Genetic influence on the prevalence of torus palatinus

Prevalence of Oral Exostoses in Northern China During the Past Six Millennia-From a Sex and Age Perspective

This study is intended to investigate oral exostoses of 5 sample populations, spanning over 6000 years, from the same region of Northern China, to determine the significance of sex and age on the development of oral exostoses during each time period. The samples analyzed were 306 dry jaws from human skeletons, which were excavated from 4 archeological sites: Banpo (6700-5600 y BP), Shaolingyuan (3000 y BP), Shanren (2200 y BP), and Chang'an (1000-1300 y BP), as well as the modern Xi'an district. The sex and the age of the samples at death were estimated. The degree of buccal exostosis (BE), torus mandibularis (TM), and torus palatinus (TP) and the TP shape were recorded. The results showed BEs in the Banpo and Chang'an regions, TMs in the Banpo region were more often diagnosed in males than in females. Conversely, females in Shaolingyuan showed a higher prevalence and severity of TM than that in males. The occurrence of BEs in the Shanren and Xi'an regions, TMs in the Banpo, Chang'an, and Xi'an regions, as well as TPs in the Banpo region significantly increased with age at death. In conclusion, sex differences and increasing trends with age in relation to oral exostoses were found in samples from Northern China during the past six millennia.

Torus Mandibularis in Patients Receiving Hemodialysis

Reports on the prevalence of torus mandibularis among dialysis patients have been limited and inconclusive. A wide variety of oral manifestations has been found in patients with hyperparathyroidism. Furthermore, uremia-related changes in facial bone structures have been described in the literature. This prospective observational study examined 322 hemodialysis patients treated at the Chang Gung Memorial Hospital from 1 August to 31 December 2016. Two subgroups were identified: patients with torus mandibularis (n = 25) and those without (n = 297). Clinical oral examinations including inspection and palpation were employed. Our study found that most mandibular tori were symmetric (84.0%), nodular (96.0%), less than 2 cm in size (96.0%), and located in the premolar area (92.0%). Poor oral hygiene was observed among these patients, with 49.7% and 24.5% scoring 3 and 4, respectively, on the Quigley-Hein plaque index. More than half (55.0%) of patients lost their first molars. Multivariate logistic regression analysis revealed that blood phosphate level (odds ratio = 1.494, p = 0.029) and younger age (odds ratio = 0.954, p = 0.009) correlated significantly with torus mandibularis. The prevalence of torus mandibularis in patients receiving hemodialysis in this study was 7.8%. Younger age and a higher blood phosphate level were predictors for torus mandibularis in these patients.

Genome-wide family-based study in torus palatinus affected individuals

OBJECTIVE

Tori or exostoses are bony growths that appear in different oral regions. Torus palatinus, more specifically, develop in the palate midline and can impair proper word pronunciation and hinder the fabrication and use of dentures. Even though a multifactorial inheritance model has been suggested for torus palatinus appearance, precise genetic factors involved in its etiology remain unclear. Hence, in this study we aimed to identify variants across the genome of individuals from 46 Filipino families that associate with torus palatinus.

DESIGN

All families were composed of fishermen or landless rural dwellers who provided blood samples for DNA extraction and genotyping. A total of 3519 single nucleotide polymorphisms (SNPs) were analyzed through a transmission disequilibrium test in individuals affected by torus palatinus and their unaffected family members.

RESULTS

Fourteen SNPs showed trends for associations to the level of p < .005 threshold and several others were nominally (p < .05) associated with torus palatinus. We highlight SNP rs6582285, which is located in the CAPS2 gene, being the C allele less transmitted than the T allele in our sample. The C allele of CAPS2 rs6582285 protects from having torus palatinus whereas the other associations found were linked to an increased risk of developing the condition.

CONCLUSIONS

Trends for associations were identified for several markers across the genome, supporting the hypothesis that torus palatinus has a multifactorial mode of inheritance. We hope that our study contributes to a better understanding of torus palatinus etiology and helps guide future research in examining genes for this often-overlooked condition in different populations.

Mandibular tori interfering with the mobility of the lingual frenulum: a short case report

Introduction: Tori are benign hamartoma-like bone excrescences, usually asymptomatic. Their removal should not be systematic. Observation: A 62-year-old patient showed bilateral tori only leaving a 1.5 mm space for the lingual frenulum path between them. The direct functional consequence was a frequent blockage of the salivary caruncles below the tori. Tori resection was performed under local anaesthesia. Surgical outcome was simple with conventional analgesic treatment and oral care. Comfort and function were immediately restored. Discussion: The originality of this case does not lie in the nature of the lesions but in the uncommon size of their hypertrophy, which caused a lingual functional impairment. We have not found a similar case described in the literature.

