[Bone augmentation of the extremely atrophic anterior mandible, using allogeneic block grafts, via submental approach].

Edentulous patients with advanced resorption of the mandible (atrophic mandible) suffer major discomfort when using dentures. Furthermore, placing dental implants is impossible due to lack of sufficient bone volume. In the past, several methods of bone grafting to the anterior mandible have been proposed. Most of them were unpredictable in either the short or long-term. In 2002 a technique for bone grafting of the anterior mandible via a submental approach was published. A wide reflection of the soft tissue was followed by implant placement. Autogenous particulate posterior iliac crest bone graft was used. The presence of the implants did not allow for contraction of the soft tissue and bone resorption. The addition of bone volume to the chin improved the facial aesthetics of the patients due to a fuller appearance of the chin and tightening of the skin of the neck. The submental approach changes the spatial orientation of the surgeon and placement of implants in the correct location and angle become challenging. Placement of the implants too far buccally was a prosthetic problem. A major disadvantage of autogenous bone grafting is the necessity to operate a donor site. The increasing experience in use of allogenic bone grafts with resorbable collagen membranes, allowed us to modify the submental approach for bone grafting of the anterior atrophic mandible, avoiding a donor site surgery. We chose to perform the bone graft as a first stage surgery, in which, via a submental approach allogenic bone blocks were adapted and fixated to the anterior mandible with titanium screws, xenograft and resorbable collagen membranes were used. A few months (>4) were allowed for graft consolidation and then a second stage surgery was performed, via an intraoral approach dental implants were placed. In this way we avoided loss of orientation and had a familiar setting for implant location and angulation. Five patients with atrophic mandibles were treated using this surgical protocol. Based on cone beam CT imaging, average bone height in the anterior mandible prior to treatment was 5.52 mm. After bone graft, the average gain in bone height was 12.74 mm. No major post-operative complications were noted. After bone graft consolidation, 4 or 5 dental implants were placed, most of the implants used were longer than 11.5 mm. 22 implants were placed, out of which 21 integrated (95.5%). Some of the patients were rehabilitated with overdentures and locators and some with PFM bridges. All patients were followed up for more than a year and no implant failure was recorded. Bone grafting to the anterior mandible using allogenic blocks with collagen membranes via a submental approach with second stage implant placement seems to be a viable solution for rehabilitation of the atrophic mandible.

The effect of mucosal cuff shrinkage around dental implants during healing abutment replacement.

Soft tissue shrinkage during the course of restoring dental implants may result in biological and prosthodontic difficulties. This study was conducted to measure the continuous shrinkage of the mucosal cuff around dental implants following the removal of the healing abutment up to 60 s. Individuals treated with implant-supported fixed partial dentures were included. Implant data--location, type, length, diameter and healing abutments' dimensions--were recorded. Mucosal cuff shrinkage, following removal of the healing abutments, was measured in bucco-lingual direction at four time points--immediately after 20, 40 and 60 s. anova was used to for statistical analysis. Eighty-seven patients (49 women and 38 men) with a total of 311 implants were evaluated (120 maxilla; 191 mandible; 291 posterior segments; 20 anterior segments). Two-hundred and five (66%) implants displayed thick and 106 (34%) thin gingival biotype. Time was the sole statistically significant parameter affecting mucosal cuff shrinkage around dental implants (P < 0.001). From time 0 to 20, 40 and 60 s, the mean diameter changed from 4.1 to 4.07, 3.4 and 2.81 mm, respectively. The shrinkage was 1%, 17% and 31%, respectively. The gingival biotype had no statistically significant influence on mucosal cuff shrinkage (P = 0.672). Time required replacing a healing abutment with a prosthetic element should be minimised (up to 20/40 s), to avoid pain, discomfort and misfit.

[Nutraceuticals in the combat against oral cancer].

