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1.
Pak J Med Sci ; 36(2): 85-90, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32063937

RESUMO

OBJECTIVE: The purpose of the present study was to assess dentin shear bond strength (SBS) and mode of bond failure of bioactive cement (BA) in comparison to conventional resin cement when photosensitized by Er,Cr: YSGG Laser (ECL). METHODS: The present in-vitro study was carried out from March 2019 to May 2019. Sixty permanent non-carious, intact, non-fractured molars were isolated and mounted vertically in acrylic resin. Buccal surface of each molar tooth was ground, polished and surface treated with ECL. Ketac conditioner was applied on the surface washed and air dried surface. Tetric -N-Bond adhesive was applied on forty-five samples and light cured. The specimens were allocated into four groups (n=15) according to the type of cement used i.e., Calibra (C), BA, Variolink II (V) and Maxcem-Elite (ME). For SBS testing was performed using the universal testing machine. Eight samples from each group were assessed for modes of failure. Means and standard deviations were compared using analysis of variance (ANOVA) and Tukey's post hoc test at a significance level of p < 0.05. RESULTS: The highest mean SBS was observed in group ECL-C (21.55±3.08). The lowest mean SBS was displayed in group ECL-ME (14.25±3.55). Mean SBS values for group ECL-C (21.55±3.08) and group ECL-V (20.74±4.15) were comparable (p <0.05). Similarly, SBS values of group ECL-BA (15.48±3.62) and group ECL-ME (14.25±3.55) were comparable (p <0.05). CONCLUSION: Dentin surface conditioned with Er,Cr: YSGG and bonded to C and V cements exhibit favourable bond strength values.

2.
J Prosthodont ; 28(2): 179-184, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28102922

RESUMO

PURPOSE: To evaluate in vitro the effect of the size of the unfilled space of the abutment screw access hole on the amount of extruded excess cement and the retention of zirconia copings. MATERIALS AND METHODS: Twelve dental implant replicas were attached to the corresponding abutments and embedded in acrylic resin blocks. A total of 36 CAD/CAM zirconia copings were fabricated by one technician using the standard technique. Abutments were divided into group I: the entire screw access channel was completely filled (nonspaced); group II: 1-mm-spaced; and group III: 2-mm-spaced. The copings were air-abraded and temporarily cemented under constant load of 60 N for 10 minutes. The excess cement was calculated as the difference between the post-cementation and post-excess-removal weights using a digital scale. Retention test was performed by a universal testing machine at a 0.5 mm/min crosshead speed. The ultimate force and tensile strength required for separation were recorded. One-way ANOVA and Tukey's test were used for statistical analysis at p ˂ 0.05. RESULTS: The average amount of extruded cement in groups 1, 2, and 3 was 33.48 ± 1.55, 23.05 ± 5.48, and 15.58 ± 5.98 mg, respectively. Multiple comparisons showed significant differences in the amount of extruded excess cement between the three groups (p ˂ 0.001). The maximum load at decementation in groups 1, 2, and 3 was 98.8, 87.5, and 88.6 N, respectively. Groups 1, 2, and 3 separated at 6.90 ± 1.2, 6.12 ± 0.7, and 6.21 ± 0.9 MPa, respectively, with no significant differences between them. CONCLUSIONS: The amount of extruded excess cement was reduced by more than half when a 2-mm space of the screw access hole was left unfilled in comparison to the nonspaced counterpart. The retention of zirconia copings was not affected by the reported technique.


Assuntos
Parafusos Ósseos , Coroas , Dente Suporte , Cimentos Dentários/química , Retenção em Prótese Dentária/métodos , Prótese Dentária Fixada por Implante , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Análise do Estresse Dentário , Resistência à Tração , Zircônio/química
3.
J Prosthet Dent ; 119(2): 263-269, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28552289

RESUMO

STATEMENT OF PROBLEM: The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. MATERIAL AND METHODS: Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-µm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). RESULTS: The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (P<.001). The mean marginal discrepancy (µm) of the pre-cemented group (29.5 ±8.2) was significantly different (P<.01) from that of the NS (72.3 ±13.7), the 1MMS (70.1 ±19), and the 2MMS group (70.1 ±18.8). No significant differences were found in marginal accuracy among the 3 test groups (P=.942). CONCLUSIONS: Within the limitations of this in vitro study, leaving a 2-mm space in the SAC reduced the amount of extruded excess cement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings.