Prevalence of Torus Palatinus and association with dental arch shape in a multi-ethnic cohort

Objectives: Torus Palatinus (TP) is a bony projection located on the oral surface of the hard palate. The trait is typically benign, has an unknown etiology, and varies widely in phenotypic expression. Prior studies suggest differences in TP prevalence by sex and ancestry, but the reported rates vary, even within a single ancestral group. We assessed the prevalence of TP and its association with palatal shape in a large multi-ethnic cohort of normal individuals. Methodology: 1102 adults were included (625 with European ancestry, 377 with West African anscestry, and 100 with East Asian ancestry). 3D digital dental casts were obtained and rated. TP frequencies were compared between sexes and/or ethnicities using Chi-squared tests. Dental cast models were then landmarked, and canonical variates analysis was performed to test for shape differences between those with and without TP. Results: Females had a significantly higher rate of TP than males across all three ancestral groups (p≤0.004). In males, no significant differences were found among ethnicities. Ancestral differences in TP frequency were driven by females, with East Asians having the highest rate (34.69%), followed by Europeans (24.88%) and West Africans (15.22%). Shape differences were found only in Asians and Africans, indicated a shorter and wider palate in presence of TP. Conclusions: Ethnic differences in TP frequency were present only in females. Further, females have considerably higher rates of TP than males in each population tested. Further studies of TP at earlier time-points and in connection to other aspects of craniofacial growth may shed light on these sex and ethnic differences.

Correlations between dental wear and oral cavity characteristics: Mandibular torus, palatine torus, and oral exostoses

OBJECTIVE

This study evaluates the correlations amongst mandibular torus, palatine torus, oral exostoses to dental wear/loss and temporomandibular damage.

METHODS

The sample consists of 504 skulls from the Hamann-Todd Osteological Collection; 223 African American and 281 European Americans aged between 30 and 80 years. The sample was analyzed using Pearson's Chi-square for significance of sex, age, ancestry, and wear as well as the interactions between the demographic variables and the presence of mandibular torus, palatine torus and oral exostoses.

RESULTS

Wear was statistically significant by age and sex but not ancestry. The maxillary exostoses varied significantly by age, ancestry and wear but not sex. Mandibular torus frequencies varied significantly by wear, sex and ancestry. The palatine torus varied significantly across wear groups, sex and ancestry.

DISCUSSION

The etiology of nonmetric oral cavity characteristics, mandibular torus, palatine torus and oral exostosis, is complex. The degree to which traits' presence and expression is the result of genetic and environmental interactions is not fully understood. More than age, sex or ancestry, the degree of dental wear and tooth loss influences the presence and expression of the oral cavity traits. The sample can be characterized as the presence of exostoses in higher frequencies in young African American males with little tooth loss. Males of both ancestral groups with heavy wear have higher frequencies of mandibular tori than females. The palatine torus is more common in edentulous European American females.

Torus Palatinus in Taiwan Patients Receiving Peritoneal Dialysis and Hemodialysis: A Prospective Observational Study

Purpose

A consensus about the pathogenesis of torus palatinus (TP) in patients receiving dialysis still eludes the scientific community. This prospective observational study investigated the epidemiology of TP in peritoneal dialysis and hemodialysis patients and analyzed the influences of multiple pathogenic factors such as mineral and bone disorders, genetic, environmental or nutritional triggers, progression of age, heredity, climatologic or biomechanical causes, and hyperparathyroidism on the formation of TP.

Methods

Between 2013 and 2016, a total of 575 chronic dialysis patients (441 on hemodialysis and 134 on peritoneal dialysis) were recruited from Chang Gung Memorial Hospital, Taiwan. Patients were stratified into two groups based on the presence (n = 179) or absence (n = 396) of TP. Demographic, oral examination, laboratory, and dialysis data were collected for analysis. Student’s t-test was used to analyze the quantitative variables and Chi-square or Fisher’s exact test for categorical variables. Univariate binary logistic regression analysis was conducted to determine the predictors for TP and multivariate binary logistic regression analysis to identify significant associated factors.

