Research Publications

Permanent URI for this collection

https://hdl.handle.net/10566/407

Browse

Now showing 1 - 20 of 42

Extra-oral suction
(MDPI, 2023) Noordien, Naeemah; Mulder-van Staden, Suné; Mulder, Riaan
Oral health care workers (OHCW) are exposed to pathogenic microorganisms during dental aerosol-generating procedures. Technologies aimed at the reduction of aerosol, droplets and splatter are essential. This in vivo study assessed aerosol, droplet and splatter contamination in a simulated clinical scenario. The coolant of the high-speed air turbine was colored with red concentrate. The red aerosol, droplets and splatter contamination on the wrists of the OHCW and chests of the OHCW/volunteer protective gowns, were assessed and quantified in cm2 . The efficacy of various evacuation strategies was assessed: low-volume saliva ejector (LV) alone, high-volume evacuator (HV) plus LV and an extra-oral dental aerosol suction device (DASD) plus LV. The Kruskal– Wallis rank-sum test for multiple independent samples with a post-hoc test was used. No significant difference between the LV alone compared to the HV plus LV was demonstrated (p = 0.372059). The DASD combined with LV resulted in a 62% reduction of contamination of the OHCW. The HV plus LV reduced contamination by 53% compared to LV alone (p = 0.019945). The DASD demonstrated a 50% reduction in the contamination of the OHCWs wrists and a 30% reduction in chest contamination compared to HV plus LV. The DASD in conjunction with LV was more effective in reducing aerosol, droplets and splatter than HV plus LV.
A mass guide for the harvest of cortico-cancellous bone from the posterior iliac crest for mandibular reconstruction
(UWC, 2019) Reyneke, J
This study sought to find the mass of particulate cortico-cancellous bone graft required per 1 cm continuity defect of the mandible. Harvested bone was weighed, milled and maximally compressed in a syringe. The defect length (DL) was measured in centimetres, and the compressed bone volume (CBV) used was recorded. The wet bone mass (WBM) of bone required per centimetre of mandibular defect, and the mass of bone yielding 1cc of compressed bone was calculated. Results were analysed statistically to determine if clinically meaningful differences exist between male and female iliac crest. Forty three patient records were reviewed (28 female). Thirty patients had bilateral, and 13 patients had unilateral iliac crest harvest. Mean WBM used per centimetre of mandible defect was 6.9 g.WBM required to produce 1cc of CBV was 2.0 g. For the bilateral harvest group the mean DL was 10.3 cm, the mean WBM was 66.7 g, and the mean CBV was 33.9cc. There was no significant difference in mean WBM between male (72.8 g) and female (62 g) patients. The mean CBV for males (39.7 g) was significantly higher than females (29.5 g). For patients who had unilateral harvest the mean DL was 7.7 cm, the mean WBM harvested was 59.1 g, and the mean CBV was 29.4cc. The mean wet bone mass of posterior iliac crest required to graft each centimetre of mandibular segmental defect is 6.9 grams. A unilateral posterior iliac crest harvest will yield on average 59.1 grams of bone whilst a bilateral posterior iliac crest harvest will yield on average 66.7 grams
Osteoma of the mandibular condyle: a rare case report and review of the literature
(UWC, 2019) Ostrofsky, M
Introduction: Osteoma is a rare slow-growing benign neoplasm which is often asymptomatic and composed of mature bone. Only 21 cases were previously reported in the mandibular condyle. Observation: A 60 year old male presented with gross asymmetry of the lower jaw and reduced function. He mentioned that he was involved in an accident to the head about 16 years ago. Upon examination, it was noticed that the chin deviated to the left with some discomfort during function. Computed tomography revealed a radiopaque mass medial to the left condylar pole. The lesion was gradually increasing in size and in close proximity to the middle cranial fossa. A condylectomy was performed using a pre-auricular approach. A diagnosis of osteoma was confirmed histopathologically. The defect was reconstructed with stock TMJ prostheses. Discussion: Osteomas affecting the condyle have significant functional implications and should be considered when deviation of the mandible is present.