Head and neck squamous cell carcinoma (HNSCC), the eighth most common cancer worldwide, accounts for approximately 600,000 new cases per year. The mobile tongue is the most common site for oral cancer and is associated with a poorer survival than other HNSCC sites. Standard therapeutic strategies have failed to significantly improve survival rates that have remained around 50% over the past four decades. In the last decade intense investigations on oral cancer highlighted the mandatory role of the tumor microenvironment (TME), in addition to the genetic aberrations and molecular biology changes within the cancer cells. Furthermore, the molecular crosstalk between cancer cells and TME components (i.e., cancer-associated fibroblasts, inflammatory pro-tumorigenic cells, etc.) has a crucial role in growth, invasion, spread and metastases of the cancer cells and consequently leads to poor prognosis. Recent studies suggest that plant-derived dietary agents nutraceuticals, especially curcumin and green tea, have the advantage to combat both malignant cells and TME components, unlike standard anti-cancer protocols that target only cancer cells. However, due to a very low bioavailability, nutraceuticals do not currently constitute an integral part of these protocols. Ongoing developments in nanotechnology for improved delivery are expected to overcome their challenging pharmacokinetics.

The influence of partial implant-supported restorations on chewing side preference.

This study aimed at determining whether the individual's chewing side preference is affected by local effects, produced by the presence of implant-supported restorations. The test group included 81 patients with partial implant-supported prosthesis. The control group included 108 subjects with no implants. All subjects went through a series of laterality tests for chewing and tasks (hand, foot, eye and ear) side preference. The preferred chewing side (PCS) was determined by observing the first stroke of the chewing cycle during chewing a gum. A positive and significant correlation between the chewing side preference and the subject's sidedness during the different tasks was examined, by performing four Phi correlation tests for: chewing and handedness(r = 0·54; P < 0·001); chewing and footedness (r = 0·49; P < 0·001); chewing and eyedness (r = 0·65; P < 0·001) and chewing and earedness (r = 0·66, P < 0·001). Of the subjects, 78·3% preferred the right side for chewing, 19·1% preferred the left and 2·1% had no clear side preference. There was no statistical difference in chewing side preference distribution between genders. The distribution of chewing side preference was not significantly affected by the location of missing teeth or implants. In conclusion, implant placement will not affect PCS. Therefore, information on chewing side preference should be part of the routine preoperative examination for implant-supported restorations to provide a better treatment plan in those cases that the implant-supported restoration will be on the PCS.

Analysis of load transfer and stress distribution by splinted and unsplinted implant-supported fixed cemented restorations.

Controversy remains over the rehabilitation of implant-supported restorations regarding the need to splint adjacent implant-supported crowns. This study compared the effects of simulated occlusal loading of three implants restored with cemented crowns, splinted versus unsplinted. Three adjacent screw-shaped implants were passively inserted into three holes drilled in a photo-elastic model. Two combinations of cemented restorations were fabricated; three adjacent unsplinted and three adjacent splinted crowns. Strain gauges were connected to the implant necks and to the margins of the overlaying crowns. Fifteen axial static loads of 20-kg loadings were carried out right after each other via a custom-built loading apparatus. Strain gauges located on the implant neck supporting splinted restoration demonstrated significantly (P < 0.001) more strain (sum of strains = 3348.54 microstrain) compared with the single crowns (sum of strains = 988.57 microstrain). In contrast, significantly (P < 0.001) more strain was recorded on the strain gauges located on the restoration margins of the single crowns (sum of strains = 756.32 microstrain) when compared with splinted restorations (sum of strains = 186.12 microstrain). The concept of splinting adjacent implants to decrease loading of the supporting structures may require re-evaluation. The clinical relevance of these findings needs further investigation.

Assessing the levels of immunoglobulins in the saliva of diabetic individuals with periodontitis using checkerboard immunodetection.

