Shape and volume of craniofacial cavities in intentional skull deformations.

Intentional cranial deformations (ICD) have been observed worldwide but are especially prevalent in preColombian cultures. The purpose of this study was to assess the consequences of ICD on three cranial cavities (intracranial cavity, orbits, and maxillary sinuses) and on cranial vault thickness, in order to screen for morphological changes due to the external constraints exerted by the deformation device. We acquired CT-scans for 39 deformed and 19 control skulls. We studied the thickness of the skull vault using qualitative and quantitative methods. We computed the volumes of the orbits, of the maxillary sinuses, and of the intracranial cavity using haptic-aided semi-automatic segmentation. We finally defined 3D distances and angles within orbits and maxillary sinuses based on 27 anatomical landmarks and measured these features on the 58 skulls. Our results show specific bone thickness patterns in some types of ICD, with localized thinning in regions subjected to increased pressure and thickening in other regions. Our findings confirm that volumes of the cranial cavities are not affected by ICDs but that the shapes of the orbits and of the maxillary sinuses are modified in circumferential deformations. We conclude that ICDs can modify the shape of the cranial cavities and the thickness of their walls but conserve their volumes. These results provide new insights into the morphological effects associated with ICDs and call for similar investigations in subjects with deformational plagiocephalies and craniosynostoses.

A selective laser sintering guide for transferring a virtual plan to real time surgery in composite mandibular reconstruction with free fibula osseous flaps.

The free fibular flap is the standard procedure for reconstructing mandibular defects. The graft has to be contoured to fit the defect so preoperative planning is required. The systems used previously do not allow transfer of the surgical plan to the operation room in an optimal way. The authors present a method to bring the virtual plan to real time surgery using a rapid prototyping guide. Planning was conducted using the Surgicase CMF software simulating surgery on a workstation. The osteotomies were translated into a rapid prototyping guide, sterilised and applied during surgery on the fibula allowing for the osteotomies and osteosynthesis to be performed with intact circulation. During reconstruction the authors were able to choose the best site for the osteotomies regarding circulation and as a result increased the precision and speed of treatment.

Ways of understanding the encounter with head and neck cancer patients in the hospital dental team--a phenomenographic study.

INTRODUCTION: Head and neck cancer is the sixth most common malignancy in the world. Fifty percent of the patients can be cured by surgery, radiotherapy or a combination approach. Head and neck cancer is life-threatening, and treatment may leave the patient with visible facial disfigurements and impairment of functions such as speech and eating. This affects not only the patient, but may arouse difficult feelings in the treatment staff. Dental personnel are involved in all facets of treatment, yet they have no specific training in cancer care. BACKGROUND: The aim of this study was to describe the variation in ways dental personnel understand and experience the encounter with head and neck cancer patients, as the way of understanding a certain phenomenon is judged to be fundamental to the way we act and form our beliefs. METHODS: Twenty members of hospital dental teams were interviewed. The interviews focused on experiences of the encounter with head and neck cancer patients. A qualitative research approach, phenomenography, was used in analysing the interviews. The encounter was perceived in three qualitatively different ways: as an act of caring, as a serious and responsible task and as an overwhelming emotional situation. The results indicate that hospital dental personnel are not able to lean on education and professional training in finding ways of dealing with situations with strong emotional impact. This has implications for the treatment of patients with head and neck cancer, as well as education of dental personnel.

Oral cancer after using Swedish snus (smokeless tobacco) for 70 years - a case report.

Whereas the smoking habit has declined significantly in Sweden in recent decades, there has been a marked increase in the consumption of 'snus' (oral moist snuff). The use of this smokeless tobacco, exposing the user locally to carcinogenic nitrosamines, raises the question - will the increasing use of snuff eventually lead to a greater incidence of oral cancer? We report the case of a 90-year-old man who developed a localized squamous cell carcinoma in the gingival fold under the upper lip, at the exact place where he had regularly placed loose oral snuff for 70 years. Although this is a reminder of a prevailing cancer risk, the time frame indicates that the risk is slight. This is consistent with recent epidemiological reports regarding the minor risk of snuff-associated cancer in the Scandinavian countries.

Effects of long-term administration of cancer-promoting substances on oral subepithelial mast cells in the rat.

