Enhancement of bone ingrowth into collagen/HA composite implants using e-PTFE membranes.

The objective of this investigation was to study the effectiveness of expanded polytetrafluoroethylene (e-PTFE) membranes for enhancement of bone ingrowth through subperiosteally implanted collagen/HA composite blocks. Twelve rabbits aged 12-15 months served as the experimental animals in this study. Two compressed Collagen/HA composite blocks in the shape of two attached cylinders of different diameters were inserted into two defects of each rabbit calvarium, the smaller cylinder being intrabony, the larger subperiosteal in location. One of the two implants was covered with non-resorbable e-PTFE membrane. The other implant was left uncovered. Specimens were obtained at 4, 8, and 12 weeks. While the implant specimens on the membrane side showed progressive bone formation between and around HA particles at the subperiosteal extrabony locations, the HA particles on the non-membrane side were surrounded and separated by dense fibrous tissue. At intraosseous sites, HA particles were surrounded by new bone throughout the defect on the membrane side, but new bone formation occurred only along the periphery on the non-membrane side. It appears that guided tissue regeneration may be used to enhance new bone formation around and between subperiosteally implanted HA particles.

Morphologic effects of glycerol on the mental nerve.

OBJECTIVES: In recent years, injection of pure glycerol has been used successfully for the treatment of trigeminal neuralgia. However, the mode of action of this therapy remains unclear. The present experiment was undertaken to examine histologically the morphologic changes produced by extraneural injections of pure glycerol into the dog mental nerve. STUDY DESIGN: Under direct vision, glycerol was injected extraneurally into the mental foramen on one side of the lower jaw of each of nine dogs. Physiologic saline solution was the control on the contralateral side of each animal. Animals were killed at 1, 3, and 7 days after the application of glycerol, and the mental nerve specimens were examined by light microscopy. RESULTS: Results showed that extraneural application of pure glycerol in the vicinity of the dog mental nerve is not associated with structural changes. No signs of nerve degeneration or other morphologic changes were observed for any of the experimental and control specimens in any of the time intervals studied. CONCLUSIONS: It can be concluded that despite the encouraging clinical results related to extraneural application of pure glycerol for treatment of trigeminal neuralgia, glycerol produces its effect without inducing any morphologic or destructive changes in the peripheral nerve. A probable explanation of the temporary clinical effectiveness of glycerol in relieving trigeminal neuralgia is discussed.

Modified bovine type I collagen membrane as a wound graft material in oral surgery (an experimental study).

The use of collagen biomaterials in various types, structures and forms to aid in wound healing and in reconstructive surgery has been reported in several occasions in the literature. This paper evaluates the biocompatibility and effectiveness of a modified bovine type I collagen membrane as a graft material in experimental oral wounds in dogs. 2.5 x 2.5 cm wounds were prepared bilaterally in the labial mucosa of nine dogs. Bovine type I atelopeptide reconstituted collagen membrane was placed over the surgery site on one side of the labial mucosa. The contralateral sides served as controls. Clinical and histopathologic evaluation were done at 1, 2 and 3 weeks post-operatively, comparing the experimental side with the control side. Results demonstrated an improved rate of wound healing on the experimental side. The collagen membrane had a topical hemostatic effect at the time of its application and did not cause any adverse reaction post-operatively. It is concluded that the modified collagen membrane used in this study is biologically acceptable to the oral mucosa and is, from the clinical point of view, an excellent wound graft material. The clinical utilization of these collagen sheets offers exciting applications in the field of oral surgery.

Panoramic radiographic study of mental foramen locations in Saudi Arabians.

A panoramic radiographic study was carried out on 404 dentate Saudi Arabians, to locate positions of the mental foramen. Results show that 83.7% of the mental foramen locations occurred in the interdental space between the mandibular premolars and apical to the mandibular second premolar. 9.35% occurred posterior to the mandibular second premolar, and 6.95% occurred apical/anterior to the mandibular first premolar. In female Saudis, the most common location of the mental foramen was apical to the mandibular second premolar (45.9%), while the most common location in male Saudis was the interdental space between the mandibular premolars (45.5%). Asymmetry of the mental foramen location, which was observed in 15.6% of the cases, was observed more often in males (17.9%) than in females (12.3%).

Periodontal treatment needs among Saudi Arabian adults and their relationship to the use of the Miswak.