Assuntos
Dente Suporte , Cimentos Dentários/uso terapêutico , Projeto do Implante Dentário-Pivô/métodos , Adaptação Marginal Dentária , Restauração Dentária Permanente/métodos , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Humanos , Técnicas In Vitro
4.
Clin Oral Implants Res ; 28(11): 1342-1347, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27743396

RESUMO

OBJECTIVE: The aim of the present 36-month prospective split-mouth clinical trial was to investigate the peri-implant soft tissue changes and crestal bone loss (CBL) around delayed loaded platform-switched implants placed at crestal and subcrestal levels. MATERIAL AND METHODS: Twenty-three individuals with bilaterally missing either mandibular first or second molars were included. The test and control sites were defined as follows: (i) test sites: implants placed 2 mm below the alveolar crest (subcrestal); (ii) control sites: implants placed at bone level (crestal). Forty-six implants (23 implants in test sites and 23 in control sites) were placed in the center of the healed alveolar ridge in the posterior mandible. Peri-implant bleeding on probing (BOP), probing depth (PD ≥ 4 mm), and CBL was compared at 6, 18, and 36 months of follow-up. P < 0.05 was considered statistically significant. RESULTS: Sixteen males and seven females with a mean age of 43.5 years (29-50) were included. In the control group (n = 23), the highest mean percentage of sites that showed BOP and PD ≥ 4 mm were at 6 months (7.4% and 1.4%, respectively). In the test group (n = 23), the highest mean percentage of sites that showed BOP and PD ≥ 4 mm were at 6 months (2.4% and 1.2%, respectively). The total amount of CBL around crestal and subcrestal implants after 36 months of loading was 0.45 ± 0.2 and 0.3 ± 0.2 mm, respectively. At all follow-up intervals, all intragroup and intergroup comparisons showed no significant differences in BOP, PD ≥ 4 mm, and CBL around implants placed at crestal and subcrestal levels. CONCLUSION: Up to 36 months of follow-up, soft tissue parameters and crestal bone levels can remain equally stable around dental implants placed at crestal and subcrestal levels. The need for long-term follow-up clinical trials is also emphasized.


Assuntos
Perda do Osso Alveolar/etiologia , Projeto do Implante Dentário-Pivô/métodos , Implantação Dentária Endóssea/métodos , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Projeto do Implante Dentário-Pivô/efeitos adversos , Implantação Dentária Endóssea/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Periodonto/diagnóstico por imagem , Periodonto/patologia , Estudos Prospectivos , Radiografia Dentária Digital
5.
Clin Oral Implants Res ; 28(10): 1182-1187, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27469294

RESUMO

OBJECTIVE: To compare the clinical and radiographic parameters around short (6 to 8 mm in length) and long (11 mm in length) dental implants placed in patients with and without type 2 diabetes mellitus (T2DM). MATERIAL AND METHODS: Forty-five male patients with T2DM (Group-1) and 42 male non-diabetic controls (Group-2) who had undergone implant therapy in the posterior mandible were included. Depending upon the length of the implant, patients were divided into two subgroups: (a) patients with short implants (6-8 mm long) and (b) patients with long implants (11 mm long). Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and crestal bone loss (CBL) were measured at 18 and 36 months of follow-up in both groups. Hemoglobin A1c (HbA1c) levels were measured at baseline and after 18 and 36 months of follow-up in both groups. P-values less than 0.05 were considered statistically significant. RESULTS: The mean age of patients in groups 1 and 2 was 42.5 and 40.6 years, respectively. The mean HbA1c levels at baseline among patients in groups 1 and 2 were 7.7% and 4.5%, respectively. At 18 and 36 months of follow-up, the mean HbA1c levels among patients in groups 1 and 2 were 6.6% and 4.5% and 6.5% and 4.4%, respectively. The mean duration of T2DM among patients that received short and long implants was 4.3 years and 4.1 years, respectively. There was no significant difference in PI, BOP, PD and CBL around implants placed in both groups at 18 and 36 months of follow-up. Success rate of short and long dental implants was 100% in both groups. CONCLUSION: Short implants can demonstrate clinical and radiographic stability in a manner similar to conventional long implants in patients with and without T2DM. The role of oral hygiene and glycemic maintenance in this scenario cannot be disregarded.