The role of oral subepithelial mast cells in the defence against tumours is a matter of controversy. The effect of established and suggested carcinogens, such as the carcinogen 4-nitroquinoline-N-oxide (4-NQO) and Herpes simplex virus type 1 (HSV-1), in combination with oral snuff on lower lip subepithelial mast cells (MC) was studied in rats. The rats were exposed to prolonged use of oral snuff. The test substances were administered in a surgically created canal in the lower lip of the rats. There were 15 rats in each test group and 10 rats in the control group. The amount of countable subepithelial mast cells decreased significantly when the rat oral mucosa was exposed to the oral carcinogen 4-NQO but the effect of oral snuff and HSV-1 infection was weak. Our findings suggest that mast cells play a role in immunological cell defence against chemical carcinogens. Further studies are needed to clarify the mechanisms.

Sinus lifting procedure. I. One-stage surgery with bone transplant and implants.

A prospective study of one-stage surgery with intrasinus bone transplant and implants has been performed in 26 patients (13 males and 13 females). The aim of the study was to evaluate the success rate with the one-stage sinus lifting procedure in patients with a need for bony augmentation of the alveolar process. Fifteen patients were partially dentate and 11 edentulous. The mean height of the alveolar ridge was 2.5 mm preoperatively (range 1-5.5 mm). 126 fixtures were inserted, 93 in grafted bone and 33 in alveolar bone. Twenty-two patients have been followed for three years, 21 for four years and 11 for five years. The clinical overall survival rate was 69.6% although only 61.2% in grafted bone. Ten of the patients had varying degree of sinusitis post-fixture installation. At the end of the study, 23 patients had permanent bridges. The survival rate was low for inlay supported implants when the one-stage surgical technique was applied. Two-stage surgery may be a safer method.

Volumetry of simulated bone grafts in the edentulous maxilla by computed tomography: an experimental study.

OBJECTIVE: To determine the precision of CT for calculating the volume of bone grafts to the maxilla. METHODS: Plaster of Paris was used to simulate bone as onlay and inlay grafts to the maxillary alveolus and sinus in a dry skull. Two mm thick axial CT scans were obtained. The area of the graft on each slice was measured and volumes calculated according to the formula V(graft)=Sigma of areas x the thickness of each section. Scans were repeated with the skull at approximately +5 degrees and -5 degrees to the horizontal plane and the calculations repeated. The real volume was calculated by the displaced water technique. Precision was estimated as reliability coefficient. RESULTS: The reliability coefficients for the right and left inlay and the onlay grafts were 0.97, 0.6 and 0.96 respectively. CONCLUSION: Calculations of the volume of both inlay and onlay grafts to the maxilla from axial CT is precise.

A clinical study of changes in the volume of bone grafts in the atrophic maxilla.

OBJECTIVES: To evaluate the volumetric changes in bone grafts to the severely atrophic edentulous maxilla over 6 months. METHODS: Ten edentulous patients received autogenous bone as buccal onlay grafts to the maxilla and bilaterally particulate bone grafts to the maxillary sinus. Two mm contiguous axial CT scans were obtained 1 to 2 weeks and 6 to 7 months postoperatively. The area of each graft was measured and the volume calculated according to the formula V(graft)=Sigma of areas x the thickness of each section. RESULTS: The volume of the inlay and onlay grafts was reduced by an average of 49.5 and 47% respectively of the initial volume. The coefficient of variation was greater in the onlay group (0.79) compared with the inlay group (0.38). CONCLUSIONS: The volumetric changes in buccal onlay and sinus inlay grafts after 6 months of healing seem similar although there was a wide range in both groups.

A randomized, double-blind, placebo-controlled clinical evaluation of a nicotine sublingual tablet in smoking cessation.

