Practice valuation: an analytical approach

Purchasing a dental practice is difficult. To help make this decision process more manageable, practitioners, practice management consultants, and practice appraisers often use standard valuation methodologies. Although useful, many of these models are simplistic, arbitrary, and dependent on criteria that are often susceptible to substantial subjectivity. Therefore, practice valuation results are often disputed. The capitalization of income method removes much of the subjectivity often associated with practice valuation and provides a more reliable assessment of the value of a practice.     

Bifurcation of external jugular vein: an anatomical variation during neck dissection

Background

The pattern of venous drainage of head and neck involves single external jugular vein bilaterally.

Methods and results

We report a case of bifurcation of the external jugular vein observed during a neck dissection procedure.

Conclusions

Anatomical variations in drainage pattern of superficial veins of the head and neck are important for head and neck surgeries including for anastomosis during free tissue transfer for head and neck reconstruction.

     

Anatomic position of the lingual nerve in the mandibular third molar region with special consideration of an atrophied mandibular crest: an anatomical study

The position of the lingual nerve in the mandibular third molar region was measured and documented in 68 cadaver dissections (34 adult cadaver heads). In 8.8% of the dissections, the lingual nerve was found at or above the level of the alveolar crest. In the horizontal plane, the nerve contacted the lingual plate of the third molar in 57.4% of the specimens. There was also a significant relationship between the degree of mandibular crest atrophy and the distance from the nerve to the molar region. The distance decreased with the degree of atrophy. There was no significant difference between the two sides of the head. These results demonstrate the vulnerability of the lingual nerve as it medially passes the mandibular third molar and may help avoid lingual damage during surgery in the third molar and retromolar region of the mandible.     

Granulocytic sarcoma of the lips: report of an unusual case

Granulocytic sarcoma (GS) is a rare localized, extramedullary tumor composed of immature cells of granulocyte series. It is capable of marked local tissue destruction. This condition can be a precursor of acute myeloid leukaemia by months or years making its diagnosis critical. Its occurrence has been described in multiple sites including skin, lymph nodes, bone, and visceral organs. It is extremely rare in the oral cavity and only 30 cases have been reported in the literature to date and often as a lump in the gingiva, palate, and extraction sockets. We describe the first reported case of GS presenting as a solitary lump in the lip and review the pertinent literature.     

Important arterial supply of the mandible,control of an arterial hemorrhage,and report of a hemorrhagic incident

Penetration of the mandibular cortex during dental implant surgery may damage 3 important arteries and could lead to life-threatening circumstances. To lessen the likelihood of lateral angulations and cortical perforations, dental implants of less than 14 mm may be considered for the mandible. The courses of the inferior alveolar, facial, and lingual arteries and their branches are reviewed. Management of hemorrhage from a branch of the lingual or facial arteries may require an extraoral approach for ligation, because the mylohyoid, sublingual, and submental arteries can anastomose and be anatomically variable as well. A violation of 1 of these may be difficult to manage and lead to a compromise of the airway. A cortical perforation may be avoided by studying the anatomy of the ridge being treated. This article discusses what procedures to perform to obtund bleeding from 1 of these arteries and the technique of performing an emergency tracheotomy.     

Oral health changes in an adult Norwegian population: a cohort analytical approach

Abstract – Objectives: The purpose of this analysis was to study temporal variation in oral health in an adult population. The cohort analysis comprised 1) estimation of longitudinal, cross‐sectional, and time‐lag differences in caries and treatment experience of the adult population in Trøndelag from 1973 to 1983 and to 1994; 2) assessment of which of the effects of age, period and cohort was the most plausible explanation for the observed differences and 3) discussion of causal and other factors underlying the effects of age, period and cohort. Methods: Cohort analysis was used to study changes in oral health over time. Study participants were selected by random sampling in 1973, 1983, and 1994 (n=1959, n=3195, n=2341 respectively). The methods of data collection comprised standardised clinical measurements and a self‐administered questionnaire. Cohort tables were established to analyse changes in DFT from 1973 to 1983 and DFT and DFS from 1983 to 1994. Results: Four patterns of changes in oral health were identified from adolescence to older adulthood. They point in different directions which indicate that complex processes are present. There were two and three significant changes in the subsets of analysis. Assumptions and conditions that allow identification of separate cohort, period, and age effects appeared not to be present. The pattern of changes was consistent with main effects of both age, period, and cohort. The effects were discussed from the perspective of the chosen frame of explanatory factors. Conclusions: The changes in oral health between populations in 1973, 1983 and 1994 were the combined consequences of simultaneously occurring factors that account for both age, period and cohort effects.     

Dental health patterns in young adults in Lithuania: an exploratory,analytical approach

Patterns of variation in experience related to caries and treatment with regard to psychosocial, socioeconomic, lifestyle, and oral healthcare-related characteristics were explored. A random sample of 382 (response rate 51%) subjects residing in 10 areas of Lithuania was examined (35 to 44-year-olds). Participants were given a dental examination and asked to complete a structured questionnaire. Experience related to caries and treatment differed with regard to residency and between genders. Analysis of self-reported data elucidated different aspects of psychosocial and socio-economic status and a variety of lifestyle factors. Interrelationships between the studied determinants were also analysed. Different patterns of dental health were revealed for men and women and for urban and rural participants. It can be concluded that factors influencing the dental status of Lithuanians are not only multiple, they seem also to influence dental health in complex ways. An exploratory approach should therefore be considered as a prerequisite to a causal approach of studying caries in populations.     