Results

The prevalence of TP in dialysis patients in this study was 31.1% (28.3% for hemodialysis and 40.3% for peritoneal dialysis). Patients with TP were younger (54.6 ± 13.4 versus 58.9 ± 14.7 years, P = 0.001) and mostly female (60.3 versus 41.2%, P < 0.001). Most TP cases (55.3%) were small in size (<2 cm), with the flat shape (56.4%) being the most common followed by the spindle (17.9%), nodular (17.3%), and lobular (8.4%) shapes. A longer duration of dialysis was associated with TP ≥2 cm than with TP <2 cm (94.4 ± 85.9 versus 72.8 ± 59.1 months, P = 0.048). Multivariate logistic regression revealed that female gender (odds ratio 2.108, 95% confidence interval 1.455–3.055, P < 0.001) and younger age (odds ratio 0.982; 95% confidence interval 0.969–0.994, P = 0.005) were significant predictors for TP.

Conclusion

The prevalence of TP in chronic dialysis patients is 31.1%, higher in patients receiving peritoneal dialysis (40.3%) than hemodialysis (28.3%). Female gender and younger age are significant predictors associated with TP.

The use of torus palatinus in the identification of unknown skeletal remains

Torus palatinus (TP) is a benign, bony outgrowth located on the hard palate. Variation in this trait occurs, ranging from absent to a protuberance several millimeters in length. If a TP becomes too large, it can interfere with daily activities and thus warrant medical attention. This case utilised the unique morphology of a TP after surgical invention to identify the unknown skeletal remains of a woman missing for six years. Even though there is still much unknown regarding the aetiology, occurrence and prevalence of TP, this study demonstrates the usefulness of anatomical variants in the identification of unknown skeletal remains.

Do Exostoses Correlate with Contact Disfunctions? A Case Study of a Maxillary Exostosis

A maxillary exostosis is a benign overgrowth of bone that occurs on the outer or facial surface of the maxilla and is usually located near the premolar or molar teeth. This paper investigates the correlation between the presence and growth of jaw exostoses and the oral mechanics of contact. For this purpose, a case study of an upper jawbone exostosis of a female patient was considered. 3D models of the patient’s cranial bones were extracted from 2D computerized tomography (CT) data and were analyzed by proper software. A contact congruence evaluation based on the Winkler contact model was performed, and results were presented in terms of indentation maps and load distributions. Results were correlated with the theory of bone remodelling by Wolff.

Survey of Torus Palatinus in Patients with End-Stage Renal Disease Undergoing Hemodialysis

Introduction

This study attempted to survey the oral findings of hemodialysis patients and analyze the prevalence and predictors for torus palatinus (TP) in this patient population.

Methods

A total of 322 hemodialysis patients were recruited. Patients were organized into two groups, based on the presence (n=93) or absence (n=229) of TP. Demographic, laboratory, and dialysis-related data were obtained for analysis.

Results

The prevalence of TP was 28.9% in this study. Patients with TP were younger in age [57.8±10.0 (37.4-86.9) versus 62.4±12.3 (25.0-87.8) years old; P=0.001] and predominantly female (60.2% versus 38.0%; P<0.001), compared to patients without TP. All TPs (100.0%) were symmetrical and located along the midpalatal suture. Most TPs were flat-shaped (55.9%) and near premolars (78.5%). The blood tests revealed higher blood concentrations of phosphate (5.4±1.1 versus 4.9±1.1 mg/dL; P=0.001) and lower blood concentrations of bicarbonate (20.9±2.4 versus 22.0±2.3 mmol/L; P<0.001) in patients with TP. Multivariate regression modeling showed that younger age [odds ratio (OR) 0.968; 95% confidence interval (CI) 0.939–0.982; P<0.001], female gender (OR 2.305; 95% CI 1.374–3.867; P=0.002), higher blood concentration of phosphate (OR 1.411; 95% CI 1.110–1.794; P=0.005), and lower blood concentration of bicarbonate (OR 0.868; 95% CI 0.791–0.994; P=0.040) were significant predictors for TP.

Conclusion

The prevalence of TP is 28.9%, and the majority of patients suffering TP are female. Younger age, female gender, elevated blood concentration of phosphate, and lower blood concentration of bicarbonate are predictors for TP.

The prevalence of antral exostoses in the maxillary sinuses, evaluated by cone-beam computed tomography

Background/purpose

Exostoses are outgrowths of normal compact and cancellous bone and may occur in different locations of the jaw. Exostoses are a rare anatomic variation in the maxillary sinuses. The purpose of this study was to investigate retrospectively the prevalence of location, size, shape, and symmetry of exostoses in the maxillary sinus, and to assess the relationship between demographic variables (i.e., age and sex) via cone-beam computed tomography images.

Materials and methods

Cone-beam computed tomography images of 1000 patients [521 (52.1%) females and 479 (47.9%) males], aged 10–85 years (mean age, 44 years), were examined. Two investigators examined the exostoses for location (i.e., inferior wall, medial wall, lateral wall, or posterior wall of the maxillary sinuses), size, shape (i.e., broad-based or mushroom-like), and symmetry (i.e., unilateral or bilateral). The age of the patients was categorized into three groups: 10–30 years, 31–50 years, and 51+ years. The data were statistically analyzed by using chi-square test, Fisher's exact test, and the t test.

