Regurgitation erosion as a possible cause of tooth wear in ancient British populations

Root grooves on two adjacent anterior teeth of Australopithecus africanus

Tooth root grooves and other ante-mortem dental tissue loss, not associated with caries found on or near the cementoenamel junction (CEJ), are commonly termed non-carious cervical lesions. Three main processes are implicated in forming these lesions: abrasion, dental erosion, and abfraction. As yet, these lesions have not been described in non-Homo hominins. In this study, South African fossil hominin collections were examined for evidence of any type of non-carious cervical lesion. Only one individual shows ante-mortem root grooves consistent with non-carious cervical lesions. Two teeth, a mandibular right permanent lateral incisor (STW 270) and canine (STW 213), belonging to the same Australopithecus africanus individual, show clear ante-mortem grooves on the labial root surface. These lesions start below the CEJ, extend over a third of the way toward the apex, and taper to a point towards the lingual side. The characteristics of these grooves suggest the predominant aetiology was erosive wear. In addition, they are extremely similar to clinical examples of dental erosion. These are the oldest hominin examples of non-carious cervical lesions and the first described in a genus other than Homo. Further, the lesions suggest that this individual regularly processed and consumed acidic food items.

Oro-facial manifestations in patients with eating disorders

Studies have reported that the oral health status is jeopardized in patients with eating disorders. The aim was to review the oro-facial manifestations in patients with eating disorders. The address the focused question was "What is the oro-dental health status in patients with eating disorders?" MEDLINE/PubMed and Google Scholar databases were searched from 1948 to March 2012 using the following terms in various combinations: "Anorexia nervosa", "bulimia nervosa", "eating disorders", "dental", "oral health status". Letters to the editor, unpublished data and articles published in languages other than English were excluded. Dry lips, burning tongue and parotid gland swelling are common manifestations in patients with eating disorders as compared to medically healthy controls. The association of dental caries and periodontal disease in patients with eating disorders remains debatable. Temporomandibular disorders have also been reported to be more prevalent in patients with eating disorders as compared to healthy controls. A critical oral-dental examination during routine dental check-ups may reveal valuable information regarding the presence or absence of eating disorders in routine dental patients. This may be important information, updating the medical history, supporting the role of the physician.

Dental erosion and its growing importance in clinical practice: from past to present

Since the mid-1990s, the focus of studies on tooth wear has steadily shifted from the general condition towards the more specific area of dental erosion; equally, a shift has occurred from studies in adults to those in children and adolescents. During this time, understanding of the condition has increased greatly. This paper attempts to provide a critical overview of the development of this body of knowledge, from earlier perceptions to the present. It is accepted that dental erosion has a multifactorial background, in which individual and lifestyle factors have great significance. Notwithstanding methodological differences across studies, data from many countries confirm that dental erosion is common in children and young people, and that, when present, it progresses rapidly. That the condition, and its ramifications, warrants serious consideration in clinical dentistry, is clear. It is important for the oral healthcare team to be able to recognize its early signs and symptoms and to understand its pathogenesis. Preventive strategies are essential ingredients in the management of patients with dental erosion. When necessary, treatment aimed at correcting or improving its effects might best be of a minimally invasive nature. Still, there remains a need for further research to forge better understanding of the subject.

Rehabilitation of the worn dentition

The purpose of this review was to evaluate the literature on the rehabilitation of tooth wear, with some pertinent historical, epidemiological and aetiological aspects of tooth wear provided as background information. In historical skull material, extensive tooth wear, assumed to be the result of coarser diets, was found even in relatively young individuals. Such wear is seldom seen in current populations. Although many of the factors associated with extensive tooth wear in historical material are no longer present or prevalent, new risk factors have emerged. In the young individual, the literature points to a global rise in soft drink consumption as the most significant factor in the development of tooth wear through dental erosion. Among older individuals, lifestyle changes and chronic diseases that are controlled with medications that may, in turn, result in regurgitation and/or dry mouth, are possible reasons amongst others for the widespread clinical impression of an increasing prevalence of tooth wear. The aetiology of tooth wear is multifactorial and the role of bruxism is not known. Clinical controlled trials of restorative and prosthodontic approaches for the range of clinical conditions that wear can give rise to, are limited in number and quality. Equally, the striking lack of evidence regarding the long-term outcomes of treatment methods and materials calls for caution in clinical decision-making. Notwithstanding these observations, clinicians have provided and continue to provide rehabilitative strategies for managing their patients' worn dentitions that range traditionally from extensive prosthodontics to an increasing reliance on adhesive techniques.

How valid are current diagnostic criteria for dental erosion?