BACKGROUND: Current methods for determining salivary antibodies are cumbersome for large-scale screenings. OBJECTIVES: To test checkerboard immunodetection for monitoring salivary antibodies and to profile them in diabetic individuals with periodontitis. METHODS: Salivary anti-Porphyromonas gingivalis, anti-Actinobacillus actinomycetemcomitans and total IgA levels of 10 individuals were compared using checkerboard immunoblotting and enzyme-linked immunosorbent assay (ELISA). RESULTS: Close correlation between both methods was found in anti-P. gingivalis IgA and total IgA, but not in anti-A. actinomycetemcomitans IgA, because of high background levels in ELISA. Thereafter, checkerboard immunodetection was used to compare salivary antibodies of 20 adult type II diabetic with 32 non-diabetic individuals with (n=22) or without (n=10) periodontitis. Patients with periodontitis (regardless of their diabetic condition) expressed increased levels of total IgA in both whole and parotid saliva, but reduced levels of anti-A. actinomycetemcomitans IgA in whole saliva. Consequently, the proportion of anti-A. actinomycetemcomitans IgA in the total IgA was lower in saliva of patients with periodontitis compared with healthy controls. CONCLUSIONS: Checkerboard immunodetection was reliable and economical for screening saliva samples for multiple antibody reactions. Our results support previous reports which suggested that patients with periodontitis are able to secrete high levels of salivary Ig, but are hampered in targeting their salivary response toward A. actinomycetemcomitans.

Age-dependent deficiency in saliva and salivary antibodies secretion in Down's syndrome.

OBJECTIVE: Down's syndrome (DS) individuals suffer from an increased susceptibility to infections. Here, we assessed age-related changes in the salivary-specific humoral immunity of DS subjects. DESIGN: Parotid and whole saliva were collected from a young group of DS (YDS, n=30, 23.3+/-4 years), an older group of DS individuals (ODS, n=10, 51.9+/-8 years) and compared to two age-matched groups of healthy volunteers--a young group (YC, n=29, 22.8+/-5 years) and an older group (OC, n=10, 48.4+/-9 years). The levels of total IgA, and specific antibodies to three common oral pathogens (Porphyromonas gingivalis, Actinobacillus (Aggregatibacter) actinomycetemcomitans and Streptococcus mutans) were analysed. RESULTS: The limited increases in IgA concentrations could not compensate the dramatic reduction in the salivary flow rate observed in DS individuals. Therefore, the median secretion rates of the specific antibodies in whole and parotid saliva were 70-77% and 34-60% (respectively) lower in YDS individuals as compared to YC and farther 77-100% and 75-88% (respectively) lower in ODS compared to YDS. In contrast, the antibody secretion rates were similar for parotid saliva, or even increased for whole saliva of OC, compared with YC. Consequently, a dramatic cumulative extreme reduction (>92%) in the bacterial specific salivary antibodies differentiated the adult DS individuals from to their age-matched controls. CONCLUSIONS: Our results indicate a severe immunodeficiency in the secretion rate of the specific salivary IgA response of in DS individuals which intensifies with age.

[Orthodontic anchorage in the era of osseointegration].

The introduction of the concept of osseointegration had a profound impact on dentistry of the 20th century. The idea of using this concept in orthodontics already started in the late 70th. There demand for achieving optimal esthetic results in a minimal treatment time, and the significant increase in the number of adult orthodontic patients, made osseointegration an essential adjunct to orthodontic therapy. The use of osseintegrated anchorage devices helps the clinician to overcome one of the most limiting aspects of orthodontic therapy--inadequate anchorage. In the last years a large variety of osseointegrated anchorage devices have been developed and introduced in orthodontics. The purpose of the present article is to present several cases that illustrate how to solve anchorage problems by the using the principles of osseointegration and mechanical retention. The selection of the most appropriate anchorage device for each specific case will be emphasized.

Salivary LL-37 secretion in individuals with Down syndrome is normal.

Antimicrobial peptides play an important role in the innate immune response. Deficiency in salivary LL-37 antimicrobial peptide has been implicated in periodontitis in patients with morbus Kostman syndrome. Down syndrome is associated with periodontitis, diminished salivary flow, and salivary immunoglobulin deficiency. In the present study, levels of LL-37 and its hCAP18 precursor were measured in saliva samples from young individuals with Down syndrome and compared with levels in those from age-matched healthy controls. LL-37 and human cathelicidin antimicrobial protein (hCAP18) were detected in whole but not in parotid saliva. hCAP18 was more abundant than LL-37. The concentrations of salivary hCAP18 and LL-37 were found to be higher in individuals with Down syndrome than in healthy controls, but their secretion rates were similar. We concluded that, while the adaptive immunity of individuals with Down syndrome is impaired at the oral mucosa, the secretion rate of the LL-37 component of the innate immune system is normal.