AIMS: Evaluation of the clinical efficacy and safety of a nicotine 2-mg sublingual tablet in smoking cessation. DESIGN: A randomized, double-blind, placebo-controlled study of smokers using the 2-mg tablet for 3-6 months with follow-up to 12 months. Dosing was established according to baseline nicotine dependence, scored on the Fagerström Tolerance Questionnaire (FTQ): FTQ > or = 7, two tablets/hour (maximum 40/day); FTQ < 7, one tablet/hour (maximum 20/day). SETTING: Smoking cessation programme in a department of oral and maxillofacial surgery. PARTICIPANTS: A total of 247 adult smokers, smoking > or = 10 cigarettes/day for > or = 3 years, of whom 123 received active and 124 placebo treatment. The study was powered to detect difference at 6 months. MEASUREMENTS: Efficacy and safety were evaluated at 6 weeks and 3, 6 and 12 months. Self-reported abstinence was verified by exhaled CO < 10 p.p.m. FINDINGS: Success rates for complete abstinence (no slips after 2 weeks) for active vs. placebo were 50% vs. 29% at 6 weeks, 42% vs. 23% at 3 months, 33% vs. 18% at 6 months and 23% vs. 15% at 12 months (p < 0.001, 0.001, 0.005 and p = 0.14), respectively. Craving during the first 8 days was significantly reduced among highly dependent smokers on active treatment compared to placebo. Baseline mucosal lesions among abstinent subjects were reduced during the treatment period and at the non-treatment follow-up. Adverse events were mild and tolerable, the most common being irritation and soreness in the mouth and throat. CONCLUSION: The nicotine sublingual tablet increased the smoking cessation rate compared to placebo, reduced craving in highly dependent smokers and was well tolerated.

Presence of human papilloma viruses in intraosseous ameloblastoma.

PURPOSE: This study investigated the possibility that human papilloma virus (HPV) is a possible etiologic agent in the development of ameloblastoma. MATERIALS AND METHODS: DNA was extracted from 18 formalin-fixed, paraffin-embedded biopsy specimens and assayed for the presence of HPV DNA by PCR using the L1 consensus primer and specific primers for HPV types 6/11, 16 and 18. RESULTS: Eight samples (67%) were positive for HPV. Of the 8 HPV-positive samples, 7 were positive for HPV 18. Four of the HPV 18-positive samples were also positive for HPV 6/11. One HPV-positive sample was not positive for any of the type-specific primers. CONCLUSIONS: No conclusions can be drawn about the etiologic role of HPV from this study, but surgical manipulation is suggested to be one of the reasons for HPV presence attributable to contamination from the surface mucosal epithelium in these tumors.

Human papilloma viruses in oral lesions.

Oral mucosa biopsies from 53 patients with different oral diseases, and from 12 healthy control patients, were examined by the PCR-technique using the L1 consensus primers and type-specific primers for HPV 6/11, 16 and 18. Three out of 24 (12.5%) oral cancer biopsies were HPV positive, 1 for HPV 18, 1 for HPV 16 and 6/11 and 1 for none of the specific primers. Six out of 22 (27.3%) lichen planus were HPV positive, 5 for HPV 18 and 1 for none of the specific primers. Seven leukoplakias were included in the study and 2 (29.6%) were positive for both HPV 16 and 6/11. None of the 12 control patients was HPV positive. No statistical difference between the use of tobacco and alcohol and HPV prevalence was found. An association between HPV infection and oral lesions was demonstrated in the studied population but the pathogenic influence of HPV infection remains unclear.

Epstein-Barr virus and human papillomavirus in snuff-induced lesions of the oral mucosa.

Epstein-Barr virus (EBV) and human papillomavirus (HPV) have been associated with benign as well as malignant oral lesions. We examined 43 patients with snuff-induced lesions and 22 control patients with clinically healthy oral mucosa for the presence of HPV and EBV. Polymerase chain reaction was performed on fresh frozen oral biopsies with degenerate consensus primers for HPV and nested primers for EBV. None of the 43 snuff-induced lesions or the 22 control biopsies were HPV-positive. Seven of the 43 (16.3%) snuff-induced lesions and one of the 22 (4.5%) controls were positive for EBV. The snuff-induced lesions were classified according to clinical severity, grade 1 lesions being the least severe and grade 4 the most severe. Eleven percent of grade 2 lesions, 15.8% of grade 3 lesions and 20% of grade 4 lesions were EBV-positive. Neither EBV nor HPV seem to be associated with snuff-induced lesions.

Hydroxyapatite granule/carrier composites promote new bone formation in cortical defects.

