The antimicrobial effectiveness of photodynamic therapy used as an addition to the conventional endodontic re-treatment: a clinical study.

BACKGROUND: The purpose of the study was to evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) used as an adjunct to the endodontic re-treatment in the eradication of microorganisms from previously filled root canals. METHODS: The study sample consisted of 21 randomly selected patients with root filled and infected root canal system with chronic apical periodontitis on incisors or canines, who have had previously endodontic treatment. Microbiological samples from the root canals were collected after accessing the canal, following the endodontic re-treatment and after the aPDT procedure. During instrumentation, the root canals were irrigated with 2.5% sodium hypochlorite (NaOCl), and the final irrigation protocol included 17% ethylenediaminetetraacetic acid followed by NaOCl. Root canals were filled with a phenothiazinium chloride and irradiated with a diode laser (λ=660 nm, 100 mW) for 1 min. Microbiological samples from the root canals were cultivated on selective plates, and the identification was done by micromorphology, macromorphology and different API strips as well as bacterial counts (colony forming units). RESULTS: Fourteen bacteria species were isolated from the root canals initially, with a mean value of 4.57 species per canal. Although endodontic re-treatment alone produced a significant reduction in the number of bacteria species (p<0.001), the combination of endodontic treatment and aPDT was statistically more effective (p<0.001). No bacteria were cultivated from the main root canals of 11 teeth. CONCLUSION: The results indicated that the aPDT used as an adjunct to the conventional endodontic therapy achieved a significant further reduction of intracanal microbial load.

Morphological and ultrastructural comparative analysis of bone tissue after Er:YAG laser and surgical drill osteotomy.

OBJECTIVE: The purpose of this study was to analyze morphological, chemical, and crystallographic changes of bone tissue after osteotomy performed with an erbium:yttrium-aluminium-garnet (Er:YAG) laser and a low speed pilot drill. MATERIALS AND METHODS: Bone blocks were prepared from porcine ribs, and on each block, two tunnel preparations were performed using the Er:YAG laser (pulse energy: 1000 mJ, pulse duration: 300 µs, pulse repetition rate: 20 Hz) or the low-speed surgical pilot drill. The morphological changes of the cortical and the spongious surface of the tunnel preparations were analyzed under the field emission scanning electron microscopy (FE-SEM) at low and high resolution. The distribution and the level of chemical elements in the treated surfaces were evaluated by qualitative and semiquantitative energy dispersive x-ray analysis (SEM-EDX). Diffraction x-ray analysis was used to detect any differences and thermally induced modifications of hydroxyapatite crystals. RESULTS: FE-SEM revealed sharp edges of the Er:YAG preparations, with empty intertrabecular spaces and no signs of carbonization. In the drill group, the surface of the preparations was smooth, completely covered with smear layer and microcracks, and with hairy-like irregularities on the edges. SEM-EDX analysis did not reveal any differences in the number of specific chemical elements between the laser and the drill group. There were no thermally induced modifications of hydroxyapatite crystal structure in the bone tissue in either group. CONCLUSIONS: The Er:YAG laser ablation did not cause any chemical or crystallographic changes of the bone tissue. Compared with the drill, Er:YAG laser created well-defined edges of the preparations, and cortical bone had no smear layer.

Jaw injuries of independence victims from the 1991 War in Croatia.

In the aetiology of maxillofacial injuries, car accidents, violence, sports injuries and lately war injuries are frequently mentioned. The purpose of this study was to exhibit and analyse types of jaw injuries on bodies exhumed from massive and individual graves located in regions temporarily occupied during the War in Croatia that lasted from 1991 to 1995. The sample was the post-mortal documentation of the orofacial region (set of teeth, photographs, radiographic images) of 1068 victims exhumed from massive grave sites in Croatia. The jaw traumatism was analysed on the whole sample as well as on individual graves, whilst the analysis of trauma frequency was performed separately. Descriptive statistics were computed and the value of P < .05 was accepted as statistically significant. Results of this study showed that out of 1068 examined corpses, 332 had midface and lower face fractures, which was 31.1% of the total number. Lower face fractures were more frequent with 28.1%. Age related frequency analysis showed a significant dependency. There were 34.6% of fractures in the under 30 age group, 34.2% in those aged 30-60, while 21.3% of fractures were noted in the over 60 age group. Female bodies had the lowest number of jaw fractures regardless of the osteoporotic changes. The results of this study suggest that younger and middle aged persons were molested more. Jaw fractures suggest ante-mortal molestation. In females, the more likely fracture causes were the falls of the bodies into the graves or body to body hits.

Evaluation of sentinel node biopsy in oral carcinomas.

It is still a matter of debate whether sentinel node biopsy might replace neck dissection in patients with clinically negative neck lymph nodes who suffer from oral squamous cell carcinoma. In 30 patients (26 male, 4 female, average age 59.4 years) with oral squamous cell carcinoma we performed ultrasound guided punction of the lymph nodes which were lymphoscintigraphically seen together with histopatological analysis of the dissected node. Sentinel lymph node was seen in 93% cases. By use of lymphoscintigraphy sentinel node was verified in 23 patients. Ultrasound guided punction showed presence of regional disease in 10% of cases, whereas sentinel biopsy revealed 23 of the converted necks. Histopathological findings were positive in 33% of our patients. The results of this study revealed that sentinel biopsy did not reveal 27% of the patients with positive neck histopathology. In conclusion, sentinel node biopsy should be performed in selective cases as in some localizations it is easier to perform neck dissection in comparison to the sentinel node biopsy.