Results

In total, 52 exostoses from 48 patients (4.8%) were identified. Exostoses were more common in females (n = 28, 58.3%) than in males (n = 20, 41.7%); however, there was no statistically significant difference between the sexes (P > 0.05). The presence of exostoses was very similar for all age groups with no statistically significant differences (P > 0.05).

Conclusion

Most exostoses were unilateral and on the inferior wall of the maxillary sinus. No statistically significant difference existed between the frequency and location of exostoses for sex or age groups (P > 0.05).

Oral Tori in Chronic Peritoneal Dialysis Patients

Background

The pathogenesis of oral tori has long been debated and is thought to be the product of both genetic and environmental factors, including occlusal forces. Another proposed mechanism for oral tori is the combination of biomechanical forces, particularly in the oral cavity, combined with cortical bone loss and trabecular expansion, as one might see in the early stages of primary hyperparathyroidism. This study investigated the epidemiology of torus palatinus (TP) and torus mandibularis (TM) in peritoneal dialysis patients, and analyzed the influences of hyperparathyroidism on the formation of oral tori.

Method

In total, 134 peritoneal dialysis patients were recruited between July 1 and December 31, 2015 for dental examinations for this study. Patients were categorized into two subgroups based on the presence or absence of oral tori. Demographic, hematological, biochemical, and dialysis-related data were obtained for analysis.

Results

The prevalence of oral tori in our sample group was high at 42.5% (57 of 134), and most patients with oral tori were female (61.4%). The most common location of tori was TP (80.7%), followed by TP and TM (14.0%), then TM (5.3%). All 54 TP cases were at the midline, and most were <2 cm (59.3%), flat (53.7%), and located in the premolar region (40.7%). Of the 11 TM cases, all were bilateral and symmetric, mostly <2 cm (81.9%), lobular (45.4%), and located at premolar region (63.6%). Interestingly, patients with oral tori had slightly lower serum levels of intact parathyroid hormones than those without oral tori, but the difference was not statistically significant (317.3±292.0 versus 430.1±492.6 pg/mL, P = 0.126). In addition, patients with oral tori did not differ from patients without tori in inflammatory variables such as serum high sensitivity C-reactive protein levels (6.6±8.2 versus 10.3±20.2 mg/L, P = 0.147) or nutritional variables such as serum albumin levels (3.79±0.38 versus 3.77±0.45 g/dL, P = 0.790). Furthermore, there were no differences between patients with and without oral tori in dialysis adequacy (weekly Kt/V_urea, 2.14±0.39 versus 2.11±0.33, P = 0.533; weekly creatinine clearance rate, 59.31±17.58 versus 58.57±13.20 L/1.73 m², P = 0.781), or peritoneal membrane transporter characteristics (P = 0.098).

Conclusion

Secondary hyperparathyroidism does not contribute to the formation of tori in peritoneal dialysis patients. Further studies are warranted.

Surgical management of the bilateral maxillary buccal exostosis

Buccal exostosis is benign, broad-based surface masses of the outer or facial aspect of the maxilla and less commonly, the mandible. They begin to develop in early adulthood and may very slowly enlarge over the years. A 24-year-old female presented with gingival enlargement on the buccal aspect of both the quadrants of the maxillary arch. The overgrowth was a cosmetic problem for the patient. The etiology of the overgrowth remains unclear though the provisional diagnosis indicates toward a bony enlargement, which was confirmed with the help of transgingival probing. The bony enlargement was treated with resective osseous surgery. The following paper presents a rare case of the bilateral maxillary buccal exostosis and its successful management.

Oral tori in chronic hemodialysis patients

BACKGROUND

This study investigated the epidemiology of torus palatinus (TP) and torus mandibularis (TM) in hemodialysis patients and analyzed the influences of hyperparathyroidism on the formation of oral tori.

METHOD

During 2013, 119 hemodialysis patients were recruited for dental examinations for this study.

RESULTS

The prevalence of oral tori in our sample group was high at 33.6% (40 of 119). The most common location of tori was TP (70.0%), followed by TM (20.0%), and then both TP and TM (10.0%). Of the 40 tori cases, most (67.5%) were <2 cm in size; moreover, the majority (52.5%) were flat in shape. In symmetry, most (70.0%) occurred in the midline, followed by bilateral sides (20.0%). Notably, the levels of intact parathyroid hormone did not differ in patients with or without tori (P = 0.611). Furthermore, patients with tori did not differ from patients without tori in inflammatory variables such as log high-sensitivity C-reactive protein (P = 1.000) or nutritional variables such as albumin (P = 0.247). Finally, there were no differences between patients with and without tori in adequacy of dialysis (P = 0.577).