BACKGROUND: A great deal of interest has been focused on finding substitutes for autogenous bone grafts. Among the most interesting materials are different calcium phosphate compositions (e.g., hydroxyapatite [HA]), due to their biocompatible properties in hard and soft tissue. PURPOSE: The bone response to porous ceramic HA granules in combination with two lipid and one polysaccharide carrier was evaluated in an experimental bone defect model in rabbits. MATERIALS AND METHODS: Circular defects (Ø 4 mm) were made in both tibias of 32 rabbits. The 64 defects were divided into four groups. Group A was augmented with a composite of HA granules and a phospholipid-diacetyl-glycerol carrier, group B with HA granules and a phospholipid carrier, group C received HA granules and a sodium hyaluronan carrier, and group D served as control. The animals were killed after 6 weeks and ground sections were evaluated using light microscopic morphometry. X-ray microfluorescence (XRF) was applied in order to evaluate the suitability of this method to examine bone-biomaterial interfaces. Calcium distribution was studied using x-ray fluorescence line scans at selected interface regions of two sections in group B. RESULTS: The HA/phospholipid composites were easier to shape and handle than the HA/hyaluronan composite. Group A had 36% newly formed bone area within the defect. Groups B and C showed significantly more newly formed bone within the defect (47% and 49%, respectively) compared to the control group (31%). The XRF analysis revealed that the amount of calcium in the newly formed bone was similar to that observed for the HA granules and slightly lower when compared to the mature, lamellar bone. CONCLUSIONS: Synchrotron radiation may be a new, suitable technique to study the interface between bone and biomaterials with regard to mineral content. The results suggest that HA granule/lipid and HA granule/hyaluronan composites have interesting properties as bone-substitute materials.

The long-term effect of nicotine on the oral mucosa.

AIMS: Although nicotine replacement therapy (NRT) has been used to aid smoking cessation for the last 20 years, little information exists on the effect of nicotine products on the oral mucosa, particularly with regard to the direct effect at the site of application. This study aimed to assess the oral safety of a new sublingual tablet containing 2 mg nicotine with regard to lesions at the site of application. DESIGN: Prospective follow-up to 12 months of smokers using the 2-mg sublingual tablet over a period of 3-6 months. SETTING: A smoking cessation programme. PARTICIPANTS: Thirty smokers. MEASUREMENTS: Oral mucosa was inspected and photographed at each visit. At 6 months, subjects were asked for consent to take a biopsy from the site of application. FINDINGS: Spontaneous smoking cessation outcome at 12 months was 27% allowing for lapses. At baseline 21 mucosal lesions were diagnosed in 15 subjects. After 6 months eight lesions were observed in six subjects. The predominant diagnosis at all visits was melanin pigmentation. Eight subjects had lesions in the floor of the mouth during the 6-month medication period, all of which appeared in the first 1-6 weeks of treatment. By the 6-month visit all such lesions had resolved. The local symptoms were all mild and tolerable. CONCLUSION: The sublingual tablet appears to be a safe form of administration of nicotine with mild and transient effects on the floor of the mouth.

High-throughput DNA extraction from old paraffin-embedded biopsies.

We have developed a rapid and reliable microporous spin-column-based method for high-throughput extraction of DNA from old paraffin-embedded biopsies. The method was developed specifically for PCRs and molecular genetic studies. De-waxing and DNA extraction from tissues is performed in only one vessel, minimizing pipetting steps and eliminating supernatant/pellet procedures. All steps are performed at 60 degrees, 55 degrees and 95 degrees C minimize deleterious DNase activity. The amount of the extracted DNA was measured spectrophotometrically, and the quality of the extracted DNA and the PCR products was controlled on ethidium bromide-stained 3% agarose gel. The presented method for DNA extraction is less laborious and more convenient than previously published methods. It provides means by which extensive, paraffin-embedded material can be subjected to molecular genetic studies.

Surface analysis of failed oral titanium implants.

The aim of the present study was to investigate the surface topography, composition, and oxide thickness of consecutively failed, oral Brånemark implants in order to determine possible causes for failure. The failure criterion was lack of osseointegration manifested as implant mobility. Ten implants were retrieved before loading (early failures) and 12 during a period of function up to 8 years (late failures). At retrieval, early losses did not display any clinical sign of infection. All late failures were radiographically characterized by peri-implant radiolucency and did not show infectious signs with one exception. No implant seemed to be lost due to peri-implantitis (plaque-induced progressive marginal bone loss). Twelve implants were analyzed by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), and depth profiling using a blind protocol. Two pristine fixtures, which underwent the same preparation as the failed implants, were used as controls. In the SEM, control samples were essentially free from macroscopic contamination, whereas failed implants contained varying amounts of tissue residues. AES showed that all surfaces consisted of Ti oxide and varying amounts of additional elements, with C dominating in most cases. Nitrogen and sometimes Na, Ca, P, Cl, S, and Si were detected. The Si contamination was most likely due to ion leaching from the glass vials used for storage. Depth profiles showed a typical oxide thickness of 5-8 nm for all samples. In conclusion, no significant changes in the oxide layer composition or thickness as a result of implantation were observed. The results do not indicate any material-related cause for the failures of these implants. Possible reasons for these failures were impaired healing, asymptomatic infection, and overload.