Dentinogenesis imperfecta in Osteogenesis imperfecta type XI in South Africa: a genotype–phenotype correlation
(UWC, 2019) Chetty, M
BACKGROUND: The maxillofacial and dental manifestations of Osteogenesis imperfecta (OI) have significant implications in terms of management. Although the occurrence of abnormal dentine in some forms of OI is well documented, there is scant information on the association of abnormal dentine in the Black African persons with phenotypic OI III and genotypic OI XI in South Africa. METHODS: This was a cross-sectional analytic study. A series of 64 Black South African individuals with a confirmed phenotypic diagnosis of OI III, ages ranging from 3 months to 29 years, were assessed clinically, radiographically, and at a molecular level. RESULTS: A total number of 64 saliva samples were analyzed and 3 DNA variations were identified in exon 5 of the FKBP10 gene. The homozygous mutation, c.[831dupC]; [831dupC], was identified in 23 affected persons who had no clinically obvious features of DI in their primary and secondary teeth. Radiologically, mild features of DI were evident in 10 persons in whom radiographic images were obtained and were given a Clinical–radiological score of 2. A compound heterozygous mutation, c. [831delC]; [831dupC], was identified in three siblings. An intraoral examination of these affected persons revealed no clinically apparent features of DI in their primary and secondary teeth. Due to the lack of radiological facilities, the presence or absence of DI could not be confirmed or negated. A second compound heterozygous mutation, c.[831dupC]; [1400-4C>G], was identified in a female of 29 years belonging to the Xhosa linguistic group. Her teeth appeared clinically normal but it was not possible to obtain radiographs. In 37 affected individuals, no disease-causing mutations were identified. CONCLUSION: Black African individuals in SA with the homozygous mutation in the FKBP10 gene have clinically unaffected teeth yet exhibited radiographic features of DI to varying degrees. This characterization is suggestive of a relationship between the genetic abnormality and the clinical manifestations of DI. The authors suggest that this diagnosis must include teeth that are clinically and/or radiologically aberrant, and should not exclude the presence of other, milder, dentinal aberrations associated with OI. There was no correlation between severity of OI and DI in this cohort of individuals.
Radiographic outcome of secondary alveolar bone grafting in patients with alveolar clefts
(John Wiley & Sons, 2021) Bellardie, Haydn
Objective: To determine the outcome of secondary alveolar bone grafting (SABG) in a series of consecutive patients with clefts involving the alveolus.Design and Setting: Retrospective cohort study of consecutive operations per-formed between June 2011 and September 2016 by a single surgeon at a single United Kingdom cleft center.Participants: A total of 160 patients with a cleft/s involving the alveolus, inclusive of syndromic patients and those with atypical facial clefts.Interventions: A standard protocol involved an oral hygiene program, pre-surgical orthodontics where necessary and autologous bone grafting from the iliac crest.Main Outcome Measure(s): The Kindelan bone-fill index was used to evaluate suc-cess using occlusal radiographs. Weighted Cohen's kappa coefficient was used as a measure of intra- and inter- rater agreement. Fisher's exact test was used to examine the effects of type of cleft, pre-surgical orthodontics or age at time of SABG on ra-diographic outcome.Results: There were 200 SABGs assessed. Mean age at time of SABG was 9.1 years old (SD 1.1) with 99% (n =198) of grafts deemed successful. There were two fail-ures where re- graft was performed successfully during the study period. A grade 1 outcome was achieved for 92.5% (n = 185) of grafts and this did not appear to be af-fected by type of cleft (P= .290), pre-surgical orthodontics (P= .380) or age at time of SABG (P= .081).Conclusions: The high success rate reported in this study supports the favorable out-comes of a high-volume cleft surgeon. These findings can be used for comparative audit with similar units providing cleft care.