Dental health patterns in young adults in Lithuania: an exploratory,analytical approach

Patterns of variation in experience related to caries and treatment with regard to psychosocial, socio-economic, lifestyle, and oral healthcare-related characteristics were explored. A random sample of 382 (response rate 51%) subjects residing in 10 areas of Lithuania was examined (35 to 44-year-olds). Participants were given a dental examination and asked to complete a structured questionnaire. Experience related to caries and treatment differed with regard to residency and between genders. Analysis of self-reported data elucidated different aspects of psychosocial and socio-economic status and a variety of lifestyle factors. Interrelationships between the studied determinants were also analysed. Different patterns of dental health were revealed for men and women and for urban and rural participants. It can be concluded that factors influencing the dental status of Lithuanians are not only multiple, they seem also to influence dental health in complex ways. An exploratory approach should therefore be considered as a prerequisite to a causal approach of studying caries in populations.     

腭部血液供应的应用解剖学研究

目的 探讨腭部血管的来源、走行、分布,观察微血管系统的构筑形态。方法 发育正常头部标本14例,腭裂标本10例,血管灌注后通过显微解剖、X线摄片、显微镜及扫描电镜观察分析。结果 硬腭的血供主要来源于腭大动脉。小动脉分支呈“树枝状”,微动脉平行排列,毛细血管结构松散。腭升动脉是软腭的主要供血动脉。软腭的血管网可分为3层。小动脉分支角度多变,毛细血管网结构紧密。腭裂者血管来源与健康人相同,但走行、分布上有自身特点。结论 软硬腭的血液供应分别来源于不同的动脉,血管网的构筑形态也各具特点。     

The arterial blood supply of the human mandible]

The arteries of 22 mandibles injected with Kallocryl M were examined. The first group consisted of mandibles with the full complement of teeth. At the inner side, there were numerous anastomoses between the submental artery, the sublingual artery, the ascending palatine artery and the mylohyoid ramus. Furthermore, the dental rami branched into the periost. At the outside, the mental artery as well as the submental and inferior labial arteries contributed to the arterial supply. In the second group of mandibles (with intact incisors), these war a marked reduction of the anastomoses of the inferior alveolar artery in the middle region. The third group of mandibles (which were edentulous) showed anastomoses of the submental and sublingual arteries in the region of the incisors. The outside was supplied by the submental and inferior labial arteries. The mental artery exislar artery was demonstrated in 4 cases. The reduction of anastomoses concerned the inferior alveolar artery.     

Positional changes of the lips concomitant to incisor retraction: an important issue in orthodontics

Lip response to incisor retraction following extraction therapy is continuously investigated. The following is a summary of available evidence in this regard. The reaction of the lips to incisor retraction cannot be predicted with certainty. This is due to many variables such as gender, growth, morphology, and function. Also, for some patients, it is difficult to completely relax their lips during cephalogram taking. All these variables interact in studies on this topic.     

Bifurcation of the inferior dental nerve canal: an anatomical study

The aims of this study were to find the incidence of bifurcation of the inferior dental nerve (IDN) canal, to describe the characteristics of this variant, and to examine the sensitivity and specificity of dental panoramic tomography to identify it. We classified bifurcations by size and position relative to the main canal and the lower third molar using cone-beam computed tomography (CT) and dental panoramic tomography. In our study of 281 patients, 106 (38%) had bifurcations, and in one quarter, these were classified as large accessory canals. Bifurcations were most commonly found posterior to the lower third molar (n = 64, 57%) or within 2 mm of the roots of the third molar (n = 40, 38%). The sensitivity and specificity of dental panoramic tomography to identify all bifurcations was 11% (95% CI: 5.67 to 17.97) and 91% (95% CI: 85.58 to 94.68), respectively; this was 33% (95% CI: 15.63 to 55.32) and 94% (95% CI: 90.34 to 96.50), respectively, for large bifurcations. Our use of cone-beam CT suggested an incidence of bifid canals of 38%, with a variation in size and distribution in relation to the lower third molar. It also showed that the sensitivity of panoramic radiography to identify them was poor.     

Craniofacial asymmetry in development: an anatomical study

The purpose of this study was to evaluate the occurrence of craniofacial asymmetries in four areas of human skulls of various age groups to test the hypothesis that there is craniofacial symmetry before the chewing habit is established. The data were obtained from 95 skulls of fetuses, infants, children, and adults, from the collection of Federal University of S?o Paulo. The following measurements were taken on each skull with a digital caliper: from the infraorbital foramen to the anterior nasal spine (IOF); from the greater palatine foramen to the posterior nasal spine (GPF); from the spinous foramen to the basion (SF); and from the spinous foramen to the zygomatic arch (ZA). On different occasions, each measurement was taken three times on both sides of the skull in random order. The mean of the right-side measurements were subtracted from the mean of the left-side measurements, and the differences were transformed into percentages. Comparisons were made by analysis of variance. The presence of cranial asymmetry was statistically significant throughout the whole sample. The minimum value found was 2.8% and the maximum 6.5%. All age groups presented the same degree of asymmetry of distances IOF, GPF, and SF. The group of infants presented a higher degree of asymmetry on distance ZA, followed by the groups of fetuses, children, and adults. This study confirmed statistically significant craniofacial asymmetry in fetuses and infants (before dentition). Therefore, the hypothesis that craniofacial asymmetry only appears after establishment of the chewing habit was not supported.