The prevalence of xerostomia in patients with removable prostheses.

PURPOSE: The objective of this study was to determine the prevalence of xerostomia among patients attending a dental clinic for provision of dentures and to investigate the oral cleanliness in those patients. MATERIALS AND METHODS: Denture-wearing patients who reported dry mouth completed a questionnaire related to xerostomia. Dryness of the mouth was determined by clinical observation. Dental and denture cleanliness was determined using the Modified Debris Index. RESULTS: One hundred twenty patients had xerostomia. Oral cleanliness was generally poor. CONCLUSION: There was a high prevalence of xerostomia in the patient population. A high proportion of subjects had poor oral cleanliness.

Evaluation of stain removal and inhibition properties of eight denture cleansers: an in vitro study.

OBJECTIVES: To determine the ability of eight denture cleansers to remove and inhibit tea-stain build-up on acrylic resin. MATERIALS AND METHODS: In the stain removal study, Perspex(®) (cast heat polymerised resin) specimens previously soaked in saliva were stained using multiple exposures of chlorhexidine and tea solutions. Specimens were exposed for 1 min to one of the eight denture cleansers for five cycles, washed and dried and their optical density read on a uv/vis spectrophotometer at 295 nm. In the stain inhibition study, clear specimens were exposed to saliva followed by cleansers then tea solution, for five cycles. The build-up of stain at each cycle was measured, and differences in optical densities from baseline were calculated. RESULTS: All denture cleansers were significantly more effective than water in removing stain (p < 0.05). There were significant differences in cleaning ability between cleansers (p < 0.001), Dentural(®) and Kleenite(®) were particularly effective. The stain inhibition experiment showed that most cleansers were significantly more effective than water in inhibiting stain (p < 0.05). There were significant differences in inhibition ability between cleansers (p < 0.01). Kleenite(®) and Equate were particularly effective. CONCLUSIONS: All denture cleansers had a capacity to remove stain and most had an inhibitory effect on staining. Kleenite(®) was particularly effective in controlling stain formation.

Two- and three-dimensional accuracy of dental impression materials: effects of storage time and moisture contamination.

Dental impression materials are used to create an inverse replica of the dental hard and soft tissues, and are used in processes such as the fabrication of crowns and bridges. The accuracy and dimensional stability of impression materials are of paramount importance to the accuracy of fit of the resultant prosthesis. Conventional methods for assessing the dimensional stability of impression materials are two-dimensional (2D), and assess shrinkage or expansion between selected fixed points on the impression. In this study, dimensional changes in four impression materials were assessed using an established 2D and an experimental three-dimensional (3D) technique. The former involved measurement of the distance between reference points on the impression; the latter a contact scanning method for producing a computer map of the impression surface showing localised expansion, contraction and warpage. Dimensional changes were assessed as a function of storage times and moisture contamination comparable to that found in clinical situations. It was evident that dimensional changes observed using the 3D technique were not always apparent using the 2D technique, and that the former offers certain advantages in terms of assessing dimensional accuracy and predictability of impression methods. There are, however, drawbacks associated with 3D techniques such as the more time-consuming nature of the data acquisition and difficulty in statistically analysing the data.

The prevalence of dental, facial and head injuries sustained by schoolboy rugby players. A pilot study.

AIM: The aim of the study was to determine the prevalence of dental, orofacial and head injuries and of mouthguard use among schoolboy rugby players. MATERIALS AND METHODS: All members of the first and second XV rugby squads at three secondary schools (two in England and one in Australia) were included in the study. All participants answered a questionnaire that sought information regarding dental, orofacial and head injuries. Statistical differences between groups were determined using chi-square tests for categorical variables and Kruskal-Wallis tests for discrete (count) variables. RESULTS: One hundred and seventy-eight completed questionnaires were returned (100% response rate). One hundred and twenty-five (70%) players reported having sustained at least one injury (range 1-4). Facial injuries were common. Dental injuries were the most prevalent injury: 46 (26%) were reported. Fractured teeth were reported by 20 (11%) players, and avulsed teeth by 7 (4%). There was evidence of a difference between schools in the prevalence of injured players (P=0.014), but among those reporting injuries, there was no difference between schools in the number of injuries (P=0.95). All players said that they used a mouthguard regularly. CONCLUSIONS: Dental, orofacial and head injuries were commonly reported. Dental injuries were the most prevalent type of injury. All players used mouthguards regularly.