Biological factors contributing to failures of osseointegrated oral implants. (II). Etiopathogenesis.

The aim of the present review is to evaluate the English language literature regarding factors associated with the loss of oral implants. An evidence-based format in conjunction, when possible, with a meta-analytic approach is used. The review identifies the following factors to be associated with biological failures of oral implants: medical status of the patient, smoking, bone quality, bone grafting, irradiation therapy, parafunctions, operator experience, degree of surgical trauma, bacterial contamination, lack of preoperative antibiotics, immediate loading, nonsubmerged procedure, number of implants supporting a prosthesis, implant surface characteristics and design. Excessive surgical trauma together with an impaired healing ability, premature loading and infection are likely to be the most common causes of early implant losses. Whereas progressive chronic marginal infection (peri-implantitis) and overload in conjunction with the host characteristics are the major etiological agents causing late failures. Furthermore, it appears that implant surface properties (roughness and type of coating) may influence the failure pattern. Various surface properties may therefore be indicated for different anatomical and host conditions. Finally, the histopathology of implant losses is described and discussed in relation to the clinical findings.

Expression of keratin 13, 14 and 19 in oral hyperplastic and dysplastic lesions from Sudanese and Swedish snuff-dippers: association with human papillomavirus infection.

Changes in the expression of keratins (Ks), indicating disturbed tissue differentiation, is one possible marker of malignant potential in stratified squamous epithelia. The presence of human papillomaviruses (HPVs) in the epithelium of the uterine cervix is increasingly regarded as a marker of risk for cervical cancer: However, a similar role in oral cancer and precancer remains controversial. To address these questions, potentially malignant oral mucosal lesions from Sudanese (9 hyperplasias/40 dysplasias) and Swedish (15 hyperplasias) snuff-dippers were examined by immunohistochemistry for expression of K types 13, 14 and 19 using monoclonal antibodies directed against each. HPV infection was searched for by in situ hybridization (ISH) using the cocktail HPV OmniProbe and the ViraType probe. For the Sudanese lesions, moderate to intense expression of both K13 (basal, basal/intermediate, basal/intermediate/superficial and intermediate/superficial cell layers) and K14 (basal, basal/intermediate cell layers) was found in 49/49 (100%). For the Swedish lesions, weak to moderate expression of K13 (basal, basal/intermediate cell layers) was found in 12/15 (80%) and 10/15 (67%), respectively. In the Sudanese lesions, expression of K13 showed a distinct pattern through the oral mucosa and its verrucous projections, with an increase towards the superficial cell layers of dysplastic, but not hyperplastic epithelium. K19 was expressed in the basal cell layer in 16/49 (33%) of the Sudanese lesions, while all the Swedish lesions were negative. HPV was found in only 2 Sudanese cases, both of which harboured both type 6 and type 11: both these cases demonstrated mild epithelial dysplasia, The present study shows that a) there is a high prevalence of expression of both K13 and K14 in oral lesions from Sudanese toombak dippers indicating dysregulation of keratinocyte maturation b) one-third of the Sudanese oral lesions expressed K19, regarded as a basal keratin representing epithelial dedifferentiation, which may prove to be a valuable risk marker in follow-up studies c) HPV genome is found infrequently in oral lesions from Sudanese toombak-dippers, suggesting that these viruses may not play a prominent role in the early stages of carcinogenesis in these subjects. These markers were less often expressed in the Swedish lesions, consistent with their much lower rate of malignant transformation.

Biological factors contributing to failures of osseointegrated oral implants. (I). Success criteria and epidemiology.