CONCLUSIONS

Neither hyperparathyroidism nor inflammation malnutrition syndrome was found to contribute to the formation of oral tori in chronic hemodialysis patients. Further studies are warranted.

Prevalence and clinical characteristics of oral tori among outpatients in Northern Malaysia

OBJECTIVES

The objectives of this study were to determine the prevalence and clinical characteristics of torus palatinus (TP) and torus mandibularis (TM) in Malaysian dental patients.

METHODS

Thousand five hundred and thirty-two dental patients were examined for the presence of oral tori at the Faculty of Dentistry outpatient clinic, AIMST University. Factors such as race, age, sex, size, and shape of tori were studied.

RESULTS

The prevalence rates were 12% for TP and 2.8% for TM. A variation in the presence of tori among the three races in Malaysia-Chinese, Malays, and Indians-was noted, where the Chinese significantly had a higher prevalence of TP (17.9%) and TM (4.6%). Predominantly, tori were observed >40 years and older age group, and further both TP and TM were seen more commonly in women. Most TP were of smooth type (52.2%) and >2 cm (67.4%), while all TM were bilateral and nodular, plus most were <2 cm (67.4%).

CONCLUSION

Presence of tori (TP and TM) was detected in 12.5% of the participants. The variations noted in the prevalence and clinical characteristics of tori among people of different races living in the same country reflect its multifactorial etiology. Both genetic and environmental factors are responsible for its occurrence, and particular races are more prone genetically where its expression is enhanced by environmental factors.

Surgical management of palatine Torus - case series

INTRODUCTION: Torus palatinus is a specific name to identify exostoses developed in the hard palate along the median palatine suture. Despite of not being a pathological condition, its presence requires attention and knowledge regarding its management. Surgical removal of exostoses is indicated when the patient frequently traumatizes the area of palatine torus during mastication and speech or when it is necessary for the rehabilitation of the upper arcade with complete dentures. OBJECTIVE: The aim of this article is to present three cases of Torus palatinus and to discuss the management of them. CASE REPORT: In the first case, a 57-year-old Caucasian man sought oral rehabilitation of his edentulous maxilla but presented a hard nodules in the hard palate; in the second case, a 40-year-old Caucasian woman was referred for frequent trauma of palatal mucosa during mastication, aesthetic complaint, and discomfort caused by the trauma of her tongue in this area; and in the third case, a 45-year-old Caucasian woman presented with a lesion on the palate that caused difficulty swallowing. When the Torus palatinus was impairing the basic physiological functions of the patients, all cases were surgically treated, improving the patients' quality of life. FINAL CONSIDERATION: The dentist should be properly prepared to choose the best from among the existing surgical approaches for each individual lesion in order to improve the results and avoid possible complications.

Clinical, tomographic aspects and relevance of torus palatinus: case report of two sisters

Despite the nomenclature suggested to be a tumor, torus palatinus (TP) is an overgrowth of the bone in the palatal region and represents an anatomic variation. Its prevalence varies among the population studied and its etiology is still unclear; however, it seems to be a multifactorial disorder with genetics and environmental involvement. Surgical removal of the TP is indicated in the following circumstances: (1) deglutition and speech impairment, (2) cancer phobia, (3) traumatized mucosa over the torus, and (4) prosthetic reasons. The aim of this case report is describe cases that occurred in two sisters, emphasizing the genetic etiology of this anatomic variation. In addition, intra-oral exam and computed tomography scan (axial, coronal and sagittal view) provided a detailed assessment of the TP and elimination of other possible diagnoses, furthermore allowed a better analyzes of the anatomic relation with adjacentes structures. No surgical removal was indicated for both cases.

Guided surgery in unusual palatal torus

Palatine torus is a benign congenital outgrowth of bone that affects the hard palate and palatine processes, resulting from the "overworking" of osteoblasts and bone deposition along the line of the palatine fusion. Surgical excision is the only treatment for torus, and such patients are susceptible to intraoperative and postoperative complications of a traumatic, functional, or infectious nature. This article describes an atypical case of torus palatinus measuring 20.31 × 27.25 × 59.20 mm, which is the largest size ever described in the literature. This case required the use of a surgical guide in the intraoperative phase, with viable use in the postoperative phase as well. This guide proved versatile in reducing the risk of undercorrection and complications, offering greater patient comfort.