Energy absorption and hardness of chair-side denture soft lining materials.

The purpose of this study was to evaluate the hardness and energy absorption properties of four commercially available chairside silicone denture soft lining materials and to compare their properties with those of a heat-polymerized silicone denture liner. The denture lining materials investigated were four auto-polymerising silicone soft liners (GC Reline Soft, Ufigel SC, Elite Soft Relining and Tokuyama Sofreliner S) and a heat-polymerised silicone liner (Molloplast B). The soft liners were processed according to manufacturers' instructions. The specimens for hardness testing were 38 x 38 x 3 mm. The specimens for energy absorption test were 10 x 10 x 3 mm. In each test ten samples of each material were tested. There was strong evidence that Tokuyama Sofreliner S and, to a lesser extent, Ufigel SC, were less stiff and more resilient than Molloplast B. There was also strong evidence that both GC Reline Soft and Elite Soft Relining were harder than Molloplast B, while Ufigel SC and Tokuyama Sofreliner S were softer In conclusion differences existed between hardness and energy absorption properties of the soft lining materials.

Lack of evidence about the effectiveness of the different denture cleaning methods.

DATA SOURCES: Relevant studies were sourced by searching the Cochrane Oral Health Group Trials Register, Cochrane CENTRAL (Cochrane Library), Medline, Embase, LILACS and CINAHL. There were no language restrictions. STUDY SELECTION: Randomised controlled trials (RCT) were considered if they compared any mechanical method (eg, brushing or ultrasound) or chemical (eg, enzymes, sodium hypochlorite, oral rinses or peroxide solutions) in adults over the age of 18 years who wore removable partial dentures or complete dentures. DATA EXTRACTION AND SYNTHESIS: Two independent review authors screened and extracted information from, and independently assessed the risk of bias in, the included trials. RESULTS: Although six RCT were included in this review, the wide range of different interventions and outcome variables did not permit pooling of data in a meta-analysis. Isolated reports indicated that chemicals and brushing appear to be more effective than placebo in reducing plaque coverage and reducing microbial counts of anaerobes and aerobes on complete denture bases. CONCLUSIONS: There is a lack of evidence about the comparative effectiveness of the different denture cleaning methods considered in this review. Few well-designed RCT were found. Future research should focus on comparisons between mechanical and chemical methods, should assess the association between methods, and consider primary variables and costs.

A pilot study of the prevalence of orofacial and head injuries in schoolboy cricketers at eight private schools in England and Australia.

AIMS: The aims of this pilot study were to determine the prevalence of head, face and dental injuries sustained by schoolboys while playing cricket and to compare the prevalence of those injuries in England and Australia. METHODS: A questionnaire that determined distribution and prevalence of orofacial injuries sustained when playing cricket was distributed to all players (n=411) who played cricket in four private schools in England and four private schools in Australia. There was a 100% response rate. RESULTS: Fifty subjects (24.1%) from English schools and 52 subjects (25.5%) from Australian schools reported injury/injuries to the head, face and teeth. Australian cricketers reported more injuries per player. The distribution of injuries between the two countries was similar. Sixteen players had sustained loosened or broken teeth. Two players reported avulsed teeth. CONCLUSION: It was concluded that there was a high prevalence of head and orofacial injuries among the schoolboy cricketers but relatively few dental injuries. The distribution of types of head, face and dental injury in England and Australia were similar.

The prevalence of orofacial pain and tooth fracture (odontocrexis) associated with SCUBA diving.

AIM: To assess the prevalence of orofacial complications associated with SCUBA (self-contained underwater breathing apparatus) diving. Main outcome measures were prevalence of orofacial pain and odontocrexis. METHOD: Two hundred divers at four dive centres on the north-east coast of Australia were asked to complete a questionnaire that requested information regarding diving experience and facial pain and dental symptoms experienced during diving. RESULTS: One hundred and twenty-five completed questionnaires were returned (63% response rate). The prevalence of reported orofacial pain was 44%. Twenty-one per cent reported toothache, 27% sinus pain, 16% jaw pain, and 12% other pain. The prevalence of odontocrexis was less than 1%. Less than 1% had lost a filling when diving. No divers reported a crown or bridge being dislodged during diving. CONCLUSION: Among those who returned questionnaires, orofacial pain in divers was common and odontocrexis was rare.