The main aims of this study were, first, to estimate the need for periodontal care among adult residents of Saudi Arabia using the community periodontal index of treatment need (CPITN) and, second, to quantify the relationship between the frequency of using the 'Miswak' and the need for periodontal care. The Miswak is a stick made from the roots of the Arak tree (Salvadora persica) and is used for oral hygiene purposes by many cultures. A total sample of 480 adults aged 35 to 44 years and 65 years and older from the cities of Mecca and Jeddah was included in the study. The findings indicate that the level of need for periodontal care in the sample chosen is low when compared with the findings of similar studies undertaken in other countries. The frequent use of the 'Miswak' was associated with a lower need for treatment.

Caries prevalence and treatment need amongst children in an Arabian community.

A total of 1400 Saudi Arabian children in age groups 6-12 and 15 yr in private and public schools were examined for dental caries and treatment need in the cities of Jeddah (less than 0.30 ppm fluoride in drinking water), Rabagh (0.77 ppm F-) and Mecca (2.47 ppm F-). The mean dmft in 6-yr-olds in private schools in Jeddah was 2.9 compared with 6.3 in public schools (P less than 0.001). The d component accounted for 65% of the total dmft in private schools and 76% in public schools in Jeddah. The mean dmft values in private and public schools in Rabagh were 1.5 and 2.8 respectively and 2.7 and 2.8 in Mecca; the d component accounted for approximately 65% in all groups. The figures for permanent teeth in 12- and 15-yr-olds show similar trends with caries levels being the highest in public schools in Jeddah; approximately 60% of the total DMFT was attributable to the D component in both school types in all three cities. Most of the treatment required in all three cities comprised one- or two-surface fillings. The need for treatment was significantly higher in public schools.

The relationship between the indications for the surgical removal of impacted third molars and the incidence of alveolar osteitis.

Six hundred forty-two impacted third molars were surgically removed in 412 patients. Before surgery, each patient was assessed clinically and radiographically, and the reason for the removal of each tooth was specifically recorded. One hundred eighty-two of the impacted teeth were removed for prophylactic reasons and 460 for therapeutic reasons. As much as possible, standardization of the operating procedure and environment, and of the preoperative and postoperative regimens was observed. After surgery, each case was followed to determine the absence or presence of signs and symptoms of alveolar osteitis. It was found that several factors seem to contribute to the development of alveolar osteitis; however, the most significant related finding was that the reason for the extraction, that is, whether the extraction was undertaken for therapeutic or prophylactic reasons.

Dental caries in children residing in communities in Saudi Arabia with differing levels of natural fluoride in the drinking water.

Children aged 6, 12 and 15 years were examined for dental caries in three cities in Saudi Arabia, with varying levels of naturally occurring fluoride in the drinking water; Jeddah (less than 0.3 ppm), Rabagh (0.8 ppm) and Mecca (2.5 ppm). For each age group, caries levels were considerably higher in Jeddah than in Rabagh or Mecca. Occlusal surfaces were most frequently affected. Children attending public schools experienced a considerably higher caries prevalence than those attending private schools. All age groups had high levels of untreated dental decay. Preliminary results indicate that residents of Mecca exercise unacceptable levels of dental fluorosis.

Developing a research team in dental epidemiology in Saudi Arabia: a collaborative project between King Abdulaziz University, Jeddah and University College, Cork, Ireland.

The Paper describes the setting-up of a Collaborative Project between King Abdulaziz University, Jeddah, Saudi Arabia, and University College, Cork, Ireland. The objective was to develop a Research Team in Oral Health Services Research in Saudi Arabia and to conduct Pre-Fluoridation Oral Health Studies.

Relationship between attitudes, behaviour and levels of dental caries among 15-year-old Saudi Arabian and Irish children.

In 1987, the first major dental epidemiological study was carried out in the Kingdom of Saudi Arabia, with the help and cooperation of the WHO Collaborating Centre for Oral Health Services Research, University Dental School, Cork, Ireland. As part of the project, the 15-year-old age group underwent an interview survey in order to ascertain if oral health attitudes and behaviour were related to oral health outcomes, as measured by the mean DMFT for the group. In common with the findings of similar studies in other countries, including Ireland, little or no correlation between the sociological variables and oral health outcomes was apparent. Such findings, however, simply highlight the unreliability of cross-sectional designs when attempting to isolate a relationship between a cumulative condition, such as dental caries, and parameters which clearly change with time. The differences found in the oral health behaviour of the Saudi Arabian and Irish 15-year-old children is particularly noticeable in respect of the frequency of intake of sweet foods and drinks.