The outcome of a preventive dental care programme on the prevalence of localized aggressive periodontitis in Down's syndrome individuals.

BACKGROUND: Periodontal disease in Down's syndrome (DS) individuals develops earlier and is more rapid and extensive than in age-matched normal individuals. The present study evaluated a group of DS patients, who had been participating in a 10-year preventive dental programme, for the impact of the programme on their periodontal status. METHODS: Thirty DS patients (mean age 23.3 +/- 4 years) were compared with 28 age-matched healthy controls (mean age 22.8 +/- 5 years). The hygiene level, gingival condition and periodontal status (periodontal probing depth, clinical attachment level and radiographic alveolar bone loss) were determined. RESULTS: In spite of similar oral hygiene and gingival measures, DS patients, as opposed to the control ones, had a severe periodontal disease. The prevalence, extent and severity of periodontitis in the DS group were significantly greater than in the control group. The teeth most commonly and severely affected were the lower central incisors and the upper first molars. DS patients lost significantly more teeth due to periodontitis. CONCLUSIONS: The clinical and radiographic picture found in the present DS group is characteristic of localized aggressive periodontitis. Within the limitations of this study, it seems that the preventive dental programme had no effect on periodontal destruction progression of localized aggressive periodontitis in DS individuals and that impaired oral hygiene plays a relatively minor role in the pathogenesis of this disease. Future controlled studies are needed to assess the effectiveness of different preventive dental programmes in preventing the progression of periodontitis in DS patients.

The clinical effectiveness of 6 mm diameter implants.

BACKGROUND: Five- and 6 mm diameter screw-type endosseous implants have been used for the last decade. While some studies have reported very promising results (94% to 98% success rate), others have demonstrated survival rates below those clinically acceptable (75% to 87%). Moreover, such implants have been associated with increased cervical bone resorption and thread exposure. METHODS: Between June 1999 and July 2003, 43 patients received treatment with 6 mm diameter tapered hydroxyapatite (HA)-coated implants. A total of 45 implants were placed. All patients were recalled annually after implant exposure. One patient was lost to follow-up after 1 year. Forty-four implants were evaluated at the recall examinations. All implants supported a fixed prosthesis; in the majority of patients (35 implants), it was a single-tooth fixed prosthesis. The mean loading time was 23.4 months (range, 1 to 54 months). RESULTS: No implants were lost during the loading period. The overall survival rate was 100%. Crestal bone remodeling was examined using periapical radiographs. After a mean of 23.4 months in function, only one implant presented bone loss beyond the first thread. CONCLUSIONS: This study showed that high survival rates can be obtained after prosthetic treatment with 6 mm-wide tapered HA-coated implants. Long-term prospective studies are needed to confirm these results.

Patients' perceptions of recovery after surgical exposure of impacted maxillary teeth treated with an open-eruption surgical-orthodontic technique.

This study assessed patient perceptions of immediate post-operative recovery after the surgical exposure of impacted maxillary teeth with an open-eruption technique. Thirty patients (24 females and six males) underwent surgical exposure of 39 impacted maxillary teeth using this technique. After surgery the patients were contacted by telephone daily for 7 days, to complete a health-related quality of life (HRQOL) questionnaire, which assessed their perception of recovery in four main areas: pain, oral function, general activity, and other symptoms. Severe pain was reported by 30 per cent of the patients in the first post-operative day (POD 1), which declined to 6.7 per cent by POD 6. Consumption of analgesics declined gradually over the post-operative days (POD 1: 80 per cent, POD 7: 20 per cent). Difficulty in eating required 5 days to reach minimal levels; enjoying everyday food, 2.5 days; school attendance, limitations in daily routine, swallowing, and speech, 2 days each; swelling, bad taste/smell, 1.5 days each; within 1 day all other measures attained minimal levels. The need for bone removal during the exposure resulted in delayed recovery with regard to the ability to eat. In general, females reported delayed recovery for pain. The present data may serve as basic guidelines against which future studies which assess post-operative management of patients after surgical exposure of impacted teeth by an open-eruption technique may be compared.