Oro-facial injuries and mouthguard use in elite female field hockey players.

The objectives of this study were to assess the prevalence of oro-facial injuries, frequency of mouthguard use and players' attitudes towards the use of mouthguards among elite English female field hockey players. All 140 players of the English Hockey Association female Premiere League were asked to complete a questionnaire. Main outcome measures were prevalence of oro-facial injuries, frequency of wearing of mouthguards and attitudes to mouthguard wearing. One hundred and ten completed questionnaires were returned (79% response rate). Facial injuries were common. Nineteen percent had sustained dental injury. Five percent of the respondents had at least one tooth avulsed. Eighty-eight percent of the players said that they owned a mouthguard. Mouthguards were worn regularly during matches by 69% but were used less frequently during training. Six percent thought that mouthguards were ineffective. Eighteen percent of the subjects refused to play if they did not have their mouthguard. Sixty-nine percent of the subjects felt that the mouthguards should be worn compulsorily at all times during the game. The following were finally concluded from the study: oro-facial injuries were commonly reported; 88% of the players possessed a mouthguard; and mouthguards were worn regularly during matches by 69% but were used less frequently during training.

The effectiveness of occlusal splints for sleep bruxism.

DATA SOURCES: Searches were made using the Cochrane Oral Health Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, LILACS (Latin American & Caribbean Health Sciences Literature), Biblioteca Brasileira de Odontologia, and Dissertations, Theses and Abstracts. Hand searches were made of abstracts of particular importance to this review. Additional reports were identified from the reference lists of retrieved reports and from article reviews about treating sleep bruxism. There were no language restrictions. STUDY SELECTION: Randomised controlled trials (RCT) or quasi-RCT were chosen that compared splint therapy concurrently with no treatment, other occlusal appliances, or any other intervention in participants who had sleep bruxism. DATA EXTRACTION AND SYNTHESIS: Data extraction was carried out independently and in duplicate. Validity assessment of the included trials was carried out at the same time as data extraction. Discrepancies were discussed and a third review author consulted. The author of the primary study was contacted when necessary. RESULTS: Thirty-two potentially relevant RCT were identified of which five were eventually included. In these, use of an occlusal splint was compared with palatal splint, mandibular advancement device, transcutaneous electric nerve stimulation, and no treatment. There was just one common outcome (arousal index) which was combined in a meta-analysis. No statistically significant difference between the occlusal splint and control groups were found in meta-analysis. CONCLUSIONS: There is not enough evidence to state that the occlusal splint is effective for treating sleep bruxism. Indication of its use is questionable with regard to sleep outcomes, but there may be some benefit with regard to tooth wear. This systematic review suggests the need for further investigation in more controlled RCT that pay attention to method of allocation, outcome assessment, large sample size, and sufficient duration of followup. The study design must be parallel in order to eliminate the bias provided by studies of crossover type. A standardisation of the outcomes of the treatment of sleep bruxism should be established in the RCT.

Assessment of the oral health related quality of life of patients awaiting initial prosthetic assessment.

The aim of the study was to quantify the impact of oral health problems on the quality of life of patients who were experiencing difficulties with dentures. Two hundred and ten patients who were awaiting an initial specialist assessment appointment were asked to complete the short form Oral Health Impact Profile (OHIP-14). One hundred and sixty three (78%) questionnaires were completed correctly and were analyzed. Overall, the prevalence of impacts was high in all sub-scales, indicating that denture related problems had a negative impact on quality of life of both partially dentate and elderly patients.

Surface modification of an experimental silicone rubber maxillofacial material to improve wettability.