Assuntos
Implantes Dentários , Planejamento de Prótese Dentária , Diabetes Mellitus Tipo 2 , Seguimentos , Adulto , Humanos , Masculino , Radiografia Dentária , Fatores de Tempo , Resultado do Tratamento
6.
J Prosthodont ; 26(3): 252-260, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27379723

RESUMO

PURPOSE: To propose a length-and-diameter-based classification scheme for dental implants to standardize terminology in the dental literature and communication between interested parties. MATERIALS AND METHODS: This study was mainly based on searching two major resources: published scientific research papers and 14 of the most popular dental implant manufacturers. Indexed databases were searched from January 2004 up to and including February 2016 using the keywords "dental implant length" and "dental implant diameter." Retrieved titles and abstracts were screened, and related full-text articles were reviewed. Full-text articles that clearly stated the terms and measurements of implants used were included and considered for proposing this classification scheme. RESULTS: The initial search for implant diameter and length yielded 1007 and 936 articles, respectively. A total of 85 studies (41 about diameter, 44 about length) were selected and reviewed. The remaining studies (966 about diameter, 892 about length) that did not abide by the eligibility criteria were excluded. The terms "long," "short," "standard," "wide," and "narrow" were the most commonly used terms in the literature. A classification scheme for implants by diameter and length was proposed. CONCLUSIONS: Indexed publications contain a variety of terms used by authors to describe diameter and length of dental implants without conformity and standardization. The classification scheme proposed in this article could serve as a reference for interested parties.


Assuntos
Implantes Dentários/classificação , Planejamento de Prótese Dentária/classificação , Humanos , Terminologia como Assunto
7.
J Contemp Dent Pract ; 17(10): 826-829, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27794153

RESUMO

OBJECTIVE: This study aimed to gain more information from complete denture (CD) wearers who did not receive dental implants, of the reasons preventing them from using implants to retain their CD in a selected sample of dental patients in Riyadh, Saudi Arabia. MATERIALS AND METHODS: A paper-and-pencil questionnaire containing 20 direct questions of the possible reasons preventing CD wearers from receiving implants to retain their dentures was distributed in three different places in Riyadh, Saudi Arabia. RESULTS: A total of 270 subjects were included in this survey. The results showed that 180 (66.7%) patients indicated that the fear of pain associated with implant placement was the main reason preventing them from receiving an implant treatment, followed by fear of the surgical procedure (175, 64.8%), fear of postoperative complications (166, 61.5%), information from other people about the various problems associated with implant treatment (154, 57%), and finally cost of the implant (141, 52.2%). CONCLUSION: Fear is the main reason preventing CD wearers from receiving implant treatment. Therefore, it is essential for dentists to be familiar with the reasons for implant refusal to overcome a common, yet an influential obstacle.


Assuntos
Atitude Frente a Saúde , Implantes Dentários/psicologia , Prótese Total , Adulto , Idoso , Idoso de 80 Anos ou mais , Implantes Dentários/economia , Medo/psicologia , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Dor/psicologia , Complicações Pós-Operatórias/psicologia , Inquéritos e Questionários
8.
J Contemp Dent Pract ; 12(5): 327-32, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22269191

RESUMO

UNLABELLED: Learning fine motor skills is a pre-requisite for succeeding in dental practice and it is sometimes challenging for dental students. Most of the methods used in the selection process depend on evaluation of intellectual ability or structured interview while manual competence is not. However, no test on aptitude or manual dexterity is used as criteria. OBJECTIVE: The purpose of the present study intended to evaluate the fine motor skills of beginning dental students which could in turn be used as a method of selection of students for the dental degree admission process. MATERIALS AND METHODS: A study was conducted among 71 second year dental students at College of Dentistry, King Saud University in Riyadh. A test composed of three parts, writing an answer for a question in four lines, drawing a picture of a smile and doing a class 1 amalgam preparation on a plastic molar tooth. The students were evaluated based on their handwriting, basic drawing skills and their skills in performing the tooth preparation by experts in each fields following certain criteria. RESULTS: The results showed a significant correlation between writing and drawing skills and dental skills of the student with p < 0.001. CONCLUSIONS: The results of the current study support the use of the writing or drawing test as one of the test used for the applicants for dental school admission. However, the value given to such test in the selection of students needs further investigations and consensus.