Prevalence of torus palatinus among a group of Japanese elderly

The purpose of this study was to examine the prevalence of torus palatinus (TP) among Japanese elderly and to identify the factors associated with the formation of TP. The subjects were adults aged over 60, who lived independently in the community and attended lectures once a week at the Senior Citizens' College in Osaka prefecture during 2007 and 2008. A total of 664 subjects, including 294 men and 370 women, were examined, and the mean age was 66·5±4·2 (s.d.). After informed consent was obtained, participants responded to a questionnaire and underwent clinical examination consisting of dental status, temporomandibular symptoms and occlusal force. There were 113 (17·0%) subjects with TP. The prevalence of TP was more frequent in women than in men (24·6% versus 7·5%, P<0·01). Moreover, there was a significant relationship between the presence of TP and the presence of Torus mandibularis (13·3% versus 25·9%). There was no significant relationship between the prevalence of TP and other factors; diurnal and nocturnal bruxism, occlusal force, occlusal support and temporomandibular diseases symptom. Logistic regression analysis, in which adjustment was made for age and occlusal force, revealed a significant relationship between the presence of TP and gender and the presence of torus mandibularis (TM) (P<0·001 OR=3·43, 95%CI=2·00-5·86; P<0·001, OR=2·63, 95%CI=1·64-4·24, respectively). This study suggests that genetic factors play a more significant role than factors related oromaxillofacial function in the aetiology of TP.

Why did the frequency of palatine torus increase in the ancient Anatolian populations?

The frequency of the palatine torus varies in various populations from different regions of the world. In this study, the change of frequency of palatine torus is examined using 387 skulls from 12 different ancient Anatolian populations in various periods ranging from the Early Bronze Age to the first quarter of the 20th century. While the frequency of palatine torus is 45% in the Early Bronze Age, this ratio steadily increases to 87% in the Ottoman Period and finally declines to 40% during the recent period. It was determined that the increase in the frequency of the palatine torus is statistically significant across different periods from the Early Bronze Age until the 20th century. Constituting a passageway between Asia and Europe and being located on the crossroads of the most important trade route of the Medieval Period, the Silk Road, Anatolia is known to have been subjected to recurring invasions and migrations since the 11th century A.D. Therefore, it is possible to say that, with the introduction of the Mongoloid influence in Anatolia, genetic flow has had a significant role in the observed increase in the frequency of this trait.

Prevalence and clinical characteristics of oral tori in 1,520 Chulalongkorn University Dental School patients

The objectives of this study were to determine the prevalence, size, shape and location of the oral tori in 1,520 Thai dental patients and to investigate the relationship between the findings with age and gender. The prevalence rates were 60.5% for torus palatinus (TP) and 32.2% for torus mandibularis (TM). The concurrence of TP and TM was noted in 23.2% subjects. The peak incidence of TP and TM was in the third decade of life. TP affected more women than men (70.5 vs. 48.8%, P < 0.001). Most TP were found in spindle shape (56%), small size (52.1%) and located at premolar region (47.4%). The occurrence of TM was higher in men than in women (36.3 vs. 28.6%, P = 0.002). TM was found most common in small size (65.6%), as bilateral multiple nodes (59.3%) and usually located at the premolars (89.2%). The age and gender-related differences with the size of tori were noted. Subjects who had larger TP or TM were older than those who had smaller TP or TM (P < 0.001 and P = 0.001, respectively). Women were more likely to have larger TP whereas men tended to have larger TM. This study showed high prevalence rates of TP and TM in dental patients and the occurrences were related to gender.

The frequency and anatomical features of torus mandibularis in a Black South African population

Torus mandibularis is a rounded bony protuberance on the lingual surface of the mandible and usually found above the myolohyoid line, medial to the molar roots. This report describes the frequency and morphology of torus and also proffers the likely cause among black South Africans. A total of 284 modern skeletal specimens were obtained from the Raymond Dart Collection of Human Skeletons at the School of Anatomical Sciences, University of the Witwatersrand. The mandibles were classified into dentate and edentulous, while those with torus, especially in dentate mandibles, were reviewed for side location, type and shape. No measurements were made, consistent with the view that these characteristics are non-metrical and should be assessed by means of a standard observatory procedure. Out of 246 dentate mandibles, 60 (24.4%) were found to have torus and only 1 (4.3%) out of the 23 male edentulous mandibles; the difference is statistically significant (P=2.8%). The torus distribution among males and females was 48 (80%) and 12 (20%), respectively, and again statistically significant (P< 0.05). Prevalence of torus was highest in the 40-60 years age group. The morphology of the torus showed that 37 (61.7%) were bilateral in location, 42 (70%) were of the solitary type and 31 (51.7%) were round in shape. The formation of torus follows the threshold model which holds that this is primarily a genetic trait, but with environmental factors such as mechanical stress necessary for its development.

