A 10-year comparative study of the incidence of third molar removal in the aging population.

PURPOSE: The study goal was to evaluate the incidence of patients older than 40 years who required third molar removal. PATIENTS AND METHODS: Two prospective 5-year studies were compared over a 10-year period of 1992 to 1997 and 1997 to 2002. The study was initiated to evaluate how the large increase in the older population with longer life expectancies is reflected in the third molar population. RESULTS: In 1997, 10.5% of patients requiring third molar surgery were 40 years or older. In 2002, 17.3% of patients were 40 years or older. CONCLUSIONS: It is well known that patients 40 years and older have increased risk in removal of third molars. It is concluded that 1 patient in 5 in the high-risk category is in a very high risk category. The risk to patients and to the profession can be dramatically reduced by considering early removal of abnormal third molars.     

Influence of phase transformation on the torsional and bending properties of nickel-titanium rotary endodontic instruments

AIM: To investigate the relationship between the functional properties and the phase transformation of nickel-titanium endodontic instruments. METHODOLOGY: Five types of rotary nickel-titanium endodontic instruments with a 0.30 mm diameter tip (EndoWave, HERO 642, K3, ProFile.06, and ProTaper) were selected to investigate torsional and bending properties, and phase transformation behaviour. A torsional test was performed according to ISO publication 3630-1, and maximum torque and angular deflection at fracture were measured. Bending load of the instruments was measured in a cantilever-bending test at 37 degrees C with the maximum deflection of 4.0 mm. A stainless steel K-file was used for reference. Phase transformation behaviour was measured by differential scanning calorimetry (DSC). From the DSC curve, transformation temperatures were calculated. Data were analysed by anova and the Tukey-Kramer's test. RESULTS: The maximum torsional torque values of HERO, K3 and ProTaper were significantly higher (P < 0.05) than those of EndoWave, ProFile and K-file. The K-files had the lowest torque value. Angular deflection at fracture was significantly higher (P < 0.05) for K-files than that for any nickel-titanium instrument. The bending load values of HERO and K3 were significantly higher (P < 0.05) than those of EndoWave, ProFile, ProTaper and K-file. The K-files had the lowest load value, although residual deflection remained. The transformation temperatures of HERO and K3 were significantly lower (P < 0.05) than those of EndoWave, ProFile and ProTaper. CONCLUSIONS: The functional properties of nickel-titanium endodontic instruments, especially their flexible bending load level, were closely related to the transformation behaviour of the alloys.     

Palatal neurofibroma associated with localized periodontitis

BACKGROUND: Neurofibromatosis type 1 (NF1) is the most common form of neurofibromatosis. While typically considered a dermatologic disorder, intraoral signs of neurofibromatosis occur quite commonly. This clinical entity can be confused with periodontitis because of the presence of periodontal pockets. In this report, we present the case of a palatal neurofibroma with radiographic involvement in a patient with NF1. METHODS: A 40-year-old female patient was referred from her general dentist to evaluate advanced periodontitis in the maxillary left quadrant. The patient's medical history was significant for a soft tissue lesion excised from her back 11 years previously and diagnosed as a neurofibroma. Subsequent medical examination at that time confirmed a systemic diagnosis of NF1. A comprehensive periodontal evaluation was performed, and panoramic and periapical radiographs were taken. Teeth were tested for vitality. An incisional biopsy was completed for histopathologic examination. RESULTS: The periodontal evaluation revealed the presence of 6 to 9 mm probing depths adjacent to teeth #14 and #15. Panoramic and periapical radiographs showed a circumscribed 0.8x0.9-cm unilocular radiolucency superimposed over the root of tooth #13 and extensive horizontal bone loss on the distal side of #15. Incisional biopsy confirmed the presence of a neurofibroma, and because of the extent of the lesion, the patient was referred to the Oral and Maxillofacial Surgery service for complete excision. CONCLUSIONS: Neurofibromas can cause extensive destruction of alveolar bone, mimicking periodontitis. Due to the potential systemic and genetic implications, the diagnosis of neurofibroma requires appropriate medical referral.     

Characteristics of domestically produced siloxane elastomer for making elastic gingival prosthetic device

Gingival prosthetics effectively eliminates esthetic and phonetic disturbances in cases of pronounced gingival recession. Technology for making elastic gingival prosthetic devices of domestically produced siloxane elastomer composition with microwave siloxane vulcanization is described as well as the technique for making combined gingival prosthetics of siloxane composition and colorless plastic.     

Student occupational exposure incidence: perception versus reality

Reports of clinical injuries made to a dental school Office of Occupational Health and Safety at the time of their occurrence were compared to self-reports on a survey for dental students in five classes at various times over their educational careers. The majority of injuries were from needlesticks and mishaps with hand instruments. Underreporting at the time of injury was approximately one-third in the first clinical year and one-half in the final clinical year of the three-year program. Students reported a greater perceived likelihood of injury later in their education than at the beginning but a decreased fear of such injuries. Female students reported more needlesticks and a greater fear of injury than did male students. It is hypothesized that a personal interpretation of the meaning of clinical injuries influences reporting behavior.     

The hyoid bone in malay infants with cleft lip and palate.

OBJECTIVE: To compare morphological and positional variations of the hyoid bone in unoperated infants with cleft lip and palate (CL/P) with those in noncleft infants. DESIGN: Retrospective, cross sectional. PATIENTS AND METHODS: Three-dimensional computed tomography scans were obtained from 29 unoperated CL/P infants of Malay origin aged between 0 and 12 months and from 12 noncleft infants in the same age range. Observations were made and measurements were obtained with a software package developed at the Australian Craniofacial Unit. The sizes of the hyoid bones and the position of the hyoid body and epiglottis in relation to the cervical spine were measured. Anatomical anomalies of the hyoid and prevalence of aspiration pneumonia were also documented. RESULTS: The hyoid bones and epiglottis were found to be located more inferiorly in CL/P infants compared with the noncleft infants. Also, 17% (5/29) of the CL/P infants had nonossified hyoid bodies. CONCLUSION: The results suggest that there are differences in the location and genesis of the hyoid bone in infants with CL/P that warrant further investigation.     

"All I want for Christmas is my two front teeth" (the story behind the song)

During his long and productive career, Donald Yetter Gardner (1913-2004) played various musical instruments, directed church choirs, wrote contemporary church anthems and led many community-sponsored choral events. Additionally, he penned a number of popular spirituals, including "Man Shall Not Live By Bread Alone," and "O Give Thanks Unto the Lord". He was noted for his varied musical accomplishments, but he was best known for composing what was to become an international childrens holiday favorite, "All I Want For Christmas Is My Two Front Teeth".