The aim of this review was to offer a critical evaluation of the literature and to provide the clinician with scientifically-based diagnostic criteria for monitoring the implant condition. The review presents the current opinions on definitions of osseointegration and implant failure. Further, distinctions between failed and failing implants are discussed together with the presently used parameters to assess the implant status. Radiographic examinations together with implant mobility tests seem to be the most reliable parameters in the assessment of the prognosis for osseointegrated implants. On the basis of 73 published articles, the rates of early and late failures of Brånemark implants, used in various anatomical locations and clinical situations, were analyzed using a metanalytic approach. Biologically related implant failures calculated on a sample of 2,812 implants were relatively rare: 7.7% over a 5-year period (bone graft excluded). The predictability of implant treatment was remarkable, particularly for partially edentulous patients, who showed failure rates about half those of totally edentulous subjects. Our analysis also confirmed (for both early and late failures) the general trend of maxillas, having almost 3 times more implant losses than mandibles, with the exception of the partially edentulous situation which displayed similar failure rates both in upper and lower jaws. Surgical trauma together with anatomical conditions are believed to be the most important etiological factors for early implant losses (3.60% of 16,935 implants). The low prevalence of failures attributable to peri-implantitis found in the literature together with the fact that, in general, partially edentulous patients have less resorbed jaws, speak in favour of jaw volume, bone quality, and overload as the three major determinants for late implant failures in the Brånemark system. Conversely, the ITI system seemed to be characterized by a higher prevalence of losses due to peri-implantitis. These differences may be attributed to the different implant designs and surface characteristics. On the basis of the published literature, there appears to be a number of scientific issues which are yet not fully understood. Therefore, it is concluded that further clinical follow-up and retrieval studies are required in order to achieve a better understanding of the mechanisms for failure of osseointegrated implants.

The Swedish snus and the Sudanese toombak: are they different?

In Sweden, snuff (locally known as snus), was introduced since the year 1637. Presently, Sweden has the highest per capita consumption and sale figures of snuff in the world, and the habit is becoming increasingly popular. Snus is manufactured into a dry form used in the nasal cavity and a moist form used in the oral cavity. Snus manufactured for oral use is a moist ground tobacco of Dark Kentucky or Virginia species mixed with an aqueous solution of water and other blending ingredients. This form of snuff is found in two types: (1) loose and (2) portion-bag-packed. These are the most widely used. The loose moist form (1-2 g a quid) is the most popular type consumed by 73% of the males, followed by the portion-bag-packed form (0.5-1 g a quid), consumed by 13% of the males, while 14% of the males are mixed users. The majority of snus users place the quid in the vestibular area of the upper lip, and the prevalence among persons 15 years of age or older in 15.9% among males and 0.2% among females. The pH of snus has declined from a previous range of 8-9 to a range of 7.8-8.5, moisture content ranges 35-60% and nicotine content is in the order of 5-11 mg/g dry wt tobacco-specific N-nitrosamines (TSNAs) in micrograms (N'-nitrosonornicotine: NNN 5-9; 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone: NNK 1-2; N'-nitrosoanatabine: NAT 2-5). In the Sudan, snuff, locally known as toombak, was introduced approximately 400 years ago. It is always processed into a loose moist form, and its use is widespread in the country. Tobacco used for manufacture of toombak is of the species Nicotiana rustica, and the fermented ground powder is mixed with an aqueous solution of sodium bicarbonate. The resultant product is moist, with a strong aroma, highly addictive and its use is widespread particularly among males. Its pH range is 8-11, moisture content ranges 6-60% and nicotine content is from 8 to 102 mg/g dry wt, and TSNAs contents in micrograms (NNN 420-1 550; NNK 620-7 870; NAT 20-290). Snus and toombak dippers develop a clinically and histologically characteristic lesion at the site of dipping. Probably due to control of the TSNAs in snus, this type of snuff is associated with a lower risk of cancer of the oral cavity (relative risk: RR 5-6-fold), whereas the risk for cancer of the oral cavity among toombak users was high (RR 7.3-73.0-fold). In conclusion, the two snuff products significantly differ in many aspects. Most notable differences are tobacco species, fermentation and ageing, nicotine and TSNAs content, pH, expression of the p53 tumour suppressor gene, and keratin types 13, 14, and 19. It was, therefore, the object of the present study to highlight the oral health hazards of toombak, and to compare it with snus regarding the aforementioned differences.