Testicular cancer in a patient with Primrose syndrome

A mentally retarded, adult man was found to have joint contractures, sparse body hair, hearing loss, dysmorphic facial features, large calcified pinnae and a huge torus palatinus. All features are similar to those earlier described in patients with Primrose syndrome. In addition he developed a germ cell tumour of his right testicle at age 27 years. A comparison is provided between the main findings in the four previously reported cases with Primrose syndrome and the current patient. Calcification of the pinnae is an infrequent symptom in the general population, and a torus palatinus of limited size is commonly found but a torus of the size reported here is extremely unusual. Both symptoms are excellent handles for diagnosing this entity. It remains as yet uncertain whether an increased risk to malignancies forms part of this syndrome or is only a consequence of cryptorchidism in this patient.

Prevalence of torus palatinus in Turkish Schoolchildren

Torus palatinus (TP) is the most common exostosis of the maxillofacial skeleton. It usually does not cause symptoms, but removal may be required if it interferes with the function, denture placement, or suffers from recurring traumatic surface ulceration. Large variations in the prevalence of TP have been reported in different populations and were associated with age and sex. The aim of this study is to investigate the prevalence, size, and location of TP in a population of young Turkish. A total of 1,943 schoolchildren, 1,056 males and 887 females, ranging in age from 5 to 15 years were assessed for the prevalence, size and location of TP. Inspection and palpation were examined for the presence or absence of TP. The prevalence of the TP in study population was 30.9%. TP was found significantly more in females than in males (34.3, 28.1%, P<0.005). The more of TP were smaller than 2 cm (91.5%), and in molar location (62.9%). This study indicated that the prevalence of TP in Turkish population was high. There was a strong correlation between the prevalence of TP and age or sex.

Palatine torus in the pre-conquest inhabitants of the Canary Islands

An unusually high frequency of palatine torus in prehistoric Canary Islands skeletal remains is investigated in terms of population origins, evolutionary forces (gene flow and genetic drift) and environmental effects. Palatine torus frequencies (percent presence) are compared between the Canary Islands sample and skeletal samples from proposed ancestral regions, including northwest Africa, northeast Africa, sub-Saharan Africa, southern Europe, northern Europe and western Asia. The frequency of palatine torus is much higher in the Canary Islands sample (23.8%) than in samples from Northern and sub-Saharan Africa (1.8-6.1%), southern Europe (7.5%) and western Asia (2.1%), but is much lower than in the sample from northern Europe (57.4%). Because biological and archaeological evidence provide strong support for a northwest African origin for indigenous Canary Islands populations, the relatively high occurrence of palatine torus in the Canary Islands populace cannot be explained by an alternative ancestry; rather, it may be best explained by either evolutionary forces such as genetic drift or gene flow, or by environmental forces, such as hard chewing or a heavy dependence on marine foods. Genetic drift and gene flow seem less likely, since frequencies of other dental traits known to be under strong genetic control do not differ greatly between the prehistoric Canary Islands and northwest African samples. Environmental factors such as diet seem the most likely explanation and may include heavy consumption of marine foods, which has been implicated in torus formation.

Is torus palatinus a feature of a well-developed maxilla?

Torus palatinus (TP) is an exostosis of the hard palate. The biologic significance of TP is unknown. Our hypothesis was that the presence of a TP reflects the development of the maxilla. It has been proven that tooth agenesis is associated with small maxillary size. We investigated whether there is a relationship between maxillary third molar agenesis and the presence or absence of TP. The study was carried out on 253 Turkish patients. It showed a lower prevalence of third molar agenesis in female subjects with TP (P < 0.001). This study provides indirect evidence that development of the maxilla may be greater in female subjects with TP.

