Jyrki Vuola

Compressive strength of calcium carbonate and hydroxyapatite implants after bone-marrow-induced osteogenesis

Natural coral and structurally similar porous hydroxyapatite (HA) have been used as bone substitutes. They are not osteoinductive but bone formation can be induced by marrow cells, even in extraosseal sites. In our previous study we induced bone formation in porous coral and HA after having implanted the materials in intramuscular pockets in rat. New bone formed only in HA or coral implants soaked with marrow cells; fibrous tissue ingrowth alone was observed in the controls (without marrow). In the present study we examined the effect of tissue ingrowth on the mechanical properties of coral and HA implants obtained in a similar process to that used before. At 12 weeks the compressive strength of HA was higher in the marrow group than in the controls; it was also higher than that of the wet unimplanted material. The HA blocks did not show resorption. Coral resorbed quickly and lost its compressive strength, which was originally higher than in HA. At three weeks the marrow group was stronger than the control specimens. After six weeks only the marrow group, but not the controls, could be tested. Bone ingrowth seemed to maintain the strength of the coral implant even if it was dissolving. The mechanical strength of both materials was comparable to that of cancellous bone.

Bone marrow induced osteogenesis in hydroxyapatite and calcium carbonate implants

In this experimental study, blocks of natural coral (calcium carbonate) and its structurally similar derivate in the form of hydroxyapatite (calcium phosphate) were implanted in rat latissimus dorsi muscle with autogenous bone marrow to compare their bone-forming capability. A block without marrow placed in the opposite latissimus muscle served as a control. The animals were killed at 3, 6 and 12 weeks and, in the hydroxyapatite group, also at 24 weeks. The sections were analysed histologically and histomorphometrically. Bone was found only in implants containing bone marrow. Bone formation was significantly (p < 0.05) higher in coral than in hydroxyapatite implants at 3 weeks (10.8% versus 4.8%) and at 12 weeks (13.7% versus 6.3%, bone/total original block area). At 12 weeks all the coral implants had lost their original structure, and the cross-sectional area of the block had diminished to 40% of the original area.

Mental disorders after burn injury: A prospective study

OBJECTIVEnTo prospectively investigate variations in prevalences of mental disorders after burn, and correlation between burn severity and mental disorders among hospitalized burn patients.nnnMETHODnA cohort of 107 consecutive acute adult burn patients was examined with structured diagnostic interview (SCID-I) at baseline, and 92 patients (86%) at 6 months after injury. Prevalences of mental disorders for the whole 6-month follow-up period, plus 1-month point prevalences in acute care and in a second 6-month interview were assessed, and the two point prevalences were compared. Burn severity was estimate by %TBSA.nnnRESULTSnDuring the 6-month follow-up 55% (51/92) of burn patients had at least one mental disorder, including 12% (11/92) with post-traumatic stress disorder (PTSD). In a multinomial regression, %TBSA exposure independently and strongly predicted risk for mental disorders, especially for anxiety disorders and delirium. The overall point prevalence of mental disorders decreased significantly (p=0.036) from acute care (45%) to 6 months (33%).nnnCONCLUSIONSnAfter burn, more than half of the patients suffer from some type of mental disorder, but the prevalence declines over time after the acute phase. The disorders are not limited to depression and PTSD. A strong relationship likely exists between burn severity and some post-burn mental disorders.

Mental disorders among acute burn patients

OBJECTIVEnTo investigate mental disorders among acute hospitalized burn patients.nnnMETHODnConsecutive acute adult burn patients (n=107) admitted to Helsinki Burn Centre were interviewed by an experienced psychiatrist with the Structured Clinical Interview for DSM-IV-TR for Axis I and II mental disorders assessed in three time frames (lifetime, the month prior to burn, and in acute care). Information on clinical features, psychiatric symptoms, personality traits, and burn severity (total body surface area, TBSA) was gathered.nnnRESULTSnThe mean TBSA was 9%. Most (61%) acute burn patients had at least one lifetime Axis I or II mental disorder. Prevalences of lifetime substance-related disorders (47%), psychotic disorders (10%), and Axis II personality disorders (23%) were high. The overall prevalence of Axis I mental disorders increased significantly (Q=6.40, df=1, p=0.011) from the month prior to burn (40%) to acute care (48%). The prevalence of delirium for this period was significantly higher (0.9% vs. 13%; Q=13.00, df=1, p<0.001) in acute care.nnnCONCLUSIONSnMental disorders, particularly substance use disorders, psychotic disorders, and personality disorders are common among acute burn patients before injury. These disorders may predispose to burns. Burn itself may also predispose to mental disorders, particularly delirium.