Assuntos
Arte , Escrita Manual , Destreza Motora/fisiologia , Estudantes de Odontologia , Aptidão/classificação , Amálgama Dentário , Preparo da Cavidade Dentária/classificação , Preparo da Cavidade Dentária/instrumentação , Equipamentos Odontológicos de Alta Rotação , Humanos , Masculino , Dente Molar/anatomia & histologia , Arábia Saudita , Critérios de Admissão Escolar , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-33535384

RESUMO

OBJECTIVES: The aim of this study was to investigate and compare the level of halitosis in patients with/without fixed crowns and in addition the influence of various crown parameters on halitosis was also explored. METHODS: In total, 96 subjects (fixed crowns = 52; no crowns = 44) participated in the study. The levels volatile sulphur compounds (VSCs) of hydrogen sulphide (H2S), methyl mercaptan (CH3SH), and dimethyl sulphide (CH3SCH3) were evaluated with breath samples using gas chromatography and used for classification as presence or absence of halitosis. The periodontal clinical parameters for all the participants as well as the crown parameters for participants with fixed crowns were also evaluated. Cross tabulation, Chi-square test, and one-way analysis of variance tests were used for the statistical analysis and comparisons. RESULTS: Breath samples revealed, 50 (52.1%) participants were suffering from halitosis. Out of VSCs, the level of CH3SCH3 (62.5%) was found to be the most prevalent. Significant correlations were observed between the presence of fixed crowns and oral halitosis (p < 0.001). Statistically significant difference in the concentration of H2S and CH3SH (p < 0.001) and no significance for CH3SCH3 (p = 0.075) between patients with/without fixed crowns was found. The presence of halitosis was more prevalent in the subjects with crown parameters (subgingival margin, over-contoured margin, open-crown margin, over-contoured and under-contoured crowns) considered clinically defective/unacceptable (p < 0.05). CONCLUSIONS: Presence of fixed dental crowns significantly contributes to the oral halitosis. Dental crowns with defects significantly impair the hygienic conditions and oral microflora resulting in high prevalence of halitosis.


Assuntos
Halitose , Sulfeto de Hidrogênio , Cromatografia Gasosa , Coroas , Halitose/epidemiologia , Humanos , Compostos de Enxofre
10.
Int J Oral Maxillofac Implants ; 34(3): 605­621, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30703180

RESUMO

PURPOSE: Dental implant placement in atrophic ridges is challenged by availability of bone and proximity to vital structures. Although short dental implants have been considered favorable, there is no consensus regarding their long-term survival and factors affecting it. This systematic review addressed the focused question, "What is the survival rate of short dental implants (SDI; length ≤ 6.5 mm) placed in posterior edentulous ridges without any ridge augmentation procedures and followed up for 12 months post-prosthetic loading, and what are the factors affecting their survival?" MATERIALS AND METHODS: Based on a search of the indexed literature, 51 studies fulfilling the inclusion criteria were quantitatively reviewed. Overall SDI survival and factors influencing survival, such as anatomic location, surgical protocol, time of loading, type of prosthesis retention, nature of prosthesis, implant stability, crown-to-implant ratio (C/I ratio), and marginal bone loss at follow-up were evaluated. SDI survival based on clinical factors was compared to overall survival using odds ratio (OR), and continuously distributed data were evaluated using Pearson's correlation (P < .05). RESULTS AND CONCLUSION: Based on this review, SDI placed in edentulous posterior regions of the maxilla and mandible have survival rates (96.45%) similar to those of conventional-length implants after a follow-up period of 12 months post-prosthetic loading. Except for smaller implant diameter (OR = 1.59, 95% confidence interval [CI] = 1.03-2.43, P < .05), screw-retained restorations (OR = 2.11, 95% CI = 1.25-3.57, P < .01), and C/I ratio ≥ 2 (Pearson's R = -0.694, P < .01), other variables relating to implant surgery, prosthetic loading, nature and type of prosthesis, and follow-up did not significantly affect SDI survival.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Seguimentos , Maxila , Taxa de Sobrevida , Resultado do Tratamento
11.
J Prosthodont ; 17(6): 502-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18544130