In vitro analysis of techniques that alter the surface hardness of a glass ionomer restorative material
(Jaypee Brothers Medical Publishers, 2019) Mulder, Riaan; Noordien, Naeemah; Rossouw, Shaun
Ab s t r A c t Aim: The aim of this in vitro study was to compare the eect of dierent manipulation techniques on the surface hardness of ChemFil Rock glass ionomer.Materials and methods: The changes in Vickers surface hardness ( VH) of ChemFil Rock were evaluated after the application of ve manipulation techniques and compared with one control group (n = 60). The manipulation techniques included: nger pressure set, electronic piezo producing a high frequency set, air piezo producing a low frequency set, heat-set achieved with a curing light and the last technique was a combination of electronic piezo followed by heat-set. Standard set was the control.Results: The average surface hardness for the standard set was 49.5 VH. No statistical dierences were demonstrated when the means were compared for nger pressure set (49.2 VH) or the air piezo set (48.49 VH) with standard set. The electronic piezo (54.21 VH) and the heat-set (57.5 VH) had an increased mean surface hardness when compared to other techniques. Heat-set had the highest surface hardness demonstrating a signicant statistical dierence when compared with standard set, nger pressure set, air piezo set as well as the combination of electronic piezo (p < 0.05).Conclusion: The surface hardness of the glass ionomer cement (GIC) material assessed in this study can be predictably improved by applying the heat-set technique. A command set can be achieved with the electronic piezo or the air piezo, however, the surface hardness will only increase with the use of the electronic piezo.
Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: Comparison of dental arch relationships and dental indices at 5, 8, and 10 years
(Oxford University Press, 2021) Bellardie, Haydn; Heliövaara, Arja; Küseler, Annelise
Background and trial design: The Scandcleft intercentre study evaluates the outcomes of four surgical protocols (common method Arm A, and methods B, C, and D) for treatment of children with unilateral cleft lip and palate (UCLP) in a set of three randomized trials of primary surgery (Trials 1, 2, and 3). Objectives: To evaluate and compare dental arch relationships of 5-, 8-, and 10-year-old children with UCLP after four different protocols of primary surgery and to compare three dental indices. The results are secondary outcomes of the overall trial. Methods: Study models taken at the ages of 5 (n = 418), 8 (n = 411), and 10 years (n = 410) were analysed by a blinded panel of orthodontists using the Eurocran index, the 5-year-olds' (5YO) index, and the GOSLON Yardstick. Student's t-test, Pearson's correlation, chi-square test, and kappa statistics were used in statistical analyses. Results: The reliability of the dental indices varied between moderate and very good, and those of the Eurocran palatal index varied between fair and very good. Significant correlations existed between the dental indices at all ages. No differences were found in the mean 5-, 8-, and 10-year index scores or their distributions within surgical trials. Comparisons between trials detected significantly better mean index scores in Trial 2 Arm C (at all ages) and in Trial 1 Arm B (at 5 and 10 years of age) than in Trial 3 Arm D. The mean Eurocran dental index scores of the total material at 5, 8, and 10 years of age were 2.50, 2.60, and 2.26, and those of the 5YO index and GOSLON Yardstick were 2.77, 2.90, and 2.54, respectively. At age 10 years, 75.8% of the patients had had orthodontic treatment. Conclusions: The results of these three trials do not provide evidence that one surgical method is superior to the others. The reliabilities of the dental indices were acceptable, and significant correlations existed between the indices at all ages. The reliability of the Eurocran palatal index was questionable. Trial registration: ISRCTN29932826.
