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Biomedical subjects

J A Kieser

Publications and source records attributed to J A Kieser.

At least 19 recordsLinked to original sources

Dental and maxillofacial injuries among older New Zealanders during the 1990s.

Not only is the number of older people increasing in New Zealand, but a greater number of them are keeping their own teeth, with predictable consequences for the costs of treating (and rehabilitating) dental and maxillofacial trauma in that group. The aim of the study was to describe the occurrence of dental and maxillofacial trauma involving New Zealanders aged 65 and over during the 1990s. The investigation was a secondary analysis of routinely collected, national-level compensation and hospital treatment data. The analysis showed that: (1) there was an increase in the rate and absolute number of injuries among older people; (2) the dental trauma rate was highest among males in the youngest age group, while the facial fracture rate was highest among older females; and (3) there was a general increase in the contribution of falls to the occurrence of trauma. Measures which aim to reduce the occurrence of falls among older people will also reduce the oral and maxillofacial trauma rate in that age group.

Accidental Falls↗

Risk indicators for tooth wear in New Zealand school children.

AIM: To investigate the prevalence and severity of tooth wear in the primary dentition of a representative sample of New Zealand school children and relate these to possible risk factors. DESIGN: A cross-sectional study. SETTING: Primary schools in Dunedin, New Zealand. PARTICIPANTS: 104 children of both sexes, aged between 5 and 8 years, randomly selected. METHODS: Clinical examinations of the buccal, occlusal/incisal and lingual surfaces of deciduous canines and molars. MAIN OUTCOME MEASURE: Degree of wear and the presence of dentinal cupping of teeth. Information on weaning and consumption of fruit-based drinks at bed time, frequency of consumption of fruits, yoghurt, pickled foods, fizzy and fruit-based drinks. RESULTS: The prevalence of tooth wear was similar in boys and girls and there were no significant differences between sides of the arches. A high percentage (82%) of children had at least one primary tooth with dentine exposed. While maxillary canines showed the greatest prevalence of dentine exposed, maxillary molars displayed the greatest prevalence of cupping. Severe tooth wear was less prevalent among children weaned after 12 months (14.3%) than those weaned earlier (27.9% P < 0.01). There were no statistically significant associations between wear and the consumption of fruit, yoghurt, pickled foods, fizzy drinks or fruit-based drinks. CONCLUSIONS: Tooth wear associated with dentine exposure is common in 5-8 year old children. This is not significantly associated with dietary factors, but appears to be related to early weaning from the breast.

Beverages↗

Weighing evidence: quantitative measures of the importance of bitemark evidence.

Quantitative measures of the importance of evidence such as the "likelihood ratio" have become increasingly popular in the courtroom. These measures have been used by expert witnesses formally to describe their certainty about a piece of evidence. These measures are commonly interpreted as the amount by which the evidence should revise the opinion of guilt, and thereby summarize the importance of a particular piece of evidence. Unlike DNA evidence, quantitative measures have not been widely used by forensic dentists to describe their certainty when testifying about bitemark evidence. There is, however, no inherent reason why they should not be used to evaluate bitemarks. The purpose of this paper is to describe the likelihood ratio as it might be applied to bitemark evidence. We use a simple bitemark example to define the likelihood ratio, its application, and interpretation. In particular we describe how the jury interprets the likelihood ratio from a Bayesian perspective when evaluating the impact of the evidence on the odds that the accused is guilty. We describe how the dentist would calculate the likelihood ratio based on frequentist interpretations. We also illustrate some of the limitations of the likelihood ratio, and show how those limitations apply to bitemark evidence. We conclude that the quality of bitemark evidence cannot be adequately summarized by the likelihood ratio, and argue that its application in this setting may be more misleading than helpful.

Bayes Theorem↗

Bite injuries: pathophysiology, forensic analysis, and management.

Bites are serious injuries that constitute 1 percent of all emergency-department visits in the United States of America. Human bite injuries may lead to loss of function, infection, and gross disfigurement, and often are associated with interpersonal and sexual violence, and child abuse. Issues with infection from oral contaminants, tissue damage, and difficult surgical reconstruction make the management of human bite injuries a challenge. The unique nature of teeth and the bite marks they produce are invaluable in forensic pathology. A systematic and detailed evaluation of bite injuries should be performed by a forensic odontologist in order to provide the necessary information for forensic purposes. Management of human bite injuries includes wound debridement, surgery to repair or replace damaged tissue, and long-term antibiotic therapy.