RESUMO

Several methods of classification of partially edentulous arches have been proposed and are in use. The most familiar classifications are those originally proposed by Kennedy, Cummer, and Bailyn. None of these classification systems include implants, simply because most of them were proposed before implants became widely accepted. At this time, there is no classification system for partially edentulous arches incorporating implants placed or to be placed in the edentulous spaces for a removable partial denture (RPD). This article proposes a simple classification system for partially edentulous arches with implants based on the Kennedy classification system, with modification, to be used for RPDs. It incorporates the number and positions of implants placed or to be placed in the edentulous areas. A different name, Implant-Corrected Kennedy (ICK) Classification System, is given to the new classification system to be differentiated from other partially edentulous arch classification systems.


Assuntos
Arcada Parcialmente Edêntula/classificação , Arco Dental/patologia , Implantes Dentários/classificação , Prótese Parcial Removível/classificação , Humanos , Mandíbula/patologia , Maxila/patologia , Terminologia como Assunto , Dente/patologia
12.
Photomed Laser Surg ; 36(8): 431-438, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29683407

RESUMO

BACKGROUND: The available evidence of Er,Cr:YSGG lasers on bleached enamel is limited and controversial. It is assumed that Er,Cr:YSGG laser will be effective in reversing the effect of bleaching on adhesive bond integrity of enamel to resin composite. OBJECTIVE: The study aimed to evaluate the efficacy of Er,Cr:YSGG laser on bond strength and microleakage of bleached enamel. MATERIALS AND METHODS: From the 80 samples, 60 samples were bleached (40% hydrogen peroxide) and divided into three subgroups. Twenty bleached samples in each subgroup were exposed to 10% sodium ascorbate (Gp A), Er,Cr:YSGG laser (50 Hz and 4.5 W) (Gp L), and no treatment (Gp B), respectively. Twenty samples were not bleached (Control-C). Using etch and rinse technique, resin composite was built-up on enamel and photopolymerized. Ten specimens in each group were tested for shear bond strength at a crosshead speed of 1 mm/min. Ten specimens in each group were tested for microleakage using 2% methylene blue. Data were analyzed using analysis of variance (ANOVA) and Tukey post hoc multiple comparisons test. RESULTS: The mean bond strength of specimens in group L (30.83 ± 1.7000) was comparable with group A (31.38 ± 2.03) and was significantly higher than bleached specimens (9.49 ± 0.86) (p < 0.001). The highest mean microleakage values were observed in bleached group (630.32 ± 156.58). The mean microleakage among control (36.66 ± 27.33) and laser group specimens (55.32 ± 34.98) was comparable (p > 0.05). CONCLUSIONS: Treatment of bleached enamel with erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser showed a significant reversal effect on the enamel bond strength and microleakage scores. CLINICAL SIGNIFICANCE: Er,Cr:YSGG laser (50 Hz, 4.5 W) treatment has the potential to restore the bond strength of bleached enamel to resin composite.


Assuntos
Ácido Ascórbico/farmacologia , Resinas Compostas/química , Colagem Dentária/métodos , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Infiltração Dentária/etiologia , Peróxido de Hidrogênio/farmacologia , Clareadores Dentários/farmacologia , Esmalte Dentário/química , Corrosão Dentária , Análise do Estresse Dentário , Humanos , Lasers de Estado Sólido , Resistência ao Cisalhamento
13.
Saudi Dent J ; 28(4): 183-188, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27872549