In vitro analysis of techniques that alter the surface hardness of a glass ionomer restorative material
(Original research, 2019) Mulder, Riaan
Glass ionomer cement as restorative materials are advantageous in pediatric restorative dentistry. The main advantages of GIC include fluoride release up to 50 μg/cm and a chemical adhesion to the tooth structure
Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: dental anomalies in 8-year olds
(European Journal of Orthodontics, 2020) Bellardie, Haydn
Background: Children born with unilateral cleft lip and palate (UCLP) are reported to display several dental anomalies including agenesis, supernumeraries, as well as variations in dental size, shape, and path of eruption. The extensive sample of individuals with UCLP included in the Scandcleft randomized control trials offers the opportunity to study more rare conditions, which is seldom possible with limited samples. Objectives: The aim was to study dental anomalies at 8 years of age in children born with UCLP included in the Scandcleft randomized control trials. Methods: Panoramic and intraoral radiographs from 425 individuals (279 males and 146 females) with a mean age of 8.1 years were assessed by four orthodontists regarding dental anomalies. Results: Agenesis was found in 52.5 per cent and supernumerary teeth in 16.9 per cent of the participants. The cleft lateral was missing in 43.8 per cent and was found peg shaped in 44.7 per cent. The distribution of ectopic eruption was 14.6 per cent, mainly affecting maxillary first molars, while transposition was found in 3.4 per cent of the individuals. In addition, infraocclusion of one or several primary molars was registered in 7.2 per cent of the participants. Conclusion: We conclude that 8-year-old children born with UCLP display multiple dental anomalies. The Scandcleft sample allowed rarely studied conditions such as infraocclusion of primary molars and transposition to be studied in children born with UCLP
Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: maxillary growth at eight years of age
(European Journal of Orthodontics, 2022) Bellardie, Haydn
Objectives: To assess differences in craniofacial growth at 8 years of age according to the different protocols for primary cleft surgery in the Scandcleft project. Design and setting: Prospective, randomized, controlled clinical trial (RCT) involving 10 centres, including non-syndromic Caucasians with unilateral cleft lip and palate (UCLP). In Trial 1, a common surgical method (1a) with soft palate closure at 3–4 months of age and hard palate closure at 12 months of age was tested against similar surgery but with hard palate repair at 36 months (delayed hard palate closure) (1b). In Trial 2, the common method (2a) was tested against simultaneous closure of both hard and soft palate at 1 year (2c). In Trial 3, the common method (3a) was tested against hard palate closure together with lip closure at 3 months of age and soft palate closure at 1 year of age (3d). Participants were randomly allocated by use of a dice. Operator blinding was not possible but all raters of all outcomes were blinded. Subjects and methods: The total number of participating patients at 8 years of age was 429. Lateral cephalograms (n = 408) were analysed. The cephalometric angles SNA and ANB were chosen for assessing maxillary growth for this part of the presentation. Results: Within each trial (Trial 1a/1b, Trial 2a/2c, and Trial 3a/3d), there was no difference in cephalometric values between the common and the local arm. There were no statistically significant differences in the SNA and ANB angles between the common arm in Trial 1a (mean SNA 77.8, mean ANB 2.6) and Trial 2a (mean SNA 79.8, mean ANB 3.6) and no difference between Trial 1a and Trial 3a, but a statistical difference could be seen between Trial 2a and Trial 3a (mean SNA 76.9, mean ANB 1.7). However, the confidence interval was rather large. Intra- and inter-rater reliability were within acceptable range.
Orthodontic treatment of bilateral transposition of maxillary canines and lateral incisors
(Hindawi, 2022) Nyakale, Mandla Dominic
Dental transposition is a severe disturbance of tooth position and its eruptive sequence. It may affect any tooth, and it may occur at any location within the dental arch, although some teeth may be more frequently affected than others. There are several types of dental transposition, and their classification depends on the type of teeth involved. The aetiology of transposition is not very clear and has always been the subject of controversies, and it is still not completely understood. The prevalence of dental transposition and the factors related to this dental anomaly have been well documented in the literature. When treating dental transposition, many factors which may affect the treatment results must be considered, such as aesthetics, occlusion, treatment duration, patient comfort, patient cooperation, and periodontal support. Various treatment options are currently available for the treatment of dental transposition. Successful treatment outcomes depend on the patient’s age, concern about facial and dental aesthetics, motivation of the patient, functional requirements, type of malocclusion, and the position of the root apices. The present case report is aimed at outlining the orthodontic treatment of a young adult patient diagnosed with bilateral maxillary canine-lateral incisor transposition.