[The use of autogenous block graft for augmentation of the atrophic alveolar ridge].

The use of osseointegrated implants has become a standard treatment option in modern dental rehabilitation. Adequate bone quantity and quality is a prerequisite for good esthetic and biomechanical result. Alveolar ridge defects can be the result of trauma, periodontal diseases or other pathologic conditions. In these cases, alveolar ridge augmentation is needed if endosseous implants are to be used. While xenografts, alloplastic bone grafts and allografts have been proposed for alveolar ridge augmentation, the use of autogenous bone grafts represents the "gold standard" for bone augmentation procedures. Either intraoral or extraoral sites may be considered for donor sites. Although the iliac crest is the most common donor site in maxillofacial reconstruction, the mandibular symphysis or ramus offer important advantages like avoidance of general anesthesia, convenience due to the proximity between the donor site and the augmentation site and avoidance of cutaneous scar. Bone harvested from intraoral donor site is less associated with resorption when compared with iliac bone because membranous grafts revascularize more quickly than endocondral bone grafts. The main disadvantage of the intraoral donor sites is the limited amount of available bone. Alveolar ridge augmentation using autologous bone block, can be done during implant placement or staged with implant placement, after bone graft healing. In the staged technique, a better implant positioning and the use of wide diameter implants are possible. The overall implant success is higher in the staged technique. Alveolar ridge augmentation using autogenous block graft is a predictable way of treatment, for the atrophic alveolar ridge before implant placement.

Parotid salivary immunoglobulins, recurrent respiratory tract infections and gingival health in institutionalized and non-institutionalized subjects with Down's syndrome.

BACKGROUND: The purpose of the present study was to evaluate the possible correlation between recurrent respiratory infections (RRIs), gingival health and the secretion rates of salivary immunoglobulins (Igs) in institutionalized (I) and non-institutionalized (NI) individuals with Down's syndrome (DS). METHODS: Stimulated parotid saliva was collected from nine I and 14 NI subjects with DS. Salivary flow rate, secretion rates of total salivary IgM, IgG and IgA, and the incidence of RRIs were determined. Gingival health was recorded by using the plaque index, the gingival index and the percentage of bleeding surfaces (BS). RESULTS: The mean salivary flow rate and parotid Ig secretion rates in the I group were 25% of those of the NI group. The prevalence of RRIs in the I group was more than twice that in the NI group. Oral hygiene and gingival health were significantly better in the NI group. CONCLUSIONS: The lower parotid Ig secretion rates in I individuals with DS might be a possible factor involved in their susceptibility to recurrent infections compared to NI subjects with DS.

Severe impairment of secretory Ig production in parotid saliva of Down Syndrome individuals.

Infections associated with Down Syndrome (DS) are prevalent in the mucosal-gastrointestinal and respiratory systems, for reasons that are uncertain. The purpose of the present study was to assess the levels of parotid salivary immunoglobulins (Ig) in a group of DS individuals as a possible factor in the susceptibility of mucosal surfaces to infections. Twenty-nine DS and 10 age- and sex-matched healthy individuals were included. Salivary flow rate and IgA, IgG, and IgM concentrations were recorded. The secretion rates of IgA and IgG were diminished by 83% (p < 0.001) and 75% (p = 0.05), respectively, whereas the secretion rate of IgM was not statistically significantly lower. Analysis of the data suggests that DS individuals are immunodeficient in the humoral mucosal immune response. This may explain, in part, the high incidence of recurrent infections in target organs of the secretory immune system in DS subjects.

A link between parotid salivary Ig level and recurrent respiratory infections in young Down's syndrome patients.

The purpose of the present investigation was to assess the correlation between recurrent respiratory infections and the levels of salivary Ig in a group of young Down's syndrome (DS) individuals. Twenty-three DS and 10 age- and sex-matched healthy individuals were included. DS individuals who had experienced three or more upper respiratory tract infections (n = 10) in the previous 12 months were compared to DS individuals who had not experienced recurrent respiratory infections (n = 13) and to healthy controls (n = 10). A statistically significant reduction in the Ig salivary secretion rate was recorded in the subgroup with recurrent respiratory infections. No significant differences were seen between the subgroup without recurrent respiratory infections and controls. It is suggested that the secretory immune system provides local immune protection against pathogens in the respiratory tract. Detection of salivary Ig levels may serve as a predictor of the susceptibility of DS individuals to recurrent respiratory tract infections.