Age Distribution↗

Dental misidentification on the basis of presumed unique features.

Positive identification of skeletal remains by dental comparison depends on the demonstrable concordance between postmortem and antemortem records. However, there is no accepted norm for the number of points of concordance and there are circumstances when a single (or a few) unique features may allow positive identification. We present a recent case in which superficial similarity may have led to misidentification. We argue that misidentification is particularly likely with over-reliance on apparently unique features. The fact that a single inexplicable inconsistency will rule out a positive dental identification is highlighted.

Adult↗

Anatomical knowledge and clinical evaluation of the muscles of mastication.

In this survey, we identify the positive role that an instructional anatomy course has prior to a workshop on temporomandibular dysfunction. Not only did it result in enhanced clinical evaluation of the muscles of mastication acquired by the participants, but it also approximated the skills of dental and medical practitioners.

Anatomy↗

Root canal anatomy of anterior and premolar teeth in Down's syndrome.

AIM: The aim of this study was to examine tooth length and root canal anatomy of 281 anterior and premolar teeth from 66 DS individuals using a standard protocol. RESULTS: The results indicated that root canals in DS are relatively simple and that there is a significant reduction in root and crown length. CONCLUSIONS: We propose that these observations are commensurate with the suggestion that trisomy 21 exerts its effect by slowing the mitotic cycle and rate of cell proliferation, resulting in generalized retardation of growth.

Adolescent↗

Odontological identification in two high-impact, high-temperature accidents.

Here we report on two high-impact accidents both of which were complicated by fire. The first accident involved a light aircraft which crashed in a gorge while performing a low, slow flight. Both victims were found to have experienced extensive dental fracturing. The second accident was a high speed motor vehicle crash followed by incineration which left the two victims without dental fracturing. In the absence of comparative data on the effect of burning on teeth the cause of the foregoing remains unanswered.

Accidents, Aviation↗

Relationship between juvenile bruxing and craniomandibular dysfunction.

A longitudinal study was conducted over 5 years to investigate the relationship between juvenile bruxing and craniomandibular disorders. A total of 150 bruxers between the ages of 6 and 9 years were examined for oral parafunctions and TMJ symptoms. Of these, 126 were re-examined for the same signs and symptoms after 5 years. The results showed that only 17 individuals had retained their bruxing habit. In common with other studies, we found that symptoms reduced with age. It was concluded that juvenile bruxing was a self-limiting condition which does not progress to adult bruxism and which appeared to be unrelated to TMJ symptoms.

Aging↗

Dental asymmetry, maternal obesity, and smoking.

This study examines the levels of fluctuating dental asymmetry in four samples of school children: those whose mothers were obese and had smoked during the pregnancy concerned (n = 111); those whose mothers were obese non-smokers (n = 114); those whose mothers were non-obese smokers (n = 104); and those whose mothers were lean non-smokers (n = 111). The degree of fluctuating asymmetry was assessed by means of a rescaled asymmetry measure. Obesity was defined as Quetelet's index in excess of 30, and smoking status as at least 20 cigarettes per day during the pregnancy concerned. When the magnitudes of fluctuating asymmetry in children of lean smokers were compared to the control group of lean non-smokers, no significant univariate differences were found. Children of obese mothers, whether these smoked or not, were found to have significantly raised levels of asymmetry. An analysis of variance confirmed that the combination of obesity and maternal smoking was a significant predictor of fluctuating dental asymmetry. The teeth involved tended to be the maxillary first incisor and molars. It is concluded that maternal obesity has a destabilizing effect on the developing fetus and that this effect appears to be enhanced in obese mothers who smoked. This effect was absent in lean mothers, irrespective of their smoking status.

Adolescent↗

Basicranial flexion, facial reduction and temporomandibular joint dysfunction.

Although dysfunction is the major condition affecting the bilateral temporomandibular joint (TMJ), it has defied previous attempts to explain, predict, or prevent its clinical manifestations. A hypothesis is developed that there is an anatomical predisposition to TMJ dysfunction which should be sought in the phylogenetic flexing of the hominid basicranium. It is argued that the glenoid fossa, caught between an ever-increasing brain size and more ventrally oriented facial apparatus, has become deepened and hence labile to dysfunction.