Continuous workplace-based assessment as an indication of clinical competence in paediatric dentistry
(International Network for Higher Education in Africa, 2021) Mohamed, Nadia; Smit, Liezl
An authentic workplace setting provides the ideal opportunity for assessment of students’ clinical competence at the ‘does’ level of performance. Final-year dental students in the Department of Paediatric Dentistry at the University of the Western Cape are evaluated in the clinical environment on a daily basis through multiple clinical evaluations which assess clinical and diagnostic skills over a year. An additional end-of-module clinical assessment in the form of a single blinded patient case (BPC) determines if students have reached the expected level of clinical competence in terms of patient evaluation and diagnosis. However, the reliability and feasibility of this single end-of-module clinical case have been questioned in this setting. This study aimed to determine if the current continuous workplace-based assessment (WPBA) results could be used as an indication of final-year students’ clinical competence at the end of the module. A retrospective, quantitative, cross-sectional study was conducted of all complete assessment records. The correlation between the continuous WPBA components was analysed together with an evaluation of the reliability and validity of the assessment results. The continuous formative WPBA practices were found to be both valid and reliable when using Kane’s (2013) and Royal’s (2017) frameworks for analysis. However, the BPC should be reconsidered due to feasibility and reliability concerns. Key words: Dental education, Paediatric Dentistry, clinical skills, workplace, summative, formative, continuous assessment
Prevalence of oral mucosal lesions in human immunodeficiency virus-infected children attending the Pediatric Infectious Diseases Clinic in Cape Town
(Wiley, 2021) Mulder, Riaan; Mohamed, Nadia; Mathiba, Olorato
Objective: Investigation of the prevalence of oral mucosal lesions in human immuno-deficiency virus (HIV)-infected children undergoing highly active antiretroviral therapy (HAART).Materials and Methods: Cross-sectional study of 66 HIV seropositive children, comprised of 28 (42.4%) females and 38 (57.6%) males (average age of 6 years). Study participants all required data regarding CD4+ T-helper cell counts and the viral load. All participants underwent an orofacial clinical examination by calibrated clinicians. Associations between the presence of oral mucosal lesions, CD4+ cell counts, and viral load were analyzed using Poisson regression. Results: The prevalence of oral manifestations was detected in 21 children (31.8%).Oral lesions were detected in 16 children with viral load copies <50 cells/mm3and22 children with CD4+ counts >500 cells/mm3. Predominant lesions identified included angular cheilitis (36.7%), candidiasis (13.3%) and atypical oral ulcers (13.3%).The presence of one lesion was the most prevalent represented by 19 children. Oral lesions in relation to the CD4+ counts >500 resulted in; 14 children with one oral lesion, 5 with two lesions and 3 with three oral mucosal lesions. The other half of thisCD4+ count patient group presented with no oral mucosal lesions. Oral lesions in relation Viral load copies <50 resulted in; 9 children with one oral lesion, 3 with two oral mucosal lesions and 4 with three oral mucosal lesions. The other half of this Viral load patient group presented with no oral mucosal lesions. No significant correlations were established between the presence of oral mucosal lesions and low CD4+counts (p = 0.715) nor with high viral load counts (p = 0.638).Conclusion: HIV-related oral mucosal lesions still presented in the participants despite management with HAART. Based on the results, CD4+ counts and viral load does not appear to be suitable markers of orofacial involvement in children.
Allergic contact dermatitis from resin‑modified glass ionomers
(Wolters Kluwer, 2019) Buchanan, Glynn Dale; Tredoux, Sheree; Gamieldien, Mohamed Yasin
Monomers in a variety of dental materials may cause allergic contact dermatitis. While resin materials have been implicated in the onset of this condition, there is a paucity of evidence linking the condition to the resin‑modified glass ionomers (RMGIs). This report documents a rare case of a dentist who developed allergic contact dermatitis following exposure to a RMGI. Contact dermatitis occurred despite the use of latex gloves, which were worn during the procedure. Both the acute and chronic stages of the condition were clinically represented. Patch testing was conducted to confirm the diagnosis. A no‑touch technique and the routine use of nitrile gloves were subsequently adopted, which resulted in an overall decrease of the condition.Dentists, auxiliary personnel, and students should be aware of the possibility of sensitization to, and the development of allergic contact dermatitis not only from conventional resin materials, but also from the RMGIs.