OBJECTIVES: Good wettability of maxillofacial prosthetic materials is important so that a lubricating layer is formed with supporting tissues thus reducing patient discomfort. The purpose of the study was to surface modify an experimental silicone rubber material in order to improve wettability. METHODS: Samples of experimental silicone rubber were surface modified by first argon plasma treatment followed by chemisorption of ethyleneoxy functional silanes. These were compared with the same silicone rubber which had ethyleneoxy functional surfactants incorporated into the polymer matrix. In all cases contact angles, tear strength and water uptake were measured. RESULTS: Surface modified materials had comparable contact angles to surfactant modified silicone rubber all being significantly lower than the unmodified material. Surface modified materials, however, had a significantly higher tear strength and lower water uptake in comparison to surfactant modified materials. CONCLUSIONS: Argon plasma treatment followed by chemisorption of ethyleneoxy functional silanes proved an effective way of improving the wettability of an experimental silicone rubber maxillofacial prosthetic material without altering bulk properties.

Development of a new poly(dimethylsiloxane) maxillofacial prosthetic material.

Maxillofacial prosthetic materials are used to rehabilitate patients suffering from acquired or congenital facial disfigurement. Silicone rubber materials [poly(dimethylsiloxane) rubbers] are the materials of choice. However, current formulations have inadequate mechanical properties, in particular, tear strength. The purpose of this study was to formulate a new poly(dimethylsiloxane) material with improved mechanical properties in comparison to commercially available materials. The formulations developed were based on condensation chemistry containing a hydroxy-end-blocked poly(dimethylsiloxane), hydrophobic silica filler, silane cross-linking agents, and a tin catalyst. The following parameters were varied in order to formulate improved materials: (a) bimodal polymeric mix (i.e., ratio of high- and low-molecular-weight polymers); (b) silica filler type and quantity. By varying these parameters a formulation was developed with a base polymer mix of 80%:20% high- to low-molecular-weight polymers into which 20% w/w filler was added. This formulation had a tear strength of 22.23 +/- 1.6 m N/mm compared to the commercial materials having tear strengths in the range 4.53-17.63 N/mm.

Analysis of the properties of silicone rubber maxillofacial prosthetic materials.

OBJECTIVES: Maxillofacial prosthetic materials are used to replace facial parts lost through disease or trauma. Silicone rubbers are the materials of choice, however it is widely accepted that these materials do not possess ideal properties. The objective of this study was to assess the properties of a range of commercially available silicone rubber maxillofacial materials and make recommendations for improvements. METHODS: Specimens of five commonly used maxillofacial materials were prepared in dental flasks according manufacturers instructions. Tear strength, tensile strength, percentage elongation, hardness, water absorption and water contact angles were determined for each material. RESULTS: The tear strength of Factor II, Cosmesil HC and Nusil were all comparable and significantly higher than Cosmesil St and Prestige (p<0.001). Nusil had a significantly higher tensile strength and elongation in comparison to the other materials (p<0.001) and Cosmesil St and Cosmesil HC were significantly harder (p<0.001). Factor II was significantly less wetted and Prestige and Cosmsesil St had a significantly higher water absorption in comparison to the other materials. CONCLUSIONS: None of the commercially available silicone rubber materials possessed ideal properties for use as a maxillofacial prosthetic material. Factor II, however, showed more favourable properties due to it's high tear strength, softness and ease of manipulation.

Some variables influencing the bond strength between PMMA and a silicone denture lining material.

PURPOSE: The purpose of the present study was to investigate the effect of roughening the denture base surface on the tensile and shear bond strengths of a poly(dimethylsiloxane) resilient lining material (Molloplast-B) bonded to a heat-cured acrylic resin denture base material. These measured bond strengths were compared to those obtained by packing the soft lining material against poly(methyl methacrylate) (PMMA) denture base acrylic resin dough. MATERIALS AND METHODS: Three groups of 10 specimens each were constructed for both tensile and shear tests. In the first group, Molloplast-B was packed against cured PMMA denture base surface. In the second group, Molloplast-B was packed against cured PMMA denture base whose surface had been roughened with an acrylic bur. In a third group, Molloplast-B was packed against PMMA denture base acrylic resin dough. RESULTS: Molloplast-B exhibited significantly higher tensile and shear bond strengths when packed against acrylic resin dough. Roughening the denture base surface prior to the application of Molloplast-B had a statistically significant weakening effect on tensile bond strength compared with the smooth surface and the acrylic resin dough. For the shear bond strength, roughening the surface produced a nonsignificant increase compared with the smooth surface, but the bond was weaker than when packed against acrylic resin dough. CONCLUSION: Significant differences in tensile and shear bond strength were recorded between the three methods used to bond Molloplast-B to denture base material.