RESUMO

OBJECTIVE: There were four aims of the current study: (1) to find the most commonly used Tooth Numbering System (TNS) in Saudi Arabia in both academic and non-academic institutions, (2) to identify the most commonly taught TNS in dental colleges, (3) to understand the reasons why dental practitioners prefer to use a specific TNS, and (4) the consequences of using more than one TNS. MATERIALS AND METHOD: Between May 2014 and May 2015, a self-administered questionnaire containing 21 questions was randomly distributed to 121 individuals (20 deans of dental colleges and 101 heads of governmental dental centers). RESULTS: The most commonly used TNS is the Fédération Dentaire Internationale (FDI) TNS for both primary and permanent dentitions in both academic and non-academic institutions, followed by the Palmer TNS and then the Universal TNS. CONCLUSION: The FDI TNS proved to be the most taught TNS in dental colleges in Saudi Arabia. It is advised that the FDI TNS be implemented as a unified system in Saudi Arabia due to the advantages of this particular TNS and the benefits of using one single TNS.

14.
Aust Endod J ; 42(3): 124-131, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26992005

RESUMO

The aim was to investigate in vitro the fracture resistance (FR) of endodontically treated teeth (ETT) with conservative access cavity restored using various direct and indirect restorative materials and techniques. Seventy-two mandibular first molars were equally divided into six groups. Teeth in Group 1 were untreated (controls). In Groups 2, 3, 4, 5 and 6, teeth were restored with amalgam, composite resin, ceramic inlay, ceramic onlay and zirconium crown, respectively. A fracture test was performed on all teeth using a static load. Compared with other groups, teeth in Groups 3 (P < 0.05) and 6 (P < 0.05) had the highest FR values with no significant difference in-between them. Teeth in Group 4 had the lowest FR than other groups (P < 0.05). All restorative techniques tested led to a significant reduction in FR. It is necessary to consider type of fracture when evaluating fracture resistance of endodontically treated teeth. Crowned molars had the highest favourable fractures among the five treatment groups. Although the results of this in vitro study showed variations between tested techniques in ETT with a conservative access cavity, further long-term controlled clinical trials are required to confirm these in vitro findings.


Assuntos
Restauração Dentária Permanente , Fraturas dos Dentes , Dente não Vital , Resinas Compostas , Análise do Estresse Dentário , Humanos , Dente Molar
15.
J Biomed Mater Res A ; 103(1): 300-10, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24659523

RESUMO

Calcium phosphate (CaP) ceramic coatings have been used to enhance the biocompatibility and osteoconductive properties of metallic implants. The chemical composition of these ceramic coatings is an important parameter, which can influence the final bone performance of the implant. In this study, the effect of phase composition of CaP-sputtered coatings was investigated on in vitro dissolution behavior and in vivo bone response. Coatings were prepared by a radio frequency (RF) magnetron sputtering technique; three types of CaP target materials were used to obtain coatings with different stoichiometry and calcium to phosphate ratios (hydroxyapatite (HA), α-tricalciumphosphate (α-TCP), and tetracalciumphosphate (TTCP)) were compared with non-coated titanium controls. The applied ceramic coatings were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and inductively coupled plasma optical emission spectroscopy. The in vitro dissolution/precipitation of the CaP coatings was evaluated using immersion tests in simulated body fluid (SBF). To mimic the in vivo situation, identical CaP coatings were also evaluated in a femoral condyle rabbit model. TCPH and TTCPH showed morphological changes during 4-week immersion in SBF. The results of bone implant contact (BIC) and peri-implant bone volume (BV) showed a similar response for all experimental coatings. An apparent increase in tartrate resistant acid phosphatase (TRAP) positive staining was observed in the peri-implant region with decreasing coating stability. In conclusion, the experimental groups showed different coating properties when tested in vitro and an apparent increase in bone remodeling with increasing coating dissolution in vivo.