Use of recombinant human bone morphogenetic protein (rhBMP2) in bilateral alveolar ridge augmentation: case report.

In recent years, the delivery of osteoinductive factors such as bone morphogenic proteins (BMPs) has become an alternative approach to traditional bone grafting due to their capacity to produce bone healing and new bone formation. BMP-2 has proved to possess the highest osteoinductive potential among BMPs. The case reported the clinical use of recombinant human BMP-2 for bilateral vertical alveolar ridge augmentation. In a case of 61 year-old patient with a significant bilateral vertical bony deficiency of the mandible, rhBMP-2 administered via an absorbable collagen sponge carrier (ACS) was used for bilateral alveolar ridge bone induction. Augmented sites were covered and fixed with titanium mesh. Augmented sites were reopened 6 months after surgery. Titanium membrane and retaining screws were removed and three dental implants were placed. The tissue samples for the histologic analysis were harvested. Following 3 months healing period, the submerged implants were uncovered and restored with zirconium-ceramic crowns. Cone beam computed tomography (CBCT), panoramix and 3D radiographic evaluation were obtained prior to and after the surgical procedure. Vertical gain of the bone was 5.5 mm on the left and 5 mm on the right side, with 6 mm width of the bone. Histologic analysis revealed formation of mature trabecular bone with signs of osteoblastic proliferation. Implant stability quotient (ISQ) values were in the range between 69 and 75 for all three implants. No suppuration, gingival recession or pain were present 24 months after surgery. Vertical bone augmentation using rhBMP-2 is optional treatment modality to consider when planning dental implant placement in sites where severe vertical insufficiency exists.

The influence of psychological state on oral lichen planus.

Oral lichen planus (OLP) is a T-cell mediated disease directed to a still unknown antigen, which may affect oral mucosa. The aim of this study was to determine whether differences in anxiety, depression and stress could be seen in patients with OLP in acute stage and in remission, as well as in comparison with healthy control subjects. The study included 50 OLP patients aged 22-79 (mean age 61.04) years and 50 control subjects who had healthy oral mucosa aged 38-80 (mean age 58.70) years. Patients with OLP filled out the State-Trait Anxiety Inventory for Adults and Beck Depression Inventory II test in acute stage and in remission. Control subjects also filled out the same tests. On detailed medical history, study subjects were asked about the possible stressors, which might have happened in the previous year. Statistical analysis was performed by use of descriptive statistics and t-test. There were no differences in the level of anxiety, depression and stress between the two stages of OLP disease (acute vs. remission period). Patients with OLP were significantly more anxious, depressed and stressed in both OLP stages as compared with healthy controls. It might be that psychological disturbances precede OLP development rather than worsening the disease process itself.

The prevalence of proximal fractures of dental crowns with amalgam fillings.

The purpose of this paper was to determine the prevalence and impact of various etiological factors on marginal ridge fractures of teeth with amalgam fillings. 50 subjects participated in this research, 172 teeth restored with amalgam were examined out of which 28 premolars and 144 molars of both jaws. Data used in the research was obtained by nonaggressive exploration of oral cavity and by checking dental charts and radiographic charts of patients. Patients were divided in three gendered age groups. Etiological factors used in the research were: the position of teeth in jaws, classification of amalgam fillings according to Black, the duration of fillings, the presence of caries on proximal surfaces not included in restoration and tooth vitality. Also, Angle Class, habits and presence of fixed prosthetic appliances in opposite jaw were taken into consideration. Results for each patient were separately written in the questionnaire. Statistical analysis was carried out by Pearson's chi2-test. According to obtained results 51% of teeth with amalgam fillings have a fracture of marginal ridge. Statistically significant factors that influenced the occurrence of fractures of proximal surfaces in this research were classification of amalgam fillings according to Black, the patient's age and the existence of caries on proximal surface.

Assessing health-related quality of life outcomes after the surgical removal of a mandibular third molar.

This study was designed to assess the impact of the surgical removal of a mandibular third molar on health-related quality of life (HRQoL) in the postoperative period. Data was obtained from 101 patients who had undergone 105 surgical procedures. Only one mandibular third molar was removed per visit. The inclusion criterion for surgical procedures was creating a mucoperiosteal flap either with or without osteotomy. Surgical details were noted in a pre-made questionnaire. A self-administered health-related quality of life questionnaire, designed for assessment of the patient's perception of recovery for pain, lifestyle and oral function, was given to all patients. Patients evaluated postoperative pain and other sequelae on a scale ranging from 0 (none) to 3 (severe). Follow-up visits were scheduled on the third and the seventh postoperative day, when wound healing was clinically evaluated and noted. At the review appointment, one week later, patients had their sutures removed and returned a completed follow-up questionnaire. Patients were contacted 14 days after surgery for the purpose of gathering additional data pertaining to their recovery. The mean score for pain had a peak value on day one (1.8), and showed an exponential decrease (1.2 on day three, 0.5 on day seven, 0.1 on day 14). All the other postoperative sequelae showed the same tendency to decrease exponentially. The type of operative procedure and tooth position showed significant impact on postoperative recovery. The surgical removal of a mandibular third molar causes severe deterioration in a patient's quality of life during the first 3 days postoperatively. The quality of life can be expected to return to a preoperative level by the end of the first postoperative week.