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J Jansma

Publications and source records attributed to J Jansma.

26 records · Page 2Linked to original sources

A survey of prevention and treatment regimens for oral sequelae resulting from head and neck radiotherapy used in Dutch radiotherapy institutes.

Radiation treatment plays an important role in the management of head and neck cancer. Unfortunately several radiation-induced side effects may occur including mucositis, hyposalivation, radiation caries, trismus and osteoradionecrosis. It is generally accepted that most side effects can be prevented or reduced in severity. The purpose of this investigation was to make a survey of the prevention and treatment regimens for oral sequelae resulting from head and neck radiotherapy applied in all radiotherapy institutes in the Netherlands, and to evaluate the differences in these regimens. In all Dutch centers (n = 20) in which irradiation of head and neck cancer patients is performed, members of the staff responsible for prevention and treatment of oral side effects were interviewed. Questions referred to composition of the dental team, screening and care pre-irradiation, care during irradiation, and care post-irradiation. There appeared to be a great diversity in the preventive approach of the head and neck cancer patient in Dutch radiotherapy institutes. The most comprehensive counseling was performed by those centers in which a dental team was active, particularly when an oral hygienist was a member of such a team. The diversity is among others based on lack of well-defined guidelines in many centers, the spread of a relatively small patient group over a rather large number of centers, absence of a dental team in some centers, absence of an oral hygienist in some dental teams, and the observation that a rather large number of patients were not referred, or not timely referred to the dental team. There seems to be a need for the development of a general protocol for the prevention of oral complications applicable in all centers.

Dental Caries↗

[Cause, effects and treatment of hyposalivation].

Adverse effects of drugs, radiotherapeutic treatment of head and neck tumors and Sjögren's syndrome are common causes of hyposalivation. The resulting sequelae include oral dryness, burning mouth, impeded oral functions, nocturnal oral discomfort and an increased incidence of rampant caries and oral infections. Causal therapy is only occasionally applicable. The main causes, consequences and management of hyposalivation are described.

Dental Caries↗

[Xerostomia-related dental caries].

The initiation and prevention of xerostomia-related dental caries were studied using an in situ model. The morphology of induced carious lesions was compared with that of natural xerostomia-related dental caries. Both natural and induced xerostomia-related dental caries showed the same patterns of decay. Using the in situ model three preventive procedures were tested: neutral F gel applied every second day or weekly, and a daily rinse with a fluoride mouthwash for a period of six weeks. Application of fluoride gel or the use of the fluoride mouthrinse resulted in significant inhibition of the demineralization process. Of the procedures evaluated fluoride gel applied every second day was the most effective in preventing the onset of xerostomia-related dental caries.

Administration, Topical↗

Effect of X-ray irradiation on the permeability of bovine dental enamel.

To estimate permeability properties of bovine dental enamel, complex impedance measurements and radioisotope diffusion experiments were carried out before and after X-ray irradiation (single dose, 72 Gy) of enamel specimens. Neither impedance measurements nor diffusion experiments showed significant changes in permeability.

Animals↗

In vivo study on the prevention of postradiation caries.

Postradiation caries is usually prevented by the application of topical fluorides (F) at high concentrations. The aim of this study was to develop an optimal preventive program for postradiation caries by evaluating the effects of F concentration and application procedures in subjects with radiation-related xerostomia. Six ground enamel slabs were mounted on each side of the lower denture of each of 7 xerostomia patients. Four procedures were used: no F exposure (control), neutral F gel applied every 2nd day or weekly, and a daily rinse with a F mouthwash for a period of 6 weeks. The enamel slabs were analyzed at weekly intervals by scanning optical monitoring, longitudinal microradiography, and scanning electron microscopy. In addition, hardness measurements were performed on the slabs. F analyses of the enamel slabs were done prior to their insertion in the appliances and after 6 weeks of intraoral exposure. In the control experiments severe demineralization of enamel occurred within 6 weeks. Application of F gel or the use of the F mouthrinse resulted in a significant inhibition of the demineralization process. Of the procedures evaluated, F gel applied every 2nd day was the most effective in preventing the onset of postradiation caries.

Aged↗

The effect of X-ray irradiation on the demineralization of bovine dental enamel. A constant composition study.

In this study the effect of X-ray irradiation on demineralization of bovine dental enamel in vitro was investigated. Enamel specimens were irradiated with 72 Gy and subsequently demineralized (140 h) under reproducible constant composition conditions at pH = 5 in the presence of methylhydroxydiphosphonate (MHDP). Microhardness measurements after demineralization without MHDP showed significant differences (p less than 0.001) between irradiated and nonirradiated enamel specimens; no significant differences were found in the presence of MHDP. Quantitative microradiography showed that both mineral loss and lesion depth were significantly lower (p less than 0.001) for the irradiated enamel specimens compared with the nonirradiated ones. Surface layer formation was observed in irradiated enamel demineralized in a solution without MHDP. It was shown that X-ray irradiation decreased the enamel acid solubility in vitro.

Animals↗

A model to investigate xerostomia-related dental caries.

The aim of this study was to develop an in vivo model in which onset, progression, and prevention of xerostomia-related dental caries can be studied. The progress of the caries process was investigated on ground and polished human enamel blocks placed in the lower denture of 7 edentulous subjects suffering from xerostomia. During a period of 6 weeks the samples were analyzed at weekly intervals by means of scanning optical monitoring, scanning longitudinal microradiography, scanning electron microscopy, and hardness measurements. Although the indentation length increased significantly within 2 weeks, no demineralization could be yet observed with scanning optical monitoring, longitudinal microradiography, and electron microscopy in most samples. Starting from the 3rd week a progressive demineralization could be observed by all methods. The mineral loss (hydroxyapatite) in the 3rd week was 0.0126 kg.m-2 (median) which increased to 0.0761 kg.m-2 after 6 weeks. Scanning electron microscopy showed a destruction which resembled that of natural xerostomia-related dental caries. From this study it may be concluded that the in vivo model developed is suitable for studying onset, progression, and prevention of xerostomia-related dental caries.

Aged↗