Return to employment after burn

The increase in the survival rate of burned patients has stressed the need to study their rehabilitation. The purpose of our study was to characterize the factors influencing such patients return to work. We conducted a mail survey among 316 patients aged 15-65 years, treated at Töölö Hospital Burns Unit between 11 November 1988 and 31 December 1994. Of 175 participants, 130 (74 per cent) were men and 45 (26 per cent) women. The mean TBSA was 14.0 per cent, mean FT 6.4 per cent and the mean time of hospital treatment (TOT) 17.5 days. Statistical significance was calculated by Mann-Whitney U test, Kruskall-Wallis one-way analysis of variance and Chi-square test as appropriate, with a probability level of 0.05. In the study, 54 per cent of patients whose burn area was 1-10 per cent, returned to work within 2 months. No difference was found between patients who had hand burns and those who had burn injuries in other parts of the body. Patients who did not return to work were significantly older (mean age 45 years) than those who did (mean ages varying from 33 to 36 years; P < 0.05). Total body surface area burned (TBSA), FT, TOT, age and employment status at the time of injury were the factors predicting the resumption of working ability after burn injury.

Human skin transcriptome during superficial cutaneous wound healing.

Healing of the epidermis is a crucial process for maintaining the skins defense integrity and its resistance to environmental threats. Compromised wound healing renders the individual readily vulnerable to infections and loss of body homeostasis. To clarify the human response of reepithelialization, we biopsied split‐thickness skin graft donor site wounds immediately before and after harvesting, as well as during the healing process 3 and 7 days thereafter. In all, 25 biopsies from eight patients qualified for the study. All samples were analyzed by genome‐wide microarrays. Here, we identified the genes associated with normal skin reepithelialization over time and organized them by similarities according to their induction or suppression patterns during wound healing. Our results provide the first elaborate insight into the transcriptome during normal human epidermal wound healing. The data not only reveal novel genes associated with epidermal wound healing but also provide a fundamental basis for the translational interpretation of data acquired from experimental models.

The changing surgical management of juvenile nasopharyngeal angiofibroma

The management of juvenile nasopharyngeal angiofibroma (JNA) has changed during the last decades but it still continues to be a challenge for the multidisciplinary head and neck surgical team. The aim of this study was to review the used treatment approach and outcome of JNA in a single institution series of 27 patients diagnosed and treated during the years 1970–2009. All patients were male, with the median age of 17xa0years (range 11–33xa0years). Surgery was used as the primary treatment in every case. Surgical approaches varied, transpalatal approach (Nxa0=xa014) being the most common approach used in this series. During the last decade various other techniques were applied, including endoscopic (Nxa0=xa03) resection. Two patients were additionally treated with antiangiogenic agents and one patient with stereotactic radiotherapy. The primary recurrence rate was 37% and it seemed to correlate with vascular density of tumour and the surgical approach used. We suggest that the management of JNA should be planned by an experienced head and neck surgeon, as part of a multidisciplinary team, preferably in a tertiary referral setting, and the recent development of the available therapies should be taken into account to minimise the risk of recurrence.

Natural coral as bone-defect-filling material.