In principle, there is agreement about the clinical diagnostic criteria for dental erosion, basically defined as cupping and grooving of the occlusal/incisal surfaces, shallow defects on smooth surfaces located coronal from the enamel–cementum junction with an intact cervical enamel rim and restorations rising above the adjacent tooth surface. This lesion characteristic was established from clinical experience and from observations in a small group of subjects with known exposure to acids rather than from systematic research. Their prevalence is higher in risk groups for dental erosion compared to subjects not particularly exposed to acids, but analytical epidemiological studies on random or cluster samples often fail to find a relation between occurrence or severity of lesions and any aetiological factor. Besides other aspects, this finding might be due to lack of validity with respect to diagnostic criteria. In particular, cupping and grooving might be an effect of abrasion as well as of erosion and their value for the specific diagnosis of erosion must be doubted. Knowledge about the validity of current diagnostic criteria of different forms of tooth wear is incomplete, therefore further research is needed.

Associated postmortem dental findings as an aid to personal identification

The use of the unique features of the human dentition to aid in personal identification is well accepted within the forensic field. Indeed, despite advances in DNA and other identification methodologies, comparative dental identifications still play a major role in identifying the victims of violence, disaster or other misfortune. The classic comparative dental identification employs the use of postmortem and antemortem dental records (principally written notes and radiographs) to determine similarities and exclude discrepancies. In many cases the tentative identification of the individual is unknown and therefore antemortem records cannot be located. In such a situation a dental profile of the individual is developed to aid the search for the individual's identity. With such a profile a forensic odontologist can identify and report indicators for age at time of death, race (within the four major ethnic groups) and sex. In addition to these parameters the forensic dentist may be able to give more insight into the individual. This paper outlines, for the non-expert, some of the additional personal information that can be derived from the teeth of the deceased, and which may assist in their ultimate identification.

Characteristics of tooth wear in relation to different nutritional patterns including contemporary and medieval subjects

The present study sought to evaluate the characteristics of tooth wear in subjects with an acidic diet in relation to subjects with substantially different nutritional patterns. The evaluation included medieval skulls (group 1, n = 102, abrasive nutrition), study models of individuals living on an acidic diet (group 2, n = 100) and randomly selected subjects (group 3, n = 100, average Western diet). Wear was visually recorded on oral, vestibular and occlusal/incisal surfaces using quantitative and morphological criteria. The mean age was 42.3 +/- 15.3 yr in group 1, 40.9 +/- 11.2 yr in group 2 and 36.7 +/- 11.7 yr in group 3. Group 1 exhibited the most pronounced substance loss, followed by groups 2 and 3. On occlusal surfaces, cupping was common in group 1 followed by group 2, but was rare in group 3. An inverse relation was found for facets. On buccal surfaces, no substance loss was observed in group 1, whereas in group 2, 63% had at least one tooth with a buccal lesion compared to 8% in group 3. The occlusal substance loss observed in subjects exposed to acids may be interpreted as increased abrasion/demastication of acid-softened dental hard tissues. The occurrence of concavities on smooth surfaces appears to be significant for the diagnosis of dental erosion.

Dental erosion in deciduous teeth--an in vivo and in vitro study

OBJECTIVE

The aims of this study were to report on severe dental erosion and its associated etiological factors in deciduous teeth of Saudi children (n=16, X macro=6.5 years, R=5--8) in vivo, and to confirm (or reject) the clinical diagnosis by scanning electron microscopy (SEM). Another aim was to study progression of erosion in vitro using extracted healthy deciduous and permanent teeth.

METHOD

For the in vivo study, a questionnaire and clinical examination was completed, medical history obtained and exfoliated eroded teeth (n=8) examined by SEM. For the in vitro study, enamel specimens were prepared from Saudi (n=21) and Finnish (n=19) deciduous teeth as well as Finnish permanent teeth (n=20), immersed in 2% citric acid for 5--30 min, microhardness measurements performed, and the specimens studied by SEM.

RESULTS

The in vivo investigation showed that high intake of acidic drinks and fruits, upper respiratory tract problems and frequent medications may constitute possible etiological and/or aggravating factors for severe dental erosion in Saudi children. Deciduous tooth enamel was softer than permanent tooth enamel. SEM showed no clear differences in the ultrastructure of the enamel specimens amongst the three groups. The clinical diagnosis of severe dental erosion in those cases studied was reliable as verified by SEM.

CONCLUSIONS

The presence of dental erosion in children is likely to be associated with a number of general health and dietary factors but is also aggravated by the relatively more rapid progression of erosion in the deciduous teeth.

