis. However, early emergency management and adequate follow-up can prevent further complications and contribute to treatment success.

Integrated clinical treatment of gingival recession secondary to root perforation: case report.

Among the factors that influence the success of treatment of a root perforation, its location and possibility of contamination are determinant because the interaction of these 2 factors may result in significant periodontal injury. The management of cases of hard-to-reach contaminated perforations depends on the choice of an adequate technique. In the case reported in this article, controlled orthodontic tooth extrusion was successfully performed to treat gingival recession secondary to root perforation. The outcomes showed that this technique preserves the zone of attached gingiva, maintains the crown height, and prevents the involvement of the supporting bone tissue. The favorable clinical and radio?graphic conditions after 7 years of follow-up demonstrate the viability of this treatment approach.