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H Bernitz

Publications and source records attributed to H Bernitz.

9 recordsLinked to original sources
PubMed2006

A pilot study to determine the effects of skin contact on two commonly used dental impression materials.

Impression materials used in the analysis of bite marks are required to maintain their stability and integrity for extended periods. It has been observed that certain impressions taken of skin lose their properties with time, becoming sticky and unusable as evidence. The objective of this study was to investigate the onset of "stickiness" in two commonly used dental impression materials when brought into contact with skin. The two materials tested were Impregum and President. They were syringed into glass rings positioned on the upper arms of 28 volunteers. Changes in stickiness were monitored over a four-month period using a tensile testing machine. A metal plunger was lowered onto the impression material and then retracted measuring the adhesive force of the material to the lower surface of the plunger. Over the research period 17 of the 28 rings of Impregum became sticky and changed colour from purple to turquoise. The remaining 11 Impregum samples, all the President samples and all control samples remained unchanged over the 120 day period. The results of this study show that certain factors present in or on skin are responsible for the loss of surface integrity of Impregum. The factors responsible for these changes have not been established.

Adhesiveness↗
PubMed2005

Concepts to elucidate the pattern-associated analysis of tooth marks in court.

Increased awareness by crime scene detectives has led to a rise in number of bite mark associated cases appearing before the South African courts. This has led to an increased number of dentists being subpoenaed to give forensic evidence. The purpose of this paper was to elucidate the presentation of evidence in pattern associated tooth mark analysis. Three aspects are discussed. They are the basic principle of pattern association, the effects of limited shrinkage and distortion on the pattern of the tooth marks, and finally how to overcome the difficulties that court personnel experience in visualising bite marks. The author has applied these basic concepts over the past six years. Judges and defence advocates have been able to understand the simple concepts and apply them to the more complex issues before them. The concepts described should be familiar to all dentists and forensic odontologists giving tooth mark evidence in the high court. They will assist in explaining all aspects of pattern association to the legal fraternity and aid in the presentation of the evidence. Their strength is in their simplicity.

Bites, Human↗
PubMed2003

Bungled bite mark evidence collection: a proposed protocol for the prevention thereof.

In recent years, several bite mark cases referred to our department could not be adequately analysed due to poor evidence collection. This has highlighted the fact that police officers, forensic pathologists and dental practitioners do not have access to the information required to collect, record, duplicate, store and transport the relevant evidence correctly. This article highlights several case studies in which evidence collection was bungled. A protocol is proposed that should eliminate this problem.

Aged↗
PubMed2003

Retrospective investigation of dental records used in forensic identification cases.

The purpose of this paper was to investigate the standard of dental record keeping from a sample of forensic records retrieved from the Department of Oral Pathology and Oral Biology, School of Dentistry, University of Pretoria. Forty of the most recent cases in which ante-mortem information was required, were analysed. From the investigation it was clear that dentists did not comply with the requirements pertaining to dental charting and record keeping. A recommended code of abbreviations is proposed for use by dentists. It is concluded that until such time as charting is reinstituted as a legal requirement by the Health Professional Council of South Africa, dentists would not routinely chart their patients' dental status.

Dental Records↗
PubMed2002

Comparison microscope identification of a cheese bitemark: a case report.

Police investigating the murder of a farmer recovered a piece of cheese containing bite- marks. The local dental practitioner used white plaster to make casts of the bitemarks in the cheese and also of the teeth of three suspects. The cheese specimen was retained by the police and seven months later the case was referred to the Forensic Odontology Unit at the University of Pretoria where a silicone rubber cast of the bitemarks in the cheese was made. A lack of concordant features present in a conventional pattern-associated comparison was overcome with the aid of a Leica DMC comparison microscope. Individual features observed under 6.3x magnification aided in the positive identification of the suspect, who when confronted with the evidence, admitted guilt at his first court appearance.

Bites, Human↗
PubMed2000

Comparison of bitemarks left in foodstuffs with models of the suspects' dentitions as a means of identifying a perpetrator.

In a recent court case, a comparison was made between an impression of marks left in cheese at a murder scene and a set of study models of one of the suspects. The court was reluctant to accept the validity of the pattern-associated comparison that was used in the identification. This study compared marks made in cheese, butter and cooked potato with study models taken from volunteers. Pattern-associated comparison was the method used. Eighty pair-wise comparisons were made by two odontologists. The examiners correctly identified all the true matches from among the eighty comparisons as well as selecting the dental models for which there were no corresponding silicone impressions. In the absence of identifiable fingerprints or DNA samples, the method can be employed for matching left in foodstuffs to the dentitions of suspects.

Adolescent↗
PubMed1998

The prevalence of oral pathoses in a private dental practice: a 30 month survey.

The purpose of this study was to determine the prevalence of oral lesions in a private dental practice, which treats a broad spectrum of patients from both urban and rural areas. All oral lesions were documented over a 30 month period in a research programme, which formed part of the normal patient treatment plan. The lesions were analysed according to the prevalence of the lesions, race, age and gender distribution, and the ratio of lesions diagnosed by the practitioner compared with those presented for treatment by the patients. A total of 8418 patients were examined and 151 pathological lesions were diagnosed, representing 46 different conditions. The commonest conditions were fluorosis (11 per cent of lesions) and geographic tongue (11 per cent of lesions seen). Twenty conditions (47.8 per cent) were seen only once. The male:female ratio was 1.17:1. A total of 74 per cent of the lesions were seen in patients between the 2nd and the 5th decades and 25 per cent in the 4th decade. Patients seeking treatment suffered from conditions such as fluorosis causing aesthetic problems. On the other hand premalignant lesions such as leukoplakia and life threatening diseases were usually detected by the dentist, which stresses the importance of a thorough clinical examination of all patients. Fluorosis documented in 17 patients in this study, led to analysis of drinking water in the Dennilton area, which was found to contain toxic levels of fluoride.

Adolescent↗
PubMed1998

An inclusion technique for marking dentures.

The importance of placing identification markers in dentures is well documented and this paper describes a simple and inexpensive technique for doing it. Twenty marked upper acrylic simulated dentures and 20 controls (unlabelled) were constructed in a standardized mould. Clear laminated labels were produced in a P-touch 300 electronic lettering system and contained both the patient's identification number and suffix ZA (international code for South Africa). The markings were both clear and aesthetically acceptable. Strength tests were carried out to establish the effect of the mark with the result that no significant difference (p70.05) was demonstrated. The routine marking of all dentures by this method is advocated.

Acrylic Resins↗