Eighteenth and nineteenth century dental restoration, treatment and consequences in a British nobleman

This paper examines unusual eighteenth and nineteenth century dental treatment and its consequences, in a nobleman excavated from beneath St. Nicholas' Church, Sevenoaks, Kent, UK in the early 1990s. This rare archaeological case exhibits erosion of dental enamel on the labial surface of all the anterior dentition. A programme of historical research suggests that this might be attributed to the application of an acid-based dental tincture or the use of an abrasive substance to whiten the teeth. Palliative treatment for the consequence of this application was prescribed by Dr Robert Blake of Dublin. Further, it bears witness to three dental restorations, two of gold and one tin. The two gold (foil) fillings are an occlusal in the upper-right second molar and a cervical on the labial surface of the upper left canine. The tin filling is an occlusal in the upper left second molar. Excavation of the carious tissue appears to have been undertaken using a spoon shaped implement.

Gingival recessions and noncarious cervical lesions: a soft and hard tissue challenge

Gingival recessions and noncarious cervical lesions are frequent and closely related defects which can be successfully treated by mucogingival surgery and restorative therapy techniques either used alone or in combination depending on the defect characteristics. Proper treatment planning is guided by careful clinical diagnosis. A selection of treatment modalities are presented and useful hints proposed: the long term success is always strictly bound to the identification and elimination of the etiologic factors, to a correct treatment and a meticulous maintenance program.

Dental erosion associated with soft-drink consumption in young Saudi men

This study reports on the causative factors of dental erosion in selected high- (n = 19) and low-erosion (n = 19) subgroups of a larger random sample (n = 95) of young male Saudi military inductees. By means of a questionnaire, the role of various possible factors related to oral health in general, and to dental erosion in particular, was assessed for each participant. Clinical examination included recordings of severity of dental erosion and fluorosis, presence of buccal cervical defects and first permanent molar 'cuppings', DMFT and DMFS, visible plaque index, and gingival bleeding index. In addition, bitewing radiographs, study casts, and intraoral color transparencies were obtained for each individual. Logistic regression analysis showed a strong correlation between the presence of dental erosion and a high level of consumption of cola-type soft drinks. Other statistically significant associated factors, although of less predictive strength, were type of cleaning aid and gingival bleeding index. In subgroup comparisons, dental problems (primarily pain), number of buccal cervical defects, and number of missing teeth were significantly greater in the high- than in the low-erosion subgroup.

The relationship between gastro-oesophageal reflux disease and dental erosion

It is well known that acid regurgitated from the stomach into the mouth will erode teeth. Conditions such as anorexia and bulimia nervosa, chronic alcoholism and gastric disturbances cause palatal dental erosion. The common factor in these conditions is the role played by the stomach and oesophagus in the acid movement. Acid moving through the lower oesophageal sphincter into the oesophagus is described as gastro-oesophageal reflux (GOR). In some patients the acid movement becomes chronic, painful and requires treatment and is termed gastro-oesophageal reflux disease (GORD). It is felt by many gastroenterologists that GORD is a failure of the anti-reflux mechanism, which is predominantly controlled by the lower oesophageal sphincter (LOS). Regurgitation is the reflux of gastric juice through the upper oesophageal sphincter and into the oral cavity. Once the acid has reached the mouth the potential exists for damage to the teeth. This paper reviews the role of GOR, GORD and regurgitation in the aetiology of dental erosion.

Methods of assessing erosion and erosive potential

Methods for use in vitro are reviewed first, classified under the examination of extracted teeth, chemical and physical methods, digital image analysis, scanning electron microscopy and other potentially useful techniques. Methods for recording erosion in laboratory animals are dealt with next, including techniques that can also be used in vitro, Restarski's system and various modifications of it, and digital image analysis. Thirdly the main systems and indices that have been designed for clinical use are arranged under case histories and clinical examination, scales of severity and indices of diagnosis of varying complexity. Finally, some of the main advantages and limitations of the techniques are summarized.

Prevalence of dental erosion and the implications for oral health

The literature on dental erosion is made up of a number of areas, some of which are reviewed here: there are anecdotal case reports, linking a small number of clinical cases with a possible etiological factor. The second area of evidence concentrates on case control studies in which there is a strong association with dental erosion, for example, patients with bulimia. The final piece of epidemiological evidence is beginning to emerge as prevalence studies, but the information from prevalence data worldwide is scanty. It is difficult to compare prevalence studies because of the different indices used in the various studies and also because of the different teeth assessed in the sample. Standardization of indices used would overcome some of these differences as would the reporting of results in a comparable way. However, identifying the true prevalence of erosion per se is fraught with difficulty because there may be more than one etiological factor operating and attrition and or abrasion may complicate the picture, especially in older populations. Case reports frequently associate evidence of erosion with excessive use of particular drinks or foodstuffs so they must be viewed with caution. There is an increasing awareness, amongst the dental profession, of the potential for this particular form of tooth wear to occur. It is important that the dental team is vigilant and instigates preventive measures before tooth tissue loss becomes clinically significant. The importance of erosion in dental health promotion should not be overlooked.