The role of occlusal stress and gingival infection in the formation of exostoses on mandible and maxilla from Neolithic China

Exostoses on the mandible and maxilla is a frequently observed bone growth of controversial aetiology. The aim of this study is to analyse environmental factors that may stimulate the formation of exostoses on different regions of the maxilla and mandible. Sixty-six well-preserved crania from Neolithic China were studied for the presence of buccal exostoses on the maxilla (BE) and lingual exostoses on the mandible (LME). Other oral health indicators, such as occlusal wear on molars, pathology of temporomandibular joint (TMJ), carious lesions, calculus accretion, periodontal disease, and antemortem tooth loss were recorded. Buccal maxillary exostosis was unusually common on the Neolithic skulls from China, which thus resemble the Sinantropus crania described by Weidenreich (1943). We report a significant Spearman correlation between BE and LME (rho = 0.54, P < 0.00001), suggesting a partially shared aetiology of these two types of exostoses. The highest correlations between either form of exostoses and any oral indicator of stress were found for pathology at TMJ (rho = 0.46, P < 0.0001 for both types of exostoses). Smaller but significant correlations were observed between LME and the age adjusted wear rate on lower molars, as well as between BE and indicators of oral/dental pathology, e.g. caries, calculus, periodontoses, and antemortem tooth loss. Both types of exostoses tended to increase in frequency with age, although a significant trend was observed only for BE. We conclude that formation of exostoses is a complex process that can be invoked by any agent causing damage and inflammation of gingival tissue. However, severe occlusal stress, which is often manifested in TMJ disorder, is the main environmental factor leading to exostosis development in genetically pre-disposed individuals.

Diet and health changes at the end of the Chinese neolithic: the Yangshao/Longshan transition in Shaanxi province

In this paper we discuss diet and health changes of millet agriculturists in Northern China, Shaanxi province, during the period 7,000-4,000 BP. An episode of intensive climatic oscillations that preceded the onset of colder climate circa the fifth millennium BP divides the period (Shi et al. [1993] Global Planet. Change 7:219-233). The onset of the cooler climate marks the decline of the egalitarian society of Yangshao and the rise of the chiefdom-like society of Longshan. Skeletal materials from the two sites of Beiliu and Jiangzhai are from the earlier phases of Yangshao culture (7,000-6,000 BP), while remains from the Shijia site were excavated from the terminal phase of Yangshao culture (6,000-5,000 BP), a phase that would be expected to show adjustments to strong climatic fluctuations. Human remains from the Longshan culture (5,000-4,000, BP) were found at the Kangjia site. In order to investigate whether the trajectory of diet and health changes persisted beyond the Longshan, a skeletal sample from the Xicun site of the Western Zhao Dynastic period (3,800-2,200 BP) is included in our analyses. All Yangshao sites in our study are characterized by low frequencies of anemia and carious lesions. Some subsistence changes probably occurred during the later phase of Yangshao culture that resulted in elevated masticatory stress and occlusal macrowear among the Shijia people. However, deterioration of community health did not begin until the Longshan, when increased occurrence of porotic hyperostosis and caries is accompanied by decreased adult stature. The transition to softer, more extensively processed food during Longshan is evident in decreased rates of occlusal wear. Increased population density and diminished food values were most likely responsible for these changes. Poor health persisted into the subsequent Dynastic period of Western Zhao.

An epidemiological study of tori among 667 dental outpatients in Trinidad & Tobago, West Indies

AIM

To study the prevalence of tori amongst dental outpatients, the ethnic and sex variations in their distribution, and their clinical features.

SETTING

The School of Dentistry, St. Augustine, Trinidad & Tobago.

PARTICIPANTS

667 consecutive dental outpatients representing three different ethnic groups of the country.

METHODS

Clinical examination for and recording of tori indicating their location, extent and clinical features and the age, sex and ethnic grouping of the patient.

RESULTS

The overall prevalence of tori was 12.3 per cent.

CONCLUSIONS

There were no significant differences in the prevalence among the African, Indian or mixed ethnic groups of patients examined. There seemed to be strong link between the coexistence of palatal and mandibular tori.

Buccal and palatal exostoses: prevalence and concurrence with tori

OBJECTIVES

The aims of this study were to investigate the prevalence and location of oral exostoses and the concurrence of buccal and palatal exostoses with tori.

STUDY DESIGN

With clinical inspection and palpation, 960 Thais were examined for the presence or absence of torus palatinus (TP), torus mandibularis (TM), and exostoses.

RESULTS

Of the 960 subjects studied, 26.9% exhibited exostoses. Exostoses were more common in the maxilla than in the mandible (5.1:1). In addition, most of the exostoses were located on the buccal aspect of the jaws. The prevalence of exostoses increased with age (P = .000). Exostoses were significantly more common in men than in women (62.4% vs 37.6%, P =.000). Exostoses were concurrent with TM more frequently than with TP (36.2% vs 20.6%). The highest concurrence of exostoses with tori was observed in subjects who had both TP and TM (42.6%).

CONCLUSIONS

The occurrence of exostoses is related to increasing age. TM and exostoses may share the same causative factors, and functional influences may contribute. Our findings lend support to the hypothesis that the etiology of exostoses involves an interplay of multifactorial genetic and environmental factors.