The prediction of the size of unerupted canines and premolars in a contemporary orthodontic population
(1974-04) Tanaka, Marvin; Johnston, Lesley
Linear regression equations for the prediction of the mesiodistal widths of unerupted canines and premolars were calculated for a large sample of recent orthodontic patients. The form of the equations, as well as the size of the various confidence belts, were generally similar to those in the widely used but incompletely characterized Michigan Mixed Dentition Analysis. Although either set of tables would seem equally appropriate, a simple approximation— half the width of the mandibular incisors plus either 11.0 for the maxillary canine-premolar segments, or 10.5 for the mandibular segments— is of comparable accuracy. The
Determination of orthodontic bracket and tooth adaptation using an X-ray micro-computer tomography scanner
(Elsevier, 2020) Fakir, Yaseen; Keanly, Colm; Mulder, Riaan
The determination of the orthodontic brackets’ adaptation to the curvatures of teeth is a difficult topic to study. The complexity arise due to the different designs of their fitting surfaces, margins and curvatures of orthodontic brackets. Teeth on the other hand have variation in their curvatures and the question remains how well an orthodontic brackets truly adapt to the teeth. Previous methods from the literature determined the curvature of teeth through the superimposition of circular templates onto dental plaster models as well as the use of acrylic arcs of various diameters.
Oral status of HIV-infected children aged 12 years or younger who attended a Paediatric Infectious Diseases Clinic in Cape Town
(Wiley-Blackwell, 2020) Mohamed, Nadia; Mathiba, Olorato Patience; Mulder, Riaan
Children continue to suffer from the impact of the human immunodeficiency virus-acquired immunodeficiency syndrome (HIV/AIDS) pandemic. In Cape Town, these children receive medical care including antiretroviral therapy from facilities like Tygerberg Hospital's Paediatric Infectious Diseases Clinic. HIV-infected children may experience an increased caries experience when compared with their healthy peers
Biomaterials and designer functional applications in oral cavity
(Nova Science Publishers, 2016-05-10) Perchyonok, Tamara; Mulder, Riaan
Dental biomaterials and natural products represent two growing research fields, revealing that plant¬derived compounds may play a role not only as nutraceuticals in affecting oral health but also in improving physicochemical properties of biomaterials used in dentistry. Recently, the role of free radicals in healthcare has attracted tremendous interest in the field of medicine, dentistry and molecular biology. Free radicals can be either harmful or helpful to the human body. When there is an imbalance between input and output of free radicals, a condition called “oxidative stress” develops. To counteract oxidative stress, the body has protective antioxidant mechanisms, which aid in lowering the incidence of various human morbidities and mortalities.
A comparison of the dental age estimation methods of Phillips and Proffit in a sample of South African children
(The South African Dental Association, 2018) Elgamri, Alya; Mohamed, Nadia; Hudaon, Athol
Introduction: Dental age is an indicator of the physiological maturity of growing children. Different methods for estimating the dental age in contrast to the chronological age have been proposed. Aims and objectives: The aim of this retrospective study was to compare the accuracy of the Phillips and the Proffit methods in estimating the dental age in a mixed sample of South African children. Methods: A random selection was completed of 100 panoramic radiographs of patients with known chronological ages, ranging between 6 and 11 years. Dental age for each radlograph was esdmated using both the Phillips and the Proffit methods. Results: The Phillips method underestimated the age of combined sample by four months (statistically significant p =0.03}, whilst the age of the boys sample was underestimated by six months (statistically significant p <0.0001). For the girls' sample, the Proffit method underestimated the age by only two days (not statistically significant p =0.97). Proffit's method underestimated the age of the boys by two months (not statistically significant (P= 0.15). Conclusion: Even though It has not previously been validated, Proffit's description of dental development has been shown to be accurate in estimating the dental age.
South African statutory regulations for dental practices
(SADA, 2018) Mulder, Riaan; Mulder-van Staden, S
The Constitution of the Republic of South Africa dictates that: "every person has the right to a working environment that is not harmful to their health nor well-being". The practitioner and/or health care facility as the employer should ensure a safe working environment as far as reasonably possible for all employees, as well as individuals attending the facility. The Centres for Disease Control in the United States of America has a comprehensive document that outlines every aspect of infection prevention in the dental setting.

Browse

collection.page.browse.recent.head