Animals↗

Delayed tooth formation in children exposed to tobacco smoke.

Panoramic radiographs of 203 Caucasoid children between the ages of seven and ten years were examined for an evaluation of dental development. Four groups were studied: a control group in which neither parent had smoked during the pregnancy concerned, a group exposed to tobacco smoke from the mother only, a group exposed to smoke from the father only, and finally a group exposed to tobacco smoke from both parents. In each case, the dental age (determined according to the method of Moorrees) was contrasted to the chronological age of the subject. Overall results showed that there were no differences in dental ages related to gender. Maximum differences between chronological and dental ages were found in children subjected to cigarette smoke from both parents. Here, a 35% reduction in dental maturation was noted. Most affected teeth were the maxillary second premolars, while the central incisors were the least affected.

Child↗

Inequalities in the pattern of dental delivery in South Africa.

The pattern of dental delivery of three groups of private general practitioners were evaluated. The first group consisted of dentists who charged fees based on the National Schedule of the Dental Association of South Africa, the second charged fees at the recommended Scale of Benefit and served an urban population, while the last group served township dwellers at the Scale of Benefits. In each case, sequential claims of 500 medical scheme members were evaluated for ten randomly selected dentists within each group. Uni- and multivariate analyses revealed significant differences between these groups which centred on the use of cast restorations, bleaching of vital teeth and treatment of diseases of the oral mucosa. Because these differences do not conform to documented differences in dental needs between the two groups, it is concluded that other non-clinical factors influence the delivery of private dentistry.

Analysis of Variance↗

Sex allocation of skeletal material by analysis of the proximal tibia.

In this study we contrasted the confidence with which individuals may be grouped and then reallocated on the basis of a set of measurements from the proximal tibia. The data were derived from 100 Caucasoid (50 male) and 102 Negro (50 male) tibia housed in the R.A. Dart Collection. Multivariate discrimination was effected by means of canonical and stepwise discriminant analyses, whilst probabalistic models were used to allocate individuals. High levels of correct classification (84.62-92%) were matched by high levels of reallocation, suggesting that, in contrast to dental or craniobasal measurements, those of the proximal tibia may be usefully employed to allocate an individual on the basis of sex.

Black People↗

Mandibulodental allometry in the African wild dog, Lycaon pictus.

Mandibulodental relations were evaluated in a sample of 34 adult Lycaon pictus crania (18 males, 16 females). Standard mesiodistal and buccolingual measurements, together with 8 mandibular measurements (intercondylar distance, intercarnassial breadth, mandibular length, arch length, condylar height, canine-condylar length, mandibular width, mandibular height) were allometrically scaled to total skull length. These results were then compared with those of domestic dogs and of 3 smaller southern African canids, Vulpes chama, Canis adustus and C. mesomelas. The results highlighted the differences in mandibulodental relations between males and females and provided support for the theory that females have relatively larger postcanine tooth sizes to match the higher masticatory demands of lactation and pregnancy. The African wild dog is shown to be more closely related dentally to the domestic dog than has previously been supposed.

Animals↗

Comparative morphology of the mandibulodental complex in wild and domestic canids.

The relationships between mandibular and dental measurements were investigated in a sample of 60 adult domestic dogs, 17 black-backed jackals Canis mesomelas, 18 side-striped jackals C. adustus and 16 Cape foxes Vulpes chama. Standard mesiodistal and buccolingual tooth measurements, together with 8 mandibular measurements (intercondylar distance, intercarnassial breadth, mandibular length, arch length, condylar height, canine-condylar length, mandibular width, mandibular height) were scaled allometrically to total skull length. Despite wide differences in diet and sexual dimorphism between the 3 wild canid species, larger canids were found to be scaled up versions of smaller canids. While males showed a highly concordant patterning when compared with domestic dogs of equivalent size, females showed a remarkably mosaic pattern. Relative to skull size, the only teeth that appear to be larger than those of equivalently sized domestic dogs were the second molars. It is suggested that those theories of sexual dimorphism and functional integration which apply to skeletodental dimensions in primates may not be applicable to canids.

Animals↗