The use of orthodontic treatment and immediate implant loading to restore the traumatic loss of a maxillary central incisor.

This clinical case describes a new orthodontic/surgical concept for immediate loading of hydroxyapatite-coated cylindric implants, placed at the end of orthodontic treatment, to restore a traumatically lost maxillary central incisor. Further clinical and histologic studies are necessary to promote routine clinical application of this technique.

Stafne's bone cavity in the anterior mandible: a possible diagnostic challenge.

Stafne was the first to report the presence of "bone cavities" in the angle of 35 mandibles. Such cavities generally appear in the area between the mandibular first molar and the mandibular angle, and are not considered rare. One of their primary radiological diagnostic features is the characteristic location below the mandibular canal. Stafne's bone cavity is relatively rare in the anterior mandible. The mandibular canal is not present in the anterior mandible. As a result, diagnosis in the anterior mandible may be missed. Needless treatment modalities such as endodontic treatment, bone trephining, and bone exploration may be conducted. The purpose of the present report is to describe a new case of Stafne's bone cavity in the anterior mandible and discuss the differential diagnosis process. The dental computerized tomography scan is suggested as the most suitable noninvasive diagnostic and follow-up modality for this bony configuration in the anterior mandible.

On the association between hypercholesterolemia, cardiovascular disease and severe periodontal disease.

BACKGROUND: Premature death in men is known to be significantly associated with coronary heart disease (CHD). More and more studies are pointing toward a possible association between periodontal disease and increased risk of cardiovascular disease. The association of poor oral hygiene and atherosclerosis can be explained by the effect of chronic inflammatory disease on blood rheology. The purpose of the present study was to assess the relationship between CHD and periodontal disease. PATIENTS AND METHODS: The study population included 1094 Israeli army service men aged 26-53 years (mean: 39+/-5 years). The study group comprised 151 subjects classified as having coronary heart disease CHD, i.e., myocardial infarction, and or anginal syndrome with angiographic evidence of significant coronary disease, or suffer from atherosclerotic risk factors, i.e., diabetes (fasting glucose) and HTN according to strict, well-established criteria. Blood levels of cholesterol and triglycerides were also determined. The severity of periodontal disease was assessed by the aid of CPITN. The control group comprised 943 healthy subjects. Statistical analysis was performed with chi2 test. RESULTS: Statistical analysis showed a significant association of CPITN score 4 with hypercholesterolemia and a possible association with CHD. CONCLUSIONS: The generation of higher cholesterol blood levels is proposed as a possible link between chronic periodontal inflammation and atherosclerosis.

Recurrent oral ulcerations associated with recurrent herpes labialis--two distinct entities?

We investigated the prevalence of recurrent aphthous ulcerations (RAU) and recurrent herpes labialis (RHL) in a young adult population. The study group consisted of 20,689 soldiers (aged 18-21 years, mean 19.8 +/- 1 years). There were 14,991 men and 5,698 women. Every patient was asked to complete a self-report health questionnaire which requested information about the occurrence of either RAU or RHL. Data were analyzed using the chi-square test, and the odds ratio was also determined. The prevalence of RAU and RHL was 6.2% and 5.4%, respectively. The prevalence among women was significantly higher (P<0.001), than among men for both RAU (7.1% and 5.8%, respectively) and RHL (6.8% and 4.9%, respectively). Among women, the chance of having RAU for those who were RHL positive was 6.88 greater than for those RHL negative. Among men, the chance of having RAU for those who were RHL positive was 12.37 greater than for those RHL negative. In women, the chance of having RHL for those who were RAU positive was 6.88 greater than for those who were RAU negative. In men, the chance of having RHL for those who were RAU positive was 12.37 greater than for those who were RAU negative. It is concluded that a similar underlying pathological process or unknown cofactor may be involved in both RAU and RHL.