Assuntos
Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis , Animais , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Microtomografia por Raio-X
16.
J Dent Educ ; 77(1): 105-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23314474

RESUMO

The purpose of this study was to survey left-handed (LH) dental students and interns concerning whether they face any problems in their dental education or in their practice of dentistry. The questionnaires were distributed in four dental colleges in different regions in Saudi Arabia. The questionnaire was comprised of sixteen questions to assess the following issues: demographic information, difficulties in dental school or dental practice due to left-handedness, preferred hand in performing different dental procedures, and musculoskeletal complications. The study found that the percentage of LH dental students was around 7 percent (110 out of 1,660). More than half of these participants (n=56) reported that being LH is not a problem in general, while when performing the required dental work, around 51 percent (n=56) agreed to having a problem. The majority (68 percent; n=75) reported that they had a problem with having RH instructors, and 84.5 percent (n=93) responded that their institution is not properly equipped to accommodate LH students. Only 34 percent (n=37) agreed that using facilities of an RH dentist may cause musculoskeletal complications to an LH dentist. The results of this study suggest that dental schools should provide LH students with appropriate equipment and a proper learning environment.


Assuntos
Lateralidade Funcional , Estudantes de Odontologia , Adulto , Distribuição de Qui-Quadrado , Equipamentos Odontológicos , Educação em Odontologia , Feminino , Humanos , Internato e Residência , Masculino , Atividade Motora , Arábia Saudita , Faculdades de Odontologia , Estudantes de Odontologia/psicologia , Estudantes de Odontologia/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
17.
Int J Prosthodont ; 24(1): 64-70, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21210007

RESUMO

PURPOSE: The aim of this study was to evaluate the existence of different esthetic smile criteria as determined on the smiles of celebrities, which were considered by lay people to be beautiful. MATERIALS AND METHODS: An Internet search for "best smile" and "female celebrities" in the years 2007 and 2008 identified 50 celebrities who were voted to have beautiful smiles. Another search was made for images of these celebrities that showed the entire face with an open smile. The images were analyzed using Digimizer image analysis software for different esthetic smile criteria. RESULTS: Eighty percent of the sample was classified as having an average upper lip position, 62% showed upward upper lip curvature, and 78% had a parallel smile line. Forty-two percent of the images showed the maxillary anterior teeth not touching the lower lip, while 34% were touching, and 24% slightly covered it. Sixty percent displayed up to the second premolar, and 32% displayed up to the first molar when smiling. Midline deviation was detected in 36% of the sample. Diastema and golden proportion were not seen in any of the subjects. CONCLUSION: Female celebrities voted to have the best smile by lay people showed most of the esthetic smile criteria with slight variations, except for the golden proportion. The opinions and perceptions of lay people about beauty should be studied and evaluated.


Assuntos
Estética Dentária , Sorriso , Dente Pré-Molar/anatomia & histologia , Dente Canino/anatomia & histologia , Pessoas Famosas , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Incisivo/anatomia & histologia , Internet , Lábio/anatomia & histologia , Maxila , Dente Molar/anatomia & histologia , Fotografação , Opinião Pública , Percepção Visual
18.
Saudi Dent J ; 22(4): 183-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23960495

RESUMO

AIM: The purpose of this survey was to assess the level, sources, and need for information about dental implants among a selected sample of dental patients in Riyadh, Saudi Arabia. MATERIALS AND METHODS: Patients' knowledge and awareness in using dental implants as an option in replacing missing teeth were evaluated through a standardized self- explanatory questionnaire distributed in two places in Riyadh: Military Hospital and College of Dentistry, King Saud University (Darraiyah campus). The questionnaires were handed to the patients during their regular dental visits. A total of 379 subjects were included in this survey. RESULTS: The results of this study indicate that 66.4% of the subjects knew about dental implants. The subjects' friends and their relatives were the main source of information about dental implants for 31.5% of the subjects, and dentists were the secondary source for 28.3% of the sample. About 82.4% of the subjects need more information about dental implants and 85.2% of them chose the dentist to be the desired source for such information, followed by the internet in 28.5% of the cases. Almost 74.4% of those surveyed did not know if their regular dentists use dental implants. High cost was the major factor in preventing patients from choosing implants in 86.5% of the cases while the long treatment time and fear of surgery was the factor in 71% and 68.6% of the subjects, respectively. CONCLUSION: The results of this survey showed an acceptable level of awareness about dental implants among a selected sample of dental patients in Riyadh. It also showed the need for providing more general and accurate information to the patients about this treatment modality.

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