Natural coral (NC) has been studied experimentally and clinically as a bone substitute, but its resorption rate and possible replacement by bone still need to be defined in humans. In this study bicortical bone was harvested from the iliac crest of 10 patients. The defect was filled with a NC block, and changes were monitored by X-rays and quantitative CT scans for a mean of 2.1 years. A biopsy was taken at 1 year. The purpose of the study was to investigate the resorption rate and pattern of NC (Porites) implants and the replacement, if any, of the implant by new bone. The blocks underwent centripetal resorption, but all the blocks still could be detected by X-rays and CT scans at the end of the follow-up period. The density of the remaining block did not change. Seven of the 10 implants were smaller than 50% of their original size at the end of the study. Bone ingrowth could be observed only in two of seven biopsies. One implant had to be removed after 1.7 years due to infection. The study shows that resorption of natural coral proceeds centripetally and apparently more rapidly when accompanied by tissue ingrowth. None of the blocks resorbed completely, and the defect at the iliac crest had not been restored by the end of the study.

Oropharyngeal carcinoma and its treatment in Finland between 1995-1999: a nationwide study.

The survival figures for advanced stage oropharyngeal carcinoma (OPC) have remained moderate in spite of radical combined modality treatments. The purpose of this study was to investigate the used treatment approach and the outcome of OPC in a nationwide study. Retrospective clinicopathological data of all patients diagnosed with OPC between 1995 and 1999 at the five university hospitals in Finland were reviewed. All patients had a minimum 4-year follow-up. A total of 168 patients (145 men and 23 women, mean age 59xa0years; range 28 – 89xa0years) were included. The T categories were as follows: T1, n =34; T2, n =55; T3, n =40; T4, n =39. One hundred and seventeen (69.6%) patients presented with neck node metastases and three (1.8%) patients with distant metastases. In the majority (61.3%) of the patients the tumor was located in the lateral wall of the oropharynx. In 144 (85.7%) patients the treatment was performed with curative intent. Of these, surgery of the primary tumor was performed in 123 (85.4%) patients, and the defect was reconstructed with a pedicled flap or free tissue transfer in 66 (53.7%) of these patients. A neck dissection (ND) was performed in 86 (69.9%) out of these 123 cases. Surgery was the only treatment modality in 10 (6.9%) patients. Radiation therapy (RT) only (with or without chemotherapy) was given to 21 (14.6%), combined treatment with surgery + radiation therapy (S + RT) to 110 (76.4%) and surgery + chemoradiotherapy (S + CRT) to 3 (2.1%) patients. Overall (OS) 3- and 5-year survival rates were 58 and 45%, respectively. Disease-specific (DSS) 5-year survival rates by T-class for the patients treated with curative intent were as follows: T1, 77%; T2, 70%; T3, 66%; T4, 53%. The variable treatment approach, the frequent locoregional recurrences and the moderate survival point out the need to consider new strategies in the management of OPC.

Oral tongue carcinoma and its treatment in Finland.

Management of oral tongue squamous cell cancer (OTSCC) remains a challenge. This nationwide study reports the used treatment approach and the outcome of OTSCC in Finland. Retrospective study of OTSCC patients in 1995–1999 with a 5-year follow-up. The corresponding data from 1980 to 1989 is also included. About 235 patients (125 M, 110 F; mean age 61.6xa0years; range 24–90xa0years) were included, 77% had SCC of lateral border of the tongue and 25% were N+. Treatment with curative intent was given to 224 (95%) patients. Surgery of the primary tumour was performed in 218 (97%) patients and with a reconstruction in 69 (31%) patients. A neck dissection was performed ipsilaterally in 114 (51%) and bilaterally in 9 (4%) cases. Irradiation was given to 131 (58%) patients. The rate for locoregional recurrence was 28%. The 3- and 5-year overall survival (OS) rates were 66 and 47%, respectively. The corresponding disease specific survival (DSS) rates were 74 and 64%, respectively. The mean DSS for patients younger than 40xa0years and older than 40xa0years was 111 and 88xa0months, respectively (Pxa0<xa00.02). The 3- and 5-year DSS rates were: Stage I, 88 and 74%; Stage II, 74 and 62%; Stage III, 79 and 71% and Stage IV, 36 and 33%, respectively. In the present study the surgical treatment approach seems effective in controlling early stage OTSCC but the modest survival, in spite of combination of radiotherapy and surgery, points out the need to consider new strategies in the management of advanced stage disease.